| NR | do not repeat [Lat. non repetatur]; nerve root; neural retina; neutral red; noise reduction; nonreac... |
|---|---|
| NV | nausea and vomiting; negative variation; neovascularization; next visit; nonveteran; normal value; n... |
| CEA | Carcino-Embryonic Antigen [HP 1825-6] ; Oncofetal Antigens ; Glycopro... |
| NA | Avogadro constant or number; nalidixic acid; Narcotics Anonymous; network administrator; neuraminida... |
| NFIRS | National Fire Incident Reporting System |
| permissible exposure limit | An occupational health standard to safeguard workers against dangerous contaminants in the workplace. (05 Mar 2000) |
|---|---|
| prenatal exposure delayed effects | Delayed effects on offspring of maternal or foetal prenatal exposure to drugs, radiation and other physical agents, manipulation, nutrition, stress, etc. (12 Dec 1998) |
| short-term exposure limit | The maximum concentration of a chemical to which workers may be exposed continuously for up to 15 minutes without danger to health or work efficiency and safety. (05 Mar 2000) |
| dental pulp exposure | The result of pathological changes in the hard tissue of a tooth caused by carious lesions, mechanical factors, or trauma, which render the pulp susceptible to bacterial invasion from the external environment. (12 Dec 1998) |
| inhalation exposure | The exposure to potentially harmful chemical, physical, or biological agents by inhaling them. (12 Dec 1998) |
| occupational exposure | The exposure to potentially harmful chemical, physical, or biological agents that occurs as a result of one's occupation. (12 Dec 1998) |
| environmental exposure | The exposure to potentially harmful chemical, physical, or biological agents in the environment or to environmental factors that may include ionizing radiation, pathogenic organisms, or toxic chemicals. (12 Dec 1998) |
| exposure | <radiobiology> A quantitative measure of x or gamma radiation at a certain place, based on its ability to produce ionisation in air. The former special unit of exposure was the roentgen (R). 1R = 2.58 x 10-4 C/kg. In the international system (SI unit), the special unit is coulomb per kilogram. (Exposure also is frequently used as a synonym for irradiation). (16 Dec 1997) |
| exposure dose | The radiation dose, expressed in roentgens, delivered at a point in free air. Synonym: air dose. (05 Mar 2000) |
| exposure keratitis | Inflammation of the cornea resulting from irritation caused by inability to close the eyelids. Synonym: lagophthalmic keratitis. (05 Mar 2000) |
| exposure odds ratio | <epidemiology> See Odds ratio. (05 Dec 1998) |
| analgesia, patient-controlled | Relief of pain, without loss of consciousness, through an analgesic agent administered by the patient. It has been used successfully to control postoperative pain, during labour, after burns, and in terminal care. The choice of agent, dose, and lockout interval greatly influence effectiveness. The potential for overdose can be minimised by combining small bolus doses with a mandatory interval between successive doses (lockout interval). (12 Dec 1998) |
| randomised controlled trial | A clinical trial that involves at least one test treatment and one control treatment, concurrent enrollment and follow-up of the test- and control-treated groups, and in which the treatments to be administered are selected by a random process, such as the use of a random-numbers table. Treatment allocations using coin flips, odd-even numbers, patient social security numbers, days of the week, medical record numbers, or other such pseudo- or quasi-random processes, are not truly randomised and a trial employing any of these techniques for patient assignment is designated simply a controlled clinical trial. (12 Dec 1998) |
| randomised controlled trials | Clinical trials that involve at least one test treatment and one control treatment, concurrent enrollment and follow-up of the test- and control-treated groups, and in which the treatments to be administered are selected by a random process, such as the use of a random-numbers table. Treatment allocations using coin flips, odd-even numbers, patient social security numbers, days of the week, medical record numbers, or other such pseudo- or quasi-random processes, are not truly randomised and trials employing any of these techniques for patient assignment are designated simply controlled clinical trials. (12 Dec 1998) |
| patient controlled analgesia | <anaesthetics, procedure> Self-administration of analgesics by a patient instructed in doing so, usually refers to self-dosing with intravenous opioid (for example, morphine) administered by means of a programmable pump. (16 Dec 1997) |