Fei Liu1, YongGang Wei2, Bo Li3. 1. Department of Liver Surgery and Liver Transplantation Center, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China. 2. Department of Liver Surgery and Liver Transplantation Center, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China. hxwyg@scu.edu.cn. 3. Department of Liver Surgery and Liver Transplantation Center, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China. cdlibo688@163.com.