Thèses : « Science liter »

1

Frandsen, Kimberly J. « Reading and Writing in Science : How do the Reform Documents Attend to the Fundamental Sense of Science Literacy ? » Diss., CLICK HERE for online access, 2006. http://contentdm.lib.byu.edu/ETD/image/etd1417.pdf.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

2

Marinho, Andrew Yan Solano. « Do cientista ao ativista : os problemas da ci?ncia do texto e uma solu??o revolucionaria na obra de Terry Eagleton ». Universidade Federal do Rio Grande do Norte, 2014. http://repositorio.ufrn.br:8080/jspui/handle/123456789/16342.

Texte intégral

Résumé :

Made available in DSpace on 2014-12-17T15:07:11Z (GMT). No. of bitstreams: 1 AndrewYSM_DISSERT.pdf: 1257696 bytes, checksum: 309b05179e3d4e5c72b883b5c4785af1 (MD5) Previous issue date: 2014-05-28
Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico
The literary critic Terry Eagleton obtained notoriety in academic circles when he was recognized intellectually for his bestselling book Literary Theory: An Introduction. In this book, the English author boldly proposes the end of literature and literary criticism. However, Eagleton proposed years before, in his book Criticism and Ideology (1976), a scientific system of analysis of literary texts, which seemed less radical, both in theory and in method, than in his later theoretical proposal. Based on this, the objective of this dissertation is to present the English literary critic?s initial method, explaining the reasons that led him to abandon his initial project - of develop a method of analysis of the literary text on a Marxist scientific perspective - and to propose, in the following years, in his most famous book and others, a revolutionary vision that would go beyond textual analysis and make literary texts have a practical intervention in society. Finally, we explain what would be his idea of revolutionary criticism
O cr?tico liter?rio Terry Eagleton obteve notoriedade no meio acad?mico ao ser reconhecido intelectualmente com seu livro best-seller Teoria da Literatura: uma introdu??o. Nesse livro, o autor ingl?s prop?e, ousadamente, o fim da literatura e da cr?tica liter?ria. Contudo, anos antes, Eagleton prop?s, no livro Criticism and Ideology (1976), um sistema cient?fico de an?lise do texto liter?rio aparentemente menos radical, tanto em teoria quanto no m?todo, que sua proposta te?rica posterior. Com base nisso, o objetivo dessa disserta??o ? apresentar o m?todo inicial do cr?tico liter?rio ingl?s, explicitar os motivos que o levaram a abandonar seu projeto inicial de elaborar um m?todo de an?lise do texto liter?rio sobre uma ?tica cient?fica marxista e a propor, nos anos seguintes, em seu livro mais famoso e em outros, uma vis?o revolucion?ria, que iria muito al?m de an?lises textuais e faria os textos liter?rios terem uma interven??o pr?tica na sociedade. Por fim, explicitaremos qual seria sua ideia de cr?tica revolucion?ria

Styles APA, Harvard, Vancouver, ISO, etc.

3

Tector, A. Joseph. « Discordant liver xenotransplantation in recipients with liver failure ». Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=84439.

Texte intégral

Résumé :

Liver xenotransplantation could eliminate the liver donor shortage, but currently it is not possible because of a lack of understanding of liver xenograft rejection. Hyperacute xenograft rejection is initiated by the binding of preformed naturally occurring xenoreactive antibodies (XNA) to the xenograft endothelium. The XNA bind to the xenograft endothelium, leading to complement-mediated endothelial injury.
Liver xenotransplantation will be initially offered to patients with severe liver failure as a bridge to a human liver transplantation. The hypothesis tested in this thesis is that hyperacute rejection of liver xenografts placed into recipients with liver failure will be diminished because of the complement deficiency that accompanies liver failure. The experiments described in this thesis detail the development of an in vitro pig-to-human liver xenotransplant model incubating cultured pig hepatic endothelial cells (PHEC) and human serum in culture. We showed that either classical or alternative complement pathways could initiate endothelial injury. Next we developed the dog-to-pig liver xenograft model and characterized the lethal coagulopathy that results from hyperacute rejection. The coagulopathy results from the lack of function of platelets as well as their disappearance from the circulation. We then used the galactosamine induced liver injury model in porcine recipients of canine liver xenografts to demonstrate that hyperacute rejection in the setting of liver failure is diminished. We showed that; tissue injury, coagulopathy and platelet defect, and endothelial injury were diminished. Our experiments suggested that the cause of the decreased injury was the lack of complement in the pigs with galactosamine induced liver injury since the XNA levels were no different than in control animals. Our final experiments evaluated serum from patients with liver failure and compared the injury caused by incubation with PHEC. Serum from the liver failure patients had similar levels of XNA when compared with normal subjects, but had less complement activity, and less C3 and C4. Incubation of liver failure serum with PHEC caused much less injury and complement activation than serum from control subjects. The results in this thesis suggest that liver failure will have a significant impact on liver xenograft rejection, helping to diminish hyperacut

Styles APA, Harvard, Vancouver, ISO, etc.

4

Bakas, Spyridon. « Computer-aided localisation, segmentation and quantification of focal liver lesions in contrast-enhanced ultrasound ». Thesis, Kingston University, 2014. http://eprints.kingston.ac.uk/30592/.

Texte intégral

Résumé :

The research presented in this thesis focuses on applications of Contrast Enhanced Ultrasound (CEUS) imaging and is coordinated to address current clinical requirements in the assessment, quantification and evaluation of liver cancer and in particular focal liver lesions (FLLs). The main outcomes of this research are methods to assist radiologists with automating these routinely performed manual image interpretation tasks, with the intention of supporting them to make their diagnostic decisions faster, more easily and with greater confidence. Such automatic analysis is challenging mainly because of the relative motion between the ultrasound transducer and the liver, the physiological motion of the patient and the dramatic intensity changes over time caused by the contrast-enhancing agents intravenously injected during a CEUS examination. The work described in this thesis can be divided into three principal themes. These are addressed in turn below. Firstly, a set of methods are proposed to assist in automating initialisation tasks required for the offline assessment of data acquired during CEUS liver scans. These tasks relate to the delineation of the area comprising the ultrasonographic image, the identification of the optimal reference frame for initialising an FLL, as well as the segmentation of the FLL boundaries on this frame. The potential clinical value of the proposed methods is that they can lead to easier and faster assessment of FLLs, whilst producing results less dependent on the human initialisation and hence improving the repeatability and reproducibility of the assessment of the examination and increasing the confidence of radiologists when making a diagnosis. Secondly, a variety of methods are investigated to estimate the motion observed within the ultrasonographic image of CEUS screening recordings and then compensate for this, allowing for an accurate quantification of the perfusion of tissue regions. Obtaining a perfusion curve for an image region, without compensating for the observed motion, may lead to erroneous diagnostic results as the specified image region may correspond to different tissue along the video sequence. Quantitative evaluation of the presented methods demonstrates their potential as reliable real-time motion compensation methods for such recordings. Finally, an alternative fully automatic method for the identification and localisation of potential malignancies is proposed. For such identification, and hence distinction between cases that include potentially malignant and benign lesions, an innovative assessment of the global spatial configuration of local variations of perfusion curves is presented. For the localisation of tissue regions of potential malignancy, a novel feature is proposed that encompasses spatio-temporal information (Le. the combination of both the variation in these local perfusion curves and the location they relate to) to cluster together neighbouring regions with similar dynamic behaviour. The clinical value of the identification part is the early diagnosis of an FLL’s type and the possibility for the discharge of patients with benign FLLs, leading to less distress to the patients and their families, as well as reduced healthcare costs. Additionally, the localisation part assists in enhancing the radiologist’s awareness of tissue regions with potentially malignant behaviour, as well as providing effortless localisation of such regions allowing for an objective initialisation of computer-aided segmentation methods improving the repeatability and reproducibility of the assessment of CEUS data. The key findings of this research indicate that: i) the optimal reference frame can be reliably identified in a fully automatic and deterministic manner, ii) the segmentation of an F LL can be performed in a rapid semi-automatic manner, which produces results that are, at worst, of comparable consistency as different manual annotations, iii) the apparent observed motion can be compensated in real-time, either locally or globally, and a simple translation is sufficient to achieve this, iv) the distinction between benign and malignant lesions can be performed in a fully automatic and deterministic manner, without missing a single malignancy, and v) potential malignancies can be localised reliably in a fully automatic manner. Quantitative analysis of all results on real clinical data, from a multi-centre study, is used to evaluate the level of confidence of the decision of the proposed methods and demonstrates the value of these methods in a diverse dataset acquired using the protocol of current standard care. A system incorporating the proposed methods could improve the current clinical practice for assessing, quantifying and evaluating FLLs in CEUS recordings. Specifically, it would be beneficial to radiologists, for cancer research, providing easier and faster assessment of FLLs whilst producing results less dependent on the human initialisation and therefore increasing the confidence of radiologists in their diagnostic decisions.

Styles APA, Harvard, Vancouver, ISO, etc.

5

Huda, Amina. « Employment after liver transplantation ». Diss., Search in ProQuest Dissertations & ; Theses. UC Only, 2010. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3398878.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

6

Merlo, Vittoria. « Abundance and composition of marine litter along the italian coasts : contribution from official monitoring and citizen science ». Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020.

Trouver le texte intégral

Résumé :

Assessment of amounts, distribution, composition and sources of beach litter was conducted on Italian coast in 2017. Data have been collected by scientific staff from the Regional Environmental Protection Agencies of Italy (MSFD), and by citizen scientists coordinated by the environmental association Legambiente (Clean Up the Med initiative). The vast majority of marine litter collected (>70%) were plastic objects, 30% of which were single-use plastic. In the investigated MSFD subregions, Adriatic Sea appeared to have the highest presence of fishing-related items (7.76%), Western Mediterranean Sea had a high number of cigarette butts and filters (8.19%) and Ionian and Central Mediterranean Sea had plastic bags (8%). Considering the level of urbanisation, rural beaches are the only one that showed a low abundance of Smoke-related litter (min-max: 0-21 items/100 m - <4%), urban beach resulted in having cigarette butts and filters (min-max: 6-140 items/100 m - 9.22%). “Non-sourced” items represented a large percentage of the litter found in all subregions and among beach type (29%-50%), together with “Public litter” (31% to 53%). Coastal Clean Index (CCI), used for testing the beach cleanliness, showed that most beaches were classified as Very Clean or Clean in both study periods investigated in the framework of the MSFD. Comparison between the MSFD monitoring and the Clean Up the Med initiative showed that there were no significant differences in the total density of beach litter detected, but there was a significant difference in terms of composition. This was probably due to the fact that Clean Up The Med survey was unbalanced between regions, due to the voluntary nature of the project. The results remarked how urgent is a national action against beach littering (plastic in particular), and the need in a global shift in human mindsets and behaviour, that could happen also thank to the work of citizen science volunteers and environmental association as Legambiente.

