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Article History

Received: 8 February 2020

Accepted: 11 January 2021

First Online: 18 January 2021

Compliance with ethical standards

:

: The authors declare that they have no conflict of interest.

: The study was approved by the Human Research Ethics Committee of Peking Union Medical College Hospital. All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.

: Informed consent was obtained from all subjects in the study.

: All authors consent to the publication of the manuscript.

: Not applicable.