1. Translational Medicine Research Center, Fourth Medical Center and Medical Innovation Research Division of the Chinese PLA General Hospital, Beijing 100048, P.R. China
2. Department of Ultrasound, Community Health Service Center, Changping, Beijing 100096, P.R. China
3. Faculty of Hepato-Pancreato-Biliary Surgery, Chinese PLA General Hospital, Beijing 100853, P.R. China
4. Department of Pathology, Fourth Medical Center of The Chinese PLA General Hospital, Beijing 100048, P.R. China