Received: 14 August 2018
Accepted: 30 November 2018
First Online: 12 December 2018
Ethics approval and consent to participate
: The study was reviewed and approved by the Medical Ethics Committee of The Second Affiliated Hospital of Fujian Medical University. All study participants, or their legal guardian, provided informed written consent prior to study enrollment.
: Not applicable.
: The authors declare that they have no competing interests.
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