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NCBI/NLM/NIH Entrez Glossary

NCBI/NLM/NIH Glossary


acanthamoeba
A genus of free-living soil amoebae that produces no flagellate stage. Its organisms are pathogens for several infections in humans and have been found in the eye, bone, brain, and respiratory tract

acanthamoeba keratitis
Infection of the cornea by an ameboid protozoan which may cause corneal ulceration leading to blindness

acquired immunodeficiency syndrome
An acquired defect of cellular immunity associated with infection by the human immunodeficiency virus (HIV), a CD4-positive T-lymphocyte count under 200 cells/microliter or less than 14% of total lymphocytes, and increased susceptibility to opportunistic infections and malignant neoplasms. Clinical manifestations also include emaciation (wasting) and dementia. These elements reflect criteria for AIDS as defined by the CDC in 1993

adenosine diphosphate glucose
Serves as the glycosyl donor for formation of bacterial glycogen, amylose in green algae, and amylopectin in higher plants

adenoviridae
A family of non-enveloped viruses infecting mammals (MASTADENOVIRUS) and birds (AVIADENOVIRUS). Infections may be asymptomatic or result in a variety of diseases

adenoviridae infections
Virus diseases caused by the ADENOVIRIDAE

aeromonas hydrophila
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria that may be pathogenic for frogs, fish, and mammals, including man. In humans, cellulitis and diarrhea can result from infection with this organism

aflatoxin b1
6aR-cis-2,3,6aalpha,9aalpha-Tetrahydro-4-methoxycyclopenta(c)furo(3\',2\':4,5)furo(2,3-h)(1)benzopyran-1,11-dione. The compound is a potent hepatotoxic and hepatocarcinogenic mycotoxin produced by the Aspergillus flavus group of fungi. It is also mutagenic, teratogenic, and causes immunosuppression in animals. It is found as a contaminant in peanuts, cottonseed meal, corn, and other grains. The mycotoxin requires epoxidation to aflatoxin B1-2,3-oxide for activation. Microsomal monooxygenases biotransform the toxin to the less toxic metabolites aflatoxin M1 and Q1

aflatoxins
A group of closely related toxic metabolites that are designated mycotoxins. They are produced by Aspergillus flavus and A. parasiticus. Members of the group include AFLATOXIN B1, aflatoxin B2, aflatoxin G1, aflatoxin G2, AFLATOXIN M1, and aflatoxin M2

aids-related complex
A prodromal phase of infection with the human immunodeficiency virus (HIV). Laboratory criteria separating AIDS-related complex (ARC) from AIDS include elevated or hyperactive B-cell humoral immune responses, compared to depressed or normal antibody reactivity in AIDS; follicular or mixed hyperplasia in ARC lymph nodes, leading to lymphocyte degeneration and depletion more typical of AIDS; evolving succession of histopathological lesions such as localization of Kaposi\'s sarcoma, signaling the transition to the full-blown AIDS

amanitins
A group of very potent toxins from Amanita species which cause lethal liver and kidney damage and inhibit some RNA synthesis

amebiasis
Infection with any of various amebae. It is an asymptomatic carrier state in most individuals, but diseases ranging from chronic, mild diarrhea to fulminant dysentery may occur

amphotericin b
Polyene antifungal antibiotic produced by Streptomyces nodosus obtained from soil of the Orinoco river region of Venezuela

ampicillin
6-((Aminophenylacetyl)amino)-3,3-dimethyl-7-oxo-4-thia-1- azabicyclo(3.2.0)heptane-2-carboxylic acid. Semi-synthetic derivative of penicillin that functions as an orally active broad-spectrum antibiotic

ampicillin resistance
Nonsusceptibility of a microbe to the action of ampicillin, a penicillin derivative that interferes with cell wall synthesis

anaphylatoxins
The family of peptides C3a, C4a, C5a, and C5a des-arginine produced in the serum during complement activation. They produce smooth muscle contraction, mast cell histamine release, affect platelet aggregation, and act as mediators of the local inflammatory process. The order of anaphylatoxin activity from strongest to weakest is C5a, C3a, C4a, and C5a des-arginine. The latter is the so-called "classical" anaphylatoxin but shows no spasmogenic activity though it contains some chemotactic ability

