Wang, Xi-xing
Shuai, Wei
Hong, Kui
Xu, Jinsong
Li, Ju-xiang
Li, Ping
Cheng, Xiao-shu
Su, Hai
Article History
Received: 12 November 2015
Revised: 14 February 2016
Accepted: 15 February 2016
First Online: 31 March 2016
Competing interests
: The authors declare no conflict of interest.
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