Styles APA, Harvard, Vancouver, ISO, etc.

7

Petersson, Helena, et Ing-Marie Åström-Swahn. « Liten gruppEn kvalitativ studie av lärares och skolledares resonemang inför elevers placering i liten grupp ». Thesis, Kristianstad University College, Department of Behavioural Sciences, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:hkr:diva-3869.

Texte intégral

Résumé :

Syftet med följande arbete är att granska hur lärare och skolledare resonerar inför elevers placering i liten grupp. Skolans uppgift är att ge alla elever en likvärdig utbildning. Stöd ska ges till de elever som inte bedöms klara de nationella målen och det stödet ska i första hand ges inom ramen för den ordinarie undervisningen. Arbetet ger en överblick av tidigare forskning om hur en skola för alla växt fram ur ett historiskt perspektiv samt varför det krävs en allmän specialpedagogisk kompetens hos alla lärare för att kunna få en skola för alla. Med hjälp av kvalitativa intervjuer ville vi se hur den specialpedagogiska kompetensen såg ut, hur det förebyggande arbetet utformades, vad en liten grupp kunde ge som inte den ordinarie undervisningen kunde samt vilken utveckling som förväntades av eleven efter en placering i liten grupp. Sammanfattningsvis pekar resultaten på att lärare är mycket beroende av speciallärarnas och specialpedagogernas kunskaper och erfarenheter. Lugn och ro och uppbyggandet av positiva relationer samt en chans att nå de nationella målen var de viktigaste fördelarna med liten grupp. Nackdelarna var att eleverna kan få en stämpel som är svår att sudda bort och att många elever blir kvar i liten grupp även när de inte behöver.

Styles APA, Harvard, Vancouver, ISO, etc.

8

Owoseni, Seun Emmanuel. « The Study of Alcoholic Liver Diseases ». Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/etd/3493.

Texte intégral

Résumé :

Excessive alcohol consumption is the primary contributing factor in the development of alcoholic liver diseases (ALD). Nicotine contained in tobacco is a major addictive alkaloid, which enhances the effects of ALDs. The major enzyme involved in nicotine metabolism is cytochrome P450 2A5 (CYP2A5) which is produced in the liver. Alcohol can stimulate the CYP2A5 enzyme. We utilized cyp2a5-/- knockout mice in this research to examine the effects of CYP2A5. The cyp2a5-/- mice and wild-type (WT) mice were fed liquid ethanol diet with or without nicotine to induce ALD. Nicotine enhancing effects on ALD were observed in WT mice but not in cyp2a5-/- mice. Oxidative stress was stimulated by alcohol and further increased by nicotine in WT mice but not in cyp2a5-/-mice. Microsomal ROS production during microsomal metabolism of nicotine was increased in WT mice but not in cyp2a5-/-mice. These results suggest that nicotine enhances ALD is CYP2A5 dependent.

Styles APA, Harvard, Vancouver, ISO, etc.

9

Luotonen, David. « Utveckling av ett webbaserat ekonomisystem för en liten organisation ». Thesis, Jönköping University, JTH, Computer and Electrical Engineering, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-9652.

Texte intégral

Résumé :

Jönköpings styrkelyftarklubb är en liten organisation som behöver ett snabbare sätt att hantera sin bokföring.

Syftet med detta arbete är att undersöka utvecklingen av ett Internetbaserat ekonomiprogram för användning av utvalda i en liten organisation samt utreda vilka metoder och verktyg som är lämpligast för uppgiften utifrån de krav som finns.

OOS/UML-modellen som delar in utvecklingsprocessen i 4 steg används. Bara de 3 första stegen behandlas i denna rapport: planering, prototyputveckling och konstruktion. Det teoretiska ramverket berör flera relevanta ämnen för detta projekt. Den första delen innehåller information om öppen källkod och avslutas med en beskrivning av det valda skriptspråket: php. Den andra delen fokuserar på databaser, och går från generella designteorier till användningen av MySQL och säkerhetsproblem. Den tredje delen fortsätter på området säkerhet, och behandlar förutom säkerhet i databaser även kryptering på webben. Den fjärde delen beskriver ekonomiska system och deras utveckling och användning. Kapitlet avslutas med en kort titt på Ajax som ett medel för ökad användbarhet.

Arbetet ledde till några allmänna slutsatser om utvecklingen av ett system som detta. Planering är viktigt eftersom tidsåtgång är svårt att förutse och systemet inte kommer kunna ersätta vare sig ekonomiprogram eller webbutiker till fullo. Att använda existerande lösningar på programmeringsproblem sparar tid, och ibland är det värt att ändra i designen för att kunna använda en sådan. Avslutningsvis bör man prioritera egenskaper, eftersom en kombination av system som detta annars kan bli allt för stort och komplext. Prestanda, användbarhet, kostnad och säkerhet är aspekter som alla tävlar om samma resurser. I detta projekt visade prestanda och kostnad sig vara viktigast och fick prioriteras.

Styles APA, Harvard, Vancouver, ISO, etc.

10

Brandi, Denis. « SCADA Lite View ». Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amslaurea.unibo.it/6583/.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

11

Sandell, Liiza, et Sandra Svenningsson. « Liten kommun, stort ansvar ». Thesis, Malmö högskola, Fakulteten för lärande och samhälle (LS), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-29415.

Texte intégral

Résumé :

I januari 2015 genomfördes en ny lag som heter kommunens aktivitetsansvar för ungdomar. I och med lagen är nu kommunerna skyldiga att erbjuda ungdomar 16 – 19 år individuellt anpassade åtgärder. I första hand syftar lagen till att motivera ungdomen tillbaka till studier eftersom att allt pekar på att studier är centralt för att öka sina chanser på arbetsmarknaden. Skolinspektionen genomförde en granskning av hur kommunerna i Sverige arbetar med det kommunala aktivitetsansvaret och granskningen visar att flera kommuner inte uppfyllde de skyldigheter som den nya lagen kräver. Syftet med vår studie är att undersöka hur en kommun arbetar med aktivitetsansvaret samt ta reda på vilka behov tjänstemännen anser att ungdomarna har. Vi vill även ta reda vilken roll SYV:en har i arbetet med aktivitetsansvaret samt att vi vill undersöka på vilket sätt Skolverkets allmänna råd efterföljs av kommunen. Vi anser att detta är angeläget då tidigare forskning visar att ungdomar utan gymnasieutbildning har svårare att etablera sig på arbetsmarknaden. Vi har i vår studie fyra frågeställningar: vad anser tjänstemännen att ungdomarna har för behov? Vilka insatser upplever tjänstemännen är mest meningsfulla för ungdomarna? Vilken roll har studie- och yrkesvägledaren i arbetet med aktivitetsansvaret? På vilket sätt arbetar man efter Skolverkets allmänna råd? Vi har använt oss av en kvalitativ undersökning för att genomföra vår studie. För att analysera informanternas svar har vi använt oss av Linda Gottfredson teori om begränsningar och kompromiss samt Aron Antonovskys KASAM. Vårt resultat visar på det finns ett behov av att utveckla kommunens arbete med aktivitetsansvaret. Ungdomarna är i behov av vägledning samt att stärka sin självuppfattning. SYV:ens roll ser vi kan utnyttjas på fler sätt än vad som görs i dagsläget i kommunen.

Styles APA, Harvard, Vancouver, ISO, etc.

12

Gardemann, Andreas, Gerhard Püschel et Kurt Jungermann. « Nervous control of liver metabolism and hemodynamics ». Universität Potsdam, 1992. http://opus.kobv.de/ubp/volltexte/2011/5134/.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

13

Bacchiani, Lorenzo. « Sistemi NoSQL Lite : studio approfondito su Couchbase Lite ». Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2018.

Trouver le texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

14

Badger, Andrew Ashley 1970. « Alterations in chemically-induced liver injury by immunomodulators ». Diss., The University of Arizona, 1998. http://hdl.handle.net/10150/282642.

Texte intégral

Résumé :

Studies presented in this dissertation determined biochemical mechanisms underlying the modulation of chemical-induced liver injury by retinol and GdC₃ The first objective was to determine the role of inflammatory cells in the retinol potentiation of CCl₄-induced liver injury. Plasma alanine aminotranferase activities and histological analysis of liver sections both illustrated significant potentiation of CCl₄ hepatotoxicity by a single dose of retinol. The mechanism for this potentiation involves priming of Kupffer cells (KC) (i.e. by enhancing their response to toxic stimuli) as established by chemical inhibitors of KC, isolated KC, and immunohistochemical analysis of liver sections. Additional studies estimated the effect of retinol on non-inflammatory processes (i.e. cytochrome P450 (P450) activity). While total P450 content was not increased, the activity and concentration of CYP 2E1 were both significantly elevated following treatment with a single dose of retinol. These findings suggest that a single pretreatment with retinol potentiates CCl₄ hepatotoxicity by multiple mechanisms that involve increased biotransformation and inflammatory cell activities. Based on the findings with retinol, another immunomodulating agent, GdCl₃ might also alter the activity of hepatic biotransforming enzymes. Having established that GdCl₃ inhibits the activity of KC, the purpose of these studies was to determine the effect of GdCl₃ on the content and activity of hepatic P450. GdCl₃ treatment reduced total hepatic microsomal P450 as well as aniline hydroxylase activity by 30% in male and 20% in female rats. Hepatocytes isolated from rats pretreated with GdCl₃ were less susceptible to toxicity caused by CCl₄ but not cadmium, a hepatotoxic chemical not bioactivated by P450. Thus GdCl₃-mediated protection from toxicity in vivo might involve decreased biotransformation and inflammatory cell activities. Data presented in this dissertation suggest that, in addition to altering the inflammatory response to toxicants, retinol and GdCl₃ may modulate liver injury by altering the P450-mediated bioactivation of chemicals. Considering the multiple effects described here for each of these compounds, investigators should be cautious in the interpretation of data utilizing retinol or GdCl₃ to implicate KC as the sole contributor to toxicological mechanisms. This is especially important in models of chemical-induced injury in which bioactivation is a key feature.