anemia hemolytic
Anemia due to decreased life span of erythrocytes

antacids
Substances that counteract or neutralize acidity. They are used mainly for the treatment of gastrointestinal irritation or ulcers

antinematodal agents
Substances used in the treatment or control of nematode infestations. They are used also in veterinary practice

appendicitis
Acute inflammation of the vermiform appendix

astroviruses
Small (approximately 28nm diameter) circular viruses sometimes showing a star-shaped surface configuration, found in stools of vertebrates with infantile gastroenteritis. The taxonomic status is uncertain though a relationship to Picornaviridae has been suggested

atropine
A toxic alkaloid, originally from Atropa belladonna, but found in other plants, mainly Solanaceae. It is used as an antimuscarinic agent for relaxation of smooth muscle, to increase heart rate, as an anesthetic premedication, as an antispasmotic, in anticholinesterase poisoning, in aspiration pneumonitis, in bronchial disorders, or to dilate the pupil, among other uses

atropine derivatives
Analogs and derivatives of atropine

bacillus anthracis
A species of bacteria that causes ANTHRAX in humans and animals

bacillus subtilis
A species of gram-positive bacteria that is a common soil and water saprophyte

bacillus thuringiensis
A species of gram-positive bacteria which may be pathogenic for certain insects. It is used for the biological control of the Gypsy moth

bacteremia
The presence of viable bacteria circulating in the blood. Fever, chills, tachycardia, and tachypnea are common acute manifestations of bacteremia. The majority of cases are seen in already hospitalized patients, most of whom have underlying diseases or procedures which render their bloodstreams susceptible to invasion

bacterial toxins
Toxic substances formed in or elaborated by bacteria; they are usually proteins with high molecular weight and antigenicity; some are used as antibiotics and some to skin test for the presence of or susceptibility to certain diseases

botulinum toxins
Toxins produced by Clostridium botulinum. There are at least seven different substances, most being proteins. They have neuro-, entero-, and hemotoxic properties, are immunogenic, and include the most potent poisons known. The most commonly used apparently blocks release of acetylcholine at cholinergic synapses

botulism
A disease caused by potent protein neurotoxins produced by CLOSTRIDIUM BOTULINUM. Characteristics include abdominal pain, vomiting, motor disturbances, and visual difficulties. The Centers for Disease Control and Prevention classify botulism into four types: (1) food-borne; (2) infant; (3) wound; and (4) indeterminate

bungarotoxins
Neurotoxic proteins from the venom of the banded or Formosan krait (Bungarus multicinctus, an elapid snake). alpha-Bungarotoxin blocks nicotinic acetylcholine receptors and has been used to isolate and study them; beta- and gamma-bungarotoxins act presynaptically causing acetylcholine release and depletion. Both alpha and beta forms have been characterized, the alpha being similar to the large, long or Type II neurotoxins from other elapid venoms

calicivirus
A genus in the family Caliciviridae containing many species including feline calicivirus (CALICIVIRUS, FELINE), VESICULAR EXANTHEMA OF SWINE VIRUS, and San Miguel sea lion viruses

campylobacter
A genus of bacteria found in the reproductive organs, intestinal tract, and oral cavity of animals and man. Some species are pathogenic

campylobacter coli
A species of gram-negative, rod-shaped bacteria isolated from the intestinal tract of swine, poultry, and man. It may be pathogenic

campylobacter fetus
A species of bacteria present in man and many kinds of animals and birds, often causing infertility and/or abortion

campylobacter infections
Infections with bacteria of the genus CAMPYLOBACTER

campylobacter jejuni
A species of bacteria that resemble small tightly coiled spirals. Its organisms are known to cause abortion in sheep and fever and enteritis in man and may be associated with enteric diseases of calves, lambs, and other animals

cd4-positive t-lymphocytes
A critical subpopulation of regulatory T-lymphocytes involved in the induction of most immunological functions. The HIV virus has selective tropism for the T4 cell which expresses the CD4 phenotypic marker, a receptor for HIV. In fact, the key element in the profound immunosuppression seen in HIV infection is the depletion of this subset of T-lymphocytes, which includes both the helper-inducer (T-LYMPHOCYTES, HELPER-INDUCER) and suppressor-inducer (T-LYMPHOCYTES, SUPPRESSOR-INDUCER) T-cells

