Funding for this research was provided by:
National Natural Science Foundation of China (U160310041, 3177110697)
Text and Data Mining valid from 2019-06-24
Received: 21 February 2019
Accepted: 31 May 2019
First Online: 24 June 2019
Ethics approval and consent to participate
: This article does not contain any studies with human participants or animals performed by any of the authors.
: Not applicable.
: The authors declare that they have no competing interests.