Qi, Bing
Cong, Qian
Li, Ping
Ma, Gang
Guo, Xizhi
Yeh, James
Xie, Min
Schneider, Michael D.
Liu, Huijuan
Li, Baojie
Article History
Received: 7 July 2014
Accepted: 21 October 2014
First Online: 24 November 2014
Competing interests
: The authors declare no competing financial interests.