Results 191 to 200 of about 20,184 (239)

Round spermatid injection

Fertility and Sterility, 2000
This finding has caused great concern with round spermatid enthusiasts. A major complaint is that “one should not restrict the label of round spermatid only to those cells in which an acrosomal vesicle is visible” (p. 2977) (4). However, our observation is based not only on phase-contrast evaluation of TESE microdroplets but also on detailed stained ...
Silber, Sherman, Johnson, Larry, Verheyen, Greta, Van Steirteghem, Andre   +3 more
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Spermatids as male gametes

Reproduction, Fertility and Development, 1995
Intracytoplasmic sperm injection (ICSI) is becoming increasingly popular in human infertility clinics as an efficient method for the treatment of male infertility. It is proposed that spermatids can be used as substitutes for spermatozoa if men are unable to produce sperm in their testes.
A, Ogura, R, Yanagimachi
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Transformation of ram spermatid chromatin

Experimental Cell Research, 1978
Abstract In order to investigate the sequence of changes in nuclear basic proteins throughout ram spermiogenesis, we have used different techniques to obtain populations of spermatid nuclei in specific stages of maturation. Sedimentation of testis cells at 1 gravity followed by treatment with Triton X-100 resulted in one population of round spermatid
M, Loir, M, Lanneau
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Mouse Round Spermatid Injection

Journal of Visualized Experiments
Round spermatids, characterized by their haploid genetic content, represent the precursor cells to mature spermatozoa. Through the innovative technique of round spermatid injection (ROSI), oocytes can be successfully fertilized and developed into viable fetuses. In a groundbreaking milestone achieved in 1995, the first mouse fetus was born through ROSI
Haibo, Zhu, Yuting, Jiang, Haiwei, Quan, Leyi, Li, Jiarui, Wei, Ruizhi, Liu, Ruixue, Wang   +6 more
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Nuclear reorganization in ram spermatids

Journal of Ultrastructure Research, 1979
Nuclear changes as a function of ram spermatid differentiation have been studied using electron microscopy, cytochemistry, and treatment of isolated nuclei with chemical and mechanical agents. In round nuclei, chromatin consists of intertwined knobby fibers about 210 and 120 A in diameter.
M, Loir, J L, Courtens
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Hormonal regulation of spermatid binding

Journal of Cell Science, 1991
ABSTRACT A Sertoli-spermatid coculture model is described in which a large percentage (>76%) of round spermatids remain viable for 48 h and bind to Sertoli cells. The effects of follicle-stimulating hormone (FSH) and testosterone on spermatid binding (expressed as the spermatid density; SD- the number of spermatids per unit area ...
D F, Cameron, K E, Muffly
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Motile Components in Spermatids as Related to Transport of Spermatids and Spermatozoa*

Andrologia, 2009
Two distinctly different components of motility were detected in living early spermatids of the rat using phase contrast microscopy and video-analysis: the primary flagellum (a 9 + 2 axonema) executes wave-like motion in three dimensions. At the same time the flagellum displays alternatively in clockwise and counter-clockwise directions partial torsion,
H, Walt, C, Hedinger
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Density separation of mouse spermatid nuclei

Experimental Cell Research, 1972
Abstract The buoyant density of the spermatid nucleus increases dramatically during spermiogenesis in the mouse. Cells from the mouse testes were first separated by velocity sedimentation at unit gravity. All cells with sedimentation velocities of less than 3 mm/h were treated with a cationic detergent to obtain a suspension of nuclei.
Loir, M, Wyrobek, A
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Nuclear shaping in marsupial spermatids

Journal of Ultrastructure Research, 1972
Nuclear shaping was investigated in two species of American opossum, Didelphus virginiana and Marmosa mitus. The mature spermatozoan head achieves its “U” shaped form by the progressive flattening of the posterior margin of the nucleus and the development of a protrusion on one side of the nucleus.
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Ultrastructural Characteristics of Idiopathic Spermatidic Arrest

Archives of Andrology, 1979
Previous studies on some cases of idiopathic spermatidic arrest showed an anomaly in glucose metabolism, in particular decreased utilization of glycogen at stage 3 of spermatogenesis, when condensation of the spermatid head commences. Histological patterns seen on light microscopy confirmed the reduced utilization of glycogen at stage 3 of ...
M, Re, F, Carpino, G, Familiari, M, Iannitelli, A, Vicari   +4 more
openaire   +2 more sources