Received: 31 August 2017
Accepted: 26 February 2018
First Online: 19 April 2018
Ethics approval and consent to participate
: Approved by the Institutional Review Board (IRB)/Independent Ethics Committee (IEC) of Jiangsu Province Hospital (The First Affiliated Hospital of Nanjing Medical University) at 300 Guangzhou Road, Nanjing 210,029, China. All subjects provided informed consent in written to take part in the study.
: Not applicable.
: The authors declare that they have no competing interests.
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