1. Department of General Surgery, Shandong Cancer Hospital Affiliated to Shandong University, Shandong Academy of Medical Sciences, Jinan, Shandong 250117, P.R.�China
2. Department of Infectious Diseases, Capital Medical University Affiliated Beijing�You An Hospital, Beijing Institute of Hepatology, Beijing�100069, P.R.�China
3. Department of General Surgery, Changping District Hospital, Capital Medical University, Beijing�102200, P.R.�China
4. Department of Infectious Diseases, Capital Medical University Affiliated Beijing You An Hospital, Beijing Institute of Hepatology, Beijing 100069, P.R. China
5. Department of General Surgery, Shandong Cancer Hospital Affiliated to Shandong University, Shandong Academy of Medical Sciences, Jinan, Shandong 250117, P.R. China