Liu, F
Yang, X
Mo, X
Huang, J
Chen, J
Kelly, T N
Hixson, J E
Rao, D C
Gu, C C
Shimmin, L C
Chen, J
Rice, T K
Li, J
Schwander, K
He, J
Liu, D-p
Gu, D
Article History
Received: 18 March 2014
Revised: 25 June 2014
Accepted: 18 July 2014
First Online: 18 September 2014
Competing interests
: The authors declare no conflict of interest.