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Microtubules and spermatogenesis
Seminars in Cell & Developmental Biology, 2014Microtubules are dynamic polymers of tubulin subunits that underpin many essential cellular processes, such as cell division and migration. Spermatogenesis is the process by which spermatogenic stem cells undergo mitotic and meiotic division and differentiation to produce streamlined spermatozoa capable of motility and fertilization.
O'Donnell, L., O'Bryan, M.
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2009
For many years androgens were thought to be the primary hormones required for proper functioning of the male reproductive system, and testes were shown to be the major producers of the hormone. In the 1970s it was recognized that in addition to androgens testes were also a source of estrogens, and the intratesticular concentration of estrogens was ...
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For many years androgens were thought to be the primary hormones required for proper functioning of the male reproductive system, and testes were shown to be the major producers of the hormone. In the 1970s it was recognized that in addition to androgens testes were also a source of estrogens, and the intratesticular concentration of estrogens was ...
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Epigenetics in spermatogenesis
Molecular and Cellular Endocrinology, 2009DNA methylation is a heritable epigenetic modification of cytosine residues within CpG dinucleotides associated with the modulation of gene expression and found at 20-30 million sites throughout the mammalian genome. The methylation of DNA is catalyzed by DNA (cytosine-5)-methyltransferases (DNMTs), regulates genes during development and plays a role ...
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1974
The effect upon spermatogenesis of subdermal silastic capsules containing testosterone in combination with various oral drugs was studied in groups of subfertile men. Group 1 received 25 mg norethisterone daily by mouth in conjunction with 6 norethindrone implants and 3 testosterone implants.
J, Frick, G, Bartsch
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The effect upon spermatogenesis of subdermal silastic capsules containing testosterone in combination with various oral drugs was studied in groups of subfertile men. Group 1 received 25 mg norethisterone daily by mouth in conjunction with 6 norethindrone implants and 3 testosterone implants.
J, Frick, G, Bartsch
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The intent of this chapter is to provide a morphological foundation in the normal cellular process of bovine gamete development so that abnormalities occurring are recognizable. The knowledge gained here is essential to begin to understand the significance of many of the common bull sperm abnormalities encountered in the clinics.
Albert, Barth +4 more
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Albert, Barth +4 more
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Fertility and Sterility, 2014
In mammals, male gametes are produced inside the testis by spermatogenesis, which has three phases: mitotic proliferation of spermatogonia, meiosis of spermatocytes, and haploid differentiation of spermatids. The genome of male germ cells is actively transcribed to produce phase-specific gene expression patterns.
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In mammals, male gametes are produced inside the testis by spermatogenesis, which has three phases: mitotic proliferation of spermatogonia, meiosis of spermatocytes, and haploid differentiation of spermatids. The genome of male germ cells is actively transcribed to produce phase-specific gene expression patterns.
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1987
Spermatogenesis is an intensively studied developmental process in Drosophila melanogaster and Drosophila hydei. Nonetheless, some phases of the development of the germ cells are still hardly understood. The main gap of information is with respect to the germ line-soma differentiation and the formation of the gonad.
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Spermatogenesis is an intensively studied developmental process in Drosophila melanogaster and Drosophila hydei. Nonetheless, some phases of the development of the germ cells are still hardly understood. The main gap of information is with respect to the germ line-soma differentiation and the formation of the gonad.
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Spermatogenesis in Cryptorchidism
2011Cryptorchidism or undescended testis is the most frequent congenital abnormality in newborn boys. The process of testicular descent to the scrotum is controlled by hormones produced in Leydig cells, insulin-like3, and androgens. Variation in genetic and environmental factors might affect testicular descent.
Alexander I, Agoulnik +2 more
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Microscopy Research and Technique, 1995
AbstractSpermatogenesis is a process of division and differentiation by which spermatozoa are produced in seminiferous tubules. A measure of efficiency of spermatogenesis is the estimated number of spermatozoa produced per day per gram of testicular parenchyma.
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AbstractSpermatogenesis is a process of division and differentiation by which spermatozoa are produced in seminiferous tubules. A measure of efficiency of spermatogenesis is the estimated number of spermatozoa produced per day per gram of testicular parenchyma.
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'Paracrine' control of spermatogenesis
Andrologia, 1999Spermatogenesis is a remarkably complex but precise process yielding highly differentiated haploid germ cells from diploid stem cells. Although many factors have been implicated in the paracrine control of spermatogenesis, functional proof is only available for a few regulators. Among those are androgens, growth factors and stem cell factor.
G F, Weinbauer, J, Wessels
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