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.
Hadjantonakis A, Papaioannou V.Hadjantonakis A, et al.Differentiation. 2001 Oct;68(4-5):159-66. doi: 10.1046/j.1432-0436.2001.680403.x.Differentiation. 2001.PMID: 11776468Review.