Letteratura scientifica selezionata sul tema "Pre-coagulation"
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Articoli di riviste sul tema "Pre-coagulation"
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Dave, Rutvi, Amit Agravat, Gauravi Dhruva e Ankita Katara. "Comparative Study if Coagulation Factors in Pre-Eclampsia and Normal Pregnancy". International Journal of Scientific Research 3, n. 4 (1 giugno 2012): 377–78. http://dx.doi.org/10.15373/22778179/apr2014/135.
Testo completo
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Rukapan, Weerapong, Benyapa Khananthai, Thirdpong Srisukphun, Wilai Chiemchaisri e Chart Chiemchaisri. "Comparison of reverse osmosis membrane fouling characteristics in full-scale leachate treatment systems with chemical coagulation and microfiltration pre-treatments". Water Science and Technology 71, n. 4 (19 novembre 2014): 580–87. http://dx.doi.org/10.2166/wst.2014.468.
Testo completoAbstract (sommario):
Fouling characteristics of reverse osmosis (RO) membrane with chemical coagulation and microfiltration (MF) pre-treatment were investigated at full-scale leachate treatment systems. In chemical coagulation pre-treatment, solid separation from stabilized leachate was performed by ferric chloride coagulation followed by sand filtration. Meanwhile, MF pre-treatment and the RO system utilized direct filtration using a 0.03 µm membrane without chemical addition. MF pre-treatment yielded better pollutant removals in terms of organics and nitrogen. The study on effect of pre-treatment on RO membrane fouling revealed that accumulated foulant on the RO membrane in MF pre-treatment was significantly lower than that of chemical coagulation. Nevertheless, NaOH cleaning of the fouled RO membrane after chemical coagulation pre-treatment could better recover its permeate flux, thus suggesting that the formation of a loose-structure cake layer by chemical coagulation pre-treatment could allow effective penetration of chemical cleaning and detachment of foulant layer from the membrane surface.
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Kanazawa, Akishige, Tadashi Tsukamoto, Sadatoshi Shimizu, Shintaro Kodai, Sadaaki Yamazoe, Go Ohira, Takayoshi Nakajima, Kiyohide Kioka, Yasuko Kawasaki e Takashi Nakai. "Evolution of laparoscopic liver resection using microwave pre-coagulation and soft-coagulation system". Journal of Microwave Surgery 30 (2012): 133–38. http://dx.doi.org/10.3380/jmicrowavesurg.30.133.
Testo completo
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Zhang, H. Y., Y. C. Zhao e J. Y. Qi. "Treatment of biologically treated leachate by oxidation and coagulation". Water Science and Technology 64, n. 7 (1 ottobre 2011): 1413–18. http://dx.doi.org/10.2166/wst.2011.377.
Testo completoAbstract (sommario):
This work aims to investigate removal efficiency of oxidation and coagulation/flocculation processes, to provide an effective method for the treatment of biologically pre-treated leachate. Leachate containing 985 mg L−1 COD was treated by using three treatment schemes, i.e. oxidation, coagulation/flocculation and the combined process of coagulation/flocculation followed by oxidation. The application of single oxidation resulted in the effective removal of COD and color up to 80.4 and 83.2%, respectively. However, residual COD values lower than 200 mg L−1 could only be achieved under intensive experimental conditions (high dosage of Ca(ClO)2 and prolonged oxidation time). Coagulation/flocculation yielded residual COD values higher than 200 mg L−1 even at the optimum coagulation conditions. The combined treatment by coagulation/flocculation followed by oxidation yielded final COD lower than 100 mg L−1 at the following conditions: pre-coagulation with 250 mg L−1 PFS (poly-ferric sulfate) and over 30-min post-oxidation, or pre-coagulation with 300 mg L−1 PFS and over 20-min post-oxidation. Hence, pre-coagulation with PFS followed by oxidation with Ca(ClO)2 was recommended for advanced treatment of biologically treated leachate.
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TAKAOKA, Masaki, Junichi HIROTA, Nobuo TAKEDA e Takeshi FUJIWARA. "Anaerobic Digestion of Sewage Sludge from Pre-Coagulation." Doboku Gakkai Ronbunshu, n. 685 (2001): 17–26. http://dx.doi.org/10.2208/jscej.2001.685_17.
Testo completo
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Tsuchiya, Masaru, Yuichiro Otsuka, Tetsuya Maeda, Jun Ishii, Yoshihisa Kubota, Akira Tamura e Hironori Kaneko. "The safety laparoscopic hepatectomy using pre-coagulation technique". Journal of Microwave Surgery 29 (2011): 85–89. http://dx.doi.org/10.3380/jmicrowavesurg.29.85.
Testo completo
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Kabsch-Korbutowicz, Malgorzata. "Impact of pre-coagulation on ultrafiltration process performance". Desalination 194, n. 1-3 (giugno 2006): 232–38. http://dx.doi.org/10.1016/j.desal.2005.09.031.
Testo completo
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Barker, P., e C. C. Callander. "Coagulation screening before epidural analgesia in pre-eclampsia". Anaesthesia 46, n. 1 (gennaio 1991): 64–67. http://dx.doi.org/10.1111/j.1365-2044.1991.tb09322.x.
Testo completo
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Trotter, T. N., J. K. Wood, A. L. Armstrong e A. E. May. "Coagulation screening before epidural analgesia in pre-eclampsia". Anaesthesia 46, n. 7 (luglio 1991): 596. http://dx.doi.org/10.1111/j.1365-2044.1991.tb09682.x.
Testo completo
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Flower, D. R., G. Pineau des Forêts e C. M. Walmsley. "Freeze-out and coagulation in pre-protostellar collapse". Astronomy & Astrophysics 436, n. 3 (giugno 2005): 933–43. http://dx.doi.org/10.1051/0004-6361:20042481.
Testo completoTesi sul tema "Pre-coagulation"
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Chung, Kyung Sun. "Membrane Distillation for Leachate Treatment with Fenton Pre-Coagulation Treatment Process". Thesis, Virginia Tech, 2020. http://hdl.handle.net/10919/96701.
