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Reviews of Reproduction, 1999
Communication between spermatozoa and egg before contact by chemotaxis appears to be prevalent throughout the animal kingdom. In non-mammalian species, sperm chemotaxis to factors secreted from the egg is well documented. In mammals, sperm chemotaxis to follicular factors in vitro has been established in humans and mice.
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Communication between spermatozoa and egg before contact by chemotaxis appears to be prevalent throughout the animal kingdom. In non-mammalian species, sperm chemotaxis to factors secreted from the egg is well documented. In mammals, sperm chemotaxis to follicular factors in vitro has been established in humans and mice.
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Sperm competition influences sperm size in mammals
Proceedings of the Royal Society of London. Series B: Biological Sciences, 1991Among mammals sperm competition leads to selection for increased sperm numbers but it is not known whether it also leads to changes in sperm size. Two contrasting theoretical predictions have been made. The first hypothesis relies on the assumption that there is a trade-off between sperm numbers and sperm size and predicts that, in species confronting ...
Eduardo R. S. Roldan +1 more
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SPERM ACROSOME STATUS AND SPERM ANTIBODIES IN INFERTILITY
Journal of Urology, 1998We studied whether the spermatozoa from sperm autoimmune infertile men undergo premature acrosomal loss and whether this relates to the presence of sperm antibodies in wives.We evaluated acrosome status of live washed native and overnight capacitated spermatozoa from 17 sperm nonautoimmune fertile and 23 sperm autoimmune infertile men using an ...
Steven Harrison +2 more
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SPERM COMPETITION AND THE EVOLUTION OF NONFERTILIZING SPERM IN MAMMALS
Evolution, 1991Nonfertilizing sperm with special morphologies have long been known to exist in invertebrates. Until recently, abnormal sperm in mammals were considered errors in production. Now, however, Baker and Bellis (1988, 1989) have proposed that mammalian sperm, like some invertebrate sperm, are polymorphic and adapted to a variety of nonfertilizing roles in ...
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Intracytoplasmic sperm injection
Molecular and Cellular Endocrinology, 2002Intracytoplasmic sperm injection (ICSI) with ejaculated, epididymal or testicular spermatozoa was first successful in 1992 and has since become the widely accepted treatment for couples with severe male-factor infertility. The outcome of several thousands of ICSI cycles in terms of fertilization, embryo cleavage and implantation is similar to that for ...
Van Steirteghem, André +2 more
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The risk of sperm competition and the evolution of sperm heteromorphism
Animal Behaviour, 1998Members of the Drosophila obscura species group exhibit sperm heteromorphism in which males simultaneously produce two different morphologies of sperm, short and long. Short sperm represent at least 50% of the ejaculate in several species but do not function in fertilization and thus, the evolutionary significance of this phenomenon is unknown ...
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Donor sperm for intracytoplasmic sperm injection
The Lancet, 2001C. Yaman, M. Moser, T Ebner, G Tews
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Testes, Sperm, and Sperm Competition
2009Robert Montgomerie, John L. Fitzpatrick
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Surgical sperm retrieval for intracytoplasmic sperm injection.
International journal of andrology, 1997The introduction of intracytoplasmic sperm injection (ICSI) provides new hope for many couples suffering from the most untreatable forms of male infertility as ICSI can also be successfully performed using epididymal or testicular spermatozoa. Testicular spermatozoa may be recovered from testicular tissue in every patient with excretory azoospermia ...
Tournaye, Herman +6 more
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Sperm Stories: Sociotechnical Imaginaries of Sperm Donation and Sperm Banking in Denmark
2016openaire +3 more sources