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Letteratura scientifica selezionata sul tema "Ovum Physiology"

Autore: Grafiati

Pubblicato: 4 giugno 2021

Ultima modifica: 27 gennaio 2023

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Articoli di riviste sul tema "Ovum Physiology"

Seneda, M. M., F. Morotti, A. F. Zangirolamo, N. C. da Silva, T. K. Sanches, W. Blaschi e T. R. R. Barreiros. "Antral follicle population in prepubertal and pubertal heifers". Reproduction, Fertility and Development 31, n. 1 (2019): 10. http://dx.doi.org/10.1071/rd18344.

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The antral follicle count (AFC) is an important tool in the selection of bovine females destined for biotechnology. However, little is known about AFC in prepubertal and pubertal heifers. Some challenges inherent to the physiology of young females must be considered to achieve efficient rates with different procedures, such as ovum pick-up and IVF. This paper covers some important topics about ovarian physiology related to the population of antral follicles and reproductive efficiency in young female cattle.

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Erickson, Gregory. "An Analysis of Follicle Development and Ovum Maturation". Seminars in Reproductive Medicine 4, n. 03 (agosto 1986): 233–54. http://dx.doi.org/10.1055/s-2007-1022504.

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Mishra, Sanjay, Amit Kumar Mani Tiwari, Ram B. Singh e Abbas A. Mahdi. "Sperm DNA Links from Sperm to Ovum to Implant Genetic Changeability: an Overview". SOJ Gynecology , Obstetrics & Women's Health 4, n. 1 (10 aprile 2018): 1–10. http://dx.doi.org/10.15226/2381-2915/4/1/00132.

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Sperm DNA disintegration is known to cooperate male fertility. The data bring about that sperm DNA cleavage can be competently treated with orally administered antioxidant during a relatively short moment period. It is an accepting thought that the two types of DNA become visible to be distinctive and autonomously packaged molecules; though, investigation has established the symbiotic nature of these structures in contributing to male infertility. Data should continue to be gathered to ascertain strong correlation between conventional semen examination parameters and sperm DNA integrity; this information remains contentious and inadequate in clinical practice until certain novel techniques for the diagnosis and treatment of sperm DNA can be established. Rather more modern technology should be employed to associate such information into practical clinical awareness. This overview compiles certain specific reports pertaining to studies on sperm DNA physiology, biochemistry and molecular biology to provide further new insights into establishing hypothesis that sperm DNA integrity is both enormously fragile and remarkably significant for male fertility. Keywords: Apoptosis; Male infertility; Sperm DNA

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Humblot, Patrice, Daniel Le Bourhis, Sebastien Fritz, Jean Jacques Colleau, Cyril Gonzalez, Catherine Guyader Joly, Alain Malafosse et al. "Reproductive Technologies and Genomic Selection in Cattle". Veterinary Medicine International 2010 (2010): 1–8. http://dx.doi.org/10.4061/2010/192787.

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The recent development of genomic selection induces dramatic changes in the way genetic selection schemes are to be conducted. This review describes the new context and corresponding needs for genomic based selection schemes and how reproductive technologies can be used to meet those needs. Information brought by reproductive physiology will provide new markers and new improved phenotypes that will increase the efficiency of selection schemes for reproductive traits. In this context, the value of the reproductive techniques including assisted embryo based reproductive technologies (Multiple Ovaluation Embryo Transfer and Ovum pick up associated toin vitroFertilization) is also revisited. The interest of embryo typing is discussed. The recent results obtained with this emerging technology which are compatible with the use of the last generation of chips for genotype analysis may lead to very promising applications for the breeding industry. The combined use of several embryo based reproductive technologies will probably be more important in the near future to satisfy the needs of genomic selection for increasing the number of candidates and to preserve at the same time genetic variability.

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Podolsky, Robert D. "Fertilization ecology of egg coats: physicalversuschemical contributions to fertilization success of free-spawned eggs". Journal of Experimental Biology 205, n. 11 (1 giugno 2002): 1657–68. http://dx.doi.org/10.1242/jeb.205.11.1657.