Styles APA, Harvard, Vancouver, ISO, etc.

15

Woodfint, Rachel M. woodfint. « Identification of the LB-FABP promoter as a liver specific promoter via the generation of transgenic quail expressing eGFP within their liver cells ». The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1523880800285644.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

16

Evans, Alison. « The impact of selective beech (Nothofagus spp.) harvest on litter-dwelling invertebrates and the process of litter decomposition ». Lincoln University, 1999. http://hdl.handle.net/10182/1717.

Texte intégral

Résumé :

Minimising the potential impact of forest management requires an understanding of the key elements that maintain forest diversity and its role in ecological processes. Invertebrates are the most diverse of all biota and play important roles in maintaining forest processes. However, little is known about invertebrates in New Zealand's beech forests or the degree to which selective beech harvest might impact on their diversity and ability to carry out ecosystem processes. Studying ecosystem responses to disturbance is considered vital for understanding how ecosystems are maintained. One of the main objectives of this research was to assess whether litter-dwelling invertebrates were susceptible to the impacts of selective harvest and, if so, whether they could be used as indicators of forest health. Changes in invertebrate diversity could have important implications for nutrient cycling and primary production in forests. Litter-dwelling invertebrates contribute to the process of decomposition by increasing the surface area of the leaves, mixing soil organic matter and by infecting leaf particles with soil microbes. This investigation into the function of invertebrates in beech forest was carried out in the context of ecological theories which relate diversity to ecosystem stability and resilience. A replicated study was established in Maruia State Forest (South Island, New Zealand) to assess the potential biotic and abiotic impacts of sustainable beech harvest. Litter-dwelling invertebrates and environmental factors were monitored during 1997, before harvest, to determine how much variability there was between study sites. Specifically, litter pH, light intensity, litter fall, litter temperature, moisture as well as invertebrate abundance and diversity were compared before and after selective harvest. On 17 January 1998, two to three trees were selectively harvested from three of the nine study sites. On 15 February 1998 a similar number of trees were winched over or felled manually to create artificial windthrow sites. The remaining three undisturbed sites were used as controls. Invertebrates belonging to the detritivore guild were assessed from litter samples and a series of litter-bags containing pre-weighed leaf litter which were placed in each of the sites to assess rates of litter decomposition. Millipedes (Diplopoda: Polyzoniidae, Schedotrigonidae, Dalodesmidae, Habrodesmidae, Sphaerotheridae), earthworms (Oligochaeta: Annelida), tipulid larvae (Diptera: Tipulidae), weevils (Coleoptera: Curculionidae), moth larvae (Lepidoptera: Oecophoridae, Tortricidae and Psychidae), slaters (Isopoda: Styloniscidae), Oribatid mites (Acarina: Cryptostigmata) and landhoppers (Crustacea: Amphipoda) were extracted from the litter-bags and their abundance and diversity was compared between the three treatments. Weight loss from the litter-bags and the carbon and nitrogen content of litter were used to measure the rate of decomposition in each treatment. An additional study investigated whether exclusion of invertebrates from leaf litter resulted in reduced rates of decomposition. The results indicated that there was an increase in light intensity and a small increase in temperature following selective harvest and artificial windthrow. There was no significant difference in litter moisture or the amount of litter fall between the treatments. Invertebrate abundances were significantly affected by season but did not appear to be affected by selective harvest or artificial windthrow. The diversity of invertebrates remained relatively constant throughout the year, as did the rate of decomposition. When invertebrates were excluded from the leaf litter there was no consequential effect on the rate of litter decomposition. This suggests that there may be compensatory mechanisms taking place between the trophic levels of the food web to maintain processes and that direct links between invertebrates and decomposition are relatively weak. In conclusion, it appears that the effects of selective beech harvest on forest-floor processes were minimal and are comparable to those created by natural windthrow disturbance. It also appears that macroclimatic effects such as seasonal climatic effects have a large effect on forest biota. As none of the invertebrates studied appeared to be detrimentally affected by selective harvest and as there was no direct link demonstrated with decomposition, it was considered inappropriate to advocate the use of this group of invertebrates as indicators of sustainable forest management. The results from this study provide information which may help inform decisions on the future management of diversity in beech forest ecosystems.

Styles APA, Harvard, Vancouver, ISO, etc.

17

Sathelly, Balaji. « An Artificial Neural Network Approach to Predict Liver Failure Likelihood ». University of Toledo / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1535112414430542.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

18

Longley, Rhea Jessica. « Liver-stage vaccines for malaria ». Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:b5c9821c-db32-4b66-a315-02541e62f566.

Texte intégral

Résumé :

The development of an efficacious P. falciparum malaria vaccine remains a top priority. Pre-erythrocytic vaccine efforts have traditionally focussed on two well- known antigens, CSP and TRAP, yet thousands of antigens are expressed throughout the liver-stage. The work described in this thesis aimed to assess the ability of other pre-erythrocytic antigens to induce an immune response and provide protective efficacy against transgenic parasites in a mouse model. Research undertaken in our laboratory has demonstrated the ability of prime-boost viral vectored sub-unit vaccination regimens to elicit high levels of antigen-specific T cells. Eight candidate antigens were therefore expressed individually in the viral vectors ChAd63 and MVA. Two antigens, PfLSA1 and PfLSAP2, were identified that confer greater protective efficacy in inbred mice than either CSP or TRAP. PfLSA1 was also able to induce almost complete sterile efficacy in outbred mice, suggesting this vaccine should be assessed in a clinical trial. Immune responses to the candidate antigens were also assessed in human volunteers following their first exposure to controlled malaria infection. The antigen TRAP was further characterised by epitope mapping in volunteers vaccinated with ChAd63-MVA ME-TRAP. However, no functional T cell assay exists to measure inhibition of P. falciparum liver-stage parasites. An improved murine in vitro T cell killing assay was developed, and preliminary experiments were conducted that demonstrate the potential and promise of a P. falciparum T cell killing assay. Such assays will not only allow mechanistic studies to be undertaken, but could also change the way we screen pre-clinical liver-stage vaccines.

Styles APA, Harvard, Vancouver, ISO, etc.

19

Liaskou, Evaggelia. « MAdCAM-1 expression and function in human liver ». Thesis, University of Birmingham, 2010. http://etheses.bham.ac.uk//id/eprint/720/.

Texte intégral

Résumé :

Mucosal addressin cell adhesion molecule-1 (MAdCAM-1) is a tissue–specific protein that promotes α4β7+ lymphocyte recruitment on gut mucosal endothelium, playing an important role in the development of inflammatory bowel disease (IBD). Recent studies have reported its expression in liver diseases such as primary sclerosing cholangitis (PSC) and autoimmune hepatitis (AIH) that complicate IBD, therefore understanding the factors that drive hepatic expression of MAdCAM-1 might elucidate the pathogenesis of these diseases. In vitro stimulation of HSEC with tumor necrosis factor-α (TNFα) and methylamine, the physiological substrate of vascular adhesion protein-1 (VAP-1), as well as with the end products of methylamine deamination by VAP-1, resulted in increased levels of secreted and cell surface MAdCAM-1 protein that was able to support binding of α4β7+ lymphocytes under flow conditions. In vivo stimulation of mice that expressed hVAP-1 as a transgene, with methylamine, induced expression of MAdCAM-1 in Peyer’s patches and mesenteric lymph nodes, validating the effect of VAP-1 enzyme activity. In conclusion, we report for the first time that MAdCAM-1 is normally present in human liver and is further induced upon TNFα and methylamine stimulation resulting in the recruitment of mucosal cells to the liver, thus sustaining a destructive inflammatoty influx responsible for the establishment of chronic inflammation.

Styles APA, Harvard, Vancouver, ISO, etc.

20

Hartley, Jane Louise. « The molecular genetic investigation of paediatric liver disease ». Thesis, University of Birmingham, 2011. http://etheses.bham.ac.uk//id/eprint/1438/.

Texte intégral

Résumé :

Liver disease in children is rare but often serious, life long, and in many cases leads to death. Advances in diagnosing and treating liver disease (including liver transplant) have improved the outlook for children in many cases however little is known about the molecular pathogenesis of the disease, an understanding of which may identify specific therapeutic options. The aim of this thesis is to investigate the molecular genetics of rare liver disorders as the first step in advancing the understanding of liver disease pathogenesis. As a paediatric hepatologist I have identified cohorts of children in whom there is paucity of knowledge about the disease pathogenesis. I have studied three conditions in detail to encompass different clinical presentations. Chapter 3 summarises the investigation of the multisystem disorder, phenotypic diarrhoea of infancy (PDI), which causes cirrhosis or liver failure. Autozygosity mapping was used to identify the gene TTC37 in which mutations are associated with the PDI disease phenotype. Further work is now required to characterise TTC37, and use knockdown studies to identify whether TTC37 mutations are causative of the PDI phenotype. Chapter 4 describes the molecular genetic investigation of Jeune asphyxiating thoracic dystrophy (JATD), a chondrodysplasia with extra skeletal manifestations including hepatic ductal plate malformation and renal cyst development. Using autozygosity mapping, IFT80 was dentified in which mutations are associated with the JATD disease phenotype in 4% of ases. The diverse linical phenotype of JATD limits the utility of utozygosity mapping s it suggests there is genetic heterogeneity. The identification of IFT80 has led to JATD eing classified as a ciliopathy. Chapter 5 is the first description of eonatal liver failure to be associated with variants in ABCB11 which previously have only been associated with chronic liver disease and liver disease in pregnancy. This thesis has described the identification of the molecular genetic basis of rare causes of paediatric liver disease which has provoked many additional research questions. Future work will be to extend our knowledge of molecular genetics to all aspects of paediatric liver physiology so to classify disease according to the molecular pathogenesis such as a ciliopathy or bile salt transport defect.

