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Article History

Received: 26 December 2019

Accepted: 24 June 2020

First Online: 6 July 2020

Ethics approval and consent to participate

: This study was approved by the ethical committee of the Capital medical university, Beijing Anzhen hospital. Written informed consent was obtained from all participants.

: The subjects gave written informed consent for the publication of any associated data.

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