Funding for this research was provided by:
National Natural Science Foundation of China (81772277)
Text and Data Mining valid from 2019-11-06
Received: 5 September 2019
Accepted: 23 October 2019
First Online: 6 November 2019
Ethics approval and consent to participate
: The study has been examined and certified by the Ethics Committee of the First Affiliated Hospital of Dalian Medical University (Ethics Reference NO: YJKY-FB-2016-16), and informed consent was obtained from all participants included in the study, in agreement with institutional guidelines.
: Not applicable.
: The authors declare that they have no competing interests.