Funding for this research was provided by:
Teaching and Research Section of Shanghai Municipal Education Commission (JX09JC03201601)
Article History
First Online: 18 December 2017
Compliance with Ethical Standards
:
: Authors declare that they have 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 individual participants included in the study.