1. University of Electronic Science and Technology of China,School of Computer Science and Engineering,Chengdu,China,611731
2. University of Electronic Science and Technology of China,School of Information and Software Engineering,Chengdu,China,610054
3. Sichuan University,West China School of Medicine,Chengdu,China,610065
4. Fourth Military Medical University,Xijing Orthopaedics Hospital,Xi’an,P. R. China,710032