alternating current

current /cur·rent/ (kur´ent)

1. anything that flows.

2. electric c.

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action current  the current generated in the cell membrane of a nerve or muscle by the action potential.

alternating current  a current which periodically flows in opposite directions.

convection current  a current caused by movement by convection of warmer fluid into an area of cooler fluid.

direct current  a current flowing in one direction only.

electric current  the stream of electricity that moves along a conductor. Symbol I .

galvanic current  a steady direct current, especially one produced chemically.

current of injury  a flow of current to (systolic c. of injury) or from (diastolic c. of injury) the injured region of an ischemic heart, due to regional alteration in transmembrane potential.

pacemaker current  the small net positive current flowing into certain cardiac cells, such as those of the sinoatrial node, causing them to depolarize.

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alternating current (AC)

[ôl′tərnā′ting]

an electric current that reverses direction, according to a consistent sinusoidal pattern. Compare direct current. See also current.

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current [kur´ent]

1. something that flows.

2. specifically, electricity transmitted through a circuit.

alternating current a current that periodically flows in opposite directions; its amplitude fluctuates as a sine wave.

convection current a current caused by movement by convection of warmer fluid into an area of cooler fluid.

direct current a current that flows in one direction only; when modeled as a wave, its amplitude is constant. When used medically it is called galvanic current. This current has distinct and important polarity and marked secondary chemical effects.

galvanic current a steady direct current.

current of injury an electric current that flows between injured myocardium and normal myocardium, because such cells have a reduced membrane potential; it may be either diastolic or systolic.

current of injury, diastolic the current that flows from injured to noninjured tissue during electrical diastole.

current of injury, systolic the current that flows from healthy tissue to injured tissue during electrical systole.

inwardly rectifying current current that rectifies so that it passes more easily towards the interior of a cell.

leakage current the electrical current that exists in the parts or metal case of electrical equipment.

outwardly rectifying current current that rectifies so that it passes more easily towards the exterior of a cell.

potassium rectifying c's transmembrane currents that rectify inwardly or outwardly to make adjustments in cellular functions; they are mainly responsible for the repolarization phase of the action potential. There are at least six mechanisms by which potassium ions move across cardiac cell membranes in the role of rectifier.

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current,

n a measure of the number of electrons per second that pass a given point on a conductor.

current, alternating,

n a current that alternately changes its direction of flow. It usually consists of 60 complete cycles/sec.

current, coagulating,

n an electrical current, delivered by a needle, ball, or other variously shaped points, that coagulates tissue.

current dental terminology (CDT),

n a listing of descriptive terms and identifying codes developed by the American Dental Association (ADA) for reporting dental services and procedures to dental benefits plans.

current, direct,

n an electrical current in which the electron flow is in only one direction.

current, galvanic,

n a direct current created by a battery.

current procedural terminology (CPT),

n a listing of descriptive terms and identifying codes developed by the American Medical Association (AMA) for reporting practitioner services and procedures to medical plans and medicare.

n the maximum current in a roentgen-ray tube that fully uses all electrons that are available at the cathode for the production of roentgen rays.

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current

that which flows; electric transmission in a circuit.

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alternating current

a current that flows in opposite directions sinusoidally.

direct current

a current whose direction is always the same.