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[Epigenetics of the sperm cell].
Gynecologie, obstetrique & fertilite, 2006In addition to genetic information, the spermatozoon carries another type of information, named epigenetic, which is not associated with variations of the DNA sequence. In somatic cells, it is now generally admitted that epigenetic information is not only regulated by DNA methylation but also involves modifications of the genome structure, or epigenome.
S, Rousseaux +9 more
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Journal of Experimental Biology, 2017
![Graphic][1] Animals face stressful environments in the wild. When the going gets rough, parents can prepare their developing offspring for life in a tough world. They can alter gene expression patterns in their young to best ‘match’ their babies’ physical characteristics to their ...
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![Graphic][1] Animals face stressful environments in the wild. When the going gets rough, parents can prepare their developing offspring for life in a tough world. They can alter gene expression patterns in their young to best ‘match’ their babies’ physical characteristics to their ...
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Penetration of Somatic Mammalian Cells by Sperm
Science, 1974Penetration of somatic mammalian cells by spermatozoa occurred after simple admixture in culture. With sperm labeled in vivo, autoradiography revealed incorporation of DNA into nuclei of recipient cells, indicating release of DNA after entrance by sperm.
A, Bendich +2 more
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1972
Publisher Summary The spermatozoon of insects has evolved in the direction of increased motility—its shape, structure, metabolism, and locomotory capabilities are tremendously differentiated. In many instances they attain an extreme specialization which is related to: (1) the mode of sperm transmission (internal fertilization always being the case); (
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Publisher Summary The spermatozoon of insects has evolved in the direction of increased motility—its shape, structure, metabolism, and locomotory capabilities are tremendously differentiated. In many instances they attain an extreme specialization which is related to: (1) the mode of sperm transmission (internal fertilization always being the case); (
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Detection of damage in mammalian sperm cells
Theriogenology, 2006Ejaculated semen is washed for in vitro fertilization or diluted and processed to allow optimal and long-term low temperature liquid- and cryo-preservation. However, sperm are vulnerable to the washing, dilution, temperature and osmotic changes involved in sperm storage.
da Silva, P.F.N., Gadella, B.M.
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2002
At least one third of human germ cells are carrying a chromosomal abnormality resulting from errors in meiosis. These chromosomal abnormalities often result in early abortions and sometimes in the birth of a disabled child. Since 1978 it has been possible to karyotype human sperm cells by reactivating them with hamster ova (Rudak et al. 1978). However,
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At least one third of human germ cells are carrying a chromosomal abnormality resulting from errors in meiosis. These chromosomal abnormalities often result in early abortions and sometimes in the birth of a disabled child. Since 1978 it has been possible to karyotype human sperm cells by reactivating them with hamster ova (Rudak et al. 1978). However,
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Testicular Contractile Cells and Sperm Transport
Fertility and Sterility, 1977Information bearing on the presence function and possible physiologic control of the contractile cells of the testis is consolidated. The cells are true muscle cells and contractile fibroblasts. Smooth muscle is most important in capsules of rabbits and dogs less so in humans and rats.
J L, Hargrove, J H, MacIndoe, L C, Ellis
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2001
The generative cell and sperm spend their natural lives encased by the vegetative cell. The generative cell is formed at the first division of the microspore and divides in the pollen grain or pollen tube to form two sperm cells. Thus, the generative cell is never “free” of the vegetative cell in which it is embedded.
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The generative cell and sperm spend their natural lives encased by the vegetative cell. The generative cell is formed at the first division of the microspore and divides in the pollen grain or pollen tube to form two sperm cells. Thus, the generative cell is never “free” of the vegetative cell in which it is embedded.
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The nuclear status of human sperm cells
Micron, 1995In the last decade, and in particular since the development of in vitro fertilization techniques, the nuclear status of human sperm cells has shown to be a key parameter in the assessment of male fertility. The shape and condensed state of the mature sperm nucleus are determined by structural and functional events that occur during spermiogenesis. This
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1988
Two types of sperm cells are found in mature pollen grains of Apiaceae. For example Eryngium campestre (Fig.l) shows the plasma-rich sperm cell type having numerous organelles, mainly mitochondria and dictyosomes. The mitochondria (m) are smaller than those in the vegetative cytoplasm (M). The nucleus is elongated and slightly sickle-shaped. The folded
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Two types of sperm cells are found in mature pollen grains of Apiaceae. For example Eryngium campestre (Fig.l) shows the plasma-rich sperm cell type having numerous organelles, mainly mitochondria and dictyosomes. The mitochondria (m) are smaller than those in the vegetative cytoplasm (M). The nucleus is elongated and slightly sickle-shaped. The folded
openaire +1 more source