Funding for this research was provided by:
National Natural Science Foundation of China (71403177)
Received: 4 November 2019
Accepted: 25 June 2020
First Online: 2 July 2020
Ethics approval and consent to participate
: This study was approved by the medical ethics review board of Capital Medical University, China, and all the participants signed a consent form. We explained the contents of the experiment to all participants and signed an informed consent form with them.
: Not applicable.
: The authors declare that they have no competing interests.