cd8-positive t-lymphocytes
A critical subpopulation of regulatory T-lymphocytes involved in MHC Class I-restricted interactions. They are include both cytotoxic T-lymphocytes (T-LYMPHOCYTES, CYTOTOXIC) and suppressor T-lymphocytes (T-LYMPHOCYTES, SUPPRESSOR-EFFECTOR)

chlortetracycline
(4S-(4 alpha,4a alpha,5a alpha,6 beta,12a alpha))-7-Chloro-4-dimethylamino-1,4,4a,5,5a,6,11,12,12a-octahydro-3,6,10,12,12a-pentahydroxy-6-methyl-1,11-dioxo-2-naphthacenecarboxamide. An antibiotic substance isolated from the substrate of Streptomyces aureofaciens and used as an antibacterial and antiprotozoal agent

cholecystitis
Inflammation of the gallbladder

cholera
An acute diarrheal disease endemic in India and Southeast Asia whose causative agent is VIBRIO CHOLERAE. This condition can lead to severe dehydration in a matter of hours unless quickly treated

cholera toxin
The exotoxin from Vibrio cholerae. It is a protein that consists of two major components, the heavy (H) or A peptide and the light (L) or B peptide or choleragenoid which binds the whole protein to cell membranes, is nontoxic, but immunogenic. The A fragment causes cholera, probably due to the activation of adenylate cyclase; it consists of two polypeptide fragments

cimetidine
Blocker of histamine H2 receptors that decreases gastric acid secretion and reduces pepsin output. It is used to treat gastrointestinal ulcers

citrobacter freundii
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria found in man and other animals including mammals, birds, reptiles, and amphibians. Its organisms have also been isolated from soil and water as well as from clinical specimens such as urine, throat, sputum, blood, and wound swabs as an opportunistic pathogen

clostridium perfringens
The most common etiologic agent of GAS GANGRENE. It is differentiable into several distinct types based on the distribution of twelve different toxins

colitis ulcerative
Inflammatory disease of unknown cause which involves the mucosa of the colon. Onset may be acute and fulminant, and its course often continues chronically in an intermittent or continuous form. Diarrhea is a common symptom and bleeding an almost constant concomitant symptom

coma
A profound state of unconsciousness. It includes "stupor" from which the patient can be partially roused, as well as complete unconsciousness in which there is no response to sensory stimuli, even at the reflex level

convulsions
Seizures manifested by discontinuous involuntary skeletal muscular contractions, either brief contractions repeated at short intervals or longer ones interrupted by intervals of muscular relaxation

convulsions febrile
Seizures occurring in young children during febrile episodes due to a low convulsive threshold. The convulsions are usually a self-limiting disorder after the age of 5 years

crohn disease
Gastrointestinal disorder characterized by chronic inflammatory infiltrates, fibrosis affecting all layers of the serosa, and development of noncaseating granulomas. The most common site of involvement is the terminal ileum with the colon as the second most common

cryptosporidiosis
Parasitic intestinal infection with severe diarrhea caused by a protozoan, CRYPTOSPORIDIUM. It occurs in both animals and humans

cytotoxins
Substances elaborated by microorganisms, plants or animals that are specifically toxic to individual cells; they may be involved in immunity or may be contained in venoms

dermotoxins
Specific substances elaborated by plants, microorganisms or animals that cause damage to the skin; they may be proteins or other specific factors or substances; constituents of spider, jellyfish or other venoms cause dermonecrosis and certain bacteria synthesize dermolytic agents

diabetes mellitus
A heterogeneous group of disorders that share glucose intolerance in common

dinoflagellida
Protozoans of the class PHYTOMASTIGOPHORA, found mainly in the oceans. They are characterized by the presence of transverse and longitudinal flagella which propel the organisms in a rotating manner through the water

endotoxins
Toxins closely associated with the living cytoplasm or cell wall of certain microorganisms, which do not readily diffuse into the culture medium, but are released upon lysis of the cells

