TY - JOUR AN - 6 AU - Chu,K.M. AU - Kwok,K.F. AU - Law,S. TI - Patients with Helicobacter pylori positive and negative duodenal ulcers have distinct clinical characteristics. JO - World J Gastroenterol PY - 2005 VL - 11 SP - 3518-3522 M2 - 3518 ER -