Funding for this research was provided by:
the National Key Research and Development Program of China (2016YFC1000500)
Received: 29 December 2018
Accepted: 16 May 2019
First Online: 28 May 2019
Ethics approval and consent to participate
: The local ethics committee of Fudan University approved this study, and written informed consent was obtained from the parents or relatives of all study individuals.
: Not applicable.
: The authors declare that they have no competing interests.
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