Funding for this research was provided by:
National Natural Science Foundation of China (31400865)
Article History
Received: 17 April 2017
Accepted: 2 January 2018
First Online: 9 January 2018
Compliance with ethical standards
:
: All procedures performed in present studies involving human participants were in accordance with the ethical standards of the institutional and national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.
: All participants gave their informed consent prior to their inclusion in the study.
: The authors declare that they have no conflict of interest.