Pan, Yingfang
Wang, Bo
Yang, Xiaoyun
Bai, Fuxiang
Xu, Qun
Li, Xueen
Gao, Lifen
Ma, Chunhong
Liang, Xiaohong
Article History
Received: 4 February 2015
Accepted: 22 October 2015
First Online: 23 November 2015
Competing interests
: The authors declare no competing financial interests.