| S/D ratio | Systolic / Diastolic ratio |
|---|---|
| C/N | carbon/nitrogen [ratio]; carrier/ noise [ratio] |
| DR | degeneration reaction; delivery room; deoxyribose; diabetic retinopathy; diagnostic radiology; digit... |
| ER | efficiency ratio; epigastric region; ejection rate; electroresection; emergency room; endoplasmic re... |
| L/P | lactate/pyruvate [ratio]; liver plasma [concentration]; lymph/plasma [ratio] |
| ventricular conduction | Conduction of the cardiac impulse through the ventricular myocardium, represented by the QRS complex in the electrocardiogram. H-R conduction time is from the onset of the first high frequency component of the His bundle electrogram to the onset of the QRS complex of the surface electrocardiogram (normally 43 ± 12 msec); H-V conduction time is from the onset of the first high frequency component of the His bundle electrogram to the onset of the ventricular electrogram (normally approximates the H-R interval but may be a little shorter). Synonym: ventricular conduction. (05 Mar 2000) |
|---|---|
| ventriculoatrial conduction | Conduction backward from the ventricles or from the A-V node into and through the atria. Synonym: retroconduction, ventriculoatrial conduction, V-A conduction. (05 Mar 2000) |
| retrograde conduction | Conduction backward from the ventricles or from the A-V node into and through the atria. Synonym: retroconduction, ventriculoatrial conduction, V-A conduction. (05 Mar 2000) |
| P-H conduction time | See: atrioventricular conduction. (05 Mar 2000) |
| concealed conduction | Conduction of an impulse through a part of the heart without direct evidence of its presence in the electrocardiogram; conduction is inferred only because of its influence on the subsequent cardiac cycle. (05 Mar 2000) |
| conduction | <physics, physiology> The transfer of sound waves, heat, nervous impulses or electricity. Origin: L. Conductio (18 Nov 1997) |
| conduction anaesthesia | Regional anaesthesia in which local anaesthetic solution is injected about nerves to inhibit nerve transmission; includes spinal, epidural, nerve block, and field block anaesthesia, but not local or topical anaesthesia. Synonym: block anaesthesia. (05 Mar 2000) |
| conduction analgesia | Use of local anaesthetic solution(s) to produce circumscribed areas of loss of sensation; a generic term including conduction, nerve block, spinal, epidural, field block, infiltration, and topical anaesthesia. Synonym: conduction analgesia. (05 Mar 2000) |
| conduction aphasia | A form of aphasia in which the patient understands spoken and written words, is aware of his deficit, and can speak and write, but skips or repeats words, or substitutes one word for another (paraphasia);word repetition is severely impaired. The responsible lesion is in the associate tracks connecting the various language centres. Synonym: associative aphasia. (05 Mar 2000) |
| conduction block | Failure of impulse transmission at some point along a nerve, although conduction along the segments proximal and distal to it are unaffected. Clinically, most often caused by an area of focal demyelination; when caused by focal trauma, called neurapraxia. (05 Mar 2000) |
| heart conduction system | An impulse-conducting system composed of modified cardiac muscle and having the power of spontaneous rhythmicity and conduction more highly developed than the rest of the heart. (12 Dec 1998) |
| saltatory conduction | A method of neuronal transmission in vertebrate nerves, where only specialised nodes of Ranvier participate in excitation. This reduces the capacitance of the neuron, allowing much faster transmission. See: myelin, Schwann cells. (18 Nov 1997) |
| Purkinje conduction | <neurology, physiology> Conduction of the cardiac impulse through the Purkinje system. (05 Mar 2000) |
| H-R conduction time | Conduction of the cardiac impulse through the ventricular myocardium, represented by the QRS complex in the electrocardiogram. H-R conduction time is from the onset of the first high frequency component of the His bundle electrogram to the onset of the QRS complex of the surface electrocardiogram (normally 43 ± 12 msec); H-V conduction time is from the onset of the first high frequency component of the His bundle electrogram to the onset of the ventricular electrogram (normally approximates the H-R interval but may be a little shorter). Synonym: ventricular conduction. (05 Mar 2000) |
| H-V conduction time | Conduction of the cardiac impulse through the ventricular myocardium, represented by the QRS complex in the electrocardiogram. H-R conduction time is from the onset of the first high frequency component of the His bundle electrogram to the onset of the QRS complex of the surface electrocardiogram (normally 43 ± 12 msec); H-V conduction time is from the onset of the first high frequency component of the His bundle electrogram to the onset of the ventricular electrogram (normally approximates the H-R interval but may be a little shorter). Synonym: ventricular conduction. (05 Mar 2000) |