Article History
Received: 7 November 2017
Accepted: 5 January 2018
First Online: 15 January 2018
Ethics approval and consent to participate
: The study was approved by the Ethics Committee of Chao-yang hospital Ethics committee, Capital Medical University. Consent to participate was obtained from participant.
: Consent to publish from the participant.
: The authors declare that they have no competing interests.
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