Styles APA, Harvard, Vancouver, ISO, etc.

21

Sinha, Vikram Paritosh 1969. « Prediction of in vivo hepatic clearance of selected compounds using the isolated perfused rat liver, precision-cut liver slices and hepatocytes ». Diss., The University of Arizona, 1996. http://hdl.handle.net/10150/282203.

Texte intégral

Résumé :

The overall objective of this dissertation was to estimate the in vivo hepatic clearance (CL(H)) of compounds using in vitro methods of drug metabolism. The isolated perfused rat liver, precision-cut liver slices and hepatocyte were used to estimate in vitro CL(H) and compared to in vivo CL(H) Two compounds, benzoic acid and tolbutamide were chosen as model compounds. An isolated perfused rat liver (IPRL) apparatus was developed to measure hepatic extraction ratio. Three compounds, antipyrine, ethanol and lidocaine were used to characterize the apparatus. The ability of the IPRL to utilize oxygen was also investigated. Antipyrine extraction ratio was independent of perfusate flow rate, while the extraction of ethanol and lidocaine were flow-dependent. The extraction ratios of benzoic acid and tolbutamide were determined. The CL(H) of benzoic acid and tolbutamide was 4.43 ± 0.84 mL/min and 1.52 ± 0.59 mL/min, respectively. The intrinsic clearance of benzoic acid and tolbutamide was determined in precision-cut liver slices and scaled to the whole liver using total protein. The CL(H) of benzoic acid in rat liver slices was 2.13 ± 0.71 mL/min, while the intrinsic clearance in humans was 270 mL/min. The CL(H) of tolbutamide in rat and human liver slices was 0.019 mL/min and 3.16 mL/min, respectively. The intrinsic clearance of benzoic acid and tolbutamide was determined in rat hepatocytes and scaled to the whole liver using total number of cells in the rat liver. The CL(H) of benzoic acid and tolbutamide in rat hepatocytes was 3.55 ± 1.29 mL/min and 0.57 ± 0.16 mL/min, respectively. The CL(H) of benzoic acid and tolbutamide on intravenous dosing in the rat was 8.02 ± 1.01mL/min and 0.49 ± 0.06 mL/min, respectively. Precision cut liver slices under-estimated the CL(H) of benzoic acid and tolbutamide. The under-estimation is probably due to the inability of the drug to permeate the liver slice over the short time course of the initial rate experiments. The CL(H) of benzoic acid and tolbutamide in rats was better predicted by the IPRL and hepatocytes.

Styles APA, Harvard, Vancouver, ISO, etc.

22

Nowak, Urszula. « Rheumatoid factor production in response to liver damage ». Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=84065.

Texte intégral

Résumé :

Many liver diseases such as Alcoholic Liver Disease and Hepatitis C are associated with the production of autoantibodies. One of these autoantibodies is Rheumatoid Factor (RF), which binds to IgG and can aid in host defense. Since little is known about the role of RF in liver disease, we characterized the production of this autoantibody in three murine models of liver damage using alcohol, anti-Fas antibodies and carbon tetrachloride. RF was induced in response to chronic alcohol consumption as well as intraperitoneal injection of anti-Fas antibodies. RF was not produced in response to treatment with carbon tetrachloride for four weeks. Concurrent treatment with an E. coli glycolipoprotein which induces RF protected against liver damage as measured by a decrease in liver enzymes. Importantly, RF induced by this glycolipoprotein did not contribute to damage in the liver, suggesting that in the context of liver damage RF is not necessarily pathological.

Styles APA, Harvard, Vancouver, ISO, etc.

23

Magnusson, Rebecca. « Effects of litter quality and latitude on decomposition ». Thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-137763.

Texte intégral

Résumé :

Decomposition of organic material (litter) is an important part of the global carbon cycle. Environmental conditions, litter quality and the microbial community are the main factors affecting decomposition. The decomposition is divided into two phases, one fast initial phase and one slow second phase. The tea bag index (TBI) was used as a standardized method to measure decomposition rate along a latitudinal gradient. A common garden set up and extractions were made to determine the composition of the litter to investigate if climate or litter quality affected the decomposition rate. The result showed that the decomposition rate increased with higher latitude. The litter from higher latitude has more material that is easy to decompose. Natural litter abroad had higher decomposition rate than at home. On the contrary, standard litter at home had higher decomposition rate than abroad. This indicates that litter quality is more important than latitude. Further studies are needed with more sites along the gradient to conclude how climate and litter quality are affecting decomposition.

Styles APA, Harvard, Vancouver, ISO, etc.

24

Hicks, Julie Ann. « MicroRNAs in the spleen and liver of the developing chick embryo ». NCSU, 2007. http://www.lib.ncsu.edu/theses/available/etd-03252007-215944/.

Texte intégral

Résumé :

MicroRNAs are small (~19-24nt) non-coding RNAs that are involved in the regulation of gene expression. They are mainly expressed in development and many are expressed in a temporal as well as, a spatial manner. It is thought they may regulate up to 30% of all genes. Pyrosequencing using 454 Life Science technology is becoming the preferred method for microRNA profiling ad sequencing compared to the previous method of cloning and using traditional sequencing techniques. Use of 454 Life Sciences technology allows for a greater coverage of microRNAs and increases the chances of sequence low abundance microRNAs. In the current project we created four small RNA libraries from embryonic chick tissues, the spleen and liver at developmental time points E15 and E20. These libraries were then sequenced using 454 Life Sciences pyrosequencing. A total of 92,919 sequence reads were obtained, representing a total of 52,001 known chicken microRNAs. Of these 92,919 reads, 52,001 represented miRNAs matching the miRBase G. gallus database, and 3,472 were not found in the G. gallus database but were homologues of miRBase miRNAs from other species. Of these homologous reads 391 represented potential novel miRNAs. Other small RNAs, such as tRNA and rRNA, represented 24,672 of the reads, and 12,383 reads represented other types of sequences, such as degraded mRNA. More than one hundred different known miRNAs were identified in this study, and many were expressed in all four libraries. Common miRNAs that yielded multiple reads from all four libraries included miR-125b and miR-21, which are involved in general processes of cellular proliferation. Overall, the spleen libraries had a larger array of miRNAs than the liver libraries. Much of spleen development occurs during the later stages of embryonic development, so we can reasonably expect that many gene expression changes occur during these stages. As a result of this study, we identified nine potential novel chicken miRNAs. These novel miRNAs appear to be tissue-specific. The potential novel miRNAs appeared to be expressed at lower levels than some of the known miRNAs, which could indicate that most of the highly-expressed chicken miRNAs have already been identified, whereas, for the most part, the miRNAs expressed at low levels remain to be discovered.

Styles APA, Harvard, Vancouver, ISO, etc.

25

Brennan, Patricia Ann. « Access to liver transplantation : Gender, race and geographic disparities ». Diss., Search in ProQuest Dissertations & ; Theses. UC Only, 2008. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3324624.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

26

Crowley, Samuel Thomas. « Nonviral gene delivery to the liver ». Diss., University of Iowa, 2015. https://ir.uiowa.edu/etd/1577.

Texte intégral

Résumé :

Diseases of the liver have a large impact on human health. Genetic disorders, metabolic disorders, alcoholism, cancer, or infections can all impair liver function. If serious enough, a liver transplant may be necessary, a major surgical procedure which requires life-long immune suppression and relies on the availability of donor livers. Gene therapy is being intensively studied as a potential method to treat many disorders, including disorders of the liver. While viral gene therapy has seen some success, possible side effects make it risky, so nonviral gene delivery vectors are being developed. Unfortunately, these nonviral vectors do not yet have the efficiency of the viral vectors. Nonviral gene delivery vectors face many chges in vivo. The vectors must protect DNA from nucleases while it moves through the bloodstream, they must avoid nonspecific uptake, they must be enter the correct cells, and must enter the nucleus before the DNA can be expressed. If any step of this process fails, there will be very little, if any, expression, and it may be impossible to determine what went wrong. One impediment to nonviral gene delivery research is the transition from in vitro studies to in vivo studies. The cancer derived cell lines most often used for in vitro transfections are rapidly dividing, which makes nuclear entry much easier than in the whole animal. While primary cells would be a more accurate model of the in vivo environment, the number of cells that can be obtained from tissues is small, and primary cells usually cannot be cultured for long. This limits the number of experiments that can be done with each preparation of cells. To overcome this, we have miniaturized transfection assays, including the transfection of mouse primary hepatocytes with luciferase in 384 well plates. Because fewer cells are needed, more experiments can be performed with each liver preparation. Another issue introduced by the differences between in vitro and in vivo research is circulatory stability. In vitro, large particles with strong positive charges are desired, because they sink down onto the cells and are attracted to the negatively charged cellular membranes. However, in vivo these particles will aggregate serum proteins and become lodged in narrow capillary beds in the lungs or other organs, often causing toxicity. While this behavior can usually be overcome through PEGylation, improving a particle's circulatory half-life will still improve its chances of finding the correct target. Scavenger receptors found on liver nonparenchymal cells are very efficient at removing negatively charged particles from the bloodstream. We have shown that dosing large amounts of PEGylated polyacridine DNA polyplex can saturate the scavenger receptors and improve circulatory half-life. We have also shown that large doses of PEGylated peptide with or without acridine groups can inhibit scavenger receptor uptake through the formation of peptide-protein nanoparticles. By inhibiting scavenger receptor uptake, DNA can be successfully hydrodynamically stimulated at times up to 12 hours post-delivery, demonstrating a longer circulatory half-life and suggesting a mechanism to explain how delayed hydrodynamic stimulation can achieve full level gene expression in the liver after the DNA has had time to circulate throughout the whole animal. Once a nonviral vector finds its target cell, it must still enter the cell through endocytosis and then escape the endosome before it becomes digested in the lysosome. Before the DNA cargo can be expressed, it must enter the nucleus. Nuclear entry in nondividing cells is a major barrier to efficient gene delivery. One method to over come this barrier is to avoid the need for nuclear entry altogether by delivering mRNA instead of DNA. mRNA can produce protein in the cytoplasm by finding a ribosome and initiating translation. However, it is even less stable in the bloodstream than DNA. We have produced an mRNA construct capable of high-level expression in the liver through hydrodynamic delivery. The PEGylated polyacridine peptides used to protect DNA were applied to mRNA and shown to enhance expression, allowing a 1μg dose of mRNA peptide polyplex to produce higher expression than an equal dose of DNA. The peptides were also shown to provide some protection against nuclease digestion in serum. This suggests that efficient, if transient, protein expression can be achieved through peptide protected mRNA delivery. However, DNA delivery is still desired for longer term expression, and the nuclear entry of DNA is still a problem. In an effort to help facilitate nuclear entry, the membrane disrupting enzyme phospholipase A2 was modified in several ways. The enzyme was conjugated with DNA binding peptides, nuclear localization peptides, and hepatocyte targeting oligosaccharides. Additionally, mutant forms of the enzyme were prepared in bacterial expression systems to achieve site-specific conjugation. Unfortunately, none of these efforts produced a useful tool for nuclear entry. The research presented in this thesis represents some progress toward the goal of nonviral gene delivery to the liver. Hopefully, some of this work will be useful in the development of new treatments and therapies to improve human health.

