Results 271 to 280 of about 53,055 (306)

Regulation of amphibian oocyte maturation

Cell Differentiation, 1985
Xenopus oocyte maturation is a model system for studying the control of cell proliferation and the regulation of the cell cycle. Addition of progesterone or insulin to oocytes releases a G2 block and stimulates progression through meiosis to an unfertilized egg.
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In vitro maturation of horse oocytes

Theriogenology, 1994
Ovaries collected from slaughtered mares of unknown reproductive history were transported to the laboratory, and their oocytes were recovered and cultured in modified TCM 199 supplemented with 20% horse serum and additional granulosa cells. To characterize the ovaries, the size and number of follicles were counted.
H, Alm, H, Torner
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Regulation of Oocyte Maturation

Annals of the New York Academy of Sciences, 1988
We suggest that cAMP is a key molecule in regulation of oocyte maturation. In the small follicle, tonic levels of cAMP are continuously transferred to the oocytes to maintain meiotic arrest. In the preovulatory follicle, in response to LH, cAMP levels are elevated.
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Folloicular dominance and oocyte maturation

Zygote, 1996
The ovulatory follicle has the dual role of releasing a viable oocyte capable of fertilisation and the production of key endocrine signals that result in mating behaviour, the induction of the preovulatory LH surge and ovulation. Further, following ovulation the ovulatory follicle must be capable of forming a viable corpus luteum if pregnancy is to be ...
B K, Campbell, A S, McNeilly
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Maturation and Fertilization of Equine Oocytes

Veterinary Clinics of North America: Equine Practice, 1996
Equine oocytes obtained either by transvaginal ultrasound-guided follicular aspiration or from slaughterhouse ovaries can be matured in vitro. This generally requires culture in TCM-199 containing serum and hormones for 30 to 36 hours. With this protocol, approximately 50% to 60% of the oocytes are at metaphase-II at the end of the culture period.
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Maturation and Fertilization in Starfish Oocytes

1984
L'ignorance qui estoit naturellement en nous, nous l'avons, par longue estude, confirmee et averee. (MONTAIGNE)Sorrow is knowledge; they who know the most Must mourn the deepest o'er the fatal truth The Tree of knowledge is not that of Life. (BYRON)
L, Meijer, P, Guerrier
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Mature oocyte cryopreservation: a guideline

Fertility and Sterility, 2013
There is good evidence that fertilization and pregnancy rates are similar to IVF/ICSI with fresh oocytes when vitrified/warmed oocytes are used as part of IVF/ICSI for young women. Although data are limited, no increase in chromosomal abnormalities, birth defects, and developmental deficits has been reported in the offspring born from cryopreserved ...
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Mechanisms of Xenopus oocyte maturation

1997
Publisher Summary This chapter discusses the mechanisms of xenopus oocyte maturation. Although many aspects of the meiotic cell cycle are similar to the mitotic cell cycle, the differences between them are critical for the accurate reduction of genetic material.
M S, Murakami, G F, Vande Woude
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Recurring themes in oocyte maturation

Biology of the Cell, 1998
I am pleased to contribute to this special issue of Biology of the Cell in honor of Yoshio Masui. Oocyte maturation remains a small enough and young enough field that the authors assembled for this issue can trace the entire development of the field over the last 30 years, beginning with the early demonstration by Masui (1967) and others that steroids ...
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[Oocyte maturation: can oocyte competence be defined?].

Journal de gynecologie, obstetrique et biologie de la reproduction, 2006
Oocyte competence is acquired throughout oogenesis, via the interaction with somatic cells. The ability to reinitiate the meiotic process and undergo preimplantation development is progressively determined during the antral phase. It is well-known that these changes involve the nuclear and cytoplasmic compartments, respectively, but the underlying ...
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