activator

activator /ac·ti·va·tor/ (ak´ti-va?ter)

1. a substance that combines with an enzyme to increase its catalytic activity.

2. a substance that stimulates the development of a specific structure in the embryo.

3. a chemical or other form of energy that causes another substance to become reactive or that induces a chemical reaction.

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plasminogen activator  any of a group of substances that have the ability to cleave plasminogen and convert it into the active form plasmin.

prothrombin activator  any one of the substances in the extrinsic or intrinsic pathways of coagulation.

single chain urokinase-type plasminogen activator  (scu-PA) prourokinase.

tissue plasminogen activator  (TPA) (t-PA), t-plasminogen activator an endopeptidase synthesized by endothelial cells that binds to fibrin clots and catalyzes the cleavage of plasminogen to the active form plasmin. t-PA produced by recombinant technology is used for therapeutic thrombolysis.

u-plasminogen activator  formal name for urokinase. Called also urinary plasminogen a.

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ac·ti·va·tor (kt-vtr)

n.

1. An agent that renders another substance active or accelerates a process or reaction.

2. The fragment produced by chemical cleavage of a proactivator that induces the enzymatic activity of another substance.

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activator (ak·ti·vāˑ·ter),

n a chiropractic technique that employs a device that, when applied to joints, muscles, and soft tissues, conveys a powerful impulse to correct subluxations.

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activator (ak´tivātur),

n 1. an alkali, sodium carbonate, which is a component of photographic developing solution that softens and swells the gelatin of the film emulsion and provides the necessary alkaline medium for the developing agents to react with the sensitized silver halide crystals.
n 2. in orthodontics, a removable orthodontic appliance intended to function as a passive transmitter and sometimes stimulator of the forces of the perioral muscles. One in the myofunctional category of appliances also known by such names as
Andresen, Bimler, Monobloc, and
Frankel.

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activator

a substance that makes another substance active or that renders an inactive enzyme capable of exerting its proper effect.

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developing activator

see developing accelerator.

plasminogen activator

a substance that activates plasminogen and converts it into plasmin.