Styles APA, Harvard, Vancouver, ISO, etc.

27

Southworth, Adam R. « Potential commercialization of a collagen-GAG scaffold for liver regeneration ». Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/45354.

Texte intégral

Résumé :

Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2008.
Includes bibliographical references (p. 63-65).
The potential for commercializing a scaffold made of collagen and glycosaminoglycan to help regenerate cirrhotic liver was analyzed and a business plan and model were created. Using a lypholization technique, a bulk-sized and highly porous scaffold is created. It is then inserted into the hole created by the excised liver scar tissue. By blocking contraction of the wound and mimicking the natural extracellular matrix, the scaffold induces regeneration of normal liver tissue. The in vivo approach is compared to several other experimental treatments of cirrhosis found in the literature. The difficulties that need to be addressed are explained and potential solutions are given. A cost model was created, incorporating equipment, labor, FDA, and raw material costs. This model was combined with information regarding the cost of current liver transplant procedures to create a profitable business plan based on the collagen-GAG scaffolds. A manufacturing and product sales business model was chosen due to the fairly low level of market competition and moderate barrier to entry. The intellectual property landscape is described and analyzed in terms of problematic existing patents and the potential for protecting the proposed scaffolds. A timeline for future research and development was created, with potential sources of funding during each phase. In addition to the current embodiment of the scaffold, possible changes to the scaffold properties and composition are proposed.
by Adam R. Southworth.
M.Eng.

Styles APA, Harvard, Vancouver, ISO, etc.

28

Opsitarevic, Izabella, et Scipe Ramadan. « En liten insats med stor betydelse ». Thesis, Malmö högskola, Fakulteten för hälsa och samhälle (HS), 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-25285.

Texte intégral

Résumé :

A QUALITATIVE STUDY ON THE EXPERIENCE OF ESCORT SERVICE UNDER THE ACT (SFS 1993:387) SUPPORT AND SERVICE FOR THE DISABLEDThe purpose of this study was to examine the experiences of escort service under the Act (SFS 1993:387) concerning Support and Service for the disabled (LSS) for self-determination, participation and equality of living conditions. In the results of this study appears that the escort service fulfills its role in breaking the isolation of persons with disabilities. It gives a picture of the escort service is much more than to break the isolation of people with disabilities. The aspects that emerges is that escort service gives persons with disabilities the opportunity to develop their independence, increase their self-esteem and broaden their frames of reference through increased participation in community life. All users report that they experience autonomy in the choice and order of activities within their grant initiatives. The result reveals that even the escorts feel that the users have the option to be able to determine their choice of activities. When it comes to concepts of self-determination, participation and equality of living conditions there is a certain ambiguity regarding the individual's definition of the various concepts as they can be experienced and perceived differently by different individuals. This makes it difficult to draw definitive conclusions about experience of escort service.Nyckelord: Delaktighet, Funktionshinder, Jämlikhet i levnadsvillkor, Ledsagarservice, Självbestämmande.

Styles APA, Harvard, Vancouver, ISO, etc.

29

Boyette, Keri Evelyn. « Characterization of Follistatin as a Candidate Gene for Litter Size in Pigs ». NCSU, 2005. http://www.lib.ncsu.edu/theses/available/etd-08032005-105553/.

Texte intégral

Résumé :

The objective of this study was to characterize follistatin (FOL) as a candidate gene for litter size in pigs. Litter size is a lowly heritable and sex-limited trait; therefore, response to selection may be enhanced by marker-assisted selection. Our approach for characterizing a region of SSC16, which includes FOL, was to utilize the candidate gene approach using type I and type II markers to determine if FOL had an association with the response to selection for increased litter size in the select line. Pigs genotyped were from a line selected for increased number of fully formed (FF) pigs and a contemporary control line. In generation nine, the estimated breeding value for litter size was 0.63 pigs greater in the select line than in the control line (Holl et al., 2003). A RFLP within FOL (n = 251) and the microsatellites, CGT27 (n = 224), S0363 (n=255), S0298 (n=260), and SW1661 (n=253) were genotyped. Effect of marker genotype on FF, number born alive (BA), number still born (SB), and number mummified fetuses (MUM) was tested. Data were analyzed by line with an animal model using MTDFREML. Fixed effects included year and marker genotype. In both the select and control lines, all markers had no significant affect on FF, BA, SB, or MUM when using the animal model. Therefore, follistatin is not likely to have a major effect on litter size in the population studied.

Styles APA, Harvard, Vancouver, ISO, etc.

30

Dong, Xin Min. « HCV-Core over-expressed specifically in liver cells ». Thesis, University of Ottawa (Canada), 2007. http://hdl.handle.net/10393/27834.

Texte intégral

Résumé :

Hepatitis C viruses (HCV) affect 170 million patients, but only a minority of patients develop symptoms and manage to clear the virus, and the pathogenesis remains unknown. Previous studies discovered that some viral proteins may suppress HCV specific T lymphocytes, leading to lower immune responses. Although many mouse models have been tried in laboratories worldwide, none of them mimicked natural Human HCV infection with individual HCV genes in vivo. To study the immunopathogenesis of HCV infections, we constructed some chimeric liver-specific vectors and one was selected to establish promoted mouse models, which express individual HCV genes specifically in the liver. In this research, the over-expression of HCV-Core and the cellular immune responses in mice driven by global and liver-specific promoters were also detected. Although the DNA injection needs to be optimized, our results indicate that liver-specific expression may provide a new way to elucidate the pathogenesis of HCV infections.

Styles APA, Harvard, Vancouver, ISO, etc.

31

Cawood, Ryan. « Liver specific microRNA control of adenovirus serotype five ». Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:d97d80b5-6272-4aab-b555-d03d0016eeff.

Texte intégral

Résumé :

MicroRNAs are small non-coding RNA molecules that regulate mRNA translation by binding to complementary sequences usually within the 3’ un-translated region (UTR). By inserting four perfectly complementary binding sites for the hepatic specific microRNA mir122 into the 3’ UTR of adenovirus wild type 5 (Ad5 WT) E1A mRNA I show that the acute liver toxicity caused by Ad5 WT in mice can be significantly reduced. This virus, termed Ad5-mir122, is a promising virotherapy candidate and causes no obvious liver pathology whilst maintaining Ad5 WT replication in mir122 negative cells. Data shows that repeat intravenous administration of Ad5-mir122 (2x1010vp) to HepG2 tumour bearing mice mediated significant anti-cancer efficacy. RT-QPCR for E1A mRNA demonstrated a 29-fold reduction when compared to Ad5 WT in murine liver whilst western blot confirmed that all E1A protein variants were knocked down. Viral genomic replication was also reduced in mouse liver by 25-fold compared to Ad5 WT. This control of virus activity reduced alanine and aspartate transaminase release by >15-fold and histological analysis showed little to no pathology in Ad5-mir122 infected livers. Measurement of mature mir122 levels in Ad5-mir122 infected livers by RT-QPCR showed that the quantity of mir122 remained unaffected at therapeutic doses. Complete genome mRNA array profiling of infected livers showed that the transcript levels of >3900 different mRNAs were changed more than 2-fold following Ad5 WT infection whilst less than 600 were changed by Ad5-mir122. A non-replicating control adenovirus vector altered >550 mRNAs. No known mir122 target mRNAs were affected following infection with Ad5-mir122. Western blot analysis of a known mir122 regulated target (Aldolase A) confirmed these results, demonstrating no change in protein level despite infection with Ad5-mir122. These data combined demonstrate that the exploitation of microRNA mir122 regulation to control adenovirus replication is a safe method of control and does not alter the endogenous level or activity of the microRNA or its endogenous mRNA targets. Ad5-mir122 is a potent anti-cancer agent that replicates to wild-type levels in microRNA mir122 negative cells but is specifically and safely attenuated in hepatocytes.

Styles APA, Harvard, Vancouver, ISO, etc.

32

Balko, Jody. « Use of Procalcitonin as a Biomarker of Bacterial Infection in Acute Liver Failure and Acute Liver Injury ». VCU Scholars Compass, 2012. http://scholarscompass.vcu.edu/etd/2744.

