title: Non-incidental concomitancy of gastric and duodenal ulcers.
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D002648:Child; D002675:Child, Preschool; D004381:Duodenal Ulcer / Q000150:complications* / Q000453:epidemiology; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007564:Japan; D008297:Male; D008875:Middle Aged; D012737:Sex Factors; D013276:Stomach Ulcer / Q000150:complications* / Q000453:epidemiology