Bai, Danna
Zhang, Yajun
Shen, Mingzhi
Sun, Yongfeng
Xia, Qing
Zhang, Yingmei
Liu, Xuedong
Wang, Haichang
Yuan, Lijun
Article History
Received: 19 August 2015
Accepted: 5 February 2016
First Online: 24 February 2016
Competing interests
: The authors declare no competing financial interests.