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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Efficacy of psychosocial group intervention for Chinese women undergoing in-vitro fertilization: aprospective randomized controlled study

Chan, Hoi-yan, Celia, 陳凱欣 January 2010 (has links)
published_or_final_version / Social Work and Social Administration / Doctoral / Doctor of Philosophy
22

Activation of bovine oocytes following intracytoplasmic sperm injection (ICSI)

Chung, Jin-Tae, 1961- January 1999 (has links)
The objective of this study was to develop a reliable method for intracytoplasmic sperm injection (ICSI) in bovine oocytes. Oocytes recovered from abattoir-derived ovaries were centrifuged for 5 min at 6000xg to facilitate sperm injection. Sperm were pre-treated in vitro with 5mM dithiothreitol (DTT), and diluted (approximately 1:5) with 5% polyvinylpyrrolidone (PVP) in 0.9% saline. After sperm injection, various activation procedures were compared. Initially, 3 h after activation with 5muM Ionomycin (A23187), oocytes with second polar bodies were selected and treated with 1.9mM 6-dimethylaminopurine (DMAP). The cleavage rate of sperm-injected oocytes treated with Ionomycin and DMAP was higher than with Ionomycin alone (62.1 vs. 27.3%, p < 0.05). In sham-injected control oocytes treated with Ionomycin and DMAP, the cleavage rate was approximately six times higher than that of oocytes treated with Ionomycin alone (44.3 vs. 7.4%, p < 0.001). Upon examination 16 h after ICSI, pronuclear formation was observed in 33 of 47 (70.2%) DMAP-treated oocytes. Two pronuclei were present in 18 of 33 (54.6%), while one and three pronuclei were seen in 8 of 33 (24.2%) and 7 of 33 (21.2%), respectively. In sham-injected DMAP-treated control oocytes, 6 of 15 (40.0%) had one pronucleus while 9 of 15 (60.0%) had two pronuclei. Since a single Ca2+ stimulation provided insufficient activation and DMAP treatment could result in triploidy, activation by multiple Ca2+ stimulations following ICSI was tested. Three Ca2+ stimulations were given at 30-min intervals. Pronuclear formation was observed in 16 of 41 (39.0%) oocytes at 16 h after sperm injection, with one and two pronuclei found in 4 of 16 (25.0%) and 12 of 16 (75.0%), respectively. Although one pronucleus was formed in 3 of 33 (9.1%) sham-injected control oocytes treated with three Ca2+ stimulations, two pronuclei were not seen in any of these oocytes. Due to the low rate of pronuclear formation after 5muM Ionomycin, 50muM
23

Developmental competence of prepubertal and adult goat oocytes cultured in semi-defined media

Koeman, Jennifer. January 2000 (has links)
In vitro production of embryos from oocytes recovered by laparoscopic oocyte pick-up (LOPU) offers great potential for the propagation of genetically valuable animals. In turn, the application of these techniques to prepubertal animals presents added benefits in that prepubertal animals may supply a greater number of oocytes than adult animals. The aim of the present study was to evaluate the developmental competence of prepubertal and adult goat oocytes cultured in semi-defined media. The follicular response and recovery of oocytes via LOPU from hormonally stimulated prepubertal and adult goats were also assessed. / Oocytes were collected over a 15-wk period from prepubertal goats, ranging in age between 3--7 mo, and adult controls, ranging in age between 2--4 yr, randomly divided into 10 collection groups. Oocytes from six of the ten collections were matured for 26 h. Four collections were not completed due to technical difficulties. Following insemination, zygotes were cultured for 4 d in G1.2 followed by 4 d in G2.2. Morulae and blastocysts were scored via light microscopy on Days 7 and 9, followed by fluorescent staining on Day 9 for cell counts. (Abstract shortened by UMI.)
24

Studies on the differences between in-vivo and in-vitro matured mouse oocytes priming with or without gonadotropins

