Funding for this research was provided by:
National Research Foundation of Korea (NRF-2017R1D1A1B03031642)
Text and Data Mining valid from 2019-03-12
Received: 21 September 2018
Accepted: 3 March 2019
First Online: 12 March 2019
: The authors declare that they have no competing interests.
: The study design was approved by the institutional review boards of all involved centers (nos. H-1801-043-914, B-1801/447–409, and 20,180,124/30–2018-3/023) and complied with the Declaration of Helsinki. Informed consents were waived under this approval.
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