Funding for this research was provided by:
National Natural Science Foundation of China (81600400)
Natural Science Foundation of Guangdong Province (2016A030310250)
China Postdoctoral Science Foundation (2017T100621)
Guangzhou Institute of Pediatrics/Guangzhou Women and Children's Medical Center (0170085, 1600019)
Received: 20 September 2020
Accepted: 29 December 2020
First Online: 19 January 2021
Ethics approval and consent to participate
: This study was approved by the Ethics Committee of the Guangzhou Women and Children's Medical Center (Approval No. 2016042036). All procedures performed in studies involving human participants were per the ethical standards of the institutional review board of Guangzhou Women and Children's Medical Center and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. Written informed consent was obtained from all individual participants included in this study.
: Not applicable.
: The authors declare that they have no competing interests.