| artificial melanin | A dark pigment, resembling melanin, formed from glucosamines in chitin. Synonym: artificial melanin, factitious melanin. (05 Mar 2000) |
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| artificial neural net | Artificial Neural Nets (ANN) are computer models of biological nerve cell networks. (09 Oct 1997) |
| artificial organs | Devices intended to replace non-functioning organs. They may be temporary or permanent. Since they are intended always to function as the natural organs they are replacing, they should be differentiated from prostheses and implants and specific types of prostheses which, though also replacements for body parts, are frequently cosmetic (eye, artificial) as well as functional (artificial limbs). (12 Dec 1998) |
| artificial pacemaker | Any device that substitutes for the normal pacemaker and controls the rhythm of the organ; especially an electronic cardiac pacemaker, which may be implanted in the chest, with electrodes attached to the external cardiac surface, or passed through the venous circulation into the right side of the heart (pervenous pacemaker). (05 Mar 2000) |
| artificial passive immunity | See: acquired immunity. (05 Mar 2000) |
| artificial pneumothorax | Pneumothorax produced by the injection of air, or a more slowly absorbed gas such as nitrogen, into the pleural space to collapse the lung. (05 Mar 2000) |
| artificial pupil | An opening made by excision of a portion of the iris in order to improve the vision in cases of central opacity of the cornea or lens. (05 Mar 2000) |
| artificial respiration | Application of mechanically or manually generated pressures, usually positive, to gas(es) in or about the airway as a means of producing gas exchange between the lungs and surrounding atmosphere. Synonym: artificial respiration. (05 Mar 2000) |
| artificial selection | <genetics> The selective breeding by humans towards a desired trait in a plant, animal, or other organism which is of value (usually economic) to the humans. The process operates on the same principles as natural selection. (09 Oct 1997) |
| artificial sphincter | A sphincter produced by surgical procedures to reduce speed of flow in the digestive system or to maintain continence of the intestine. (05 Mar 2000) |
| artificial stone | A specially calcined gypsum derivative similar to plaster of Paris, but stronger, because the grains are nonporous. (05 Mar 2000) |
| artificial tears | Mixtures of fluid compounds to substitute for naturally produced t's. (05 Mar 2000) |
| artificial ventilation | Application of mechanically or manually generated pressures, usually positive, to gas(es) in or about the airway as a means of producing gas exchange between the lungs and surrounding atmosphere. Synonym: artificial respiration. (05 Mar 2000) |
| artificial Vichy salt | A mixture of sodium bicarbonate, anhydrous magnesium sulfate, potassium carbonate, and sodium chloride; an antacid. (05 Mar 2000) |
| artificial wetland | <ecology> Wetlands created by the activities of man, either purposefully or accidentally. (09 Oct 1997) |