1. Department of Gastroenterology, Affiliated Hospital 1, Xi`an Jiaotong University, Xian, China
2. Department of Gastroenterology, Changhai Hospital, Second Military Medical University, Shanghai, China
3. Taishan Medical University, Taian, China
4. Department of Hepatobiliary Surgery, Second Hospital of Jiaxing, Jiaxing, China
5. No. 411 Hospital of PLA, Shanghai, China