Received: 9 November 2018
Accepted: 31 March 2021
First Online: 13 April 2021
: This research was performed in accordance with the Declaration of Helsinki and approved by the Ethical Committee of Chongqing Medical University (ethical approval code: 2016001). All participants were informed of the purpose of the study and their cooperation was voluntary, and they submitted signed informed consent.
: Not applicable
: The authors declare no conflict of interests.