Funding for this research was provided by:
Pearl River S and T Nova Program of Guangzhou (201710010039)
Natural Science Foundation of Guangdong Province (2017A030313898, 2017A030313620)
Applied Basic Research Foundation of Yunnan Province (17ykpy48)
Science and Technology Program of Guangdong Province (2017A020215028)
Science and Technology Program of Guangzhou (201707010113)
Text and Data Mining valid from 2018-12-05
Received: 15 October 2018
Accepted: 3 December 2018
First Online: 5 December 2018
Compliance with ethical standards
: All authors declare no conflict of interest.
: The study was approved by the institutional review board and the ethics committee of the Third Affiliated Hospital of Sun Yat-sen University, and all procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.
: Written informed consent was obtained from all children’ parents.