Funding for this research was provided by:
National Natural Science Foundation of China (No.81760234)
Text and Data Mining valid from 2020-03-04
Received: 11 March 2019
Accepted: 23 January 2020
First Online: 4 March 2020
Ethics approval and consent to participate
: All participants were voluntary and provided written informed consent before taking part in this research. This study was approved by the Research Ethics Committee of Haikou People’s Hospital, and in compliance with the Declaration of Helsinki. The design and performance of this study involving human subjects were obviously described in a research protocol.
: Not applicable.
: The authors declare that they have no competing interest.