Texte intégral

Résumé :

Infections in patients with acute liver failure (ALF) and acute liver injury (ALI) are a frequent occurrence. Because ALF and ALI patients share many of the same clinical features as patients with severe sepsis and septic shock, identifying an infection based upon clinical manifestations is extremely difficult. Bacterial culture and sensitivity reports require 24 to 72 hours to be finalized after the need for a culture is suspected and obtained. During this time period, ALF and ALI patients are either not receiving required antibiotic therapy, receiving antibiotic therapy that is not required or not appropriate for the infecting bacterial pathogen, or receiving the correct antibiotic prophylaxis. Receiving an antibiotic that is not needed or inappropriate adds another level of complexity to the ALF and ALI patients because antibiotics may exacerbate liver dysfunction. The purpose of this study was to determine the utility of serum procalcitonin concentrations (SPCTC) as a biomarker of bacterial infections in patients with acute liver failure (ALF) and acute liver injury (ALI). This three part study measured SPCTC retrospectively on samples from ALF and ALI patients who were prospectively enrolled in the United States Acute Liver Failure Study Group (USALFSG) ALF and ALI studies. In the first part of the study, subjects were categorized according to how many SIRS continuum components they had and whether there was a documented infection. In the second part, serial samples on subjects who developed infections were identified. And, in the third part, serial samples on subjects diagnosed with infection on day one of the study and categorized based upon transplant free survival (TFS) or death and/or liver transplant (DoT) were identified. Procalcitonin was not found to be useful in identifying infection in the ALF and ALI patient populations. A cut-off for indication of infection was calculated to be 1.62 ng/mL using receiver operator curve (ROC) analysis. Despite the fact that there was an overall increase in SPCTC as the severity of illness increased in patients with a documented infection, there were confounding variables including antibiotic use, missing data, and small sample size that may have contributed to the poor sensitivity and specificity (0.643 and 0.620 respectively) calculated as part of the ROC analysis. SPCTC values appeared to be increased in subject with acetaminophen (APAP) toxicity and may have affected the cut-off, sensitivity, and specificity results. Increased SPCTC values were seen in APAP subjects who did not have a documented infection. It is unknown at this time if the SPCTC were increase due to liver damage, an undiagnosed infection, or as a result of increase cytokine production due to the APAP toxicity. Serial PCT concentrations in patients who achieved TFS showed a greater decrease over time than those of patients who died or received a liver transplant, however, the TFS group contained a large portion of APAP subjects. Further prospective studies are needed to determine the extent of interference with SPCTC in patients with APAP toxicity and to better define the PCT concentration cut-off between infection and no infection in the ALF and ALI populations.

Styles APA, Harvard, Vancouver, ISO, etc.

33

Williams, Zachary Thomas. « THE EFFECT OF USED BROILER LITTER ON THE GROWTH AND PERSISTENCE OF CAMPYLOBACTER ». MSSTATE, 2008. http://sun.library.msstate.edu/ETD-db/theses/available/etd-11072008-152607/.

Texte intégral

Résumé :

Litter is a possible source of Campylobacter colonization for broilers as well as contamination of crops when used as fertilizer. A survey of Arkansas broiler litter indicated that Campylobacter recovery rates were higher in pine shavings and rice hulls than sand. Two experiments utilized three types of litter, which were artificially contaminated with Campylobacter. After 24 hours no Campylobacter could be recovered from any sample. Campylobacter growth was also examined for used pine shaving litter in varying conditions: aerobic atmosphere, micro aerobic atmosphere (6% O₂), and moisture content. Campylobacter was recovered for all treatments at the initial sampling, and by the 12 hour sampling time, only the added moisture and micro aerobic atmosphere yielded recoverable Campylobacter. This research suggests that without birds present in the house to shed fresh Campylobacter cells onto the litter, that the litter itself is incapable of harboring the bacteria long enough to colonize sequential flocks.

Styles APA, Harvard, Vancouver, ISO, etc.

34

Ekstrand, Julia, et Vjolla Gasi. « Om vi litar på myndigheter, litar vi då också på varandra ? : En studie om förhållandet mellan socialt och institutionellt förtroende ». Thesis, Högskolan i Halmstad, Akademin för lärande, humaniora och samhälle, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-42975.

Texte intégral

Résumé :

Bo Rothstein redogör för att sambandet mellan den sociala tilliten och det institutionella förtroendet är starkt. Den teorin fortsätter Rothstein redogöra genom att enkelt förklara sambandet “litar vi tillräckligt på varandra som medborgare är sannolikheten stor att vi kommer lita på våra myndigheter och tvärtom”. Denna studie genomför en teoriprövning av Rothsteins samband, en prövning utifrån opinionsmätningar som svarar på hur medborgare förlitar sig på välkända myndigheter och andra medborgare i samhället. De utvalda myndigheterna för undersökning är; Polismyndigheten, Migrationsverket, Försäkringskassan, Arbetsförmedlingen och Skatteverket. Studien genomför en kvantitativ teoriprövning med empiriskt material från sekundär datainsamling inhämtad från SOM-Institutet. Det sluttgilitga resultatet resulterar för att sammbandet har slutat fungera, vi kan inte konstatera att den sociala tilliten hör samman med det institutionella förtroendet, eller tvärtom. Detta konstruerade vidare hypoteser på varför sambandet kan ha slutat fungera eller vad som berör att sambandet inte gick att redovisa i denna studie.

Styles APA, Harvard, Vancouver, ISO, etc.

35

Brand, Jonathan Frieman. « Staging Liver Fibrosis with Statistical Observers ». Diss., The University of Arizona, 2016. http://hdl.handle.net/10150/612941.

Texte intégral

Résumé :

Chronic liver disease is a worldwide health problem, and hepatic fibrosis (HF) is one of the hallmarks of the disease. Pathology diagnosis of HF is based on textural change in the liver as a lobular collagen network that develops within portal triads. The scale of collagen lobules is characteristically on order of 1mm, which close to the resolution limit of in vivo Gd-enhanced MRI. In this work the methods to collect training and testing images for a Hotelling observer are covered. An observer based on local texture analysis is trained and tested using wet-tissue phantoms. The technique is used to optimize the MRI sequence based on task performance. The final method developed is a two stage model observer to classify fibrotic and healthy tissue in both phantoms and in vivo MRI images. The first stage observer tests for the presence of local texture. Test statistics from the first observer are used to train the second stage observer to globally sample the local observer results. A decision of the disease class is made for an entire MRI image slice using test statistics collected from the second observer. The techniques are tested on wet-tissue phantoms and in vivo clinical patient data.

Styles APA, Harvard, Vancouver, ISO, etc.

36

Wadhwani, Ranjeeta. « Cause and Prevention of Liver Off-Flavor in Five Beef Chuck Muscles ». DigitalCommons@USU, 2008. https://digitalcommons.usu.edu/etd/149.

Texte intégral

Résumé :

Liver off-flavor is a sporadic problem that limits the consumer acceptance of several beef chuck muscles, including the infraspinatus (flat iron steak). Residual blood hemoglobin is known to contribute to liver off-flavor development. This study was conducted to evaluate factors affecting development of liver off-flavor after cooking of beef chuck (shoulder) muscles. The study was conducted in three parts. The objective of part 1 was to determine effects of muscle (infraspinatus, longissimus dorsi, serratus ventralis, supraspinatus, teres major) and processing (with or w/o carcass electrical stimulation) on residual blood hemoglobin content and total pigment content of raw muscle and sensory characteristics after cooking to 71 or 82?C. The objective of part 2 was to evaluate the effect of antioxidant treatment and anaerobic packaging to possibly reduce the incidence of liver and other off-flavors of beef infraspinatus (IF) steaks. The objective of part 3 was to determine the effect of animal age (commercial grade; >42 months, compared to select grade; <30>months), antioxidant treatment, and anaerobic packaging on sensory characteristics of beef IF steaks. Among beef chuck muscles, the infraspinatus had highest mean liver flavor score of 2.08±1.00 where 2=slightly intense liver flavor. Other muscles (longissimus dorsi, serratus ventralis, supraspinatus, teres major) had mean liver flavor scores less than 2. Liver flavor score, myoglobin, hemoglobin, and total pigment content were higher (p<0.05) for infraspinatus muscle from older animals. Among select grade muscles, carcass electrical stimulation had no significant effect on liver flavor score. Rancid flavor scores were significantly increased from 1.34±0.65 to 1.58±0.84 as internal cook temperature increased from 71 to 82°C but mean TBA values as a measure of rancidity (0.25±0.15 and 0.29±0.13, respectively) were not affected by cook temperature. Antioxidant treatment significantly reduced TBA values, rancid, and liver flavor scores for aerobically packaged steaks (PVC or 80% O2-MAP) but had little effect on scores of steaks in anaerobic packaging (0.4% CO-MAP). Results of this study indicate that infraspinatus steaks from older animals are most likely to have objectionable liver, sour/grassy, or rancid flavors. Objectionable flavor scores were lower in steaks receiving antioxidant injection or packaged anaerobically in 0.4% CO-MAP.

Styles APA, Harvard, Vancouver, ISO, etc.

37

Thoman, Heather Marie. « A Critical Temperature Threshold for Early Leaf Litter Decomposition and Microbial Enzyme Activity ». University of Toledo / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1399571419.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

38

Bondesson, Ida, et Ida Rovin. « Lite historia rensar magen ». Thesis, Malmö högskola, Lärarutbildningen (LUT), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-28111.

Texte intégral

Résumé :

Vi har valt att göra vårt examensarbete i form av ett utvecklingsarbete där ett ämnesövergripande projekt har planerats och genomförts. Utgångspunkten för projektet har varit SVT:s “Historieätarna”. Syftet har varit att undervisa utifrån “den lilla historien” för att fördjupa elevers historiemedvetande och historiska intresse samt att levandegöra historien genom att låta eleverna laga och äta mat från 1800-talets Sverige. De ämnen vi har valt att förena är det teoretiska ämnet historia och det mer praktiskt orienterade ämnet hem- och konsumentkunskap. Genom intervjuer med lärare, observation av lektioner och elevenkäter har vi undersökt vilken nytta man kan dra av ett projekt som vårt. Projektet genomsyras av begreppen “den lilla historien”, historiemedvetande och intresse. Resultatet visar att både lärare och elever gagnas av ämnesövergripande arbete i skolan förutsatt att man är villig och har möjlighet att lägga tid på det. Att anlägga ett underifrånperspektiv på historieundervisningen och att utgå ifrån ”den lilla historien” och elevens vardag då man undervisar i historia visar sig vara ett bra upplägg för elever då det är lättare att förstå stora sammanhang om man börjar i någonting man redan känner till.

