1. The First Affiliated Hospital, Department of Hepato-Biliary-Pancreatic Surgery, Hengyang Medical School, University of South China, Hengyang City, Hunan Province, China
2. Department of Hepato-Biliary-Pancreatic Surgery, The First People's Hospital of Huaihua, Huaihua City, Hunan Province, China
3. The First Affiliated Hospital, Department of Gastroenterology and Hepatology, Hengyang Medical School, University of South China, Hengyang City, Hunan Province, China