title: Letter: The brass-ring sign.
mesh_terms: D000328:Adult; D001714:Bipolar Disorder / Q000503:physiopathology; D003920:Diabetes Mellitus / Q000503:physiopathology; D005260:Female; D006801:Humans; D011293:Premenstrual Syndrome / Q000503:physiopathology; D012877:Skin Manifestations; D013542:Sweat / Q000032:analysis* / Q000378:metabolism