| haemolytic jaundice | <haematology> Haemolytic jaundice is a type of jaundice, where the skin takes on a yellowish hue, which occurs when red blood cells have been destroyed (by haemolysis). (09 Oct 1997) |
|---|---|
| haemolytic plaque assay | <investigation> A haemolytic plaque assay is a lab technique used to show that certain antibodies are secreted by antibody-making cells when these cells are mixed with red blood cells. The mixture is spread onto a plate of agar, if a plaque appears, it means that the red blood cells have been destroyed (by haemolysis) by the antibodies. (09 Oct 1997) |
| haemolytic streptococci | Those that produce active haemolysins (O and S) which cause a zone of clear haemolysis on the blood agar medium in the area of the colony; beta-haemolytic streptococci are divided into groups (A to O) on the basis of cell wall C carbohydrate (see Lancefield classification); Group A (in the strains pathogenic for man) comprises more than 50 types (designated by Arabic numerals) determined by cell wall M protein, which seems to be associated closely with virulence and is produced chiefly by strains with matt or mucoid colonies, in contrast to nonvirulent, glossy colony-producing strains; other surface protein antigens such as R and T (T substance), and the nucleoprotein fraction (P substance) seem to be of less importance. The more than 20 extracellular substances elaborated by strains of beta-haemolytic streptococci include erythrogenic toxin (elaborated only by lysogenic strains), deoxyribonuclease (streptodornase), haemolysins (streptolysins O and S), hyaluronidase, and streptokinase. Synonym: haemolytic streptococci. (05 Mar 2000) |
| haemolytic system | <haematology> A haemolytic system is composed of red blood cells covered with antibodies which are genetically identical to the surface proteins (antigens) of the red blood cells. It is used to measure how much complement is left after a round of complement fixation. (09 Oct 1997) |
| haemolytic unit | The smallest quantity (highest dilution) of inactivated immune serum (haemolysin) that will sensitise the standard suspension of erythrocytes so that the standard complement will cause complete haemolysis. Synonym: amboceptor unit. (05 Mar 2000) |
| haemolytic uraemic syndrome | <haematology, syndrome> A pathologic condition with involves the rupture (haemolysis) of red blood cells, subsequent anaemia, low platelet count and kidney failure. It is a syndrome of haemolytic anaemia, thrombocytopenia, and acute renal failure, with pathological finding of thrombotic microangiopathy in kidney and renal cortical necrosis. See: haemolytic anaemia. (12 Dec 1998) |
| disease, haemolytic, of the newborn | Abnormal breakup of red blood cells in the foetus or newborn. (12 Dec 1998) |
| unstable haemoglobin haemolytic anaemia | A congenital haemolytic anaemia, due to autosomal inheritance of one of many unstable haemoglobins. The anaemia is of variable severity and characterised by the presence in vivo or in vitro of Heinz bodies. (05 Mar 2000) |