Funding for this research was provided by:
Asan Institute for Life Sciences, Asan Medical Center (2016-7023)
Received: 12 July 2018
Accepted: 30 January 2019
First Online: 4 February 2019
Ethics approval and consent to participate
: This study was approved by the Institutional Review Board of Asan Medical Center (AMC IRB 2016–1324). Informed consent was waived by the AMC IRB.
: Not applicable.
: The authors declare that they have no competing interests.
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