title: Early gastrointestinal endoscopy in the diagnosis of acute upper gastrointestinal bleeding.
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D006471:Gastrointestinal Hemorrhage / Q000175:diagnosis*; D005773:Gastroscopy / Q000379:methods*; D006801:Humans; D008297:Male; D008875:Middle Aged