| PRR | proton relaxation rate; pulse repetition rate |
|---|---|
| PSC | patient services coordination; Porter-Silber chromogen; posterior subcapsular cataract; primary scle... |
| PSP | pancreatic spasmolytic peptide; paralytic shellfish poisoning; parathyroid secretory protein; period... |
| PT | pain threshold; parathormone; parathyroid; paroxysmal tachycardia; part time; patient; pericardial t... |
| PTM | posterior trabecular meshwork; posttransfusion mononucleosis; post-traumatic meningitis; prothymosin... |
| central placenta previa | Placenta previa in which the placenta entirely covers the internal os of the cervix. Synonym: central placenta previa, total placenta previa. (05 Mar 2000) |
|---|---|
| central pneumonia | A form of pneumonia in which exudation is confined for a time to the central portion of a lobe or the hilar region. Synonym: core pneumonia. (05 Mar 2000) |
| central pontine myelinolysis | <neurology> A condition characterised by damage to the myelin (sheath) layer of nerve cells in the pons (brainstem). The destruction of myelin inhibits the conduction of a nerve impulse along a nerve cell. The most common cause for exacerbating this condition is a rapid correction of hyponatraemia (low blood sodium level). Some conditions such as Wernicke-Korsakoff syndrome and alcoholism can predispose to loss of myelin. Symptoms can include weakness, double vision, muscle spasms, speech difficulty, delirium, sleepiness, hallucinations, tremors and uncontrolled eye movements. An MRI scan of the brain can demonstrate the abnormality. A more slow controlled correction of serum sodium levels is necessary in these patients. There is no definitive treatment for the underlying disorder. (12 Jan 1998) |
| central Recklinghausen's disease type II | type 1 neurofibromatosis |
| central retinal artery occlusion | <ophthalmology> The sudden blockage of the retinal artery with a blood clot that commonly leads to a painless but irreversible blindness in that eye. (12 Jan 1998) |
| central retinal fovea | A depression in the centre of the macula retinae containing only cones and lacking blood vessels. Synonym: fovea centralis retinae, central pit. (05 Mar 2000) |
| central retinal vein occlusion | <ophthalmology> The sudden blockage of the retinal vein with blood clot that commonly leads to a painless irreversible blindness in that eye. (12 Jan 1998) |
| central scotoma | A scotoma involving the fixation point. (05 Mar 2000) |
| central serous choroidopathy | Detachment of the sensory retina induced by decreased adhesion between cells of the retinal pigment epithelium which permits plasma from the choriocapillaris to enter subretinal space. Synonym: central angiospastic retinopathy, central serous retinopathy. (05 Mar 2000) |
| central serous retinopathy | Detachment of the sensory retina induced by decreased adhesion between cells of the retinal pigment epithelium which permits plasma from the choriocapillaris to enter subretinal space. Synonym: central angiospastic retinopathy, central serous retinopathy. (05 Mar 2000) |
| central sleep apnoea | <neurology> A form of sleep apnoea which from the lack of neurologic stimulation to breathe. (12 Jan 1998) |
| central spindle | A central group of microtubules (continuous fibres) that course uninterrupted, between the asters, in contrast to the microtubules attached to the individual chromosomes (s. Fibres). (05 Mar 2000) |
| central stop | <microscopy> An opaque disk placed in the ring carrier or diaphragm carrier of the substage apparatus. It excludes the central rays and is used for dark field work at low magnification. Variable stops can be contracted or expanded as desired. (05 Aug 1998) |
| central sulcal artery | <anatomy, artery> A branch of the terminal part of the middle cerebral artery distributed to the cortex on either side of the central sulcus. Synonym: arteria sulci centralis, artery of central sulcus, central artery, Rolandic artery. (05 Mar 2000) |
| central sulcus | A double-S-shaped fissure extending obliquely upward and backward on the lateral surface of each cerebral hemisphere at the boundary between frontal and parietal lobes. Synonym: sulcus centralis, fissure of Rolando. (05 Mar 2000) |