Funding for this research was provided by:
This study was supported partly by the Hainan Provincial Medical and Health Research Projects. (1421320.24A1005)
Received: 19 February 2018
Accepted: 3 May 2018
First Online: 1 June 2018
Ethics approval and consent to participate
: This study was approved by the Ethical Committee, the Third People′s Hospital of Hainan Province. All participants provided written informed consent.
: Participants were informed of data sharing with their name and identity hidden per consent.
: The authors declare that they have no competing interests.
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