title: Free triiodothyronine (t3)- and thyroxine (t4) serum levels in old age.
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging; D006801:Humans; D008875:Middle Aged; D013974:Thyroxine / Q000097:blood* / Q000378:metabolism; D014284:Triiodothyronine / Q000097:blood* / Q000378:metabolism
chemical_list: D014284:Triiodothyronine; D013974:Thyroxine