Funding for this research was provided by:
Science and Technology Plan Foundation of Guangdong (2017B010119002)
Science and Technology Plan Foundation of Guangzhou (201704030031, 201803030015)
Text and Data Mining valid from 2019-03-15
Received: 18 October 2018
Accepted: 5 March 2019
First Online: 15 March 2019
Ethics Approval and Consent to Participate
: Not applicable.
: The authors declare that they have no competing interests.
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