Funding for this research was provided by:
National Natural Science Foundation of China (81471329, 81211140048, 81200463, 81201013)
Received: 24 April 2018
Accepted: 4 June 2018
First Online: 15 June 2018
Ethics approval and consent to participate
: The present research was conducted in accordance with the Declaration of Helsinki and approved by the ethics committee of Chinese PLA General Hospital.
: The written informed consent was obtained from the parent/caregiver of each child before trial-related procedures were performed.
: The authors declare that they have no competing interests. The corresponding author had full access to all the data in the study and had final responsibility for the decision to submit for publication.
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