Zhang, Jiaming
Zhang, Fanghua
Zhao, Changying
Xu, Qian
Liang, Cheng
Yang, Ying
Wang, Huiling
Shang, Yongfang
Wang, Ye
Mu, Xiaofeng
Zhu, Dequan
Zhang, Chunling
Yang, Junjie
Yao, Minxiu
Zhang, Lei http://orcid.org/0000-0003-4284-2604
Funding for this research was provided by:
the National Natural Science Foundation of China (31471202)
the National Natural Science Foundation of China (81670822)
the Shandong Provincial Key Research and Development Program (2016YYSP009)
Weihai Technique Extension Project (2016GNS023)
Qingdao Key Research Project (17-3-3-10-nsh)
the Taishan Scholars Program of Shandong Province (tshw20120206)
Article History
Received: 27 October 2018
Accepted: 12 December 2018
First Online: 24 December 2018
Compliance with ethical standards
:
: The authors declare that they have no conflict of interest. The authors have nothing to disclose.
: All procedures performed in the above studies involving human participants were in accordance with the ethical standards of the institution and/or national research committee and with the 1964 Declaration of Helsinki along with its later amendments or comparable ethical standards.
: All the subjects signed informed consent beforehand and belonged to the same geographical area. Data was collected by using a standardized questionnaire including basic information, medical history and examination results.