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SUMMARYFree-spawned eggs are typically enclosed within accessory structures that are shed early in development. Most research on the role of these structures in fertilization has focused on chemical constituents and their influence on sperm—egg interaction. Here I test an alternative hypothesis that accessory structures play an important physical role in fertilization by increasing the size and buoyancy of the egg, making it a better target for sperm. In the sand dollar Dendraster excentricus, the jelly coat increases egg target size sixfold. At nonsaturating sperm concentrations,fertilization declined consistently following jelly coat removal by two independent methods. Regression analysis using a standard fertilization kinetics model found that 54-73% of this decline on average was predicted by changes in the rate of sperm—egg collision, resulting from changes in egg target size and density. Sperm swimming speed, a key parameter in the model, did not vary as a function of sperm concentration or exposure to egg-water. The organic cost of jelly is a fraction of that of the ovum,providing an efficient means of extending target size beyond the ovum size that is optimal for larval or juvenile development. These results support the hypothesis that physical attributes of jelly coats can account for a significant portion of their contribution to fertilization, and may help to explain why coats and other accessory structures are often substantially larger than expected from the nature of chemical interactions between egg and sperm.

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Azumendi, Guillermo, Kazuo Maeda, Ritsuko K. Pooh e Iva Lausin. "Advances in Visualization of the Early Human Development". Donald School Journal of Ultrasound in Obstetrics and Gynecology 3, n. 3 (2009): 25–38. http://dx.doi.org/10.5005/jp-journals-10009-1018.

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Abstract The anatomy and physiology of placental and embryonic development is a field where medicine exerts its impact on early pregnancy and opens fascinating aspects of embryonic differentiation. The introduction of high frequency transvaginal transducers as well as three and four dimensional sonography has resulted in remarkable progress in ultrasonic visualization of early embryos and fetuses. Ultrasound has been widely used in the field of early human development due to its safety, diagnostic accuracy and convenience. Normal fetal anatomy and development have been widely investigated using two-dimensional ultrasound and most of the knowledge regarding early human development were established through understanding of sectional images of fetal body and organs obtained by two-dimensional ultrasound. Usage of new techniques has produced more objective and accurate information of embryonal and early fetal development. For the first time parallel analyses of structural and functional parameters in the first 12 weeks of gestation become possible. This article deals with establishment of human life from ovum and sperm, though fertilization, detailed histological development and the establishment of the placenta, and early human development visualized by 2- and 3-dimensional ultrasonography.

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Csöbönyeiová, M., I. Varga, L. Lapides, L. Pavlíková, C. Feitscherová e M. Klein. "From a Passive Conduit to Highly Dynamic Organ. What are the Roles of Uterine Tube Epithelium in Reproduction?" Physiological Research 71, Suppl. 1 (27 dicembre 2022): S11—S20. http://dx.doi.org/10.33549/physiolres.934954.

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It is well known that the mammalian uterine tube (UT) plays a crucial role in female fertility, where the most important events leading to successful fertilization and pre-implantation embryo development occur. The known functions of these small intra-abdominal organs are: an uptake and transport of oocytes; storage, transportation, and capacitation of spermatozoa, and finally fertilization and transport of the fertilized ovum and early embryo through the isthmus towards the uterotubal junction. The success of all these events depends on the interaction between the uterine tube epithelium (UTE) and gametes/embryo. Besides that, contemporary research revealed that the tubal epithelium provides essential nutritional support and the most suitable environment for early embryo development. Moreover, recent discoveries in molecular biology help understand the role of the epithelium at the cellular and molecular levels, highlighting the factors involved in regulating the UT signaling, that affects different steps in the fertilization process. According to the latest research, the extracellular vesicles, as a major component of tubal secretion, mediate the interaction between gametes/embryo and epithelium. This review aims to provide up-to-date knowledge on various aspects concerning tubal epithelium activity and its cross-talk with spermatozoa, oocytes and preimplantation embryo and how these interactions affect fertilization and early embryo development.

