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.
Haffar O, Garrigues J, Travis B, Moran P, Zarling J, Hu SL.Haffar O, et al. Among authors: hu sl.J Virol. 1990 Jun;64(6):2653-9. doi: 10.1128/JVI.64.6.2653-2659.1990.J Virol. 1990.PMID: 2186175Free PMC article.
Estin CD, Stevenson US, Plowman GD, Hu SL, Sridhar P, Hellström I, Brown JP, Hellström KE.Estin CD, et al. Among authors: hu sl.Proc Natl Acad Sci U S A. 1988 Feb;85(4):1052-6. doi: 10.1073/pnas.85.4.1052.Proc Natl Acad Sci U S A. 1988.PMID: 3422478Free PMC article.