Funding for this research was provided by:
Fundamental Research Funds for the Central Universities (SWU1809354)
Article History
First Online: 21 March 2019
Compliance with Ethical Standards
:
: All authors declare that there no conflict of interest.
: All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.
: Informed consent was obtained from all participants and their parents in the study.