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Leese, H. J., e S. M. Gray. "Vascular perfusion: a novel means of studying oviduct function". American Journal of Physiology-Endocrinology and Metabolism 248, n. 5 (1 maggio 1985): E624—E632. http://dx.doi.org/10.1152/ajpendo.1985.248.5.e624.

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An in situ preparation for the combined vascular and luminal perfusion of the rabbit oviduct has been developed. Medium 199, gassed with 5% CO2 in O2 and supplemented with heparin, antibiotics, and 2.5% wt/vol dialyzed bovine serum albumin was infused into the ovarian artery at a rate of 1 ml/min. Krebs Ringer bicarbonate medium was recirculated through the lumen at a rate of 50 microliter/min. The ovary was perfused together with the oviduct, and the preparation is viable for up to 3 h. Equal concentrations of pyruvate, lactate, glucose, and sucrose added to the vascular medium were transported at different rates into the lumen, as was a physiological mixture of amino acids. A proportion of the lactate entering the lumen was synthesized within the oviduct from vascular glucose. When glucose and pyruvate were omitted from the vascular medium, their appearance and that of lactate in the lumen was barely detectable, suggesting that these oviduct fluid components are mainly derived from the blood. The oviduct maintained a steady transmural potential difference of 5.9 mV (lumen negative). With vascular perfusion alone, oviduct fluid entered the oviduct lumen at a rate of 16.8 microliter/h. In oviducts taken from rabbits 3 days postovulation, there was a general decrease in the vascular to lumen flux of all nutrients measured. Preliminary work has shown that the preparation may be used to study ovulation, ovum pickup and transport, and fertilization.

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Jemal, Jeilu, Tamrat Degefa, Tefera Yilma, Sayid Ali e Lemma Alemayehu. "Ovarian follicular dynamics in Boran and Crossbred heifers in Ethiopia: Implications for assisted reproductive techniques". Ethiopian Veterinary Journal 24, n. 2 (10 novembre 2020): 54–72. http://dx.doi.org/10.4314/evj.v24i2.4.

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The study was conducted to characterize the follicular dynamics of purebred Boran (Bos indicus) and Boran * Holstein Friesian crossbred heifers during estrous cycles; for use in ovum pick up and in-vitro embryo production. Insight of reproductive physiology of cattle would help to understand and exploit the reproductive potential of elite animals for breed improvement. Follicular development, growth and atresia during estrous cycles were evaluated using a trans-rectal real-time B-mode ultrasound system for three consecutive estrus cycles. Luteal activity was evaluated by serum progesterone level. Follicular aspirations were done to investigate the potential of Boran cattle and their crosses for transvaginal oocyte production; using a vacuum pressure pump and Aloka SSD Prosound-2 ultrasound device. Boran heifers (n=15) manifested two (n = 6, 40%), three (n = 5, 33%), four (n= 3, 20%) and five (n=1, 6.7%) follicular waves. Crossbred heifers (n=14) showed one (n= 2, 14%), two (n= 6, 43%) and three (n= 6, 43%) follicular waves. Interovulatory interval was 21.1 ± 3.4 and 21.4 ± 2.7 days for Boran (n=45) and crossbred (n=42) heifers, respectively. The progesterone level in Boran and Crossbred heifers during diestrus was 9.5 ± 11.0 and 4.6 ± 8.8 ng/ml, respectively. The maximum diameter of the ovulatory follicle for crossbred heifers was higher (15.4 ± 1.6 mm) than the diameter of the Boran (14.0 ± 1.9 mm) heifers (p<0.005). Differences (p<0.005) were observed in the size of both right (26.6 ± 5.14 and 28.6 ± 5.1 mm) and left (21.7 ± 4.85 and 24.1 ± 5.07 mm) ovaries of Boran and Crossbred heifers, respectively. Difference (p<0.005) was also observed in follicular count of the right ovaries of Boran (4.84 ± 1.96) and Crossbred (5.13 ± 2.05) heifers. Oocyte recovery rate in once weekly collection scheme for Boran and their crossbred heifers was (n=19, 42.08%) and (n=17, 42.55%), respectively. The recovery rate for twice weekly collection scheme was (n=24, 34.53%) and (n=23, 40.44%) for Boran and crossbred heifers, respectively. Follicular dynamics in Boran heifers is characterized by a higher incidence of cycles with two, three and four waves, associated with a low persistence of the dominant follicles; and smaller size of ovulatory follicles and less intense heat signs from their crossbred counterpart. Boran heifers proved to have potential for comparable number of follicular population and ease of aspiration procedures that can be tapped for advancedreproductive techniques. Keywords: Estrus cycle; follicular wave; ovarian follicle; ovum pickup; ultrasound.