Testo completoAbstract (sommario):
Landfill leachate is considered as a complex wastewater with various organic and inorganic species which must meet strict discharge standards before its release. Due to such high concentration of diverse pollutants, leachate is low in biodegradation; therefore, a proper usage of physicochemical treatments is required. In this study, membrane distillation (MD) has been used along with Fenton treatment process for pre-coagulation to achieve an effective removal of contaminants. MD is a technology derived with vapor pressure difference across the hydrophobic membrane which traps the feed-wastewater vapor at the entrance of the hydrophobic side before permeation. In order to modify and assist in membrane technology's common drawback, which is dealing with foulants, Fenton oxidation is coupled in the leachate treatment process. Fenton is reserved to be the most effective for leachate treatment and is widely used due to its simple operation and low costs. Fenton oxidation was able to lessen the chemical oxygen demand (COD) concentration of leachate up to 55% while increasing the conductivity and reducing the concentration of NH4-N. The membrane flux and volume had a significant increase with a use of lower COD leachate after Fenton treatment coupled with MD.Master of Science
Landfilling has been recognized as a principal disposal process of municipal solid wastes globally over the past decades, and this disposal method has been one of the leading concerns for a continuous production of landfill leachate. Leachate is considered as a complex wastewater with a variety of organic and inorganic species which must meet strict discharge standards before its release. Due to such high concentration of diverse pollutants, leachate is low in biodegradation; therefore, a proper usage of physicochemical treatments is required. In this study, membrane distillation (MD) has been used along with Fenton treatment process for pre-coagulation to achieve an effective removal of contaminants. MD is a technology derived with vapor pressure difference across the hydrophobic membrane which traps the feed-wastewater vapor at the entrance of the hydrophobic side before permeation. MD has several advantages which include reduced operating temperature compared to conventional distillation processes, fewer requirements of membrane cleaning, and lower operating hydraulic pressure than other conventional pressure-driven membrane processes such as reverse osmosis (RO). This technology has a common drawback along with other membrane-required technologies which is dealing with foulants. For a reduction in membrane fouling, Fenton oxidation is coupled in the leachate treatment process. Fenton is reserved to be the most effective for leachate treatment and is widely used due to its simple operation and low costs.
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Guerrieri, Diane. "Pilot plant study on the formation of bromate during pre-coagulation ozonation". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0030/MQ62215.pdf.
Testo completo
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Al-Abri, Mohammed Z. "Combined macromolecular adsorption and coagulation for improving pre-treatment of membrane processes in desalination plants". Thesis, University of Nottingham, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.446383.
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Tranchant, Carol Claude. "Coagulation behaviour of differently acidified and renneted milk and the effects of pre-treatment of milk". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0022/NQ51049.pdf.
Testo completo
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Robertson, Louise. "Optimising coagulation and ozone pre-treatments and comparing the efficacy of differently pre-treated grain distillery wastewaters in an upflow anaerobic sludge blanket (UASB) reactor". Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/86286.
Testo completoAbstract (sommario):
Thesis (MScFoodSc)--Stellenbosch University, 2014.ENGLISH ABSTRACT: Large volumes of high strength wastewater are generated annually by distilleries. Treatment of this wastewater is essential to increase its reuse potential. Anaerobic digestion (AD) has been widely applied as high strength wastewater treatment. Additionally, grain distillery wastewater (GDWW) is high in fats, oils and grease (FOG) which can cause problems during AD. Pre-treatment is therefore often required to make the AD process more efficient. The overall objective of this study was to investigate the operational efficiency of upflow anaerobic sludge blanket (UASB) reactors while treating GDWW as substrate. The first aim was to investigate the pre-treatment of the GDWW specifically for the removal of FOG by evaluating the effect of pH adaption, coagulant concentration and ozone (O3) dosages on the FOG reduction efficiency. Secondly, the effect of two different pre-treatments (only coagulant and coagulant and ozone) on the subsequent UASB treatment step was investigated. The pH of raw GDWW (pH 3.4) was adapted to three different pH values (5.0, 6.0, and 7.0) and the coagulant, aluminium chlorohydrate (ACH) (140 mg.L-1), was added. To make the process more economically viable, the lowering the coagulant concentration (to 100 mgACH.L-1) was also investigated. Optimal reductions for chemical oxygen demand (COD) (33.2% ± 4.93), total suspended solids (TSS) (91.9% ± 1.73) and FOG (84.1% ± 1.98) were, however, achieved at a higher coagulant concentration of 140 mgACH.L-1, and at a wastewater pH of 7.0. The effect of additional ozone treatment was also investigated. Maximum reductions for the ozone treatment were obtained at 100 mgO3.L-1 for COD (3.6% ± 4.08), and at 900 mgO3.L-1 for TSS (27.7% ± 5.58) and FOG (23.9% ± 1.83). The ozone treatment was most efficient for FOG reduction (in terms of mg FOG reduced per mg ozone) at 100 mgO3.L-1. An ozone dosage of 300 mgO3.L-1, was decided on based on economic feasibility, findings in literature on toxicity of ozone and the potential degradation of recalcitrant compounds at this dosage. The final pre-treatment thus included pH adaption to 7.0, coagulant dosage of 140 mgACH.L-1, and an ozone dosage of 300 mgO3.L-1. The second part of this study involved the operation of two 2 L laboratory scale UASB reactors for 277 days. The substrate of the first reactor contained GDWW that had only undergone coagulant pre-treatment (Rcontrol), while the substrate of the second UASB reactor consisted of GDWW that had undergone coagulant and ozone pre-treatment (Rozone). Both reactors treated the pre-treated GDWW successfully at ca. 9 kgCOD.m-3d-1. COD reductions of 96% for Rcontrol and 93% for Rozone, were achieved. FOG reductions (%) showed variations throughout the study and maximum reductions of 88% and 92% were achieved for Rcontrol and Rozone, respectively. The Rozone produced more biogas, but the methane content was similar for both reactors. The additional ozone pre-treatment did not show any added benefits to the reactor performance results. UASB granule washout in Rcontrol did, however, suggest possible toxicity of unsaturated fatty acids present in the non-ozonated substrate. The feasibility of FOG removal was shown as both reactors successfully treated pre-treated GDWW. Ozonation, after a coagulant dosage, which resulted in further reduction in the FOG content of the GDWW, is thus not essential to ensure the success of an anaerobic digestion step. Ozonation of the pre-treated GDWW could, however, be beneficial to gas production and the efficiency of a tertiary biological process.
