| AR | absolute risk; accounts receivable; achievement ratio; actinic reticuloid [syndrome]; active resista... |
|---|---|
| EPR | early progressive resistance; electron paramagnetic resonance; electronic patient record; electrophr... |
| PR | by way of the rectum [Lat. per rectum]; far point [of accommodation] [Lat. punctum remotum]; palindr... |
| PVR | peripheral vascular resistance; perspective volume rendering; poliovirus receptor; postvoiding resid... |
| RVR | reduced vascular response; renal vascular resistance; repetitive ventricular response; resistance to... |
| essential gene | <genetics> Any gene that, if it does not workcorrectly, kills the organism. (09 Oct 1997) |
|---|---|
| essential hypertension | Hypertension without known cause. Synonym: idiopathic hypertension, primary hypertension. (05 Mar 2000) |
| essential oils | Plant products, usually somewhat volatile, giving the odours and tastes characteristic of the particular plant, thus possessing the essence, e.g., citral, pinene, camphor, menthane, terpenes; usually, the steam distillates of plants or oils of plants obtained by pressing out the rinds of a particular plant. See: volatile oil. (05 Mar 2000) |
| essential phthisis bulbi | A softening of the eyeball (ophthalmomalacia) and reduction in size, not due to inflammation. (05 Mar 2000) |
| essential progressive atrophy of iris | Progressive atrophy of the iris without inflammatory signs, characterised by patchy loss of all layers of the iris with hole formation, migration of the pupil, degeneration of the corneal endothelium, peripheral anterior synechiae, and secondary glaucoma; usually unilateral, predominantly affecting women in their middle years. (05 Mar 2000) |
| essential pruritus | Itching that occurs independently of skin lesions. (05 Mar 2000) |
| essential tachycardia | Persistent rapid action of the heart due to no discoverable organic lesion. (05 Mar 2000) |
| essential telangiectasia | Localised capillary dilation of undetermined origin. Synonym: angioma serpiginosum. (05 Mar 2000) |
| essential thrombocythaemia | A rare condition related to polycythaemia rubra vera characterised by the production of large numbers of abnormal platelets. Symptoms include haemorrhage, blood clots and enlargement of the spleen. Treatment varies according to the severity of the disease. (13 Nov 1997) |
| essential thrombocytopenia | A primary form of thrombocytopenia, in contrast to secondary forms that are associated with metastatic neoplasms, tuberculosis, and leukaemia involving the bone marrow, or with direct suppression of bone marrow by the use of chemical agents, or with other conditions. (05 Mar 2000) |
| essential tremor | <neurology> A tremor that is associated with purposeful movement or motor activity. Essential tremor is the most common form of tremor with no identifiable cause. Stress, anxiety and the use of stimulants (for example caffeine, decongestants) can often make the tremor worse. Treatment is usually not necessary for this benign condition. (27 Sep 1997) |
| fatty acids, essential | Fatty acids that cannot be synthesised by the human body and must be obtained from dietary sources, e.g., linoleic acids and linolenic acids. (12 Dec 1998) |
| airway resistance | The opposition of the tracheobronchial tree to air flow: the mouth-to-alveoli pressure difference divided by the air flow. (12 Dec 1998) |
| ampicillin resistance | Nonsusceptibility of a microbe to the action of ampicillin, a penicillin derivative that interferes with cell wall synthesis. (12 Dec 1998) |
| androgen resistance syndromes | A class of disorders associated with 5a-steroid reductase deficiency, testicular feminization, and related disorders. Compare: steroid 5a-reductase, Reifenstein's syndrome, infertile male syndrome, testicular feminization syndrome. (05 Mar 2000) |