| OAR | organ at risk |
|---|---|
| OBF | organ blood flow |
| OC | obstetrical conjugate; occlusocervical; office call; on call; only child; optic chiasma; oral contra... |
| OPO | Organ Procurement Organization |
| OS | left eye [Lat. oculus sinister]; occipitosacral; occupational safety; office surgery; Omenn syndrome... |
| end-diastolic | 1. Occurring at the end of diastole, immediately before the next systole, as in end-diastolic pressure. 2. Interrupting the final moments of diastole, barely premature, as in end-diastolic extrasystole. (05 Mar 2000) |
|---|---|
| end-diastolic volume | The amount of blood in the ventricle immediately before a cardiac contraction begins; a measurement of cardiac filling between beats, related to diastolic function. (05 Mar 2000) |
| end-feet | The somewhat enlarged, often club-shaped endings by which axons make synaptic contacts with other nerve cells or with effector cells (muscle or gland cells). As isolated, by homogenizing brain or spinal cord, they contain acetylcholine and the related enzymes. Terminals contain neurotransmitters of various kinds, sometimes more than one. These can be demonstrated by chemical analysis and immunocytochemical methods. See: synapse. Synonym: axonal terminal boutons, end-feet, neuropodia, pieds terminaux, synaptic boutons, synaptic endings, synaptic terminals, terminal boutons, bouton terminaux. (05 Mar 2000) |
| end-filling | The use of DNA polymerase to create a blunt end (both strands are the same length and end together) on double-stranded DNA that has a staggered end (one strand is longer than the other so there is a single-stranded section at the end of the molecule). (09 Oct 1997) |
| end-on mattress suture | A vertical mattress suture used for exact skin approximation. (05 Mar 2000) |
| end oxidation | <biochemistry> The last oxidation step in a catabolic pathway. Synonym: terminal oxidation. (05 Mar 2000) |
| end-piece | The terminal part of the tail of a spermatozoon consisting of the axoneme and the flagellar membrane. (05 Mar 2000) |
| end plate | <anatomy, physiology> The area of sarcolemma immediately below the synaptic region of the motor neuron in a neuromuscular junction. most often refers to the end of a nerve fibre against a skeletal muscle fibre, to which it transmits nerve signals. (18 Nov 1997) |
| end plate potential | <physiology> Depolarisation of the sarcolemma as a result of acetylcholine release from the motoneuron causing an influx of sodium ions. The endplate potential is the sum of quantal miniature endplate potentials. Development of the end plate potential is blocked by curare. (18 Nov 1997) |
| end point | <chemistry> It is the completion point during a titration reaction where there are equal amounts of titrant and whatever is being titrated. It is usually evident by the first perceptible alteration of the colour of an added indicator. <immunology> It is the most dilute an antibody or antiserum solution can be while still detectably reacting with the antigen. <statistics> A category of data used to compare the outcome in different arms of a clinical trial. Common endpoints are severe toxicity, disease progression or fall in such surrogate markers as CD4 count, but sometimes death is used as an endpoint. (08 Mar 2000) |
| end-point measurement | Analytical measurement at the end of a chemical reaction, as opposed to making the measurement while the reaction proceeds. (05 Mar 2000) |
| end-point nystagmus | A jerky, physiologic nystagmus occurring in a normal individual when attempts are made to fixate a point at the limits of the field of fixation. Synonym: deviational nystagmus. (05 Mar 2000) |
| end product | <biochemistry> The final product of after a series of reactions with enzymes in a biochemical metabolic pathway has taken place. (09 Oct 1997) |
| end product inhibition | <biochemistry, physiology> The process of the end product of a particular metabolic reaction inhibiting an allosteric enzyme involved in that reaction as the reaction starts again, thus breaking the reaction cycle. (09 Oct 1997) |
| end product repression | Catabolite repression in which the catabolite is an end product of a particular pathway. (05 Mar 2000) |