title: Decline in sexual activity in ageing men: correlation with sex hormone levels and testicular changes.
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging; D012739:Gonadal Steroid Hormones / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012725:Sexual Behavior; D013737:Testis / Q000166:cytology*
chemical_list: D012739:Gonadal Steroid Hormones