Results 11 to 20 of about 331,784 (343)
Stem Cell Research & Therapy, 2018 Background Spermatogonial stem cell transplantation (SSCT) could become a fertility restoration tool for childhood cancer survivors. However, since in mice, the colonization efficiency of transplanted spermatogonial stem cells (SSCs) is only 12%, the ...
Prashant Kadam +5 more
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Comparative Transcriptome Analysis of Differentially Expressed Genes and Signaling Pathways between XY and YY Testis in Yellow Catfish. [PDF]
PLoS ONE, 2015 YY super-males have rarely been detected in nature and only been artificially created in some fish species including tilapia and yellow catfish (Pelteobagrusfulvidraco), which provides a promising model for testis development and spermatogenesis.
Junjie Wu +6 more
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Life, 2021 The sex chromosomes play central roles in determining the sex of almost all of the multicellular organisms. It is well known that meiosis in mammalian spermatogenesis produces ~50% Y- and ~50% X-chromosome-bearing sperm, a 1:1 ratio. Here we first reveal
Chengqing Hu +4 more
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Effect of competitive cues on reproductive morphology and behavioral plasticity in male fruitflies [PDF]
, 2015 Phenotypic plasticity will be favored whenever there are significant fitness benefits of responding to environmental variation. The extent and nature of the plasticity that evolves depends on the rate of environmental fluctuations and the capacity to ...
Bretman, Amanda +3 more
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Testicular endocrine activity is upregulated by D-Aspartic acid in the green frog Rana esculenta [PDF]
, 2004 This study investigated the involvement of D-aspartic acid (D-Asp) in testicular steroidogenesis of the green frog Rana esculenta and its effect on stimulation of thumb pad morphology and glandular activity, a typical testosterone-dependent secondary ...
ASSISI, LOREDANA +5 more
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Spermatogonial stem cells as a source for regenerative medicine
Middle East Fertility Society Journal, 2012 Several researchers have reported the derivation of multipotent cells from both mouse and human spermatogonial stem cells. These spermatogonia-derived stem cells show similarities with embryonic stem cells both for phenotype and functionality, indicating
Liang Ning +4 more
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Sperm competition and sperm midpiece size: no consistent pattern in passerine birds [PDF]
, 2007 Sperm competition is thought to be a major force driving the evolution of sperm shape and function. However, previous studies investigating the relationship between the risk of sperm competition and sperm morphometry revealed inconclusive results and ...
Birkhead T.R +3 more
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Larger testes are associated with a higher level of polyandry, but a smaller ejaculate volume, across bushcricket species (Tettigoniidae) [PDF]
, 2010 While early models of ejaculate allocation predicted that both relative testes and ejaculate size should increase with sperm competition intensity across species, recent models predict that ejaculate size may actually decrease as testes size and sperm ...
Darren J. Parker +3 more
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Plasma and testicular testosterone levels, volume density and number of Leydig cells and spermatogenic efficiency of rabbits [PDF]
, 2002 Plasma and tissue testosterone concentrations were determined by radioimmunoassay in 12 eight-month-old sexually mature New Zealand White rabbits and evaluated for possible associations with spermatogenic efficiency as well as with volume density and ...
Berndtson, William E. +2 more
core +2 more sources
Clinical Medicine Insights: Reproductive Health, 2019 Young boys undergoing gonadotoxic treatments are at high risk of spermatogonial stem cell (SSC) loss and fertility problems later in life. Stem cell loss can also occur in specific genetic conditions, eg, Klinefelter syndrome (KS).
Aude Braye +2 more
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