1. Department
of Periodontology, Stomatological Hospital, Jilin University, Changchun 130021, P. R. China
2. Department
of Human Anatomy, College of Basic Medical Sciences, Jilin University, Changchun 130021, P. R. China
3. State
Key laboratory of Rare Earth Resource utilization, Changchun Institute
of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, P. R. China