Full text
PDF
. 1938 Aug 15;93(3):301–304. doi: 10.1113/jphysiol.1938.sp003641
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.