1. Department of Emergency Surgery, The Affiliated Hospital of Qingdao University, 16 Jiangsu Road, Qingdao 266000, China
2. Department of General Surgery, The Affiliated General Hospital of Nanjing Military Region, 305 Zhongshan East Road, Nanjing 210016, China
3. Special Medicine Department, Medical College, Qingdao University, Qingdao 266071, China