Abstract
Full text
PDFPage 6787
. 1985 Sep 25;13(18):6787. doi: 10.1093/nar/13.18.6787
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.
