Hou, Qingtao
Li, Sheyu
Gao, Yun
Tian, Haoming
Article History
Received: 1 November 2017
Accepted: 24 April 2018
First Online: 10 May 2018
Ethics approval and consent to participate
: This study was conducted in accordance with the Declaration of Helsinki. All participants provided informed consent for participation in the study.
: The authors declare that they have no competing interests.
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