1. Department of Pathology, Affiliated Hospital of North Sichuan Medical College, Nanchong, Sichuan 637000, P.R. China
2. Department of Pathology, The Third People's Hospital of Mianyang, Mianyang, Sichuan 621000, P.R. China
3. Department of Laboratory Medicine, Nanchong Central Hospital, Nanchong, Sichuan 637000, P.R. China