[1] North Sichuan Med Coll, Affiliated Hosp, Dept Gen Surg, Nanchong 637000, Peoples R China
[2] North Sichuan Med Coll, Inst Hepatobiliary Pancreat Intestinal Dis, Nanchong 637000, Peoples R China
[3] North Sichuan Med Coll, Chengdu XinHua Hosp, Chengdu 610000, Peoples R China
[4] Nanchong Psychosomat Hosp, Nanchong 637770, Peoples R China