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Related to differential absorption: Differential Absorption LIDAR
Etymology: L, differentia, difference
the difference in absorption of x-rays by different body tissues. In a radiograph of a body part, such as an arm, the image of the bone is produced because more x-rays are absorbed by bone than by the surrounding soft tissue. Lowering the kilovolt peak of an x-ray beam increases differential absorption, but it also increases the patient dose. Also called selective absorption.
1. the act of taking up or in by specific chemical or molecular action; especially the passage of liquids or other substances through a surface of the body into body fluids and tissues, as in the absorption of the end products of digestion into the villi that line the intestine.
2. in radiology, uptake of energy by matter with which the radiation interacts.
any process by which one substance in liquid or solid form penetrates the surface of another substance.
Compton absorption effect
see compton effect.
the difference in the absorption of x-rays by different tissues.
the passage of the end products of digestion from the gastrointestinal tract into the blood and lymphatic vessels and the cells of tissues. Absorption of this kind can take place either by diffusion or by active transport.
a passive process in which noxious or therapeutic substances pass through the skin into the body.
the dissipation of radiant energy as it passes through matter. This phenomenon is of particular importance in diagnostic and therapeutic radiology, which depends on the interaction between ionizing radiations and matter. As radiation passes through matter, it is absorbed by an amount dependent on the atomic and molecular structure and thickness of the substance, and the energy of the primary photons. If radiations pass through a medium of living or nonliving material without absorption (loss of energy), no biological or photographic effects can occur. In true absorption the photons of radiation waves give up or transfer all of their energy to electrons within the atoms of the matter through which they are passing.
exhibiting or depending on a difference.
see differential absorption.
differential cell count
see differential count.
the differences between diseases in terms of clinical signs and epidemiological parameters; used as a basis for selecting as a diagnosis the one with the best fit to those seen in the subject.
differential leukocyte count
see differential count.
differential milk cell counts
count of cells in a milk sample including individual counts of somatic cells and individual leukocyte types.
differential thromboplastin time
used in differentiating the cause of hemophilia. Reagents containing either factor VIII or factor IX are added in the partial thromboplastin time test to demonstrate which factor corrects the prolonged clotting time.