1. Department of General Surgery, Jinling Hospital, Medical School of Nanjing University, No. 305 East Zhongshan Road, Nanjing, China
2. Department of General Surgery, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, No. 321 Zhongshan Road, 210008 Nanjing, Jiangsu, China
3. Department of Gastrointestinal Surgery, The Affiliated Hospital of Qingdao University, Qingdao, Shandong Province, China