enterobacteriaceae
A family of gram-negative, facultatively anaerobic, rod-shaped bacteria that do not form endospores. Its organisms are distributed worldwide with some being saprophytes and others being plant and animal parasites. Many species are of considerable economic importance due to their pathogenic effects on agriculture and livestock

enterobacteriaceae infections
Infections with bacteria of the family ENTEROBACTERIACEAE

enterotoxins
Substances that are toxic to the intestinal tract causing vomiting, diarrhea, etc.; most common enterotoxins are produced by bacteria

enzyme-linked immunosorbent assay
An immunoassay utilizing an antibody labeled with an enzyme marker such as horseradish peroxidase. While either the enzyme or the antibody is bound to an immunosorbent substrate, they both retain their biologic activity; the change in enzyme activity as a result of the enzyme-antibody-antigen reaction is proportional to the concentration of the antigen and can be measured spectrophotometrically or with the naked eye. Many variations of the method have been developed

eosinophils
Granular leukocytes with a nucleus that usually has two lobes connected by a slender thread of chromatin, and cytoplasm containing coarse, round granules that are uniform in size and stainable by eosin

erabutoxins
Toxins isolated from the venom of Laticauda semifasciata, a sea snake (Hydrophid); immunogenic, basic polypeptides of 62 amino acids, folded by four disulfide bonds, block neuromuscular end-plates irreversibly, thus causing paralysis and severe muscle damage; they are similar to Elapid neurotoxins

erythromycin
Antibiotic substance produced by Streptomyces erythreus found first in a soil sample from the Philippines. Three erythromycins are produced during fermentation - A, B, and C. Erythromycin A is the major component

exotoxins
Toxins produced, especially by bacterial or fungal cells, and released into the culture medium or environment

gastric acid
Hydrochloric acid present in gastric juice

gastric acidity determination
Gastric analysis for determination of free acid or total acid

giardiasis
An infection of the small intestine caused by the flagellated protozoan GIARDIA LAMBLIA. It is spread via contaminated food and water and by direct person-to-person contact

glucose
D-Glucose. A primary source of energy for living organisms. It is naturally occurring and is found in fruits and other parts of plants in its free state. It is used therapeutically in fluid and nutrient replacement

glucose-6-phosphatase
An enzyme that catalyzes the conversion of D-glucose 6-phosphate and water to D-glucose and orthophosphate. EC 3.1.3.9

glucose dehydrogenases
D-Glucose:1-oxidoreductases. Catalyzes the oxidation of D-glucose to D-glucono-gamma-lactone and reduced acceptor. Any acceptor except molecular oxygen is permitted. Includes EC 1.1.1.47; EC 1.1.1.118; EC 1.1.1.119 and EC 1.1.99.10

gram-negative bacteria
Bacteria which lose crystal violet stain but are stained pink when treated by Gram\'s method

gram-negative bacterial infections
Infections caused by bacteria that show up as pink (negative) when treated by the gram-staining method

gram-positive bacteria
Bacteria which retain the crystal violet stain when treated by Gram\'s method

gram-positive bacterial infections
Infections caused by bacteria that retain the crystal violet stain (positive) when treated by the gram-staining method

gram-positive cocci
Coccus-shaped bacteria that retain the crystal violet stain when treated by Gram\'s method

gram-positive endospore-forming bacteria
Bacteria that form endospores and are gram-positive. Representative genera include BACILLUS, CLOSTRIDIUM, MICROMONOSPORA, SACCHAROPOLYSPORA, and STREPTOMYCES

gram-positive rods
A large group of rod-shaped bacteria that retains the crystal violet stain when treated by Gram\'s method

hemagglutinins
Agents that cause agglutination of red blood cells. They include antibodies, blood group antigens, lectins, autoimmune factors, bacterial, viral, or parasitic blood agglutinins, etc

hemolytic-uremic syndrome
Syndrome of hemolytic anemia, thrombocytopenia, and acute renal failure, with pathological finding of thrombotic microangiopathy in kidney and renal cortical necrosis

hepatitis a
Hepatitis caused by HEPATOVIRUS. It can be transmitted through fecal contamination of food or water

