Funding for this research was provided by:
National Natural Science Foundation of China (81672182)
Text and Data Mining valid from 2020-01-22
Received: 10 July 2019
Accepted: 14 January 2020
First Online: 22 January 2020
Ethics approval and consent to participate
: The Ethics Committee of the Third Hospital of Peking University approved this study. (NO. 000067612014205). All subjects provided informed consent to take part in the study.
: Not applicable.
: The authors declare that they have no competing interests.