Funding for this research was provided by:
Natural Science Foundation of Hunan Province (2017JJ3215)
Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University (GMU-2017-005)
Text and Data Mining valid from 2018-05-29
Received: 21 January 2018
Accepted: 17 May 2018
First Online: 29 May 2018
: The authors declare that they have no competing interests.
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