| AMI | Acute Myocardial Infarction - Complications(Cx) 1. Early ... |
|---|---|
| VF | left leg [electrode]; ventricular fibrillation; ventricular fluid; ventricular flutter; visual field... |
| RAS | 1) Reticular Activating(Activation) System 2) Renal Artery Stenosis |
| ADR | activation, depression, repetition [in bone remodeling]; adrenodoxin reductase; Adriamycin; adverse ... |
| AE | above-elbow [amputation]; acrodermatitis enteropathica; activation energy; adult erythrocyte; advers... |
| trans-activation (genetics) | Increased rate of gene expression directed by either viral or cellular proteins. These regulatory factors (diffusible gene products) act in trans -- that is, act on homologous or heterologous molecules of DNA. (cis-acting factors act only on homologous molecules.) (12 Dec 1998) |
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| energy of activation | Energy that must be added to that already possessed by a molecule or molecules in order to initiate a reaction; usually expressed in the Arrhenius equation relating a rate constant to absolute temperature. (05 Mar 2000) |
| enzyme activation | Conversion of an inactive form of an enzyme to one possessing metabolic activity. It includes 1) activation by ions (activators); 2) activation by cofactors (coenzymes); and 3) conversion of an enzyme precursor (proenzyme or zymogen) to an active enzyme. (12 Dec 1998) |
| juxtacrine activation | Activation of target cells by membrane anchored growth factors, also used for activation of leucocytes by PAF bound to endothelial cell surface. (18 Nov 1997) |
| feedback activation | The activation of an enzyme by an end product of a biochemical pathway in which that enzyme plays a part. For example, the activation of factors VIII and V by thrombin during blood clotting. (05 Mar 2000) |
| feed-forward activation | The activation of an enzyme by a precursor of the substrate of that enzyme. (05 Mar 2000) |
| upstream activation site | A DNA sequence that regulates transcription like an enhancer but does notwork if its located downstream from a promoter. (09 Oct 1997) |
| low-activation materials | <radiobiology> In fission reactors, one is forced to deal with the radioactive byproducts of the fission process, but in fusion reactors one generally has a choice of what materials to expose to neutrons produced by the fusion process. A major problem for fusion reactors is developing materials (such as for the reactor vacuum vessel structure) which can be exposed to high levels of neutron bombardment without becoming permanently radioactive. Candidate structural materials which have relatively low induced radiactivation (generally relative to stainless steel) are known as low-activation materials, these include titanium, vanadium, and silicon-carbide. (09 Oct 1997) |
| lymphocyte activation | <haematology> The change in morphology and behaviour of lymphocytes exposed to a mitogen or to an antigen to which they have been primed. The result is the production of lymphoblasts, cells that are actively engaged in protein synthesis and that divide to form effector populations. Should not be confused with transformation of the type associated with oncogenic viruses and activation is therefore perhaps a better term. (18 Nov 1997) |
| aberrant ventricular conduction | Abnormal intraventricular conduction of a supraventricular beat, especially where surrounding beats are normally conducted. Synonym: ventricular aberration. (05 Mar 2000) |
| aortico-left ventricular tunnel | Congenital connection between the aorta above exit of coronary arteries and the left ventricle. (05 Mar 2000) |
| arrhythmias, ventricular | Abnormal rapid heart rhythms (arrhythmias) that originate in the lower chambers of the heart (the ventricles). Ventricular arrhythmias include ventricular tachycardia and ventricular fibrillation. Both are life threatening arrhythmias most commonly associated with heart attacks or scarring of the heart muscle from previous heart attack. (12 Dec 1998) |
| arrhythmogenic right ventricular dysplasia | A congenital cardiomyopathy in which transmural infiltration of adipose tissue results in weakness and aneurysmal bulging of the infundibulum, apex, and posterior basilar region of the right ventricle and leads to ventricular tachycardia arising in the right ventricle. (12 Dec 1998) |
| atrial ventricular canal defect | A defect caused by deficient or absent septal tissue immediately above and below the normal level of the atrioventricular valves, including the region normally occupied by the A-V septum in hearts with two ventricles. The A-V valves are abnormal to a varying degree. (05 Mar 2000) |
| bidirectional ventricular tachycardia | Ventricular tachycardia in which the QRS complexes in the electrocardiogram are alternately mainly positive and mainly negative; many such cases may represent ventricular tachycardia with alternating forms of aberrant ventricular conduction. (05 Mar 2000) |