Yang, Yan
Zhu, Li-min
Xu, Jian-zhong
Tang, Xiao-feng
Gao, Ping-jin
Article History
Received: 17 December 2015
Revised: 13 July 2016
Accepted: 8 August 2016
First Online: 13 October 2016
Competing interests
: The authors declare no conflict of interest.
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