Article History
Received: 20 September 2020
Accepted: 14 February 2021
First Online: 23 February 2021
Ethics approval and consent to participate
: All procedures performed in this study was approved by the relevant institutional review board (Ethics Committee of Peking University Health Science Center, PKUSSIRB-201417105), and was in accordance with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. For this type of study, formal consent is not required.
: Not applicable.
: The authors declare no competing interests related to the authorship and/or publication of this article.