[Epidemiological surveys of asymptomatic gallstones].
D000328:Adult; D000367:Age Factors; D000368:Aged; D002769:Cholelithiasis / Q000175:diagnosis / Q000453:epidemiology*; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D012737:Sex Factors; D014463:Ultrasonography