An official website of the United States government
Here's how you know
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.
As a library, NLM provides access to scientific literature. Inclusion in an NLM database does not imply endorsement of, or agreement with,
the contents by NLM or the National Institutes of Health.
Learn more:
PMC Disclaimer
|
PMC Copyright Notice
1Laboratory of Physiological Hygiene, University of Minnesota, Minneapolis
1
This work has been supported in part by a fellowship grant from Frederick Stearns and Company. Assistance was also contributed by the Works Progress Administration as a part of Sub-project 380, University of Minnesota Project 8760.