. 2013 Oct 29;28(6):728–731. doi: 10.3904/kjim.2013.28.6.728
Copyright © 2013 The Korean Association of Internal Medicine
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.