Funding for this research was provided by:
National Natural Science Foundation of China (81472931)
Text and Data Mining valid from 2018-05-29
Received: 15 December 2017
Accepted: 21 May 2018
First Online: 29 May 2018
Ethics approval and consent to participate
: The study was performed in accordance with the Declaration of Helsinki and approved by the Human Ethics Committee of Endemic Disease Center of Harbin Medical University, PR of China. Written informed consent was also obtained from the subjects.
: The authors declare that they have no competing interests.
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