Gu, Chunsun
Zhang, Xiaoxue
Jiang, Jiafu
Guan, Zhiyong
Zhao, Shuang
Fang, Weimin
Liao, Yuan
Chen, Sumei
Chen, Fadi
Article History
Received: 6 March 2014
Accepted: 7 July 2014
First Online: 25 July 2014
Competing interests
: The authors declare no competing financial interests.