AFRIKAANSE OPSOMMING: Groot volumes hoë-sterkte afloopwater word jaarliks deur distilleerderye opgelewer. Die behandeling van hierdie afloopwater is noodsaaklik om die hergebruiksmoontlikheid daarvan te verhoog. Die toepassing van anaërobiese vertering (AV) is wydverspreid in hoë-sterkte afloopwaterbehandeling. Graandistillerings-afloopwater (GDAW) is boonop hoog in vette, olies en ghries (VOG), wat probleme kan veroorsaak tydens AV. Voorbehandeling word dus dikwels verlang om die AV meer doeltreffend te maak. Die oorhoofse doelstelling van hierdie studie was om die doeltreffendheid van opvloei-anaërobieseslykkombers- (OAS-) reaktore wat GDAW as substraat behandel, te ondersoek. Die eerste mikpunt was om die voorbehandeling van die GDAW, te ondersoek vir die verwydering van VOG. Dit is uitgevoer deur die uitwerking van pH aanpassing, koagulantkonsentrasie en osoon(O3)dosis op VOG vermindering te evalueer. Tweedens is die uitwerking van twee verskillende voorbehandelings (slegs koagulant asook koagulant en osoonbehandeling) op die opvolgende OAS-behandelingsstap ondersoek. Die pH van rou GDAW (pH 3.4) is aangepas tot drie verskillende pH waardes (5.0, 6.0 en 7.0) en die koagulant, aluminium-chlorohidraat (ACH), is bygevoeg (140 mg.L-1). Om die proses meer ekonomies uitvoerbaar te maak is ‘n verlaagde koagulantkonsentrasie (verlaag tot 100 mgACH.L-1) ook ondersoek. Die optimale afnames vir chemiese suurstofvereiste (CSV) (33.2% ± 4.93), totale oplosbare vastestowwe (TOV) (91.9% ± 1.73) en VOG (84.1% ± 1.98) is egter bereik teen ‘n hoër koagulant konsentrasie van 140 mgACH.L-1, en teen ‘n afloopwater-pH van 7.0. Die uitwerking van ‘n bykomende osoonbehandeling is ook ondersoek. Die hoogste afnames tydens die osoonbehandeling is bereik teen 100 mgO3.L-1 vir CSV (3.6% ± 4.08), en teen 900 mgO3.L-1 vir TOV (27.7% ± 5.58) en VOG (23.9% ± 1.83). Die osoonbehandeling was mees doeltreffend vir VOG (in terme van mg VOG verwyder per mg osoon) teen 100 mgO3.L-1. Daar is besluit op ‘n van 300 mgO3.L-1, as gevolg van die ekonomiese uitvoerbaarheid, bevindinge in literatuur vir die toksisiteit van osoon, en die moontlike afbraak van moeilik-afbreekbare komponente teen hierdie dosis. Die finale voorbehandeling het dus bestaan uit ‘n aanpassing van die afloopwater-pH na 7.0, ‘n koagulantdosis van 140 mgACH.L-1, en ‘n osoondosis van 300 mgO3.L-1. Tydens die tweede gedeelte van hierdie studie is twee 2 L laboratoriumskaal OAS reaktore bedryf vir 277 dae. Die substraat van die eerste reaktor het GDAW bevat wat slegs ‘n koagulant-voorbehandeling ondergaan het (Rkontrole), terwyl die substraat van die tweede OAS-reaktor GDAW bevat het wat koagulant- en osoon-voorbehandeling ondergaan het (Rosoon). Beide reaktore het die voorbehandelde-GDAW suksesvol behandel teen ‘n organieseladingstempo van ca. 9 kgCSV.m-3d-1. Afnames in CSV van 96% vir Rkontrole en 93% vir Rosoon, is bereik. Tydens die studie is deurlopende wisseling in VOG verwydering (%) waargeneem, en die hoogste verwyderings wat bereik is, is onderskeidelik 88% en 92% vir Rkontrole en Rosoon. Die Rosoon het meer biogas geproduseer, maar die metaanpersentasie was soortgelyk vir beide reaktore. Die osoon-voorbehandeling het nie enige toegevoegde voordele getoon in die reaktorprestasie resultate nie. Die uitwas van die OAS-granules vir die Rkontrole het egter moontlike toksisiteit van onversadigdevetsure aangedui, wat moontlik teenwoordig kon wees in die nie-geösoneerde substraat. Die uitvoerbaarheid van VOG verwydering is getoon aangesien beide reaktore voorbehandelde GDAW suksesvol behandel het. Osonering, wat verdere afname in die VOG inhoud van GDAW teweeggebring het (na ‘n koagulant dosis), is dus nie noodsaaklik vir die suksesvolle verloop van ‘n anaërobiese-verteringsstap nie. Osonering van die voorbehandelde GDAW kan egter voordelig wees vir gasvorming, en kan ook verder die doeltreffendheid van ‘n tersiêre biologiese behandeling verhoog.
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Antovic, Aleksandra. "Determinations of the overall haemostasis potential and fibrin gel permeability : method development and application in research and in clinical materials /". Stockholm, 2004. http://diss.kib.ki.se/2004/91-7349-932-3/.
Testo completo
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Gewehr, André Granzotto. "Tratamento por coagulação-floculação de lixiviado bruto de aterro sanitário com e sem pré-tratamento biológico em reator sequencial em batelada". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/62110.
