Funding for this research was provided by:
National Nature Science Foundation of China (81102145, 81573163)
Article History
Received: 2 May 2017
Accepted: 16 January 2018
First Online: 1 February 2018
Ethics approval and consent to participate
: The study was approved by the Biomedicine Ethical Committee of Anhui Medical University. The participants were fully informed of the purpose of the study and were invited to participate voluntarily. Written informed consent was obtained from the school, each participating student and either of the student’s parents.
: Not applicable.
: The authors declare that they have no competing interests.
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