Funding for this research was provided by:
National Natural Science Foundation of China (81701942)
Fujian Provincial Health and Family Planning Commission Youth Research Project (2017-2-2)
Article History
Received: 8 October 2017
Accepted: 28 October 2018
First Online: 5 November 2018
Ethics approval and consent to participate
: The study protocol was approved by the Institutional Review Board of Fujian Provincial Hospital.
: Not applicable.
: The authors declare that they have no competing interests.
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