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.
Zhou X, Meier I.Zhou X, et al.Proc Natl Acad Sci U S A. 2014 Aug 12;111(32):11900-5. doi: 10.1073/pnas.1323104111. Epub 2014 Jul 29.Proc Natl Acad Sci U S A. 2014.PMID: 25074908Free PMC article.