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.
Singer DE, Albers GW, Dalen JE, Fang MC, Go AS, Halperin JL, Lip GYH, Manning WJ.Singer DE, et al. Among authors: fang mc.Chest. 2008 Jun;133(6 Suppl):546S-592S. doi: 10.1378/chest.08-0678.Chest. 2008.PMID: 18574273