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.
Brain natriuretic peptide concentration (log), measured by the direct (A) and extracted (B) assays in plasma separated and stored immediately at −70°C, or kept for 72 hours as whole blood at room temperature. Line of identity is shown.