1. Department of Gastroenterology, Haining Branch, The First Affiliated Hospital, Zhejiang University School of Medicine, Haining, Zhejiang 314400, China
2. Department of Gastroenterology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310003, China
3. Department of Gastroenterology, Haining People's Hospital, Haining, Zhejiang 314400, China
4. Zhejiang Provincial Clinical Research Center for Digestive Diseases, Hangzhou, Zhejiang 310003, China.