| no-observed-adverse-effect level | The highest dosage administered that does not produce toxic effects. The noael will depend on how closely dosages are spaced (lowest-observed-adverse-effect level and no-observed-effect level) and the number of animals examined. The ultimate objective is usually to determine not the "safe" dosage in laboratory animals but the "safe" dosage for humans. Therefore, the extrapolation most often required of toxicologists is from high-dosage studies in laboratory animals to low doses in humans. (casarett and doull's toxicology: the basic science of poisons, 4th ed) (12 Dec 1998) |
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| adverse effect | This is an abnormal or harmful effect to an organism caused by exposure to a chemical. It is indicated by some result such as death, a change in food or water consumption, altered body and organ weights, altered enzyme levels, or visible illness. An effect may be classed as adverse if it causes functional or anatomical damage, causes irreversible change in the homeostasis of the organism, or increases the susceptibility of the organism to other chemical or biological stress. A non-adverse effect will usually be reversed when the organism is no longer being exposed to the chemical. (09 Oct 1997) |
| lowest achievable emissions rate | (LAER) Used to describe air emissions control technology. A rate of emissions defined by the permitting agency. LEAR sets emission limits for non-attainment areas. (05 Dec 1998) |
| lowest lumbar arteries | Origin, middle sacral; distribution, sacrum and iliac muscle; anastomosis, deep circumflex iliac artery. Synonym: arteriae lumbales imae. (05 Mar 2000) |
| lowest splanchnic nerve | <anatomy, nerve> One of the abdominopelvic splanchnic nerves arising in the thorax and penetrating the diaphragm to supply presynaptic sympathetic fibres for the renal plexus; often combined with the lesser splanchnic nerve, but occasionally existing as an independent nerve. Synonym: nervus splanchnicus imus, smallest splanchnic nerve. (05 Mar 2000) |
| lowest thyroid artery | <anatomy, artery> An inconstant artery; origin, arch of aorta or brachiocephalic artery; distribution, thyroid gland. Synonym: arteria thyroidea ima, lowest thyroid artery, Neubauer's artery. (05 Mar 2000) |
| adverse | Harmful. (18 Nov 1997) |
| adverse drug reaction reporting systems | Systems developed for collecting reports from government agencies, manufacturers, hospitals, physicians, and other sources on adverse drug reactions. (12 Dec 1998) |
| adverse event | A toxic reaction to a medical therapy. (09 Oct 1997) |
| adverse reaction | Any undesirable or unwanted consequence of a preventive, diagnostic, or therapeutic procedure or regimen. (05 Mar 2000) |
| event, adverse | In pharmacology, an adverse event is any unexpected or dangerous reaction to a drug. (12 Dec 1998) |
| ACE level | <investigation> This is a blood test which measures the concentration of angiotensin-converting enzyme (ACE) in the bloodstream. Elevations in angiotensin-converting enzyme are seen sarcoidosis, histoplasmosis, alcoholic cirrhosis, asbestosis, berylliosis, diabetes, Hodgkin's disease, hyperthyroidism, amyloidosis, primary biliary cirrhosis, idiopathic pulmonary fibrosis, pulmonary embolism, scleroderma, silicosis, tuberculosis, Gaucher's disease and leprosy. The normal values are 18 to 67 U/ml over 20 years of age (people under 20 have higher levels). (15 Jan 1998) |
| acoustic reference level | The biological reference level for sound measurements. When the term decibel is used to indicate the noise level, a reference quantity is implied; this reference value is usually expressed as a sound pressure of 20 micronewtons per square meter. The reference level is referred to as 0 decibels, the baseline of the scale of noise level's; this baseline is considered the weakest sound that can be heard by a person with very good hearing in an extremely quiet location. Other equivalent reference level's still being used include 0.0002 microbar and 0.0002 dyne per square centimeter. (05 Mar 2000) |
| background level | The average amount of a substance present in the environment. Originally referring to naturally occurring phenomena. Used in toxic substance monitoring. (05 Dec 1998) |
| blood porphyrin level | A test which is used to measure red blood cell porphyrin levels. Porphyrins are pigments found in both animal and plant life. This test is useful in evaluating any number of porphyrin disorders (involving the various porphyrins) of red blood cells. Increased levels of coproporphyrins can indicate congenital erythropoietic porphyria or sideroblastic anaemia. Increased protoporphyrins may be seen in infection, thalassaemia, sideroblastic anaemia, iron deficient anaemia, increased erythropoiesis and lead poisoning. Increased uroporphyrins may indicate congenital erythropoietic porphyria or erythropoietic protoporphyria. (27 Sep 1997) |