1. State Key Laboratory of Cancer Biology, National Clinical Research Center for Digestive Diseases, Xijing Hospital of Digestive Diseases, Fourth Military Medical University, Xi’an, Shaanxi 710032, China
2. Department of Emergency, Xin’an Central Hospital, Xi’an, Shaanxi 710048, China
3. Department of Gastroenterology, Xi’an No.1 Hospital, Xi’an, Shaanxi 710002, China.