The content is available as a PDF (156.1 KB).
. 2002 Dec;130(4):1764–1769. doi: 10.1104/pp.006338
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.