Funding for this research was provided by:
National Natural Science Foundation of China (81370574, 81670591)
Natural Science Foundation of Guangdong Province (2016A030311028)
Science and Technology Program of Guangzhou, China (201704020073)
Text and Data Mining valid from 2019-03-07
Received: 4 April 2018
Accepted: 19 February 2019
First Online: 7 March 2019
Ethics approval and consent to participate
: Not applicable. All analyses were based on previous published studies,thus no ethical approval and patient consent are required.
: Not applicable.
: The authors declare that they have no competing interests.
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