hepatitis a virus
A genus of PICORNAVIRIDAE causing infectious hepatitis naturally in humans and experimentally in other primates. It is transmitted through fecal contamination of food or water

hepatitis antibodies
Immunoglobulins raised by any form of viral hepatitis; some of these antibodies are used to diagnose the specific kind of hepatitis

hepatitis e virus
A positive-stranded RNA virus causing enterically-transmitted non-A, non-B hepatitis (HEPATITIS E). The morphological and physiochemical properties suggest that it is a member of the calicivirus family (CALICIVIRIDAE)

histamine
The procedure of assaying for histamine concentration

hla-b27 antigen
Human histocompatibility (HLA) surface antigen encoded by the B locus on chromosome 6. It is strongly associated with acute anterior uveitis, ankylosing spondylitis, and Reiter\'s disease

hla-b7 antigen
Human histocompatibility (HLA) surface antigen encoded by the B locus on chromosome 6. There is a weak association between the presence of the HLA-B7 antigen and the diseases of narcolepsy and idiopathic hemochromatosis. HLA-B7 is in linkage disequilibrium with HLA-A3 and HLA-DR2

ibotenic acid
alpha-Amino-3-hydroxy-5-isoxazoleacetic acid. Neurotoxic isoxazole substance found in Amanita muscaria and A. pantherina. It causes motor depression, ataxia, and changes in mood, perceptions and feelings, and is a potent excitatory amino acid agonist

immunocompromised host
A human or animal whose immunologic mechanism is deficient because of an immunodeficiency disorder or other disease or as the result of the administration of immunosuppressive drugs or radiation

ketoconazole
1-Acetyl-4-[4-[(2-(2,4-dichlorophenyl)-2- (1H-imidazol-1-ylmethyl)-1,3-dioxolan-4-yl)methoxy] -phenyl]-cis-piperazine. Broad spectrum antifungal agent used for long periods at high doses, especially in immunosuppressed patients

lectins
Protein or glycoprotein substances, usually of plant origin, that bind to sugar moieties in cell walls or membranes and thereby change the physiology of the membrane to cause agglutination, mitosis, or other biochemical changes in the cell

leukocytes
White blood cells. These include granular leukocytes (BASOPHILS, EOSINOPHILS, and NEUTROPHILS) as well as non-granular leukocytes (LYMPHOCYTES and MONOCYTES)

listeria
A genus of bacteria which may be found in the feces of animals and man, on vegetation, and in silage. Its species are parasitic on cold-blooded and warm-blooded animals, including man

listeria infections
Infections with bacteria of the genus LISTERIA

listeria monocytogenes
A species of gram-positive, rod-shaped bacteria widely distributed in nature. It has been isolated from sewage, soil, silage, and from feces of healthy animals and man. Infection with this bacterium leads to encephalitis, meningitis, endocarditis, and abortion

liver cirrhosis
Liver disease in which the normal microcirculation, the gross vascular anatomy, and the hepatic architecture have been variably destroyed and altered with fibrous septa surrounding regenerated or regenerating parenchymal nodules

marine toxins
Toxic or poisonous substances elaborated by marine flora or fauna. They include also specific, characterized poisons or toxins for which there is no more specific heading, like those from poisonous fishes. Clupeotoxin, pahutoxin, prymnesin, scombrotoxin go here

mebendazole
Methyl-5-benzoyl-2-benzimidazolecarbamate. A nematocide in humans and animals. It acts by interfering with the carbohydrate metabolism and associated energy production of the parasite

monocytes
Large, phagocytic mononuclear leukocytes produced in the vertebrate bone marrow and released into the blood; contain a large, oval or somewhat indented nucleus surrounded by voluminous cytoplasm and numerous organelles

muscarine
2-Methyl-3-hydroxy-5-(aminomethyl)tetrahydrofuran, trimethylammonium salt. A toxic alkaloid found in Amanita muscaria (fly fungus) and other fungi of the Inocybe species. It is the first parasympathomimetic substance ever studied and causes profound parasympathetic activation that may end in convulsions and death. The specific antidote is atropine

