- blood analysis
Laboratory examination of the physical and chemical properties and components of a sample of blood.Analysis includes number of red and white blood cells (erythrocytes and leukocytes); red cell volume, sedimentation (settling) rate, and hemoglobin concentration; blood typing; cell shape and structure; hemoglobin and other protein structure; enzyme activity; and chemistry. Special tests detect substances characteristic of specific infections.
* * *laboratory examination of a sample of blood to obtain information about its physical and chemical properties. Blood analysis is commonly carried out on a sample of blood drawn from the vein of the arm, the finger, or the earlobe; in some cases, the blood cells of the bone marrow may also be examined. Hundreds of hematological tests and procedures have been developed, and many can be carried out simultaneously on one sample of blood with such instruments as autoanalyzers. Blood analysis includes the following areas of study:● Determination of the number of red blood cells (erythrocytes (erythrocyte)) and white blood cells (leukocytes (lymphocyte)) in the blood, together with the volume, sedimentation rate, and hemoglobin concentration of the red blood cells ( blood count).● Classification of the blood according to specific red blood cell antigens (antigen), or blood groups (see blood typing).● Elucidation of the shape and structural details of blood cells.● Study of the structure of hemoglobin and other blood proteins.● Determination of the activity of various enzymes, or protein catalysts, that either are associated with the blood cells or are found free in the blood plasma.● Study of blood chemistry.Other properties of blood that may be included in an analysis are total volume, circulation time, viscosity, clotting time and clotting abnormalities, acidity (pH), level of oxygen and carbon dioxide, and clearance rate of various substances (see kidney function test). In addition to the wide variety of procedures devised for the study of normal blood constituents, there are also special tests based on the presence in the blood of substances characteristic of specific infections, such as the serological tests (serological test) for syphilis, hepatitis, and human immunodeficiency virus (HIV; the AIDS virus).
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