Funding for this research was provided by:
National Natural Science Foundation of China (81571856)
Received: 29 December 2019
Accepted: 15 July 2020
First Online: 31 July 2020
Ethics approval and consent to participate
: Written informed consent was obtained from all the study participants. All participants read the informed consent, and we explained the relevant contents of the informed consent to them. Then all participants signed to agree to the relevant contents. This study protocol was approved by the Ethical Committee of the Medical College, Xi’an Jiaotong University.
: Not applicable.
: The authors declare that they have no competing interests.