title: Seasonal changes in plasma androgen levels and the gonads of the beach vole, Microtus breweri.
mesh_terms: D000728:Androgens / Q000097:blood*; D000818:Animals; D003411:Arvicolinae / Q000502:physiology*; D001683:Biological Clocks; D001835:Body Weight; D006651:Histocytochemistry; D007986:Luteinizing Hormone / Q000494:pharmacology; D008297:Male; D009929:Organ Size; D012098:Reproduction; D012377:Rodentia / Q000502:physiology*; D012621:Seasons; D013091:Spermatogenesis; D013737:Testis / Q000033:anatomy & histology / Q000502:physiology
chemical_list: D000728:Androgens; D007986:Luteinizing Hormone