1. State Key Laboratory of Veterinary Etiological Biology and Office International des Epizooties/National Foot and Mouth Disease Reference Laboratory and Key Laboratory of Animal Virology of the Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu 730000, P.R. China
2. Department of Tumour and Anorectal, Second People's Hospital of Baiyin City, Baiyin, Gansu 730900, P.R. China
3. The Fourth Department of General Surgery, The First Hospital of Lanzhou University, Lanzhou, Gansu 730000, P.R. China
4. The First Clinical Medical School of Lanzhou University, Lanzhou University, Lanzhou, Gansu 730000, P.R. China