Received: 19 July 2018
Accepted: 3 December 2018
First Online: 14 January 2019
Ethics approval and consent to participate
: Ethical review committee statement: This prospective study has been approved by Ethics Committee of the First Affiliated Hospital of Chongqing Medical University and registered in Chinese Clinical Trial Registry (ChiCTR).
: The authors declare that they have no competing interests.
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