Funding for this research was provided by:
Science and Technology Project of Guangzhou (201604020093)
Medical scientific research project of Guangdong Province (A2017082)
Text and Data Mining valid from 2018-05-01
Received: 22 November 2017
Accepted: 20 April 2018
First Online: 1 May 2018
Ethics approval and consent to participate
: Not applicable.
: The authors declare that they have no competing interests.
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