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.
Rosenstein Y, Kretschmer RR, Lafarge-Frayssinet C.Rosenstein Y, et al.Immunology. 1981 Nov;44(3):555-60.Immunology. 1981.PMID: 6976308Free PMC article.