Yuan, Xiao-Yan
Yu, Dong-Ying
Qu, Xue-Hong
Xiao, Xin-Qiang
Bi, Bo
Sun, Sheng-Bo
Chang, Ai-Ying
Zhang, Qi-bo
Article History
Received: 21 December 2014
Revised: 1 September 2015
Accepted: 4 September 2015
First Online: 30 September 2015
Competing interests
: The authors declare no conflict of interest.
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