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Article History

Received: 10 June 2018

Accepted: 14 November 2018

First Online: 29 November 2018

Ethics approval and consent to participate

: Written informed consent for participation in the study was obtained from participants. Full approval from local Ethics Committee (KE 2016–001-2) of the Third Affiliated Hospital of Hebei Medical University.

: The authors declare that they have no competing interests.

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