1. Department of Spinal Surgery, Peking University People's Hospital, Peking University, Beijing, P.R. China.
2. Beijing National Laboratory for Molecular Sciences, Key Laboratory of Molecular Nanostructure and Nanotechnology, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, P.R. China.
3. Department of Spinal Surgery, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, P.R. China.