Irradiation interrupts spermatogenesis and causes prolonged sterility in male mammals. Hormonal suppression treatment with gonadotropin-releasing hormone (GnRH) analogues has restored spermatogenesis in irradiated rats, but similar attempts were unsuccessful in irradiated mice, monkeys, and humans. In this study, we tested a stronger hormonal suppression regimen (the GnRH antagonist, acyline, a...

This book is volume 2 in a series intended to introduce methods used in the study of protein biosynthesis. The present volume includes chapters on the genetic approach to the study of protein biosynthesis in plant systems, analysis of polysomes, fractionation of ribosomal proteins, animal operative techniques, and the use of sources of high energy phosphate. Inevitably, there is overlap with st...

The availability of the human genomic sequence is changing the way in which biological questions are addressed. Based on the prediction of genes from nucleotide sequences, homologies among their encoded amino acids can be analyzed and used to place them in distinct families. This serves as a first step in building hypotheses for testing the structural and functional properties of previously unc...

To summarize the maintenance of homeostasis in our body terms signal transduction, there are two major axes: autonomic nervous system and hormones. The system, one peripheral nerves, secretes neurotransmitters such as norepinephrine acetylcholine to affect target organs quickly efficiently. Hormones can be viewed signals that trigger larger changes DNA level after they secreted into blood reach...

different contraceptive methods are used by breastfeeding mothers. to investigate the effects of progestogen - only contraceptives on human milk components, a non-randomized, follow-up study was carried out in iran (varamin) on 140 breastfeeding women, 51 of whom used progestogenonly contraception including progestogen-only pills (pop) or depo-medroxyprogesterone acetate (dmpa), and 89 used non...

Recent studies identified the presence of a male polycystic ovarian syndrome (PCOS), which mainly affects men whose female relatives are afflicted with PCOS, caused by genes responsible for the susceptibility of this syndrome in women. Similar hormonal, metabolic, and clinical alterations occurring in PCOS women have also been reported in their male relatives, suggesting a association between t...

The aim of hormonal male contraception is to prevent unintended pregnancies by suppressing spermatogenesis. Hormonal male contraception is based on the principle that exogenous administration of androgens and other hormones such as progestins suppress circulating gonadotropin concentrations, decreasing testicular Leydig cell and Sertoli cell activity and spermatogenesis. In order to achieve mor...