muscimol
5-(Aminomethyl)-3-isoxazolol. Neurotoxic isoxazole isolated from Amanita muscaria and A. phalloides and also obtained by decarboxylation of IBOTENIC ACID. It is a potent agonist at GABA-A receptors and is used mainly as an experimental tool in animal and tissue studies

naegleria fowleri
A species of parasitic protozoa having both an ameboid and flagellate stage in its life cycle. Infection with this pathogen produces primary amebic meningoencephalitis

nematoda
A class of unsegmented helminths with fundamental bilateral symmetry and secondary triradiate symmetry of the oral and esophageal structures. Many species are parasites

ochratoxins
Toxins produced by Aspergillus ochraceus. Occurring widely, ochratoxins have been found as natural contaminants on storage grains, corn, peanuts, cottonseed, and decaying vegetation. They are produced by several other species of Aspergillus as well as by Penicillium viridicatum

oxytetracycline
(4S-(4 alpha,4a alpha,5a alpha,6 beta,12a alpha))-4-(Dimethylamino)-1,4,4a,5,5a,6,11,12a-octahydro-3,5,6,10,12,12a-hexahydroxy-6-methyl-1,11-dioxo-2-naphthacenecarboxamide. An antibiotic substance isolated from the actinomycete Streptomyces rimosus and used in a wide variety of clinical conditions

paratyphoid fever
A prolonged febrile illness commonly caused by serotypes of Salmonella paratyphi. It is similar to typhoid fever but less severe

parvoviridae
A family of very small DNA viruses containing a single linear molecule of single-stranded DNA and consisting of three genera: DENSOVIRUS, DEPENDOVIRUS, and PARVOVIRUS. They infect both vertebrates and invertebrates

parvoviridae infections
Virus infections caused by the PARVOVIRIDAE

penicillin v
(2S-(2 alpha,5 alpha,6 beta)-3,3-Dimethyl-7-oxo-6-((phenoxyacetyl)amino)-4-thia-1- azabicyclo(3.2.0)heptane-2-carboxylic acid. A broad-spectrum penicillin antibiotic used orally in the treatment of mild to moderate infections by susceptible gram-positive organisms

peptic ulcer
Ulcer that occurs in those portions of the alimentary tract which come into contact with gastric juice containing pepsin and acid. It occurs when the amount of acid and pepsin is sufficient to overcome the gastric mucosal barrier

peptic ulcer perforation
Penetration of a peptic ulcer through the stomach wall. May be free, i.e., at a point where the stomach wall faces a real or potential space,, or confined, i.e., at a point where the stomach wall is defended by contiguous or adjacent structures, such as the pancreas

phytohemagglutinins
Mucoproteins isolated from the kidney bean (Phaseolus vulgaris); some of them are mitogenic to lymphocytes, others agglutinate all or certain types of erythrocytes or lymphocytes. They are used mainly in the study of immune mechanisms and in cell culture

phytoplankton
Minute plant organisms which live in practically all natural waters

picornaviridae
A family of small RNA viruses comprising some important pathogens of humans and animals. Transmission usually occurs mechanically. There are five genera: APHTHOVIRUS, CARDIOVIRUS, ENTEROVIRUS, HEPATOVIRUS, and RHINOVIRUS

picornaviridae infections
Virus diseases caused by the PICORNAVIRIDAE

plague
An acute infectious disease caused by YERSINIA PESTIS that affects humans, wild rodents, and their ectoparasites. This condition persists due to its firm entrenchment in sylvatic rodent-flea ecosystems throughout the world. Bubonic plague is the most common form

purpura
A group of disorders characterized by purplish or brownish red discoloration, easily visible through the epidermis, caused by hemorrhage into the tissues

purpura thrombocytopenic
Any form of purpura in which the platelet count is decreased. Many forms are thought to be caused by immunological mechanisms

reiter\'s disease
A triad of nongonococcal urethritis followed by conjunctivitis and arthritis, of unknown etiology

reoviridae
A family of unenveloped RNA viruses with cubic symmetry. The eight genera include ORTHOREOVIRUS, ORBIVIRUS, COLTIVIRUS, ROTAVIRUS, Aquareovirus, Cypovirus, Phytoreovirus, and Fijivirus

