Nan, Fan
Cheng, Zi-Qiang
Wang, Ya-Lan
Zhang, Qing
Zhou, Li
Yang, Zhong-Jian
Zhong, Yu-Ting
Liang, Shan
Xiong, Qihua
Wang, Qu-Quan
Article History
Received: 26 November 2013
Accepted: 2 April 2014
First Online: 2 May 2014
Competing interests
: The authors declare no competing financial interests.