Testo completoAbstract (sommario):
A forma de tratamento e destinação final ainda mundialmente preponderante para os resíduos sólidos urbanos é o aterro sanitário, método que gera, além de uma massa sólida residual, parcialmente estabilizada, subprodutos finais líquidos e gasosos. O efluente líquido, conhecido como lixiviado, necessita tratamento específico, devido a sua elevada nocividade ao meio ambiente, em função, principalmente, de suas elevadas concentrações de nitrogênio amoniacal e de matéria orgânica, em elevado percentual, recalcitrante. O presente trabalho avaliou em escala de bancada o tratamento, via processo físico-químico, através de coagulação-floculação, de lixiviado bruto proveniente de aterro sanitário Central de Resíduos do Recreio (operado pela Companhia Riograndense de Valorização de Resíduos), desprovido de qualquer tratamento prévio, e de lixiviado pré-tratado biologicamente em reatores sequenciais em batelada (RSB). Para o processo de coagulação-floculação foram testados os coagulantes policloreto de alumínio (PAC), cloreto férrico, sulfato férrico e tanino. Sucessivas etapas foram planejadas para a determinação de dosagem e ajuste de pH ótimos, para cada coagulante empregado, e para a verificação da influência de tempos e gradientes de misturas, bem como foi testada a aplicação de polímeros auxiliares de floculação. As variáveis resposta utilizadas para o monitoramento e a avaliação de eficiências foram a cor verdadeira, turbidez (com e sem prévia filtração), DQO, volume de lodo gerado e pH. O uso de reator sequencial em batelada objetivou nitrificação/desnitrificação convencional das elevadas concentrações de nitrogênio amoniacal e eventual oxidação de matéria carbonácea. Verificou-se que os diferentes tempos e gradientes de mistura testados, assim como a utilização de polímeros auxiliares, não produziram impactos nos resultados. Os coagulantes inorgânicos apresentaram elevadas eficiências de remoção, com destaque para o cloreto férrico, o qual na dosagem de 1102 mgFe+3/L e ajuste inicial de pH em 6,2 removeu 98% da cor verdadeira e da turbidez filtrada, 63% da DQO, 40% da DBO5, e 88% de turbidez não filtrada do lixiviado bruto. Apesar da recalcitrância de considerável fração da matéria orgânica do lixiviado, o RSB2 removeu 40% da DQO e 60% da DBO5 originais. A coagulação-floculação do efluente do RSB2 necessitou inferiores dosagens dos coagulantes em relação ao processo com lixiviado bruto. O cloreto férrico, em dosagem ótima de 826 mgFe+3/L e ajuste de pH em 6,3, removeu 95% da cor, 77% da DQO, 82% da DBO5, 94% da turbidez filtrada e 92% da turbidez não filtrada. Concluiu-se por elevada viabilidade técnica do processo de coagulação-floculação para o lixiviado com e sem pré-tratamento, a partir da otimização das condições de contorno do processo. O pré-tratamento em RSB, quando utilizado controle de pH, demonstrou grande potencial para nitrificação/desnitrificação e oxidação de significante parcela da matéria carbonácea do lixiviado bruto.The form of treatment and disposal still prevalent worldwide for solid waste is the landfill, a method that generates, in addition to a solid mass residual partially stabilized, liquid and gas end products. The effluent liquid, known as leachate, requires specific treatment, due to its high harmfulness to the environment, due mainly to its high concentrations of ammonia nitrogen and organic matter in high percentage, recalcitrant. This study evaluated the treatment on bench scale, via physico-chemical process, by coagulation-flocculation, of raw leachate from Central de Resíduos do Recreio landfill (operated by Companhia Riograndense de Valorização de Resíduos), devoid of any previous treatment, and biologically pretreated leachate reactors in sequential batch reactors (SBR). For the process of flocculation-coagulation were tested polyaluminum chloride (PAC), ferric chloride, ferric sulfate and tannin. Successive stages were designed for determining dosage and optimum pH adjustment for each coagulant employed and for verifying the influence of times and gradients mixtures, as well as tested in the application of polymers flocculation auxiliaries. The answers used for parametric monitoring and evaluation of efficiencies were the true color, turbidity (with and without prior filtration), COD, sludge volume and pH. The use of sequential batch reactor aimed conventional nitrification/denitrification of the high concentrations of ammonia nitrogen and eventual oxidation of carbonaceous matter. It was found that the different gradients and mixing times tested, as well as the use of auxiliary polymers, did not produce impact on the results. The inorganic coagulants showed high removal efficiencies, especially ferric chloride, which at a dose of 1102 mgFe+3/L and initial pH adjusted to 6.2, removed 98% of the true color and filtered turbidity, 63% of COD, 40% of BOD5 and 88% of unfiltered turbidity. Despite the considerable fraction of the recalcitrance of organic matter in the leachate, the SBR2 removed 40% of COD and 60% of BOD5 of the original. The coagulation-flocculation of the effluent from SBR2 required lower dosages of coagulants in relation to the similar process with raw leachate. Ferric chloride in optimum dosage of 826 mgFe+3/L and adjusting pH to 6.3, removed 95% of color, 77% of COD, 82% of BOD5, 94% of the filtered turbidity and 92% of unfiltered turbidity. It was concluded by high technical feasibility of the process of flocculation-coagulation for the leachate with and without pre-treatment, based on the optimization of the boundary conditions of the process. The pre-treatment with SBR, when pH control, demonstrated high potential for nitrification/denitrification and oxidation of a significant portion of the carbonaceous of the raw leachate.
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Karlsson, Jessica. "Sample cradle prevents pre-analytic error on platelet counts but is not essential for hemoglobin measurement and prothrombin time". Thesis, Uppsala universitet, Institutionen för medicinsk biokemi och mikrobiologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-182146.
Testo completoAbstract (sommario):
Introduction: It is recommended to place all the vacuum tubes directly on a sample cradle after vein puncture to prevent analytic error. This recommendation is not always easy to follow because the samples are taken by different professionals under different situations. The three most common analyses, platelets count, haemoglobin and prothrombin time were tested. Therefore, it was interesting to compare results from the three most common analyses with or without sample cradle, to evaluate the influence of this step on the result. Methods: Three analyses were preformed, using blood from 50 different persons. Each person gave two vacuum tubes, each contained 4.5mL of venous blood for the study. Tubes containing EDTA were used for platelet counts and measurement of haemoglobin and tubes containing citrate were used for prothrombin time-analysis. One of the tubes was placed, as recommended, directly on the sample cradle while the other tube was placed flat on a bench for 10 minutes before it was placed on the sample cradle. Results: There was a clear difference in platelet counts with and without immediate cradling but only minor difference between the results for haemoglobin and International Normalized Ratio. Conclusion: Some analyses seem to be more sensitive for variation in cradling than others. For platelet count it was important to immediately rock the tubes but for determination of prothrombine time and hemoglobin it had a small impact. The small impact on the results is probably due to the efficiency of the anticoagulant in the vacuum tubes.
