. 2014 Jun 13;55(4):1028–1035. doi: 10.3349/ymj.2014.55.4.1028
© Copyright: Yonsei University College of Medicine 2014
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.