1. Department of Orthopedics, Sports Medicine Center, People’s Liberation Army General Hospital, No. 28 Fu Xing Road, Haidian District, Beijing 100853, P.R. China
2. Department of Cell Biology, Institute of Basic Medical Sciences, No. 27 Tai Ping Road, Haidian District, Beijing 100850, P.R. China
3. Department of Hematology, General Hospital of Air Forces, PLA, No. 30 Fu Cheng Road, Haidian District, Beijing 100142, P.R. China