Funding for this research was provided by:
Guangzhou Institute of Pediatrics/Guangzhou Women and Children Medical Center (YIP-2019-023)
Guangzhou Science and Technology Department (201804010142)
Guangdong Science and Technology Department (2016ZC0227)
Article History
Received: 18 February 2020
Accepted: 7 May 2020
First Online: 24 May 2020
Ethics approval and consent to participate
: Written informed consent was waived by the Review Board of Guangzhou Women and Children's Medical Center Ethics Committee for this retrospective case series.
: Not application.
: We state that there are no conflicts of interest.