1. Department of General Surgery, Institute of General Surgery, Northern Jiangsu Provincial People's Hospital, Clinical Medical College, Yangzhou University, Yangzhou, Jiangsu 225001, P.R. China
2. Department of Clinical Medicine, Medical College of Yangzhou University, Yangzhou, Jiangsu 225001, P.R. China
3. Department of General Surgery, Anhui Second Provincial People's Hospital, Hefei, Anhui 230000, P.R. China
4. Department of General Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China