Funding for this research was provided by:
National Natural Science Foundation of China (71573118)
Text and Data Mining valid from 2020-05-06
Received: 8 July 2019
Accepted: 27 April 2020
First Online: 6 May 2020
Ethics approval and consent to participate
: Ethical approval was obtained from the Medical Faculty Ethics Committee of Nanjing Medical University (file number 316) and written informed consent from every participant was obtained before the investigation.
: No applicable.
: The authors declare that they have no competing interests.