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.
Barsky SH, Roth MD, Kleerup EC, Simmons M, Tashkin DP.Barsky SH, et al. Among authors: tashkin dp.J Natl Cancer Inst. 1998 Aug 19;90(16):1198-205. doi: 10.1093/jnci/90.16.1198.J Natl Cancer Inst. 1998.PMID: 9719080
Tashkin DP, Rand C, Nides M, Simmons M, Wise R, Coulson AH, Li V, Gong H Jr.Tashkin DP, et al.Am J Med. 1991 Oct 21;91(4A):33S-36S. doi: 10.1016/0002-9343(91)90260-5.Am J Med. 1991.PMID: 1951401Clinical Trial.