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Wong, PY. "Abnormal fluid transport by the epididymis as a cause of obstructive azoospermia". Reproduction, Fertility and Development 2, n. 2 (1990): 115. http://dx.doi.org/10.1071/rd9900115.

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It has been known for more than a decade that in many mammalian species including man, spermatozoa once shed from the testis are immature, immotile and incapable of fertilizing the ovum. During their transit through the epididymis, they undergo various morphological and functional changes that confer on them the ability to ascend the female tract, to undergo an acrosome reaction, to penetrate the zona pellucida and to effect a successful fertilization. By the time spermatozoa have reached the cauda epididymidis, they are held in a quiescent state by factors in the epididymal fluid. The epididymis plays a vital role by creating a favourable fluid environment for sperm maturation and storage. The exact mechanisms underlying sperm maturation and storage are unclear and it appears that no single epididymal factor is held entirely responsible. In contrast, spermatozoa are directly bathed in the epididymal fluid; the fluidity of the microenvironmental has a direct effect on epididymal spermatozoa. The epididymal epithelium has been shown to transport electrolytes and water by processes involving ion pumps, ion carriers and ion channels. These components are under nervous, hormonal and paracrine control and are susceptible to interference by pharmacological agents. This paper reviews the physiology of electrolytes and fluid transport in the epididymis and describes how abnormal fluid transport across the epididymal duct could predispose towards epididymal obstruction, a condition that may occur in cystic fibrosis, Young's syndrome or other unexplained cases of male infertility.

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Tesi sul tema "Ovum Physiology"

Ying, Ying, e 應嬴. "Male accessory sex glands and oocyte activation at fertilization in the golden hamster". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31239663.

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Nottle, Mark Brenton. "Short-term nutrition and its effect on ovulation in the ewe". Title page, table of contents and summary only, 1988. http://web4.library.adelaide.edu.au/theses/09PH/09phn921.pdf.

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Seridi-Benkaddour, Ratiba. "Etude ultrastructurale et biochimique de la secretion de la goutte micropylaire par le nucelle au moment de la pollinisation chez quatre gymnospermes : thuya orientalis, cupressacees, cephalotaxus drupacea, cephalotaxacees, taxus baccata, taxacees". Paris 7, 1988. http://www.theses.fr/1988PA077152.

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Nottle, Mark Brenton. "Short-term nutrition and its effect on ovulation in the ewe / by Mark Brenton Nottle". Thesis, 1988. http://hdl.handle.net/2440/19113.

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Includes bibliographical references (leaves 143-165)
xiii, 168 leaves : ill. (some col.) ; 30 cm.
Reports on studies undertaken to examine the physiological basis of the known ability of lupin grain to increase ovulation rate in the ewe.
Thesis (Ph.D.)--University of Adelaide, Dept. of Animal Sciences, Waite Agricultural Research Institute, 1989

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Bagg, Melanie Anna. "Factors affecting the developmental competence of pig oocytes matured in vitro". 2007. http://hdl.handle.net/2440/42908.

