Full Text
The Full Text of this article is available as a PDF (76.6 KB).
letter . 2002 Mar;82(3):1681–1684. doi: 10.1016/S0006-3495(02)75520-3
Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.