Fang, Nan
Yang, Huiying
Fang, Haihong
Liu, Lei
Zhang, Yiquan
Wang, Li
Han, Yanping
Zhou, Dongsheng
Yang, Ruifu
Article History
Received: 7 July 2014
Accepted: 11 March 2015
First Online: 1 April 2015
Competing interests
: The authors declare no competing financial interests.