Xiaoze Wang1, Xuefeng Luo2, Li Yang2. 1. Department of Gastroenterology and Hepatology, West China Hospital, Sichuan University, 37 Guoxue Lane, Chengdu, 610041, Sichuan, People's Republic of China. xiaoze.wang@foxmail.com. 2. Department of Gastroenterology and Hepatology, West China Hospital, Sichuan University, 37 Guoxue Lane, Chengdu, 610041, Sichuan, People's Republic of China.