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Article History

Received: 23 August 2018

Accepted: 21 November 2018

First Online: 6 December 2018

Ethics approval and consent to participate

: This study was reviewed and approved by the institutional Review Board of the First Affiliated Hospital of Nanjing Medical University. The need for patient consent was waived by the same ethics committee.

: Not applicable.

: The authors declare that they have no competing interests.

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