Funding for this research was provided by:
Young Scientists Fund (81301424)
Received: 26 August 2018
Accepted: 21 December 2018
First Online: 9 January 2019
Ethics approval and consent to participate
: The study procedure was approved by the ethics committee of the Children’s Hospital of Chongqing Medical University, Chongqing, China. Written informed consent was obtained from parent or guardian of all participants.
: Not applicable.
: The authors declare that they have no competing interests.
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