1. Department of Neurosurgery, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengdu 610041, P.R. China
2. State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Chengdu 610041, P.R. China
3. Department of Stomatology, Daping Hospital, Third Military Medical University, Chongqing 400042, P.R. China
4. Key Laboratory of Wound Repair and Regeneration of PLA, Chinese PLA General Hospital, Medical College of PLA, Beijing 100853, P.R. China