Funding for this research was provided by:
National Natural Science Foundation of China (No.81402732)
Wuxi project of Science and Technology (No.CSE31N1515)
Jiangsu Project of Preventive Medicine (No. Y2015006)
Wuxi Project of Key Medical Disciplines (No. ZDRC003)
Wuxi Project of Young Medical Talents (No. QNRC008)
Text and Data Mining valid from 2018-09-19
Received: 2 February 2018
Accepted: 14 September 2018
First Online: 19 September 2018
Ethics approval and consent to participate
: This investigation was conducted by public health agencies as part of their legally authorised mandate and was therefore considered minimal-risk research and was exempted from ethical approval by the Institutional Review Board-Wuxi Center for Disease Control and Prevention.
: Not applicable.
: The authors declare that they have no competing interests.
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