Funding for this research was provided by:
National Natural Science Foundation of China (31771486)
Text and Data Mining valid from 2020-02-03
Received: 18 October 2019
Accepted: 20 January 2020
First Online: 3 February 2020
Ethics Approval and Consent to Participate
: Note applicable.
: The manuscript has been read and approved by all authors.
: The authors declare that they have no competing interests.