1. Department of Gastroenterology, Renmin Hospital of Wuhan University, Wuhan, Hubei Province, China
2. Department of Gastroenterology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu Province, China
3. Key Laboratory of Hubei Province for Digestive System Disease, Renmin Hospital of Wuhan University, Wuhan, Hubei Province, China