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Daniel, Steven A. School of Medicine UNSW. "Pre-coagulation of solid organs". 2007. http://handle.unsw.edu.au/1959.4/40723.
Testo completoAbstract (sommario):
Coagulation has and continues to be one of the most important elements in medicine. Issues from a lack of hemostasis range from poorer clinical outcomes to sudden death. The evolution of treatments for hemostasis have evolved from the use of Tamponade with direct pressure and bandages, the use of materials such as cobwebs and dust, the use of heat with hot oil or heated irons, to the use of suture, glues, plasmas, staplers, and electricity. This evolution has continued to bring about the prophylactic use of technology in an effort to prevent blood loss. This change from reactive treatments to proactive continue to be on a localized or superficial basis. One of the largest opportunities to proactively reduce blood loss in surgical patients is during the resection of solid organs such as the liver, kidney, and spleen. Few options have existed to help improve hemostasis short of the complete occlusion of blood supplying the tissue such as in the Pringle Maneuver. Recent studies have begun to show that practices such as this may have a significant detrimental effect on morbidity. It has been found that by applying radio frequency electrical energy in a particular way that large amounts of tissue can be pre-coagulated prior to resection. A series of animal and human clinical work has been completed to help evolve and confirm the method and the device that was created and refined during this effort. During the course of this work fifty-three patients were treated at four institutions on three continents. Average blood loss for liver resections performed with this pre-coagulation technique using the developed device in a multicenter control trail was 3.35 ml/cm2 as compared to 6.09 ml/cm2 (p < 0.05) for resections performed using standard surgical techniques alone. Additionally, the transection time necessary was also reduced from mean value of 27 minutes (2 -- 219 minutes) to 35 minutes (5 -- 65 minutes). Patients treated included those suffering from liver cirrhosis, fatty liver disease, and post chemotherapy fibrosis. From this work the use of pre-coagulation with methods and device developed was shown to be safe and effective for reducing the amount of blood loss and transection time during liver resections.
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Shanwe-Chen e 陳聖偉. "The Effect of Pre-oxidation in Coagulation and Precipitation". Thesis, 2010. http://ndltd.ncl.edu.tw/handle/50452169223038560961.
Testo completoAbstract (sommario):
碩士國立成功大學
環境工程學系碩博士班
98
English Abstract Eutrophication in reservoir leads to algal blooms during spring and summer days. After death, algae release organic compounds and reducing materials such as iron and manganese. These chemical in the reservoir may cause turbidity, odor, and color increasing, resulting in consuming more coagulant and pre-oxidants 、the higher turbidity of outflow of sedimentation tank and increasing frequency of filter backwash. This study take Baoshan water treatment factory, which converge Baoshan Reservoir and Baoshan second Reservoir water as the main source of raw water, as research object to discuss the effect of raw water treatment efficiency after different dosage and different types of pre-oxidant、coagulant treatment by laboratory test and model test. The results showed that using chlorine as pre-oxidants can reduce the turbidity without coagulant treatment. However, manganese dioxide produced by using potassium permanganate as pre-oxidants would increase water turbidity. Taking alum as a coagulant, it has positive effects whether chlorine or potassium permanganate as pre-oxidants in the removal of turbidity and particles. However, taking ferric chloride to replace the alum as coagulant, chlorine as pre-oxidant can easily make flocs formation decrease, resulting in more residual particles in the outflow of sedimentation tank than without pre-oxidants treatment. Compare the effect of different coagulants, we can see that using ferric chloride as coagulant is better than alum in the removal of turbidity and particles. In the removal of organic compound-- NPDOC, it has no significant difference with low-dosage pre-oxidants treatment. The efficiency of Permanganate - ferric chloride process is higher than no pre-oxidation treatment, or chlorine- ferric chloride process for the removal of NPDOC. However, either potassium permanganate or chlorine as pre-oxidants in high-dose treatment would lead to NPDOC significantly increased. Taking disinfection byproducts formation potential : THMFP7days, as an example, the main sources of disinfection by-product is soluble organic compounds.Particulate and organic compounds seldom cause disinfection by-product formation. Process of using ferric chloride as coagulant and potassium permanganate as pre-oxidant generated good removal efficiency than alum in the formation potential of disinfection by-products
Libri sul tema "Pre-coagulation"
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Shammala, Wesam Abu. Human plasma Kallikrein and pre-Kallikrein: Immunochemical adsorption studies using selected non-biological surfaces. Dublin: University College Dublin, 1999.
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Carter, R., e C. W. Imrie. Hepatobiliary surgery. Oxford University Press, 2011. http://dx.doi.org/10.1093/med/9780198510567.003.0008.
Testo completoAbstract (sommario):
Introduction 306Investigational procedures 308Pancreatic mobilisation 310Management of tumours 312Management of pancreatic necrosis 316Management of pseudocyst 318Management of chronic pancreatitis 320Common pancreatic complications 322As the morbidity and mortality associated with pancreatic surgery are amongst the highest in surgical practice, management of patients should take place within the context of multi-disciplinary team and they should be in optimal condition pre-operatively. They may be suffering from exocrine failure, altered glucose tolerance, or altered coagulation due to post-hepatic biliary obstruction. All these issues should be addressed. Most surgical procedures will require blood to be cross-matched....
Capitoli di libri sul tema "Pre-coagulation"
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Dondelinger, R. F. "Use of Anticoagulants and Clotting Agents — Procedures in Patients with Pre-existing Coagulation Disorders". In Interventional Radiology, 111–21. Berlin, Heidelberg: Springer Berlin Heidelberg, 1993. http://dx.doi.org/10.1007/978-3-662-01654-1_11.
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Daud, Nurull Muna, Siti Rozaimah Sheikh Abdullah e Hassimi Hasan. "Optimization of Coagulation Process for the Pre-Treatment of Biodiesel Wastewater Using Response Surface Methodology (RSM)". In From Sources to Solution, 433–37. Singapore: Springer Singapore, 2013. http://dx.doi.org/10.1007/978-981-4560-70-2_78.
