Cao, Muqing
Zhu, Yanna
Li, Xiuhong
Chen, Yajun
Ma, Jun
Jing, Jin
Funding for this research was provided by:
Students Major Disease Prevention & Control Technology and Its Development and Application (201202010)
Article History
Received: 12 October 2017
Accepted: 17 April 2018
First Online: 11 May 2018
Ethics approval and consent to participate
: The study was approved by the Sun Yat-sen University Ethics Committee, and all the parents/guardians of children signed the informed consent.
: The authors declare that they have no competing interests.
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