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Pre-pubertal pig oocytes possess lower developmental competence than those from adult pigs following in vitro maturation (IVM). Previous studies have demonstrated that exposure of pre-pubertal oocytes to 1 mM dibutyryl cAMP (dbcAMP), a membrane permeable cyclic adenosine monophosphate (cAMP) analogue, for the first 20 h of IVM improves the rate of blastocyst development. Developmental competence of in vitro matured pig oocytes has been reported to increase with increasing follicle size. In this thesis, experiments were carried out using pre-pubertal and adult pig oocytes to investigate the relationship between donor age, intra-oocyte cAMP level and follicle size in terms of oocyte maturation and developmental competence. These experiments demonstrated that, while ovarian, follicular and oocyte morphology are immediately altered with the onset of puberty, pre-pubertal oocytes must be exposed to more than the first oestrous cycle to achieve improved developmental competence in vitro. Later experiments demonstrated that pre-pubertal oocytes accumulate less cAMP during IVM, undergo more rapid meiotic progression and display reduced rates of blastocyst development compared to in vitro matured adult oocytes. Treatment with dbcAMP for 22 h IVM increased the cAMP content of pre-pubertal oocytes, slowed meiotic progression during IVM and improved the rate of blastocyst formation. While the cAMP concentration of pre-pubertal oocytes was increased to levels similar to that of adult oocytes, rates of blastocyst formation remained lower, suggesting that additional factor(s) are required for oocyte maturation. This thesis also examined the follicle size cohorts that make up the 3-8 mm aspiration range on pig ovaries. The surface of pre-pubertal ovaries contained around double the number of 3 mm follicles compared with adult ovaries. Blastocyst development of pre-pubertal oocytes increased with increasing follicle size and was highest using oocytes from 5-8 mm follicles, while adult oocytes from all follicle size cohorts displayed similar high rates of blastocyst formation. The interaction between follicle size and cAMP content in pre-pubertal oocytes was examined next. Cumulus-oocyte complexes (COCs) from 3 mm follicles accumulated less intra-oocyte and inter-COC cAMP and displayed reduced cumulus expansion compared with COCs from 5-8 mm follicles. While dbcAMP treatment increased the cAMP content of oocytes from 3 mm follicles, it had no effect on the cAMP content of the whole COC. These findings suggest that inadequate levels of intra-oocyte cAMP during IVM contribute to the low developmental competence of pre-pubertal oocytes from 3 mm follicles, suggesting that cAMP transfer, production or degradation processes are incomplete. Analysis of steroid content from different follicle size cohorts revealed that the progesterone content of prepubertal follicular fluid (FF) increased with increasing follicle size, yet overall was lower than that of adults. This suggests that differences may exist in the gonadotropinstimulated steroidogenic activity of granulosa cells of pre-pubertal COCs from different follicle sizes. Since progesterone secretion did not differ between pre-pubertal and adult COCs, it appears that the downstream pathway from the granulosa cell response rather than the actual quantity of progesterone is important for subsequent maturation processes. These studies then examined gap junction communication (GJC) within the pre-pubertal COC during IVM to examine whether the positive effects of increasing follicle size and dbcAMP on intra-oocyte cAMP levels relates to improved cAMP transfer between the cumulus cell layer and oocyte. Cumulus cell-oocyte GJC during IVM was maintained for a longer period in pre-pubertal COCs from 3 mm follicles than in those from 5-8 mm follicles. Treatment with dbcAMP had minimal effect on GJC in either COC type, thus the dbcAMP-induced increase in intra-oocyte cAMP levels appears independent of GJC. Differences in GJC during IVM together with the COCs ability to increase intraoocyte cAMP levels during IVM, suggests that differences may exist in the quantity of gonadotropin receptors, which are responsible for cAMP production, within the cumulus layer of COCs from 3 mm compared with 5-8 mm follicles. In conclusion, this thesis has demonstrated that an increase in intra-oocyte cAMP is necessary during maturation for completion and synchronisation of maturation and high developmental competence of the pig oocyte. Comparison of 3, 4 and 5-8 mm follicle sizes in the pre-pubertal pig, as described here, provides an excellent model for further investigation into the role of cAMP and the other factors required for co-ordination of oocyte nuclear and cytoplasmic maturation and subsequent embryo production.
http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1297309
Thesis (Ph.D.) -- School of Paediatrics and Reproductive Health, 2007

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Libri sul tema "Ovum Physiology"

1932-, Yoshinaga Koji, Mori Takahide 1933- e International Congress of Endocrinology (8th : 1988 : Kyoto, Japan), a cura di. Development of preimplantation embryos and their environment: Proceedings of a Symposium on Development of Preimplantation Embryos and their Environment (satellite symposium of the 8th International Congress of Endocrinology), held in Kyoto, Japan, July 14-16, 1988. New York: A.R. Liss, 1989.