reoviridae infections
Infections produced by reoviruses, general or unspecified

reye\'s syndrome
An acute disease in children characterized by vomiting, hepatic injury with fatty vacuolization, central nervous system damage, and hypoglycemia

salmonella food poisoning
Poisoning caused by ingestion of food harboring species of SALMONELLA. Conditions of raising, shipping, slaughtering, and marketing of domestic animals contribute to the spread of this bacterium in the food supply

sanitation
The development and establishment of environmental conditions favorable to the health of the public

saxitoxin
Poison found in certain edible mollusks at certain times; elaborated by Gonyaulax species (Dinoflagellate protozoans) and consumed by mollusks, fishes, etc. without ill effects; it is neurotoxic and causes respiratory paralysis and other effects in mammals, known as paralytic shellfish poisoning

scarlet fever
Infection with group A streptococci that is characterized by tonsillitis and pharyngitis. An erythematous rash is commonly present

shigella
A genus of gram-negative, facultatively anaerobic, rod-shaped bacteria that ferments sugar without gas production. Its organisms are intestinal pathogens of man and other primates and cause bacillary dysentery (DYSENTERY, BACILLARY)

shigella boydii
One of the SHIGELLA species that produces bacillary dysentery (DYSENTERY, BACILLARY)

shigella dysenteriae
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria that is extremely pathogenic and causes severe dysentery. Infection with this organism often leads to ulceration of the intestinal epithelium

shigella flexneri
A bacterium which is one of the etiologic agents of bacillary dysentery (DYSENTERY, BACILLARY) and sometimes of infantile gastroenteritis

shigella sonnei
A lactose-fermenting bacterium causing dysentery

sinoatrial node
The small mass of modified cardiac muscle fibers located at the junction of the superior vena cava and right atrium. Contraction impulses probably start in this node, spread over the atrium and are then transmitted by the atrioventricular bundle to the ventricle

sodium channels
Cell membrane glycoproteins selective for sodium ions. Fast sodium current is associated with the action potential in neural membranes

spores
The reproductive elements of lower organisms, such as protozoa, fungi, and cryptogamic plants

staphylococcal food poisoning
Poisoning by staphylococcal toxins present in contaminated food

tetracycline
(4S-(4 alpha,4a alpha,5a alpha,6 beta,12a alpha))-4-(Dimethylamino)-1,4,4a,5,5a,6,11,12a-octahydro-3,6,10,12,12a-pentahydroxy-6-methyl-1,11-dioxo-2-naphthacenecarboxamide. An antibiotic originally produced by Streptomyces viridifaciens, but used mostly in synthetic form

tetracyclines
Broad-spectrum natural and semisynthetic antibiotics with a naphthacene structure obtained from various Streptomyces species

tetrodotoxin
Octahydro-12-(hydroxymethyl)-2-imino-5,9:7,10a-dimethano- 10aH-(1,3)dioxocino(6,5-a)pyrimidine-4,7,10,11,12-pentol. An aminoperhydroquinazoline poison found mainly in the liver and ovaries of fishes in the order Tetradontiformes (pufferfish, globefish, toadfish), which are eaten. The toxin causes paresthesia and paralysis through interference with neuromuscular conduction

thrombocytopenia
Decrease in the number of blood platelets

thrombosis
Formation, development, or presence of a thrombus. (Dorland 27th ed

toxins
Specific, characterizable, poisonous chemicals, often proteins, with specific biological properties, including immunogenicity, produced by microbes, higher plants, or animals

trimethoprim-sulfamethoxazole combination
4-Amino-N-(5-methyl-3-isoxazolyl)benzenesulfonamide mixture with 5-((3,4,5-trimethoxyphenyl)methyl)- 2,4-pyrimidinediamine. This drug combination has proved to be an effective therapeutic agent with broad-spectrum antibacterial activity against both gram-positive and gram-negative organisms. It is effective in the treatment of many infections, including Pneumocystis carinii pneumonia in AIDS, but is the drug of choice for urinary infection

typhoid
An acute enteric infection caused by SALMONELLA TYPHI

vibrio cholerae
The etiologic agent of CHOLERA

viremia
The presence of viruses in the blood

zooplankton
Minute free-floating animal organisms which live in practically all natural waters