Guangdong Provincial Key Laboratory of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou 510515, Guangdong Province, China
Department of Epidemiology, School of Public Health and Tropical Medicine, Southern Medical University,Guangzhou 510515, Guangdong Province, China
Department of Gastroenterol ogy, Nanfang Hospital, Southern Medical University, Guangzhou 510515, Guangdong Province, China