1. Department of Pathology, School of Basic Medicine, Ningxia Medical University, Yinchuan, Ningxia 750004, P.R. China
2. Department of Pathology, Tumor Hospital, General Hospital of Ningxia Medical University, Yinchuan, Ningxia 750004, P.R. China
3. Functional Department, Ningxia Hui Autonomous Region People's Hospital, Yinchuan, Ningxia 750021, P.R. China
4. Department of Pathology, The First People's Hospital of Yinchuan, Yinchuan, Ningxia 750001, P.R. China