[Muscle biopsy in polymyositis; report of 20 cases].
D000293:Adolescent; D000328:Adult; D001706:Biopsy; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009132:Muscles / Q000473:pathology*; D009220:Myositis / Q000473:pathology*