a substance that makes another substance active or reactive, induces a chemical reaction, or combines with an enzyme to increase its catalytic activity.
tissue plasminogen activator
(TPA, t-PA) (t-plasminogen activator
) a serine endopeptidase synthesized by endothelial cells, the major physiologic activator of plasminogen
; when bound to fibrin
clots it catalyzes the conversion of plasminogen to plasmin
by hydrolysis of a specific arginine-valine bond. It can be produced by recombinant technology for use in thrombolytic therapy
. It acts directly on blood clots and therefore presents a small risk of systemic bleeding; occasionally allergic reactions may occur.
(urinary plasminogen activator
) a serine endopeptidase that acts as a plasminogen activator by catalyzing the preferential cleavage of plasminogen at the same arginine-valine bond where t-plasminogen activator
cleaves. It is produced in the kidney and excreted in the urine and is used in thrombolytic therapy
(when used as a pharmaceutical, it is usually called urokinase
). Unlike t-plasminogen activator or prourokinase, it does not require fibrin
for activity. Called also urokinase
1. A substance that renders another substance (for example, a catalyst) active, or that accelerates a process or reaction.
2. The fragment produced by chemical cleavage of a proactivator, that induces the enzymic activity of another substance.
3. An apparatus for making substances radioactive (for example, a neutron generator or a cyclotron).
4. A removable type of myofunctional orthodontic appliance that acts as a passive transmitter of force, produced by the function of the activated muscles, to the teeth and alveolar process that are in contact with it.
5. A protein that binds to a DNA sequence before RNA polymerase transcription, sometimes referred to as coactivator.
activator /ac·ti·va·tor/ (ak´tĭ-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.
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
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.
formal name for urokinase.
Called also urinary plasminogen a.
1 a substance, force, or device that stimulates activity in another substance or structure, especially a substance that activates an enzyme.
2 a substance that stimulates the development of an anatomical structure in the embryo.
3 an internal secretion of the pancreas.
4 an apparatus for making substances radioactive, such as a cyclotron or neutron generator.
5 (in dentistry) a removable orthodontic appliance that functions as a passive transmitter and stimulator of the perioral muscles.
Activator A protein that binds DNA at transcription control or enhancer sites—e.g., for an allosteric enzyme—and upregulates—i.e., positively regulates—gene transcription. Activators either increase binding of RNA polymerase to the promoter site or stimulate RNA polymerase to begin transcription.
1. A substance that renders another substance active, or one that accelerates a process or reaction.
2. The fragment, produced by chemical cleavage of a proactivator, which induces the enzymatic activity of another substance.
3. An apparatus for making substances radioactive.
4. A removable type of myofunctional orthodontic appliance that acts as a passive transmitter of force, which is produced by the function of the activated muscles, to the teeth and alveolar process that are in contact with it.
5. A protein that binds to a DNA sequence before DNA polymerase transcription.
6. Manually assisted thrust instrument that activates mechanoreceptors; used by many chiropractors.
activator any drug that increases the activity level of the person being treated.
n a chiropractic technique that employs a device that, when applied to joints, muscles, and soft tissues, conveys a powerful impulse to correct subluxations.
1. A substance that renders another substance active, or accelerates a process or reaction.
A removable type of myofunctional orthodontic appliance that acts as a passive transmitter of force, produced by the function of the activated muscles, to the teeth and alveolar process that are in contact with it.
See also: accelerator
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
a substance that makes another substance active or that renders an inactive enzyme capable of exerting its proper effect.
a substance that activates plasminogen and converts it into plasmin.
Patient discussion about activator
Q. Are there any nice activities for adults with autism? I've been helping a very nice man of 45 of years old and I'm looking for some new things I can do with him in our time together. any ideas?
A. Autistic people react wonderfully with animals. for instance- i saw a group of severe Autistic teenagers going to swim with dolphins. the effect was amazing! taking him to the zoo, or even to the park to feed ducks, pet dogs, whatever.. could have a great effect on him.
hope i helped!
tell me how it went.
Q. what is a passive smoking? and is it dangerous as an active?
A. Passive smoking is the exposure to cigarettes smoke emitted from cigarettes smoke by other person. It's dangerous and may increase the risk to several diseases similar to active smoking (one's exposure to smoke emitted from the cigarettes he or she is smoking) although the risk is of lower magnitude. Example for passive smoking is children of smokers etc.
You may read more here:http://www.nlm.nih.gov/medlineplus/secondhandsmoke.html
Q. i swim a lot ! what are the advantages of swimming over other sport activities? on what part of the body does it work the most ?
A. its a good workout but your not really going to burn as much calories as a regular work out.More discussions about activator