[1] Lanzhou Univ, Dept Clin Med, Clin Med Coll 1, Lanzhou, Gansu, Peoples R China
[2] Gansu Prov Hosp, Dept Gen Surg, Lanzhou, Gansu, Peoples R China
[3] Lanzhou Univ, Sch Basic Med Sci, Evidence Based Med Ctr, Lanzhou, Gansu, Peoples R China
[4] Gansu Prov Hosp, Key Lab Mol Diagnost & Precis Med Surg Oncol, Lanzhou, Gansu, Peoples R China