Yu Li1,2,3, Nan Zhang2,3, Yi Lv1,2,3. 1. Department of Hepatobiliary Surgery, the First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China. 2. National Local Joint Engineering Research Center for Precision Surgery & Regenerative Medicine, Xi'an, China. 3. Shaanxi Province Center for Regenerative Medicine and Surgery Engineering Research, Xi'an, China.