Funding for this research was provided by:
Science and Technology Planning Projects of Guangdong Province (2016B030307003, 2017B020210001)
Training Program of the Major Research Plan of Sun Yat-Sen University (17ykjc10)
Text and Data Mining valid from 2019-04-08
Received: 17 November 2018
Accepted: 31 March 2019
First Online: 8 April 2019
Ethics approval and consent to participate
: The current study was approved by the Institutional Ethics Committee of the First Affiliated Hospital of Sun Yat-Sen University, and the need for signed informed consent was waived.
: Not applicable.
: The authors declare that they have no competing interests.
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