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Robinson, Chapman. "Pregnancy and breathlessness". In Oxford Handbook of Respiratory Medicine, a cura di Stephen J. Chapman, Grace V. Robinson, Rahul Shrimanker, Chris D. Turnbull e John M. Wrightson, 69–72. Oxford University Press, 2021. http://dx.doi.org/10.1093/med/9780198837114.003.0010.
Testo completoAbstract (sommario):
Elevated serum progesterone levels stimulate respiratory drive and lead to an increased tidal volume and raised minute ventilation, with only a modest increase in O2 consumption. Any cause of maternal hypercapnia leads quickly to foetal respiratory acidosis. Elevation of the diaphragm occurs due to the enlarging uterus, leading to a reduced functional residual capacity (FRC). Raised levels of coagulation factors and impaired fibrinolysis, combined with venous stasis, result in a significantly increased risk of venous thromboembolism (VTE). Upper airway oedema, particularly in the setting of pre-eclampsia, may predispose to upper airway obstruction during sleep, but rarely frank OSA. OSA tends to occur in obese women and may be associated with impaired foetal growth and pre-eclampsia. Snoring in pregnancy is a poor predictor of OSA.
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Arora, Lovkesh, Sung Kim e Surangama Sharma. "Update on Blood Management in Liver Transplant". In Anesthesiology: A Problem-Based Learning Approach, a cura di Tracey Straker e Shobana Rajan, 181–88. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780190850692.003.0020.
Testo completoAbstract (sommario):
Hemostasis in patients presenting for liver transplantation is characterized by a reduction in both pro- and anticoagulant factors. Blood loss is due to multiple factors but usually a consequence of pre-existing abnormalities of the hemostatic system, portal hypertension with multiple collateral vessels, portal vein thrombosis, previous abdominal surgery, splenomegaly, and poor functional recovery of the new liver. The intrinsic coagulopathic features of end-stage cirrhosis along with surgical technical difficulties make transfusion-free liver transplantation a major challenge, and, despite the improvements in understanding of intraoperative coagulation profiles and strategies to control blood loss, the requirements for blood or blood products remains high. The impact of blood transfusion has been shown to be significant and independent of other well-known predictors of post-transplant outcome.
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Baldwin, Andrew, Nina Hjelde, Charlotte Goumalatsou e Gil Myers. "Obstetrics". In Oxford Handbook of Clinical Specialties, 1–97. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780198719021.003.0001.
Testo completoAbstract (sommario):
This chapter explores obstetrics, including obstetric histories, abdominal examination, physiological changes in pregnancy, pre-pregnancy counselling, the placenta, plasma chemistry in pregnancy, antenatal care, structural abnormalities and ultrasound, screening and diagnosis of aneuploidy, minor symptoms of pregnancy, hyperemesis gravidarum, sickle cell disease in pregnancy, cardiac disease in pregnancy, drugs used in psychiatry and epilepsy, anaemia, HIV in pregnancy and labour, diabetes mellitus in pregnancy, thyroid disease in pregnancy, jaundice in pregnancy, malaria, renal disease in pregnancy, epilepsy, respiratory disease in pregnancy, connective tissue diseases in pregnancy, hypertension in pregnancy, thromboprophylaxis, thrombophilia in pregnancy, venous thromboembolism, infection, group B streptococcus (GBS), abdominal pain in pregnancy, sepsis in pregnancy and the puerperium, fetal monitoring in labour, pre-eclampsia, prematurity, small for gestational age (SGA), postmaturity (prolonged pregnancy), maternal collapse, antepartum haemorrhage, prelabour rupture of membranes at term, normal labour, induction of labour, management of delay in labour, home birth, pain relief in labour, multiple pregnancy, breech presentation and other malpresentations/malpositions, cord prolapse, shoulder dystocia, meconium-stained liquor, operative vaginal delivery, caesarean section (CS), uterine rupture, mendelson’s syndrome, stillbirth (intrauterine fetal death, IUD), postpartum haemorrhage (PPH), retained placenta, uterine inversion, placenta praevia, accreta and increta, DIC and coagulation defects, amniotic fluid embolism, birth injuries, episiotomy and tears, the puerperium, maternal and perinatal mortality.
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Redman, C. W. G. "Hypertension in pregnancy". In Oxford Textbook of Medicine, 2093–102. Oxford University Press, 2010. http://dx.doi.org/10.1093/med/9780199204854.003.1404.
Testo completoAbstract (sommario):
In normal pregnancy the arterial pressure falls in the second half of the first trimester: systolic pressure then remains unchanged throughout pregnancy, with diastolic pressure tending to rise gradually towards its prepregnancy level in the later weeks. Definitions, epidemiology and clinical features—(1) Pregnancy-induced hypertension (PIH), transient hypertension of pregnancy, or gestational hypertension describe new hypertension, defined as blood pressure equal to or in excess of 140/90 mmHg, which without proteinuria affects up to 10% of women after mid term (20 weeks) and resolves after delivery. (2) Pre-eclampsia, which affects 3 to 5% of pregnancies, is defined by the presence of PIH and pregnancy-induced proteinuria arising after 20 weeks gestation that both improve after delivery. Other features include (a) renal insufficiency; (b) hepatocellular dysfunction and/or severe epigastric/right upper quadrant pain; (c) neurological problems—convulsions (eclampsia), severe headaches, persistent scotomata; (d) haematological disturbances—thrombocytopenia, disseminated intravascular coagulation, haemolysis; (e) fetal growth restriction....
Atti di convegni sul tema "Pre-coagulation"
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Li, Honglan, Kefeng Zhang e Yonglei Wang. "Influence of Pre-Ozonation on Coagulation of Micro-Polluted Surface Water from Yellow River". In 2008 2nd International Conference on Bioinformatics and Biomedical Engineering. IEEE, 2008. http://dx.doi.org/10.1109/icbbe.2008.1024.
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Liu, Juan-fang, Xu-dong Jiang e Xue-dong Zhai. "Enhanced coagulation of low turbidity and low temperature surface water by potassium permanganate composite pre-oxidation". In 2011 International Conference on Electric Technology and Civil Engineering (ICETCE). IEEE, 2011. http://dx.doi.org/10.1109/icetce.2011.5775927.
