Xiang, Ying
Wang, Zhigang
Bian, Jingxia
Xu, Yunlan
Fu, Qihua
Article History
Received: 10 October 2015
Revised: 10 May 2016
Accepted: 23 May 2016
First Online: 16 June 2016
Competing interests
: The authors declare no conflict of interest.
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