Argon Plasma Coagulation: From 1 Different Sources
an endoscopic procedure used predominantly to control bleeding in the gastrointestinal tract. secondary to angiodysplasia and bleeding following polypectomy. Occasionally it is used in the debulking of tumours not amenable to surgery. An intermittent stream of argon gas is delivered through a catheter in the endoscope and ionized by a monopolar electrical current producing a controlled release of thermal energy. This causes coagulation in the adjacent tissues.
The name applied to the straw-coloured ?uid portion of the BLOOD composed of a solution of various inorganic salts of sodium, potassium, calcium, etc., as well as SERUM and ?brinogen, the material which produces clotting (see COAGULATION). When the plasma is clotted, the thinner ?uid separating from the clot is the serum.... plasma
These are cells that produce ANTIBODIES and occur in bone-forming tissue as well as the lining of the gastrointestinal tract and the lungs. The cells develop in LYMPH NODES, SPLEEN and BONE MARROW when T-lymphocytes (see IMMUNITY) are stimulated by antigens (see ANTIGEN) to produce the precursor cells from which plasma cells originate.... plasma cells
(DIC) A type of bleeding disorder in which abnormal clotting leads to depletion of coagulation factors in the blood; the consequence may be severe spontaneous bleeding.... disseminated intravascular coagulation
The main mechanism by which blood clots are formed, involving a complex series of reactions in the blood plasma (see blood clotting).... coagulation, blood
Proteins present in blood plasma, including albumin, blood clotting proteins, and immunoglobulins.... plasma proteins
a type of *laser that utilizes argon gas to produce a beam of intense light, used especially in eye surgery to treat disease of the retina (e.g. diabetic retinopathy) or glaucoma (as in argon laser *trabeculoplasty). See also photocoagulation.... argon laser
... blood plasma see plasma.
(blood clotting) the process whereby blood is converted from a liquid to a solid state. The process may be initiated by contact of blood with a foreign surface (intrinsic system) or with damaged tissue (extrinsic system). These systems involve the interaction of a variety of substances (*coagulation factors) and lead to the production of the enzyme thrombin, which converts the soluble blood protein *fibrinogen to the insoluble protein *fibrin, forming the blood clot. Finally, fibrin is broken down by the action of *plasmin. Anticoagulants and tissue plasminogen activators act by inhibiting or activating various pathways in this cascade (see illustration). Blood coagulation is an essential mechanism for the arrest of bleeding (*haemostasis). See also platelet activation.... blood coagulation
(clotting factors) a group of substances present in blood plasma that, under certain circumstances, undergo a series of chemical reactions leading to the conversion of blood from a liquid to a solid state (see blood coagulation). Although they have specific names, most coagulation factors are referred to by an agreed set of Roman numerals (e.g. *Factor VIII, *Factor IX). Lack of any of these factors in the blood results in the inability of the blood to clot. See also haemophilia.... coagulation factors
(clotting time) the time taken for blood or blood plasma to coagulate (see blood coagulation). When measured under controlled conditions and using appropriate techniques, coagulation times may be used to test the function of the various stages of the blood coagulation process.... coagulation time
see cervical intraepithelial neoplasia.... cold coagulation
a type of *electrocoagulation used to arrest haemorrhage or destroy abnormal tissue. A stream of inert gas, such as argon or helium, is ionized, thereby carrying electrical energy to adjacent tissue; there is no physical contact between the plasma coagulation apparatus and the tissue.... plasma coagulation