title: Age-specific diagnostic values of the blood urea nitrogen/creatinine ratio in distinguishing upper from lower gastrointestinal bleeding.
authors.affiliation: Department of Internal Medicine, Teikyo University, School of Medicine, Tokyo, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Sanaka
authors.forename: Y
authors.initials: Y
authors.lastname: Kuyama
authors.forename: S
authors.initials: S
authors.lastname: Nishinakagawa
authors.forename: M
authors.initials: M
authors.lastname: Yamanaka
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001806:Blood Urea Nitrogen; D019411:Clinical Laboratory Techniques; D003401:Creatine / Q000097:blood*; D003937:Diagnosis, Differential; D004378:Duodenal Diseases / Q000097:blood / Q000175:diagnosis; D006471:Gastrointestinal Hemorrhage / Q000097:blood / Q000175:diagnosis*; D006801:Humans; D007410:Intestinal Diseases / Q000097:blood / Q000175:diagnosis*; D008875:Middle Aged; D012680:Sensitivity and Specificity; D013272:Stomach Diseases / Q000097:blood / Q000175:diagnosis*
chemical_list: D003401:Creatine