Funding for this research was provided by:
National Natural Science Foundation of China (81673800)
Text and Data Mining valid from 2019-11-05
Received: 6 June 2019
Accepted: 23 October 2019
First Online: 5 November 2019
Ethics approval and consent to participate
: Not applicable since the experiments in this study did not involve human participants.
: Not applicable.
: The authors declare that they have no conflicts of interest.