| Waldeyer's throat ring | The broken ring of lymphoid tissue, formed of the lingual, faucial, and pharyngeal tonsils. Synonym: Bickel's ring, tonsillar ring, Waldeyer's throat ring. (05 Mar 2000) |
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| sore throat | A condition characterised by pain or discomfort on swallowing; it may be due to any of a variety of inflammations of the tonsils, pharynx, or larynx. (05 Mar 2000) |
| strep throat | An infection caused by a type of bacteria called streptococcus, which can lead to serious complications if not adequately treated. (12 Dec 1998) |
| throat | <botany> Refers to the top of a corolla tube, where the tube joins the lobes. (09 Oct 1997) |
| alpha-streptococci | Streptococci that form a green variety of reduced haemoglobin in the area of the colony on a blood agar medium. (05 Mar 2000) |
| beta-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) |
| group A streptococci | A common bacteria that is the cause of strep throat, scarlet fever, impetigo, cellulitis-erysipelas, rheumatic fever, acute glomerular nephritis, endocarditis, and group A streptococcal necrotizing fasciitis. The prototype is Streptococcus pyogenes. (05 Mar 2000) |
| group B streptococci | A leading cause of a form of neonatal sepsis that has a 10-20% mortality rate and leaves a large number of survivors with brain damage. Also a leading cause of meningitis. (05 Mar 2000) |
| 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) |
| streptococci | <bacteria, organism> A genus of bacteria that are gram-positive cocci, often occurring in chains of varying length. Some pathogenic species produce exotoxins. In man, streptococcal species are responsible for numerous infections such as scarlet fever, tonsillitis, erysipelas (skin infection), endocarditis, rheumatic fever, glomerulonephritis, impetigo, pneumonia, meningitis, pharyngitis, lymphadenitis and wound infections. Streptococcus pneumoniae is the main culprit in lobar and bronchopneumonia. Streptococci have anti-phagocytic components (hyaluronic acid rich capsule and M protein) and release various toxins streptolysins O and s, erythrogenic toxin) and enzymes streptokinase, streptodornase, hyaluronidase and proteinase. Haemolytic streptococci (viridans streptococci) produce limited haemolysis on blood agar, include Streptococcus mutans, Streptococcus salivarius and Streptococcus pneumoniae. Beta haemolytic streptococci, of which Streptococcus pyogenes is the only species, though there are many serotypes, produce a broad zone of almost complete haemolysis on blood agar as a result of streptolysin O and S release. Alpha streptococci are nonhaemolytic (e.g. Streptococcus faecalis). (30 Sep 1997) |