The biology of ageing. 2. Reduced resistance.
D000368:Aged; D000375:Aging; D001327:Autoimmune Diseases / Q000276:immunology; D005260:Female; D006680:HLA Antigens; D006801:Humans; D007109:Immunity; D008297:Male; D008875:Middle Aged; D012141:Respiratory Tract Infections / Q000276:immunology
D006680:HLA Antigens