Funding for this research was provided by:
2016 Henan Medical Education Project (Wjlx2016070)
Text and Data Mining valid from 2018-08-02
Received: 1 June 2018
Accepted: 27 July 2018
First Online: 2 August 2018
Ethics approval and consent to participate
: The study was evaluated by the Institutional Review Board of the First affiliated Hospital of Xinxiang Medical University. Informed consent was waived by the Institutional Review Board.
: Not applicable.
: The authors declare that they have no competing interests.
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