Results 21 to 30 of about 489,854 (362)
Sperm Competition, Sperm Numbers and Sperm Quality in Muroid Rodents
PLoS ONE, 2011 Sperm competition favors increases in relative testes mass and production efficiency, and changes in sperm phenotype that result in faster swimming speeds. However, little is known about its effects on traits that contribute to determine the quality of a whole ejaculate (i.e., proportion of motile, viable, morphologically normal and acrosome intact ...
Laura Gómez Montoto +7 more
openaire +4 more sources
Evolution of sperm size in nematodes: sperm competition favours larger sperm [PDF]
Proceedings of the Royal Society of London. Series B: Biological Sciences, 1999 In the free-living rhabditid nematode Caenorhabditis elegans, sperm size is a determinant of sperm competitiveness. Larger sperm crawl faster and physically displace smaller sperm to take fertilization priority, but not without a cost: larger sperm are produced at a slower rate. Here, we investigate the evolution of sperm size in the family Rhabditidae
C W, LaMunyon, S, Ward
openaire +2 more sources
Cryopreservation of common carp sperm [PDF]
, 2003 Experiments were carried out to investigate the effect of five extenders (sucrose, glucose, fructose, KCl and a saline carp sperm extender) and two cryoprotectants (dimethyl-sulfoxide (DMSO) and methanol) on the cryopreservation of common carp sperm ...
Urbányi, Béla +5 more
core +1 more source
Therapeutic Effects of Prolonged Release Melatonin (Circadin) in Patients with Overactive Bladder and Chronic Insomnia in More Than 55 Years Old [PDF]
Kosin Medical Journal, 2020 Objectives Bladder storage symptoms including nocturia is the most common cause of sleep disturbance in all age groups. Sleep disturbance is also a main cause of nocturia so that sleep recovery can clinically improve nocturia.
Min Jung Park +5 more
doaj +1 more source
Hydrodynamic propulsion of human sperm [PDF]
, 2009 The detailed fluid mechanics of sperm propulsion are fundamental to our understanding of reproduction. In this paper, we aim to model a human sperm swimming in a microscope slide chamber.
Green, Richard B. +7 more
core +1 more source
How sperm competition shapes the evolution of testes and sperm: a meta-analysis
Philosophical Transactions of the Royal Society of London. Biological Sciences, 2020 Females of many species mate with multiple males, thereby inciting competition among ejaculates from rival males for fertilization. In response to increasing sperm competition, males are predicted to enhance their investment in sperm production.
S. Lüpold +4 more
semanticscholar +1 more source
Molecular Analysis of DPY19L2, PICK1 and SPATA16 in Italian Unrelated Globozoospermic Men
Life, 2021 This study aims to evaluate genetic contribution and sperm DNA fragmentation (SDF) in a cohort of 18 unrelated globozoospermic Italian men (Group G). Semen samples were assessed according to the WHO 2010 Laboratory Manual and compared with 31 fertile ...
Fabiana Faja +7 more
doaj +1 more source
Rheotaxis facilitates upstream navigation of mammalian sperm cells [PDF]
, 2014 A major puzzle in biology is how mammalian sperm maintain the correct swimming direction during various phases of the sexual reproduction process. Whilst chemotaxis may dominate near the ovum, it is unclear which cues guide spermatozoa on their long ...
Dunkel, Jörn +8 more
core +1 more source
Reproductive Biology and Endocrinology, 2022 Background Previous research has shown that the type and duration of erotic material that men have access to during masturbation can influence semen parameters.
Daniel Rosenkjær +3 more
doaj +1 more source
Biomedicines, 2022 Virilization of gender-incongruent subjects to whom were assigned the female gender at birth (AFAB) is achieved through testosterone administration. Inter-individual differences in the timing and acquisition of phenotypic characteristics, even if the ...
Francesco Pallotti +12 more
doaj +1 more source