Funding for this research was provided by:
The Education department Project in Zhejiang Province (No.Y201636869)
Article History
Received: 29 November 2017
Accepted: 29 June 2018
First Online: 13 July 2018
Ethics approval and consent to participate
: This prospective study was approved by the Institutional Medical Ethics Committee and adhered to the tenets of the Declaration of Helsinki. Informed written consent was obtained from all the participants and their parents.
: Consent was obtained from the participant (and legal parent or guardian for children) to publish and report individual patient data.
: The authors declare that they have no competing interests.
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