1. Department of Surgery, Hanchuan Renmin Hospital, Hanchuan, Hubei 431600, P.R. China
2. Department of Gastrointestinal Surgery, The Second People's Hospital of Shenzhen, Shenzhen, Guangdong 518037, P.R. China
3. Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
4. Shenzhen USK Bioscience Co., Ltd., Shenzhen, Guangdong 518110, P.R. China