Results 201 to 210 of about 52,517 (253)

Sea Urchin Spermatozoa

2004
Publisher Summary The chapter describes the structures and functions of sea urchin spermatozoa. Methods for the isolation of different parts of the sea urchin sperm are discussed. Sea urchin sperm are specialized for five functions: (1) oxidative phosphorylation to produce ATP, (2) flagellar motility, (3) the acrosome reaction, (4) binding to the egg,
Victor D, Vacquier, Noritaka, Hirohashi
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Cryopreservation of Stallion Spermatozoa

Veterinary Clinics of North America: Equine Practice, 1996
The main advantage to using frozen semen in any breeding program is faster genetic gain for the inherited trait desired. Milk production of dairy cows doubled (from 26,000 to 52,000 kg of milk/cow per year) between 1950 and 1980, because the dairy industry was using semen only from bulls with the greatest genetic potential for milk production.
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Cryopreservation of Kangaroo Spermatozoa [PDF]

, 2023
Kangaroo spermatozoa have proven extremely difficult to cryopreserve such that despitenumerous empirical studies using high concentrations of glycerol and/or DSMO, the bestpost-thaw motility has only been in the order of 10%. The efficacy of glycerol as acryoprotectant for marsupial spermatozoa is somewhat paradoxical, being necessary athigh ...
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ACETYLCHOLINESTERASE IN BULL SPERMATOZOA

Reproduction, 1964
Summary. Acetylcholinesterase occurs in the head, midpiece and tail fractions of sonically disrupted bull epididymal spermatozoa. The enzyme exhibits the characteristic substrate concentration optimum; 1·5 × 10-5 m-eserine competitively inhibits the hydrolysis of the acetylcholine.
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Spermatozoa in the Peak District

Molecular Reproduction and Development, 2015
imageMol. Reprod. Dev. 83: 8–11, 2016. © 2015 Wiley Periodicals, Inc.
Mariana F, Wolfner, Robert, Montgomerie
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Spermatozoa repellent as a contraceptive

Contraception, 1979
Early report by Kopp et al. have demonstrated that p-nitrophenyl-glycerol (PNPG) is an effective antiswarming agent in Proteus and that this inhibition may have been caused by PNPG interfering with the negative chemotaxis mechanism in the organism. With an inverted capillary assay, designed to test the motility response of rat epididymal spermatozoa to
W W, Tso, W M, Lee, M Y, Wong
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Screening for canine spermatozoa

Science & Justice, 2001
A case is presented in which possible canine spermatozoa were encountered in the routine examination of sexual assault evidence. Some observations and difficulties concerning the detection of canine spermatozoa are discussed. A possible visual screening method for canine sperm cells is offered, involving conventional forensic/histological staining ...
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Chemotaxis of Rabbit Spermatozoa

Journal of Experimental Biology, 1963
ABSTRACT The aim of the study was to determine whether rabbit eggs’attract’ homologous spermatozoa in vivo. Preliminary experiments showed that, in vitro, rabbit spermatozoa readily and irreversibly attach to the zonae of rat eggs.
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Fate of Unejaculated Spermatozoa

Nature, 1967
THE production of spermatozoa does not cease in sexually inactive males1–3, and it becomes necessary to examine the means of disposal of the surplus spermatozoa. The two most likely ways are either that they are voided in the urine or that they are resorbed in the epididymis or vas deferens.
B F, Lino, A W, Braden, K E, Turnbull
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Pathophysiology of human spermatozoa

Current Opinion in Obstetrics and Gynecology, 1994
Our capacity to diagnose the functional competence of human spermatozoa has been facilitated by recent advances in our understanding of sperm physiology. This review focuses on two important developments, namely the role of lipid peroxidation in the pathophysiology of impaired sperm function and the extragenomic action of progesterone in controlling ...
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