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Iwasaki, Ryosuke, Ryo Takagi, Shin Yoshizawa e Shin-ichiro Umemura. "Notice of Removal: Prediction of thermal coagulation by short-pulse pre-exposure for cavitation-enhanced ultrasonic heating". In 2017 IEEE International Ultrasonics Symposium (IUS). IEEE, 2017. http://dx.doi.org/10.1109/ultsym.2017.8092354.
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Lee, L., A. Guardia, S. Sereshki, G. Chithyoka, D. Mpando, T. Phiri, J. Kachingwe et al. "EP316 Cervical pre-cancer screen and treat program using visual inspection by acetic acid and thermo-coagulation in Malawi". In ESGO Annual Meeting Abstracts. BMJ Publishing Group Ltd, 2019. http://dx.doi.org/10.1136/ijgc-2019-esgo.377.
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Cooper, P. C., D. R. Triger, H. Kennedy, R. G. Malia e F. E. Preston. "FIBRINOLYSIS AND HAEMOSTASIS DURING ASCITES RECIRCULATION". In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643061.
Testo completoAbstract (sommario):
The use of ascites recirculation in liver disease removes litres of incapacitating fluid and the patient is reinfused with the concentrated ascites, a rich source of albumin. Ascites is thought to contain plasminogen activator (PA) which may further affect deranged haemostasis in these patients. We have examined the effect that ascites recirculation has on levels of tPA, fibrinogen, FDP and platelet count on samples taken pre and approximately 4 hours into ascites recirculation. Using plasminogen rich fibrin plates we were able to demonstrate PA in unfractioned ascitic fluid (N=10, mean diameter lysis=10.2mm); this activity was quenched by addition of antibody to tPA (mean diameter lysis=0.2mm). Despite demonstrating tPA in unfractioned ascitic fluid, we were unable to demonstrate an increase in plasma tPA, mid recirculation, using a sensitive chromogenic assay (pre, geometric mean tPA = 0.061Iu/ml; mid, geometric mean tPA = 0.024Iu/ml). In addition we have also measured the effect that an intra-abdominal injection of the glucocorticoid, dexamethosone (dex), 24 hours prior to recirculation, has on PA content of the ascites, as well as the effect on coagulation screening tests. Fibrin plate lysis showed only a small, though significant reduction in mean lysis diameter in 9 of 10 patients receiving dex, (mean 11.6 to 10.2mm). Results of the coagulation tests showed marked changes during recirculation which were similar in both groups.In conclusion, we have demonstrated free tPA in unfractionated ascites fluid of patients with liver disease, and shown a small reduction in tPA level 24 hours post injection of dex in ascites. Dexamethosone did not influence the changes in coagulation profile post recirculation. We suggest that the changes in coagulation are not due to primary fibrinolysis, but may be due to either dilution effect or DIG.
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Ruiz, M. A., I. Marugán, A. Estellés, F. Espafia, J. Aznar e J. García-Conde. "THE INFLUENCE OF CHEMOTHERAPY ON THE PLASMATIC COAGULATION AND FIBRINOLYTIC SYSTEM IN LUNG CANCER PATIENTS". In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643187.
Testo completoAbstract (sommario):
Following the administration of cytostatic drugs, an increase in thromboembolic phenomena has been described in cancer patients. Such hemostatic alterations may be related to degree of hipercoa-gulability observed following chemotherapy, in comparison to previous levels. In terms of the fibrinolytic system, however, no - clearly defined alterations have been detected. We studied the - changes in plasmatic coagulation and fibrinolysis in 40 patients with non-operable stage III and IV lung cancer (30 epidermoid - ad 10 microcytic neoplasms) following cytostatic chemotherapy. Two studies were done on each patient, i.e., one at the time of diagnosis, -and the other 48 hours after completing the first chemotherapeutic cycle. The results show significant (p 0,05) post-chemotherapy increases in fibrinopeptide A (FPA) levels (pre: 2.95 ± 3.98, post: 8.15 ± 9.40 ng/ml), as well as a decrease in fibrinolytic activity reflected by a drop (p 0.01) in functional tissue plasminogen activator (t-PA) (pre: 1.53 ± 1.66, post: 0.91 ± 0.95 ng/ml). Morever, a tendency towards reduced euglobulinic precipitate lysis on fibrin agar was observed (pre: 122.8 ± 85.7, post: 105 ± 71.5%). The other parameters evaluated, i.e., antithrombin III, plasminogen immunologic t-PA and functional PA inhibitor - (PAI) showed no significant changes.We have also studied the potential accumulative effect of three chemotherapy courses and the results were compared to the situation at the time of diagnosis. A significant increase p 0.01 in functional PAI has been observed (pre: 1.85 ± 2.38, post: 5.41 ± 3.74 U/ml). The possible participation of tumor mass in the elevation of these parameter was considered: but no relation betwen tumor mass and increase PAI have been detected.Chemotherapy is apparently capable of conditioning a decrease in fibrinolytic activity in these cancer patients, this could be related to the enhanced tendency of these patients to developing - thromboembolic phenomena following cytostatic chemotherapy.
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Teitel, J. M., M. B. Garvey e J. J. Freedman. "THE ENDOTHELIAL CELL AS THE SII$ OF THE FACTOR VIII BYPASSING ACTIVITY OF PROTHROMBIN COMPLEX CONCENTRATE (PCC)". In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1644731.
