1. Institute of Hepatobiliary Surgery, Chinese PLA General Hospital, Chinese PLA Medical School, Beijing 100853, P.R. China
2. Former Outpatient Department for Bureau of Information Communication, Agency for Offices Administration, Central Military Commission, Beijing 100840, P.R. China
3. Center for Hepatopancreatobiliary Diseases, Beijing Tsinghua Changgung Hospital, Tsinghua University, Beijing 102218, P.R. China