Funding for this research was provided by:
Natural Science Foundation of Guangdong Province (2015A030313180)
Article History
Received: 15 March 2019
Accepted: 8 June 2019
First Online: 13 June 2019
Compliance with ethical standards
:
: All the authors declare that they have no competing conflict of interest.
: All procedures performed in research involving human participants were in accordance with the ethical standards of the institutional research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.