An official website of the United States government
The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before
sharing sensitive information, make sure you’re on a federal
government site.
The site is secure.
The https:// ensures that you are connecting to the
official website and that any information you provide is encrypted
and transmitted securely.
Smit LA, Heederik D, Doekes G, Blom C, van Zweden I, Wouters IM.Smit LA, et al. Among authors: wouters im.Eur Respir J. 2008 Jun;31(6):1241-8. doi: 10.1183/09031936.00090607. Epub 2008 Feb 6.Eur Respir J. 2008.PMID: 18256063Free article.