Internal Medicine is an open-access online only journal published monthly by the Japanese Society of Internal Medicine.Articles must be prepared in accordance with "The Uniform Requirements for Manuscripts Submitted to Biomedical Journals (see Annals of Internal Medicine 108: 258-265, 1988), must be contributed solely to the Internal Medicine, and become the property of the Japanese Society of Internal Medicine. Statements contained therein are the responsibility of the author(s). The Society reserves copyright and renewal on all published material and such material may not be reproduced in any form without the written permission of the Society.