نتایج جستجو برای: male fertility
تعداد نتایج: 364247 فیلتر نتایج به سال:
The male uro-genital tract is susceptible to gram-negative bacterial infections that produce a state of inflammation, particularly in the testis and epididymis. Development of germline stem cells into motile spermatozoa takes place in these organs and thus any impairment therein has a direct effect on male fertility. A number of factors are known to impair male fertility including environmental...
Fertility impairments among men treated during childhood for cancer are known to occur after some, but not all, types of anti-cancer therapy. This is the first study to evaluate proven fertility among adult male survivors of childhood acute lymphoblastic leukemia (ALL). In a retrospective cohort study, proven fertility (ever fathered a pregnancy) was evaluated by self-report among 213 men treat...
BACKGROUND Spermatogonial stem cells (SSCs) are the foundation of spermatogenesis and represent a crucial resource for male fertility restoration. It has not been well documented, however, whether the recovery of SSC population size after cytotoxic damage associates with the kinetics of male fertility restoration. We addressed this issue using the mouse as a model. METHODS Following single in...
background: the task force on plants for fertility regulation in men continued with its program to identify novel prototypes in plants alleged to have fertility regulating properties. nigella sativa objective: to evaluated the role of alcoholic extract of nigella sativa on fertility potential, pituitary-testicular axis hormones and testosterone in male rats. materials and methods: 24 male r...
Deficiency mapping with Y autosome translocations has shown that the Y chromosome of Drosophila melanogaster carries genes that are essential to male fertility. While the qualitative behavior of these lesions provides important insight into the physiological importance of the Y chromosome, quantitative variation in effects on male fertility among extant Y chromosomes in natural populations may ...
Sperm experience intense and varied selection that dramatically impacts the evolution of sperm quality. Selection acts to ensure that sperm are fertilization-competent and able to overcome the many challenges experienced on their way towards eggs. However, simply being able to fertilize an egg is not enough to ensure male fertility in most species. Owing to the prevalence of female multiple mat...
To study the evolutionary role played by differential male and female fertility (sexual asymmetry) both between individuals and over the life span within single individuals, the terms "intrinsic male fertility" and "intrinsic female fertility" are introduced. With the help of these terms, the concept of sexual asymmetry can be made precise and its effect on the establishment and maintenance of ...
Recent studies investigating possible causes of male subfertility have largely focused on how lifestyle or environmental factors impact on the process of spermatogenesis. Markedly, fewer studies have investigated those risk factors that result in reduced sperm quality, such as poor sperm motility. The speed at which sperm swim is a major predictor of fertility and is extremely variable in human...
Maintenance of normal male fertility relies on the process of spermatogenesis which is under complex endocrine control by mechanisms involving gonadotropin and steroid hormones. Although testosterone is the primary sex steroid in males, estrogen is locally produced in the testis and plays a very crucial role in male fertility. This is evident from presence of both the estrogen receptors alpha (...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید