Funding for this research was provided by:
Hainan provincial health fund (02A2150014P1)
Text and Data Mining valid from 2018-08-29
Received: 23 June 2018
Accepted: 13 August 2018
First Online: 29 August 2018
Ethics approval and consent to participate
: The present study was authorized by the Ethics Committee of Hainan General Hospital. All procedures performed in studies were in accordance with the ethical standards. All patients and volunteers were anonymous and have provided written informed consent.
: Not applicable.
: The authors declare that they have no competing interests.
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