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Article History

Received: 28 May 2020

Accepted: 20 July 2020

First Online: 29 July 2020

Ethics approval and consent to participate

: This study was approved by the biomedical research ethics committee of Peking University First Hospital (approval No. 2018, scientific research 242), and the need for informed consent was waived.

: Not applicable.

: The authors declare that they have no competing interests.