Styles APA, Harvard, Vancouver, ISO, etc.

39

Weens, William. « Mathematical modeling of liver tumor ». Phd thesis, Université Pierre et Marie Curie - Paris VI, 2012. http://tel.archives-ouvertes.fr/tel-00779177.

Texte intégral

Résumé :

Comme démontre récemment pour la régénération du foie après un dommage cause par intoxication, l'organisation et les processus de croissance peuvent être systématiquement analyses par un protocole d'expériences, d'analyse d'images et de modélisation [43]. Les auteurs de [43] ont quantitativement caractérise l'architecture des lobules du foie, l'unité fonctionnelle fondamentale qui constitue le foie, et en ont conçu un modèle mathématique capable de prévoir un mécanisme jusqu'alors inconnu de division ordonnée des cellules. La prédiction du modèle fut ensuite validée expérimentalement. Dans ce travail, nous étendons ce modèle a l'échelle de plusieurs lobules sur la base de résultats expérimentaux sur la carcinogène dans le foie [15]. Nous explorons les scénarios possibles pouvant expliquer les différents phénotypes de tumeurs observés dans la souris. Notre modèle représente les hépatocytes, principal type de cellule dans le foie, comme des unités individuels avec un modèle a base d'agents centré sur les cellules et le système vasculaire est représenté comme un réseau d'objets extensibles. L'équation de Langevin qui modélise le mouvement des objets est calculée par une discrétisation explicite. Les interactions mécaniques entre cellules sont modélisées avec la force de Hertz ou de JKR. Le modèle est paramètre avec des valeurs mesurables a l'échelle de la cellule ou du tissue et ses résultats sont directement comparés avec les résultats expérimentaux. Dans une première étape fondamentale, nous étudions si les voies de transduction du signal de Wnt et Ras peuvent expliquer les observations de [15] où une prolifération instantanée dans les souris mutées est observée seulement si 70% des hépatocytes sont dépourvues d'APC. Dans une deuxième étape, nous présentons une analyse de sensibilité du modèle sur la rigidité de la vasculature et nous la mettons en relation avec un phénotype de tumeur (observe expérimentalement) où les cellules tumorales sont bien différentiées. Nous intégrons ensuite dans une troisième 'étape la destruction de la vasculature par les cellules tumorales et nous la mettons en relation avec un autre phénotype observe expérimentalement caractérise par l'absence de vaisseaux sanguins. Enfin, dans la dernière étape de notre étude nous montrons que des effets qui sont détectables dans les petits nodules tumoraux et qui reflètent les propriétés des cellules tumorales, ne sont plus présents dans la forme ou dans le phénotype des tumeurs d'une taille excédant la moitié de celle d'un lobule.

Styles APA, Harvard, Vancouver, ISO, etc.

40

Tzimas, George N. « Proprotein convertase 1 and 2 profiles in human liver colorectal metastases ». Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=80889.

Texte intégral

Résumé :

The family of proprotein convertases has been recently implicated in tumorigenesis and metastasis in animal models. However, these studies have not yet been completely corroborated in human tumors. Here, we show that mRNA, protein expression, and protein cleavage profiles of proprotein convertases 1 and 2 are altered in liver colorectal metastasis, compared to unaffected and normal liver. Active PC1 is overexpressed in tumor, correlating with its mRNA profile. Moreover, the enhanced PC2 processing pattern in tumor correlates with the overexpression of its specific chaperone 7B2, which in turn may represent a target for early diagnosis and treatment. The increased PC2 maturation, as well as the overexpression and altered processing of PC1 may be either a cause or a consequence for the observed metastasic phenotype. Nevertheless, they may result in the alteration of the secretory pathway, which could therefore, modify the cellular microenvironment and thus favor tumor growth and/or metastasis.

Styles APA, Harvard, Vancouver, ISO, etc.

41

Barnes, Mark Aaron Jr. « MACROPHAGE MIGRATION INHIBITORY FACTOR AND LIVER DISEASE : THE ROLE OF MIF IN ALCOHOL-INDUCED LIVER INJURY AND CARBON TETRACHLORIDE (CCI4)-INDUCED LIVER FIBROSIS ». Case Western Reserve University School of Graduate Studies / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=case1396429556.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

42

Kammula, Rao Karunakara. « Purification, characterization and inhibitor studies of rat liver nuclear spermidine N-acetyltransferase ». Scholarly Commons, 1994. https://scholarlycommons.pacific.edu/uop_etds/2783.

Texte intégral

Résumé :

Polyamines are ubiquitously present in all living cells. The abnormal metabolism of polyamines that is associated with certain types of cancers has been the focus of several investigations. Enzymes that are involved in the transacetylation of polyamines have been studied extensively, so as to develop inhibitors of these enzymes which may be used as drugs in cancer therapy. Based on indirect evidence, the nuclear spermidine acetyltransferase has been thought to be a critical enzyme that is associated with genetic derepression leading to cancerous growth. In the present study a novel, rapid, sensitive and highly reproducible radio chemical procedure has been developed for assaying spermidine (polyamine) acetylation. The study contains data showing range of linearity of the procedure, percent product recovery, as well as low interference from the unreacted acetyl coenzyme A. Rat liver nuclear spermidine acetyltransferase has been purified using the biochemical procedures annmonium sulfate precipitation, DEAE chromatography, Hydroxyapatite chromatography, Diaminobutyl agarose chromatography and Polyacrylamide P-300 gel filtration. The enzyme obtained at the end of such procedures was found to be essentially homogeneous as seen on native gel electrophoresis. The purified enzyme has been shown to have an isoelectric point of 5.2. Bicine and Hepes were found to be more suitable as buffering species for good enzyme activity. The enzymatic reaction velocity was found to increase with temperature upto 36$\sp\circ$C and was found to increase linearly up to four minutes under non limiting conditions in the presence of 20% glycerol. Using the purified enzyme it has also been established that of the three nuclear polyamines, spermidine is the preferred substrate. The apparent Km for acetyl Co A with spermidine as substrate was found to be about 5 mM. The purified enzyme does acetylate histones. All the substrate analogs containing aminobutylamino group are acetylated by the enzyme.

Styles APA, Harvard, Vancouver, ISO, etc.

43

Sharpe, Amy-Joan Lorna 1965. « Substrate specificity of rat liver aldehyde dehydrogenase with chloroacetaldehydes ». Thesis, The University of Arizona, 1991. http://hdl.handle.net/10150/277906.

Texte intégral

Résumé :

Chlorinated acetaldehydes have recently been the focus of research due to their role as reactive intermediates and their possible occurrence in chlorinated drinking water. The metabolism of these compounds, however, has not been extensively studied. In this study, the in vitro substrate specificity of cytosolic and mitochondrial rat liver aldehyde dehydrogenase toward these compounds was investigated. Both crude and semi-purified preparations of the enzymes were used. Monochloroacetaldehyde was found to be extensively metabolized by this enzyme system. It was metabolized to a greater extent than the standard compound propionaldehyde. Dichloroacetaldehyde was also found to be metabolized by this enzyme, but to a lesser extent than its monochloro-analogue. There was some evidence to suggest, however, that alcohol dehydrogenase and chloral hydrate dehydrogenase may play a significant role in the metabolism of this compound. Chloral hydrate was not metabolized by this enzyme to an appreciable extent.

Styles APA, Harvard, Vancouver, ISO, etc.

44

Skoug, Olof, et Alf Nilsson. « ARBETSLAG ? ETT LITET SLAG Fyra gymnasielärares attityder till arbetslag ». Thesis, Malmö högskola, Lärarutbildningen (LUT), 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-35996.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

45

Wang, Renze S. M. Massachusetts Institute of Technology. « Numerically generating topology of the liner finish in internal combustion engines ». Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/101853.

Texte intégral

Résumé :

Thesis: S.M., Massachusetts Institute of Technology, Department of Materials Science and Engineering, 2015.
Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2015.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 74-77).
Internal combustion (IC) engines are broadly utilized today. The friction caused by piston rings in IC engines contributes around 20% of the mechanical friction losses. The liner finish is the most critical parameter to define the tension and other design parameters of the piston rings for proper sealing. This work is focused on developing numerical approaches to generating liner finishes based on certain values of topology parameters. The generated surface is able to simulate the lubrication and dry contact behaviors of the original surface, so that the method is used to study the effects of various topology parameters on friction losses. First, methods to analyze, generate, test, and compare honed liner surfaces have been developed. The algorithm to analyze the topology parameters of honed surfaces is described. The honed surfaces are numerically generated and compared with the experimental data. Moreover, the topological variables are changed and the corresponding friction behaviors are studied. The relations between topology variables and friction losses are illustrated. We also developed a quantitative relation between two ISO standards describing the honed liner finish, so that the manufacturing industry can use the surface generation method in convenience. Second, attempts were made to simulate the break-in processes for honed liner finish. Measured and numerically generated surfaces are simulated and compared. The friction and pressure behaviors for lightly and heavily worn surfaces are compared with experimental data. Moreover, by tuning the worn parameters, the friction effective mean pressure (FMEP) curve can match the experimental data. Finally, the algorithm to numerically generate thermally sprayed liner finish is described. The hydrodynamic and dry contact friction behaviors for generated surfaces are compared with experimental data. Critical topology parameters are tuned and their effects on friction losses are studied. Moreover, the effects of the pores created by the plasma spraying processes on the lubrication behaviors are simulated.
by Renze Wang.
S.M.

Styles APA, Harvard, Vancouver, ISO, etc.

46

Simmons, Jason. « Influence of Poultry Litter on Dark Tobacco Growth and Soil Nutrient Availability ». TopSCHOLAR®, 2004. http://digitalcommons.wku.edu/theses/516.