Wang, Yue, 1973 Aug. 1- January 2007 (has links)
Acquisition of full developmental competence of oocytes not only occurs during growth stage, and the final preparation during oocyte maturation is also critical. Previous studies have shown that nuclear maturation can occur spontaneously following culture in vitro; however, there may be some insufficiency in cytoplasmic maturation of the in vitro matured oocytes. But till now, the differences of the events of cytoplasmic maturation between in vitro and in vivo matured oocytes are still not clear. Ovarian stimulation by gonadotrophins is used to permits the growth and development of follicles, to time the initiation of pre-ovulatory oocyte maturation, and to increase the numbers of oocytes ovulated. It is one of the foundations of current treatments of human infertility. The success of clinical IVF has been depending on generation of matured oocytes at high frequency. However, ovarian stimulation with gonadotropins is associated with side effects and complications. / In order to illuminate mechanisms which affect the developmental competence of oocytes produced in vitro, in the present study, we have compared the difference of the quality of oocytes produced in vitro with that of the oocytes produced in vivo using mouse model. In order to understand the relationship between oocyte competence and ovarian responses to stimulation in the mouse, we also have compared difference of the quality of oocytes produced in vitro or in vivo from gonadotrophns stimulated ovaries with that of from natural cycling ovaries. / In-vitro matured oocytes were collected from (1) naturally ovulated mice and (2) superovulated (PMSG + hCG) mice. Immature oocytes were retrieved from (3) naturally cycling mice, and (4) from mice primed with PMSG. The results indicate that the percentages of cleavage and blastocyst formation are significantly different (P&lt;0.05) between in-vivo and in-vitro matured oocytes. Blastocyst formation rate is significantly higher (P&lt;0.05) in immature oocytes derived from PMSG primed mice compared to immature oocytes derived from naturally cycling mice. The percentages of oocytes with comet tails and the length of comet tails are significantly higher and longer respectively in in-vitro matured oocytes compared to in-vivo matured oocytes. Total cell numbers of blastocyst are also significantly different (P&lt;0.05) between in-vivo and in-vitro matured oocytes. However, there are no differences in ratio of trophectoderm (TE)/inner cell mass (ICM) between in-vivo and in-vitro matured oocytes. In conclusion, in-vivo matured mouse oocytes are more competent than those of matured in-vitro, suggesting that it may be due to its less damage of DNA. Embryonic development capacity of in-vivo matured oocytes is not promoted by ovarian stimulation. Gonadotropin priming prior to immature mouse oocyte retrieval is beneficial to subsequent embryonic development. / Keywords. mouse oocyte, IVM, IVF, gonadotropin, development
25

The role of the cumulus oophorus complex during spermatozoa capacitational events /

Rijsdijk, Michelle. January 2005 (has links)
Thesis (MScMed)--University of Stellenbosch, 2005. / Bibliography. Also available via the Internet.
26

Expression of hypoxia-inducible factors during bovine preimplantation embryo development /

Harvey, Alexandra Juanita. January 2003 (has links) (PDF)
Thesis (Ph.D.)--University of Adelaide, Dept. of Obstetrics and Gynaecology, 2004. / "December 2003" Includes bibliographical references (leaves 183-224).
27

Intracytoplasmic sperm injection overcomes previous fertilization failure with conventional in vitro fertilization /

Siano, Linda J. January 2000 (has links)
Thesis (M.A.)--Central Connecticut State University, 2000. / Thesis advisor: Kathy Martin. " ... in partial fulfillment of the requirements for the degree of Master of Arts in Biological Sciences." Includes bibliographical references (leaves 23-27).
28

The association between foot-and-mouth disease virus and bovine oocytes and embryos during in vitro embryo production

Jooste, Frans. January 2005 (has links)
Thesis (MMedVet (Gyn))--University of Pretoria, 2005. / Includes bibliographical references.
29

Studies on the cryopreservation of boar spermatozoa and its integration into assisted reproductive technologies

Bathgate, Roslyn. January 2004 (has links)
Thesis (Ph. D.)--Faculty of Veterinary Science, University of Sydney, 2005. / Title from title screen (viewed 13 January 2009). Degree awarded 2005; thesis submitted 2004. Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the Faculty of Veterinary Science. Includes bibliographical references. Also available in print form.
30

An evaluation of the use of G-CSF as an adjunct to IVF in women who have previously failed attempts at pregnancy with IVF

Mohamed, Tasneem January 2017 (has links)
A research report submitted to the Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, in partial fulfillment of the requirements for the degree of Master of Medicine in the branch of Obstetrics and Gynaecology. Johannesburg, 2017 / Background Recurrent IVF failures may result from implantation defects of which a thin endometrium is often implicated. Studies show that improved endometrial thickness increases the probability of successful IVF. Objectives To evaluate the effects of transcervical instillation of G-CSF as an adjunct to IVF. The study looked at the influence of G-CSF on the endometrium and on the achievement of pregnancy. Methods A retrospective cross-sectional study of women attending Bio ART Fertility Centre, who had two or more failed IVFs previously. Results There were a total of 49 women studied with a mean age of 38.9. Mean number of previous IVFs were 3.1. Comparison between those that achieved pregnancy and those that did not showed that age was a statistically significant factor (p-value 0.0005). Mean endometrial thickness pre and post-GCSF between the groups was not statistically significant (p-values >0.05). Conclusion With the use of G-CSF we achieved a clinical pregnancy rate of 34.69% and a statistically significant overall expansion of endometrial thickness (p-value 0.0029). However we failed to show any association between endometrial expansion and pregnancy outcome. / MT 2018

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