Received: 10 November 2020
Accepted: 29 December 2020
First Online: 12 January 2021
Ethics approval and consent to participate
: All procedures performed in studies involving human participants were in accordance with the ethical standards of Shanxi Provincial People’s Hospital research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. All participants gave their informed consent in writing prior to inclusion in the study.
: Not applicable.
: The authors declare that they have no competing interests.