| set (psychology) | Readiness to think or respond in a predetermined way when confronted with a problem or stimulus situation. (12 Dec 1998) |
|---|---|
| set-up | 1. The arrangement of teeth on a trial denture base. 2. A procedure in dental case analysis involving cutting off and repositioning of teeth in the desired positions on a plaster cast. (05 Mar 2000) |
| ear, low-set | A minor anomaly involving an ear situated down below its normal location. Technically, the ear is low-set when the helix (of the ear) meets the cranium at a level below that of a horizontal plane through both inner canthi (the inside corners of the eyes). The presence of 2 or more minor anomalies in a child increases the probability that the child has a major malformation. (12 Dec 1998) |
| first-set rejection | Allograft transplantation between two organisms not previously sensitised to the graft tissue. Necrosis of the graft usually occurs within 10 days of transplantation. (05 Mar 2000) |
| learning set | A readiness or predisposition to learn developed from previous learning experiences, as when an organism learns to solve each successive problem (of equal or increasing difficulty) in fewer trials. (05 Mar 2000) |
| low-set ear | An ear positionned below its normal location. Classified as a minor anomaly. Technically, the ear is low-set when the helix (of the ear) meets the cranium at a level below that of a horizontal plane through both inner canthi (the inside corners of the eyes). The presence of 2 or more minor anomalies in a child increases the probability that the child has a major malformation. (12 Dec 1998) |
| acquired platelet function defect | <haematology> Platelet function can be affected by a number of different disease processes including polycythaemia vera, leukaemia, myelofibrosis, renal failure, multiple myeloma and some medications (for example penicillins, salicylates, phenothiazines). Disturbed blood clotting can be manifested by: easy bruising, bleeding gums, nosebleeds, abnormal vaginal bleeding, rectal bleeding, skin rash, vomiting blood, coughing up blood or blood in the urine. A measure of bleeding time and coagulation profile will be part of the evaluation. (29 Dec 1997) |
| antigens, human platelet | Human alloantigens expressed only on platelets, specifically on platelet membrane glycoproteins. These platelet-specific antigens are immunogenic and can result in pathological reactions to transfusion therapy. (12 Dec 1998) |
| anti-platelet agents | Medications that, like aspirin, reduce the tendency of platelets in the blood to clump and clot. (12 Dec 1998) |
| receptors, platelet-derived growth factor | Specific molecular sites or structures on cell membranes that react with platelet-derived growth factor, its analogs, or antagonists, to elicit or to inhibit the specific response of the cell to this factor. Pdgf binds with different affinities and specificities to two structurally related receptors, the alpha-receptor and the beta-receptor. Both of these receptors are transmembrane proteins with an intracellular, ligand-stimulatable protein kinase domain. (12 Dec 1998) |
| medication, anti-platelet | Platelet-blocking drugs. Drugs that, like aspirin, reduce the tendency of platelets in the blood to clump and clot. (12 Dec 1998) |
| platelet | <haematology> A discoid cell (3m diameter) found in large numbers in blood, important for blood coagulation and for haemostasis by repairing breaches (small breaks) in the walls of blood vessels. Platelet _ granules contain lysosomal enzymes, dense granules contain ADP (a potent platelet aggregating factor) and serotonin (a vasoactive amine). They also release platelet-derived growth factor which presumably contributes to later repair processes by stimulating fibroblast proliferation. Synonym: thrombocytes. (09 Oct 1997) |
| platelet-activating factor | <cytokine> Potent phospholipid activator and mediator of many leucocyte functions, including platelet aggregation, inflammation, and anaphylaxis. It is produced in response to specific stimuli by a variety of cell types, including neutrophils, basophils, platelets, and endothelial cells. Several molecular species of platelet-activating factor have been identified which vary in the length of the O-alkyl side chain. It is an important mediator of bronchoconstriction. Synonym: platelet-aggregating factor. Acronym: PAF (20 Sep 2002) |
| platelet activation | A series of progressive, overlapping events triggered by exposure of the platelets to subendothelial tissue. These events include shape change, adhesiveness, aggregation, and release reactions. When carried through to completion, these events lead to the formation of a stable haemostatic plug. (12 Dec 1998) |
| platelet actomyosin | The contractile protein of platelets, responsible for clot retraction, platelet aggregation, and release of ADP and other biologic amines essential to platelet function. Synonym: thrombosthenin. (05 Mar 2000) |