Volume of circulating ERYTHROCYTES . It is usually measured by RADIOISOTOPE DILUTION TECHNIQUE.

Determination of the energy distribution of gamma rays emitted by nuclei. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)

The number of RED BLOOD CELLS per unit volume in a sample of venous BLOOD.

Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.

Stable chromium atoms that have the same atomic number as the element chromium, but differ in atomic weight. Cr-50, 53, and 54 are stable chromium isotopes.

Tests used in the analysis of the hemic system.

The number of LEUKOCYTES and ERYTHROCYTES per unit volume in a sample of venous BLOOD. A complete blood count (CBC) also includes measurement of the HEMOGLOBIN; HEMATOCRIT; and ERYTHROCYTE INDICES.

ERYTHROCYTE size and HEMOGLOBIN content or concentration, usually derived from ERYTHROCYTE COUNT; BLOOD hemoglobin concentration; and HEMATOCRIT. The indices include the mean corpuscular volume (MCV), the mean corpuscular hemoglobin (MCH), and the mean corpuscular hemoglobin concentration (MCHC).

The volume of packed RED BLOOD CELLS in a blood specimen. The volume is measured by centrifugation in a tube with graduated markings, or with automated blood cell counters. It is an indicator of erythrocyte status in disease. For example, ANEMIA shows a low value; POLYCYTHEMIA, a high value.

A plant genus of the family TILIACEAE. Members contain cycloartane saponins and CARDENOLIDES.

The oxygen-carrying proteins of ERYTHROCYTES. They are found in all vertebrates and some invertebrates. The number of globin subunits in the hemoglobin quaternary structure differs between species. Structures range from monomeric to a variety of multimeric arrangements.

An examination of chemicals in the blood.

The number of PLATELETS per unit volume in a sample of venous BLOOD.

The semi-permeable outer structure of a red blood cell. It is known as a red cell 'ghost' after HEMOLYSIS.

Experiments designed to determine the potential toxic effects of one-time, short-term exposure to a chemical or chemicals.

The number of WHITE BLOOD CELLS per unit volume in venous BLOOD. A differential leukocyte count measures the relative numbers of the different types of white cells.

The cells found in the body fluid circulating throughout the CARDIOVASCULAR SYSTEM.

A disease characterized by chronic hemolytic anemia, episodic painful crises, and pathologic involvement of many organs. It is the clinical expression of homozygosity for hemoglobin S.

Concentrated pharmaceutical preparations of plants obtained by removing active constituents with a suitable solvent, which is evaporated away, and adjusting the residue to a prescribed standard.

The senescence of RED BLOOD CELLS. Lacking the organelles that make protein synthesis possible, the mature erythrocyte is incapable of self-repair, reproduction, and carrying out certain functions performed by other cells. This limits the average life span of an erythrocyte to 120 days.