1. Department of Liver and Gallbladder Surgery, The Second Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang 712000, Shaanxi, China
2. Department of Liver and Gallbladder Surgery, Baoji People’s Hospital, Baoji 716000, Shaanxi, China
3. Department of General Surgery, Affiliated Hospital of Yan’an University, Yan’an 721000, Shaanxi, China