Liu, Shuang-he
Xu, Mei-dong
Zhang, Hui
Qi, Huan
Zhang, Ji
Liu, Chong-xi
Wang, Ji-dong
Xiang, Wen-sheng
Wang, Xiang-jing
Article History
Received: 17 June 2015
Revised: 24 August 2015
Accepted: 25 August 2015
First Online: 16 September 2015
Competing interests
: The authors declare no conflict of interest.
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