Letter: Peptic ulcer in childhood.
D002648:Child; D004381:Duodenal Ulcer / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D010437:Peptic Ulcer / Q000453:epidemiology*; D012042:Registries; D013276:Stomach Ulcer / Q000453:epidemiology; D014481:United States