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Subject: GLOSSARY (b)
Date: November 1989 from BETA #3 and BETA #4 (5 items)

baseline:

A known value with which later measurements can be compared (e.g., baseline temperature, baseline hemoglobin level.)

bioavailability:

The rate and extent to which a substance is absorbed and circulated within the body.

blood-cerebrospinal fluid barrier:

A barrier between the blood and the fluid surrounding the brain and spinal column. It only allows some substances to pass from the blood to the fluid. This barrier presents a potential problem in treating HIV infection because treatments must cross it to stop HIV infection in the brain.

bone marrow cell pool:

Those bone marrow cells responsible for the production of blood cells.

bronchodilating:

Anything that opens or expands the bronchi (that part of the body that conveys air to and from the lungs). Bronchodilating drugs can reduce coughing, wheezing, and shortness of breath.