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Evers, Johannes Leonardus Henricus, 1949- e Heineman Maas Jan 1952-, a cura di. From ovulation to implantation: Proceedings of the VIIth Reinier de Graaf Symposium, Maastricht, the Netherlands, 30 May-2 June 1990. Amsterdam: Excerpta Medica, 1990.

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R, Barnea E., Parvensky Mary T e Society for Implantation and Early Pregnancy in Humans. World Conference, a cura di. Implantation and early pregnancy in humans: A combuned research and clinical approach. London: Parthenon Pub. Group, 1994.

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Paulesu, Luana Ricci. Signal molecules in animal and human gestation. Kerala, India: Research Signpost, 2004.

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J, Babin Patrick, Cerdà Joan 1965- e Lubzens Esther, a cura di. The fish oocyte: From basic studies to biotechnological applications. Dordrecht, the Netherlands: Springer, 2007.

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Loke, Y. W. Human implantation: Cell biology and immunology. Cambridge: Cambridge University Press, 1995.

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1949-, Chapman Michael, Grudzinskas J. G e Chard T, a cura di. Implantation: Biological and clinical aspects. London: Springer-Verlag, 1988.

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M, Beier H., Harper Michael J. K e Chwalisz K. 1952-, a cura di. The endometrium as a target for contraception. Berlin: Springer, 1997.

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Development of preimplantation embryos and their environment: Proceedings of a Symposium on Development of Preimplantation Embryos and their Environment ... in clinical and biological research). A.R. Liss, 1989.

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The placenta from implantation to trophoblastic disease: Apoptosis, proliferation, invasion, and pathology. Rochester, NY: University of Rochester Press, 1999.

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Capitoli di libri sul tema "Ovum Physiology"

Carr, Bruce R., e Victor E. Beshay. "Fertilization, Implantation, and Endocrinology of Pregnancy". In Textbook of Endocrine Physiology. Oxford University Press, 2011. http://dx.doi.org/10.1093/oso/9780199744121.003.0013.

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The complex and coordinated set of events leading to sperm and egg maturation and transport in the female genital tract that culminates in fertilization is one of the most remarkable phenomena in nature. This set of events is followed by the equally important unique processes of implantation, fetal maturation, and parturition. The hormonal changes that regulate these events are dependent on the close interaction of the fetal-placental-maternal unit. Just before ovulation, the egg, which has been arrested in the diplotene stage, completes the first meiotic division and forms the first polar body. The second meiotic division starts at the time of ovulation but ends only after fertilization by a sperm. The process of egg maturation is regulated through a closely interrelated set of hormonal events, most notably involving follicle-stimulating hormone (FSH), luteinizing hormone (LH), and estrogen. At the time of ovulation the fimbria of the oviduct are closely applied to the surface of the ovary. The extruded oocyte and adherent granulosa cells, known as the cumulus oophorus, is collected by the ciliated fimbrial end of the fallopian tube. The transport of the egg into the end of the fallopian tube occurs within minutes and is regulated primarily by ciliary action. The cumulus cells are able to communicate with one another via a network of intercellular bridges through the zona pellucida to the perivitelline space. The cumulus cells have also been reported to play a role in nutrition and maintenance of the ovum. There are three different stages of passage of the ovum through the fallopian tube. The first stage includes the transfer of the ovum from the fimbriated end of the fallopian tube until the egg reaches and is retained at the ampullary-isthmic junction. The ampullary-isthmic junction is a functional block but is not a clearly defined anatomical structure. The ovum remains at this junction for 1–2 days, during which time fertilization occurs.

