Funding for this research was provided by:
grant from National Nature Foundation of China (81371988)
Major science and technology program for medical and health of Zhejiang Province (WKJ-ZJ-1527)
Received: 25 October 2017
Accepted: 23 January 2018
First Online: 8 February 2018
Ethics approval and consent to participate
: This study was approved by the IRB (Institutional Review Board) of the Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University. Patient’s consent to participate was not required in this retrospective study.
: Not applicable.
: The authors declare that they have no competing interests.
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