Funding for this research was provided by:
Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (2016R1D1A1B03933125)
Text and Data Mining valid from 2018-05-23
Received: 30 March 2018
Accepted: 14 May 2018
First Online: 23 May 2018
Ethics approval and consent to participate
: The Korea Centers for Disease Control and Prevention obtained written informed consent from all participants, and the Institutional Review Board of Severance Hospital approved this study protocol (4–2015-1071).
: The authors declare that they have no competing interests.
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