1. Department of Physiology, Ningxia Medical University, Yinchuan, Ningxia 750004, P.R. China
2. General Hospital of Ningxia Medical University, Yinchuan, Ningxia 750004, P.R. China
3. Ningxia Key Laboratory of Cerebrocranial Diseases, Incubation Base of National Key Laboratory, Ningxia Medical University, Yinchuan, Ningxia 750004, P.R. China