Funding for this research was provided by:
Chongqing Scientific Innovation Project for Postgraduates (CYB17064)
Chongqing Science and Technology Committee (cstc2018jscx-mszd0133, cstc2017shms-xdny80084)
Zunyi Tobacco Company (ZY 2015-03, ZY 2018-01)
Article History
Received: 28 January 2019
Accepted: 14 June 2019
First Online: 4 July 2019
Compliance with ethical standards
:
: The authors declare that they have no conflict of interest.
: There is no research involving Human Participants and/or Animals in this article.
: Informed consent was obtained from all individual participants included in the study.