[1] Lanzhou Univ, Hosp 2, Dept Gen Surg, Lanzhou 730030, Peoples R China
[2] Lanzhou Univ, Hosp 2, Hepatobiliarypancreat Inst, Lanzhou 730030, Peoples R China
[3] Gansu Prov Level Key Lab Digest Syst Tumors, Lanzhou 730030, Peoples R China
[4] Lanzhou Univ, Div Liver Dis, Hosp 2, Lanzhou 730030, Peoples R China