Funding for this research was provided by:
National Natural Science Foundation of China (81673155)
Text and Data Mining valid from 2019-10-11
Received: 19 July 2019
Accepted: 26 September 2019
First Online: 11 October 2019
Ethics approval and consent to participate
: This study was approved by the ethics committee of the Third Military Medical University.
: The authors consent to the publication of the data.
: The authors declare they have no competing interests.