1. Department of Gastroenterology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing 400042, China
2. Department of Gastroenterology, The 42 Hospital of People’s Liberation Army, Sichuan 614199, China
3. Department of Hepatobiliary Surgery, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing 400042, China