Texte intégral

Résumé :

Due to the relatively high value of dark tobacco compared with fertilizer costs, nitrogen is recommended at levels as high as 338 kg ha"1. Such rates of inorganic fertilizers increase the osmotic pressure of the soil solution and soil acidity, often causing reduced stands, Mn toxicity, Mo and Ca deficiencies, and reduced yield and quality of the cured leaf (Sims et al., 1984). Poultry litter utilized as a nutrient source is an inexpensive alternative to this dilemma due to its relatively neutral or alkaline composition. However, due the amount of chloride present in poultry litter, the University of Kentucky advises that application be limited to a maximum of 9 Mg ha"1 (Wells, 1996). Environmental concerns such as nitrate contamination of groundwater, P runoff into surface water, and accumulation of heavy metals in the soil are often related to excessive application of poultry litter. Studies were conducted at Western Kentucky University's Agricultural Research and Education Complex in Bowling Green, Kentucky and a farm in Owensboro, Kentucky to evaluate the influence of poultry litter on dark tobacco growth and soil nutrient concentrations. Results from these studies indicate that when applied at recommended rates, poultry litter in most cases can alleviate soil acidification often associated with the use of inorganic fertilizer sources. In general, poultry litter amendments increased soil pH, while inorganic fertilizers had the opposite effect. Data from the Rate Study suggests that rate of inorganic fertilizer and soil pH are negatively correlated. Due to the high nutrient content of poultry litter, its utilization could possibly lead to an accumulation of P2O5 and certain heavy metals, such as Cu and Zn. Data from the Bowling Green Timing Study indicated that poultry litter amendments increased postharvest soil P availability compared to inorganic fertilizer amendments. At the Owensboro location there were no differences in soil P availability among treatments. Results from the Rate Study suggest that soil P availability and poultry litter rate were positively correlated. Data from all studies indicate that in some cases, soil Cu availability was greater in poultry litter treated plots than in plots treated with inorganic fertilizers. With one exception, plots receiving poultry litter were higher in soil Zn availability than inorganic fertilizer plots at the Bowling Green Timing Study. Data from the Rate Study suggests that increasing the poultry litter rate increased soil Zn availability in poultry litter plots receiving a sidedress application. Data from the Owensboro Timing Study indicated that regardless of application timing, cured lamina tissue chloride concentration in poultry litter amended plots were greater than the tobacco industry standard of 1%. Chloride concentrations in the lamina and stem were higher in plots receiving poultry litter than plots treated with inorganic fertilizers. Despite these concentrations there were no noticeable differences in curing and USDA quality rating. Data from the Timing Studies indicated that total yields were equivalent in poultry litter and inorganic fertilizer treated plots, however yields of certain grades did vary. Plots receiving a source of fertilizer had higher total yields than the untreated control. Results from the Rate Study showed that total yields were quite variable, which may be attributed to poor water drainage from the study area. In the Rate Study, a general trend emerged in which increasing the rate of poultry litter in combination with a sidedress application increased trash, lug, and total yield, but decreased tip yield.

Styles APA, Harvard, Vancouver, ISO, etc.

47

Wang, Jian 1961. « Role of tumor-hepatocyte adhesion in carcinoma cell metastasis to the liver ». Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=40275.

Texte intégral

Résumé :

Cell adhesion molecules (CAM) have been implicated in the process of cancer metastasis. However, the interactions of metastatic tumor cells with organ parenchymal cells-hepatocytes particularly the relevance of tumor-cell-hepatocyte adhesion to liver metastasis is still not fully understood. We have investigated the role of tumor cell-hepatocyte interaction in liver metastasis using liver metastatic subline H-59 of the Lewis lung carcinoma. A monoclonal antibody (MAb) C-11 was produced which was highly specific to liver metastatic H-59 cells. Our in vitro studies showed that this MAb and its F(ab)2 fragments could block tumor H-59 cell adhesion to hepatocytes. The molecule detected by MAb C-11 on H-59 cells as well as on hepatocytes was a 64-71 kDa plasma membrane glycoprotein (designated C-11 BP). We found that this molecule contains approximately 43% of N-linked carbohydrates which were not involved in MAb C-11 recognition, but participated in the adhesion process. MAb C-11 could also block the stimulatory effect of hepatocytes on tumor cell proliferation indicating that the adhesion of H-59 cells to hepatocytes may be necessary for tumor cell growth. The in vivo role of the C-11 BP was subsequently tested and it was shown that MAb C-11 and its F(ab)2 fragments could significantly reduce the number of hepatic metastases when used to pretreat H-59 cells before intrasplenic injection, or when inoculated directly into the animals by the intraperitoneal and intravenous routes. This inhibitory effect resulted in an increase in the survival time of tumor-inoculated mice. In additional studies, a second molecule namely the membrane-associated endoplasmic reticulum protein ERp-72 was also implicated in the adhesion of H-59 cells to the hepatocytes, however its role in vivo remains to be confirmed. Our results suggest that CAM involved in tumor-hepatocyte adhesion play an important role in liver metastasis. Monoclonal antibody against tumor cell surface adhesion molecul

Styles APA, Harvard, Vancouver, ISO, etc.

48

Pearlman, Jef 1977. « SLS-Lite : enabling spoken language systems design for non-experts ». Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/86832.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

49

Ghali, Maged. « Implications of preoperative pulmonary function testing for post liver transplant outcomes ». Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=18802.

Texte intégral

Résumé :

ABSTRACT Pulmonary complications are common post-transplant and may lead to increased mortality. Pulmonary function tests (PFTs) are routinely obtained preoperatively, but their usefulness in liver transplantation is unknown. The objective of this study was to assess the impact of preoperative PFTs on postoperative pulmonary complications (PPCs), ICU stay, and death post-liver transplant. This single site historical cohort study encompassed all 531 liver transplants performed in 462 patients at the Royal Victoria Hospital through June 30, 2006. Outcomes included death, PPCs, and length of intubation and ICU stay. Independent variables including PFTs, age, gender, race, smoking history, etiology of liver disease, MELD score, and ischemia time were used in logistic regression and Cox proportional hazards models to assess their impact on the outcomes listed above. 205 patients had complete PFT data. Decreased total lung capacity (TLC) was a predictor of increased length of ICU stay, duration of intubation, and mortality. A 10% decrease in TLC increased the mortality risk by 43%. Increased residual volume (RV), cold ischemia time, and age were predictors of mortality. Predictors of prolonged ICU stay or intubation were TLC, MELD score, male gender and cold ischemia time. PFTs were not significant predictors of PPCs. PFTs do not predict pulmonary complications but predict length of ICU stay and intubation, as well as mortality. PFTs may reflect the severity of underlying liver disease as well as intrinsic lung disease.
RÉSUMÉ Les complications respiratoires sont fréquentes après les greffes et peuvent amener un taux accru de mortalité. Les tests de fonction pulmonaire sont maintenant obtenus régulièrement en phase pré-opératoire. Cependant, leur pertinence dans les cas de greffes hépatique est inconnue. Le but de cette étude est d'évaluer la capacité de prédiction des tests de fonction pulmonaire pré-opératoires sur les complications post-opératoires, la durée de séjour aux soins intensifs et les risques de mortalité post-greffe hépatique. Cette étude rétrospective fut menée à un site de référence pour les greffes hépatiques, soit l'Hôpital Royal Victoria. Nous avons révisé toutes les opérations (531) qui furent effectués chez 462 patients jusqu'au 30 juin 2006. Nous avons considéré les décès, les complications pulmonaires, ainsi que la durée d'intubation et la durée de séjour aux soins intensifs en tant que variables dépendants. Les facteurs prédictives étaient des tests de fonction pulmonaire, l'âge, le sexe, l'origine ethnique, l'histoire de tabagisme, le type de maladie hépatique sous-jacent, le score MELD et le temps ischémique de la greffe. Nous avons utilisé des modèles de régression logistique et de Cox afin d'évaluer la capacité prédictive indépendante des tests de fonction pulmonaire ainsi que des autres variables. 205 patients avaient des données complètes de leurs tests de fonction respiratoire en pré-opératoire. Une réduction dans la capacité pulmonaire totale étant associée de façon significative à la durée de séjour aux soins intensifs, ainsi qu'une durée accrue d'intubation et à un taux accru de mortalité. Ainsi, une diminution de 10% dans la capacité pulmonaire totale respiratoire en pré-opératoire était associée de façon indépendante à une augmentation de 43% du risque de mortalité. Une augmentation du volume résiduel, ainsi qu'une augmentation du temps ischémique et

Styles APA, Harvard, Vancouver, ISO, etc.

50

Kirchner, John P. « A Method for the Application of Computer Analytic Tools to Clinical Research : Neural Networks Analysis of Liver Function Tests to Assist in the differential Diagnosis of Liver Disease ». NSUWorks, 1997. http://nsuworks.nova.edu/gscis_etd/638.

Texte intégral

Résumé :

There is a great deal of effort by medical educators in the instruction of the use of computers for clinical practice but little training in the methods and utility of computer applications in clinical research. In this paper I present a method for the application of computer analytic tools to clinical research. The steps described lead the student through the standard clinical research process and demonstrate the decision making that must take place in each step of any clinical research program. This example is based upon a valid and unique research question relating to my particular field of medical hepatology. Liver disease represents a significant cause of morbidity and mortality throughout the world. In order to significantly reduce the impact of liver disease it is essential that such disorders be recognized with great accuracy early on in their course. The diagnosis of liver disease is frequently difficult and expensive even for specialists in this area. Standard liver function tests have the potential of assisting the physician as accurate, reliable, inexpensive, and easily accessible tools for the differential diagnosis of liver disease. However, the current applications of liver function tests for this purpose offer only limited value to the clinician in terms of reliability and validity. Clinical research efforts aimed at improving upon the precision of liver function tests through such techniques as test panels, test ratios, multivariate statistical methods and the applications of traditional expert systems have all had limited success and acceptance. The research described in this paper has resulted in the development of a probabilistic neural network program that was able to classify 109 sets of liver function tests into one of eighteen possible diagnostic categories with a precision of over 90%. The neural network developed as a result of this research should serve as an efficient tool for the clinician in the management of patients with liver disease. It should also act as a stimulus for further research in the application of neural network tools to clinical medical research.

Styles APA, Harvard, Vancouver, ISO, etc.

Thèses sur le sujet « Science liter »

Créez une référence correcte selon les styles APA, MLA, Chicago, Harvard et plusieurs autres