Department of General Surgery;
Sun Yat-Sen Memorial Hospital;
Sun Yat-Sen University;
Guangzhou 510120;
Guangdong Province;
China;
Department of General Surgery;
West China Hospital;
Sichuan University;
Chengdu 610041;
Sichuan Province;
China;
Department of General Surgery;
Gansu Provincial Hospital;
Lanzhou 730000;
Gansu Province;
China;