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Mashamba, Tshililo. "Types of Multiple Pregnancy". In Multiple Pregnancy - New Insights [Working Title]. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.105788.

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Multiple pregnancy is condition where more than one offsprings are formed. This result from either fertilization of more than one ovum individually by separate sperms or division of fertilized ovum. The implantation sites may be in different part of the genital organs and even the peritoneal cavity. The physiology of monozygotic multiple pregnancy is not fully understood as the trigger has not yet been identified. The incidence of multiple pregnancy is increasing, and this is as a result of assisted reproductive technologies.

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Al-Rshoud, Firas, e Tamara Darwish. "Controlled Ovarian Stimulation". In Advances in Assisted Reproduction Technologies, 112–24. BENTHAM SCIENCE PUBLISHERS, 2022. http://dx.doi.org/10.2174/9789815051667122050006.

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For conception to occur, whether naturally or via assisted reproductive technology (ART), three things are required; a healthy sperm for fertilization, an ovum released from both ovaries (in the fallopian tubes for natural pregnancy or in the laboratory in IVF/ICSI), and a healthy place for the embryo to implant (a healthy receptive endometrial cavity), so any defect in any of the aforementioned pregnancy requirements will affect the achievement of pregnancy in both types; the natural one or that resulting from ART [1]. Ovarian stimulation is used to overcome any ovulatory disorder or in ART to collect as many eggs as possible (10-15 eggs at least) [2] to maximize the chances of pregnancy. Assessment of ovarian reserve is the first and most important step in ovarian stimulation, as this will indicate the proper method and dose needed for ovulation induction. We test for ovarian reserve using Biomarkers (FSH and AMH) and physical markers (antral follicles count(AFC)) by transvaginal ultrasound(TVS). Both AMH and AFC have similar accuracy in assessing ovarian reserve and are both superior to FSH as they have no cyclic variations [3]. This chapter will discuss all aspects of the physiology of the ovulation process and ovarian stimulation.

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Chenery-Morris, Sam, e Aileen Lynch. "Reproductive system". In Clinical Skills in Children's Nursing. Oxford University Press, 2010. http://dx.doi.org/10.1093/oso/9780199559039.003.0025.

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This chapter describes a number of clinical procedures related to the reproductive system that commonly occur in children. After completing this chapter you will have a working knowledge of the reproductive system and will have accomplished the following learning objectives. After reading this chapter you should be able to: ● Describe the anatomy of the female reproductive system including the external genitalia, the ovaries, the accessory reproductive structures, and the mammary glands. ● Describe the ovarian and menstrual cycles and the hormones that regulate them. ● Describe the anatomy of the male reproductive system including the external genitalia, the testes, the internal ducts, and the glands. ● Discuss the procedures involved in preparing the child for pelvic examination, demonstrating an awareness of the cultural, ethical, and legal implications of this examination. ● Explain and prepare the child for a swab procedure. ● Undertake the post-operative care of dressings on genitalia. Before embarking on this chapter it would be helpful to read through Chapter Two and Chapter Four, to provide you with relevant background skills required in this context. Informed consent and child protection are quite important related issues, and are covered in great detail in Chapter Four. The initial part of this chapter describes the anatomy and physiology of the reproductive system as a background towards understanding the relevant nursing care. This discussion is not intended to replace detailed study of anatomy and physiology, and for further and more detailed instruction on the topic you ought to consult a key text such as Martini & Nath (2008). The female reproductive system is regulated in a cyclical manner by hormones. The onset of the first menstrual cycle (menarche) occurs at puberty, and the female has the capacity to become pregnant up until the menopause, when the menstrual cycle ceases. The essential sex organs of the female reproductive system are the ovaries, which release one ovum (egg) each month. The fallopian tubes, uterus, vagina, and the mammary glands (breasts) make up the female accessory reproductive structures. The anatomy of the female reproductive system is illustrated in Figure 16.1.

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