[Different gain-setting affects measurement of extrahepatic bile duct by real-time ultrasound].
D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D003135:Common Bile Duct / Q000033:anatomy & histology* / Q000473:pathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D014463:Ultrasonography / Q000379:methods*