Article History
Received: 12 March 2019
Accepted: 22 May 2019
First Online: 3 July 2019
Compliance with ethical standards
:
: Author Yong Tang, Author Guojun Cao, Author Gang Zhao,Author Chunyou Wang as well as Author Qi Qin all declare that they have no competing interests.
: All procedures performed in studies 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.
: Informed consent was obtained from all individual participants included in the study.