Funding for this research was provided by:
Taishan Scholar Foundation of Shandong Province
Article History
Received: 3 September 2018
Accepted: 30 October 2018
First Online: 15 November 2018
Compliance with Ethical Standards
:
: Deyun He declares that she has no conflict of interest. Zhengzong Wu declares that he has no conflict of interest. Bo Cui declares that he has no conflict of interest. Enbo Xu declares that he has no conflict of interest. Zhengyu Jin declares that he has no conflict of interest.
: This article does not contain any studies with human or animal subjects.
: Informed consent was obtained from all individual participants included in the study.