Funding for this research was provided by:
National Natural Science Foundation of China (81201388)
Text and Data Mining valid from 2018-06-06
Received: 29 November 2017
Accepted: 8 May 2018
First Online: 6 June 2018
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: Written informed consent for participation in the study was obtained from participants. This study was approved by the Institutional Ethical Board of the First Affiliated Hospital of Sun Yat-sen University.
: The authors declare that they have no competing interests.
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