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.
Shipley JM, Wesselschmidt RL, Kobayashi DK, Ley TJ, Shapiro SD.Shipley JM, et al. Among authors: wesselschmidt rl.Proc Natl Acad Sci U S A. 1996 Apr 30;93(9):3942-6. doi: 10.1073/pnas.93.9.3942.Proc Natl Acad Sci U S A. 1996.PMID: 8632994Free PMC article.