Testo completoAbstract (sommario):
PCC is used empirically for its factor VIII (FVIII) bypassing activity in hemophiliacs with inhibitors to FVIII. The effect of of PCC on plasma coagulation tests is variable and is not predictive of clinical response. We are testing the hypothesis that bypass activity is expressed locally at the vessel wall, which functions as a procoagulant surface at times of hemostatic stress. Monolayer cultures of umbilical vein endothelial cells (EC) were incubated for 1 hour with commerical PCC (1 u/ml), and then extensively washed to remove fluid phase PCC components. Ellagic acid-activated PTT determinations were then done over the treated monolayers using plasma deficient in FVIII (<1 u/ml). PTTs over EC pre-treated with PCC were shorter than PTTs with control EC or EC pre-treated with commercial FVIII concentrate (control 101 s, PCC treated 57.7 s, FVIII treated 84 s, means of n=3). Similar results were obtained using non-activated PTTs and with adult saphenous vein EC. The bypass effect of PCC was dose-related:non-activated PTTs were 172 s (control),134 s (PCC 0.1 u/ml),and 107 s (PCC 1 u/ml). Pre-treatment of EC with cycloheximide shortened the PTT of FVIII deficient plasma, presumably due to impaired expression of endogenous anticoagulant activity.Subsequent incubation of cycloheximide pre-treated EC with PCC still provided FVIII bypass activity. In contrast, FVIII consistently failed to shorten the PTT using FVIII deficient plasma added to cycloheximide pre-treated EC. Thfe ability of PCC to bypass the FVIII defect was not impaired using paraformaldehyde 1fixed in place of live EC, but was reduced or abolished if the ECwere incubated with PCC at 4° instead of 37°.The putative FVIII bypassing component present in PCC may therefore express its activity only upon interacting with EC at sites of vascular interruption. Further studies using purified reagents will be necessary to identify the responsible substance(s). These observations may help explain the discrepancy between the clinical. efficacy of PCC and its inconsistent effect on plasma coagulation tests.
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Miekka, Shirley I. "USE OF ALBUMIN AND TWEEN AS STABILIZERS TO PREVENT ACTIVITY LOSS DURING CLOTTING ASSAYS OF COAGULATION FACTOR IX AND X CONCENTRATES". In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1644065.
Testo completoAbstract (sommario):
Assays for clotting activities of Vitamin K-dependent coagulation factors in Factor IX complex concentrates are IcnovTn to give variable results depending on the composition of the sample diluent. Higher potency values are obtained when deficient plasma is used for sample pre-dilution compared with dilution in buffer. This discrepancy is more pronounced in assays of higher purity Factor IX (FIX) or Factor X (FX) concentrates. We have found that addition of a mixture of bovine albumin (0.1% w/v) and Tween 20 (0.01% v/v) (BAT) to the dilution buffer can eliminate the discrepancy, giving clotting times and plot slopes equal to chose obtained upon dilution in deficient plasma. Less protection was obtained with either albumin or Tween added separately. Polyethylene glycol 8000 (0.1% w/v), commonly used to stabilize thrombin solutions, gave variable results. BAT had no effect on clotting times of whole plasma or of FIX or FX samples pre-diluted in deficient plasma. Neither deficient plasma nor BAT had any effect when added after sample dilutions were prepared: activity of a FIX concentrate was 137 U/ml when pre-diluted in Factor IX-deficient plasma and 1312 U/ml diluted in BAT, compared with 49 U/ml diluted in buffer alcne; addition of deficient plasma or BAT to the dilutions of sample in buffer gave activities of only 36 a).id 34 U/ml, respectively. Similar results were obtained with FX samples. Furthermore, when a solution of FX (pre-diluted to 1 U/ml in buffer without stabilizer) was merely transferred from one test tube to another without further dilution, clotting times increased progressively and activity decreased by 85% after 8 transfers. By contrast, an identical sample diluted to 1 U/ml with BAT remained essentially unchanged after 8 serial transfers. These results indicate that Vitamin K-dependent coagulation factors are very susceptible to surface adsorption or inactivation after dilution of concentrates, and that either BAT or deficient plasma will prevent this loss. The use of albumin and Tween as stabilizers provides a simpler, .less expensive alternative to prevent nonspecific surface adsorption and achieve more accurate measurement of clotting activities.
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Yuan, Y., N. Vora, C. Sun, D. Li, J. Mortimer, T.-h. Luu, G. Somlo et al. "Abstract P6-07-13: Association of pre-chemotherapy peripheral blood pro-inflammatory (IL-6, CRP) and coagulation (D-dimer) markers with chemotherapy toxicity in women with breast cancer". In Abstracts: 2016 San Antonio Breast Cancer Symposium; December 6-10, 2016; San Antonio, Texas. American Association for Cancer Research, 2017. http://dx.doi.org/10.1158/1538-7445.sabcs16-p6-07-13.
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Wilson, J., P. J. Grant, M. Boothby, J. A. Davis e C. R. M. Prentice. "ENDOGENOUS VASOPRESSIN RELEASE CONTRIBUTES TO THE THROMBOTIC RISK OF HIP SURGERY". In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643695.
Testo completoAbstract (sommario):
Vasopressin (aVP) infusions in man that simulate physiological concentrations in plasma produce increases inboth factor VIII and plasminogen activator activity (PAA) and we have found evidence that aVP release contributes to the activation of coagulation during abdominal surgery. The aimof this study was to investigate whether aVP has a similar role in theregulation of haemostasis during hipsurgery. Venous blood samples were taken for FVIII:C, FVIII RiCof, vWF:Ag,fibrinopeptide A (FPA), ECLT, platelet aggregation in whole blood andaVPfrom separate venepuncture sites in 7 patients undergoing elective hip surgery. Samples were taken pre-operatively, post induction of anaesthesia, at skin incision, during divisionof the femoral neck, reaming of the acetabulum, cementing of the prosthesisand on thefirst post-operative day. FVIII:C increased during the operation from a geometric mean of 70%pre-operativelyto 109% (p < 0.05) post-operativgly.vWF:Ag and FVIII RiCof rose in a similar manner. PAA (106 /ECLT2) rose significantly from 12 units pre-operatively to a peak value of 167 units(p< 0.001) at prosthesis cementing,andpost-operatively fell to subnoral levels. FPA concentrations followed a similar pattern rising from13 pmol/ml to 58 psmol/ml (p < 0.02)atprosthesis cementing, and falling to9pmol/ml post-operatively. PlasmaaVP rosefrom 0.5pg/ml pre-operatively to 40pg/ml (p < 0.01) at division of the femoral neck, and returned to0.5 pg/ml post-operatively. There were no changes in platelet aggregation in whole blood using a single doseof 1.5 μM ADP. These results are similarto those we have observed duringabdominal surgery. They confirm thaduring surgery, thrombin generation occurs with increased PAA,both of which are preceded by a risein aVP. This isconsistent with the hypothesisthat aVP is an important mediatorof changes in haemostatic function occurringduring surgery, and we are now investigating the relationship between intra-operative changesin haemostaticfunctionand risk of post-operative DVT.