Yan, Jing
Zhang, Jie
Zhang, Qian
Zhang, Xinlu
Ji, Kui
Article History
Received: 8 September 2017
Accepted: 8 January 2018
First Online: 27 January 2018
Compliance with ethical standards
:
: The 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.