Medical Dictionary banner
Medical Dictionary - Dictionary of Medicine and Human Biology

Medical Dictionary


bactericidal (bak-ter′i-si′dal)
Destroying bacteria. Cf.:bacteriostatic. SYN: bacteriocidal.

bactericide (bak-ter′i-sid)
An agent that kills bacteria. Cf.:bacteriostat. SYN: bacteriocide. [bacteria + L. caedo, to kill]
    specific b.: a bacteriolytic substance i.e., immune serum that kills only one bacterial species or genus
bacterid (bak′ter-id)
  • Skin eruption associated with bacterial infection
  • A recurrent or persistent eruption of discrete sterile pustules of the palms and soles, thought to be an allergic response to bacterial infection at a remote site.
  • A dissemination of a previously localized bacterial skin infection. [bacteria + -id (1)]
bacteriemia (bak-ter-e-e′me-a)
SYN: bacteremia.

bacterio-, bacteri-
Bacteria. [see bacterium]

bacterioagglutinin (bak-ter′e-o-a-gloo′ti-nin)
An antibody that agglutinates bacteria.

bacteriochlorin (bak-ter′-e-o-klor′in)
7,8,17,18-Tetrahydroporphyrin;the basic structure of the bacteriochlorophylls.

bacteriochlorophyll (bak-ter-e-o-klor′o-fil)
Any form of chlorophyll in photosynthetic bacteria: 1) b. a, &cbond;CH&dbond;CH2 replaced by &cbond;CO&cbond;CH3 in the chlorophyll α structure, two hydrogens also being added; the photosynthetic pigments of purple bacteria; 2) b. b, &cbond;CH&dbond;CH2 replaced by &cbond;CO&cbond;CH3 and &cbond;CH2&cbond;CH3 replaced by &cbond;C&tbond;CH in the chlorophyll β structure, two hydrogens also being added.

bacteriocidal (bak-ter′e-o-si′dal)
SYN: bactericidal.

bacteriocide (bak-ter′e-o-sid)
SYN: bactericide.

bacteriocidin (bak-ter′e-o-si′din)
Antibody having bactericidal activity.

bacteriocinogens (bak-ter′e-o-sin′o-jenz)
SYN: bacteriocinogenic plasmids, under plasmid.

bacteriocins (bak-ter′e-o-sinz)
Proteins produced by certain bacteria that have bacteriocinogenic plasmids and that exert a lethal effect on closely related bacteria; in general, b. have a narrower range of activity than antibiotics and are more potent.

bacteriofluorescin (bak-ter′e-o-flor-es′in)
A fluorescent material produced by bacteria.

bacteriogenic (bak-ter′e-o-jen′ik)
Caused by bacteria.

bacteriogenous (bak-ter-e-oj′e-nus)
1. Producing bacteria. 2. Of bacterial origin or causation.

bacterioid (bak-ter′e-oyd)
1. Resembling bacteria. 2. Intracellular forms of Rhizobium spp. in the root nodules of leguminous plants. [bacterio- + G. eidos, resemblance]

bacteriologic, bacteriological (bak′ter-e-o-loj′ik, -i-kal)
Relating to bacteria or to bacteriology.

bacteriologist (bak′ter-e-ol′o-jist)
One who primarily studies or works with bacteria.

bacteriology (bak-ter-e-ol′o-je)
The branch of science concerned with the study of bacteria. [bacterio- + G. logos, study] systematic b. that branch of b. concerned with nomenclature and classification (taxonomy).

bacteriolysin (bak-ter-e-ol′i-sin)
Specific antibody that combines with bacterial cells ( i.e., antigen) and, in the presence of complement, causes lysis or dissolution of the cells.

bacteriolysis (bak-ter-e-ol′i-sis)
The dissolution of bacteria, e.g., by means of enzymes, hypotonic solutions, or specific antibody and complement. [bacterio- + G. lysis, dissolution]

bacteriolytic (bak-ter-e-o-lit′ik)
Pertaining to lytic destruction of bacteria; manifesting the ability to cause dissolution of bacterial cells.

bacteriolyze (bak-ter′e-o-liz)
To cause the digestion or solution of bacterial cells.

bacteriopexy (bak-ter′e-o-pek-se)
Immobilization of bacteria by phagocytic cells. [bacterio- + G. pexis, fixation]

bacteriophage (bak-ter′e-o-faj)
A virus with specific affinity for bacteria. Bacteriophages have been found in association with essentially all groups of bacteria, including the Cyanobacteria; like other viruses they contain either (but never both) RNA or DNA and vary in structure from the seemingly simple filamentous bacterial virus to relatively complex forms with contractile “tails”; their relationships to the host bacteria are highly specific and, as in the case of temperate b., may be genetically intimate. Bacteriophages are named after the bacterial species, group, or strain for which they are specific, e.g., corynebacteriophage, coliphage; a number of families are recognized and have been assigned provisional names: Corticoviridae, Cystoviridae, Fuselloviridae, Inoviridae, Leviviridae, Lipothrixviridae, Microviridae, Myoviridae, Plasmaviridae, Podoviridae, Styloviridae, and Tectiviridae. SEE ALSO: coliphage. SYN: phage. [bacterio- + G. phago, to eat] defective b. a temperate b. mutant whose genome does not contain all of the normal components and cannot become a fully infectious virus, yet can replicate indefinitely in the bacterial genome as defective probacteriophage; many defective bacteriophages are mediators of transduction. SYN: defective phage. filamentous b. a b. that is rod-shaped and elongated lacking the head-and-tail structure characteristic of many bacteriophages. mature b. the complete, infective form of b.. temperate b. b. whose genome incorporates with, and replicates with, that of the host bacterium; dissociation (and resultant development of vegetative b.) occurs at a slow rate resulting occasionally in lysis of a bacterium and release of mature b., thus rendering the bacterial culture capable of inducing general lysis if transferred to a culture of a susceptible bacterial strain. typhoid b. b. specific for Salmonella typhi. vegetative b. the form of b. in which the b. nucleic acid (lacking its coat) multiplies freely within the host bacterium, independently of bacterial multiplication. virulent b. a b. that regularly causes lysis of the bacteria that it infects; it may exist in one or the other of only two forms, vegetative or mature; it does not have a probacteriophage form ( i.e., its genome does not incorporate with that of the host bacterium), therefore it does not effect lysogenization.

bacteriophagia (bak-ter′e-o-fa′je-a)
Lysis of bacteria by a bacteriophage.

bacteriophagology (bak-ter′e-o-fa-gol′o-je)
The study of bacteriophages. SYN: protobiology.

bacteriopheophorbin (bak-ter′e-o-fe-o-for′bin)
De-esterified bacteriopheophorbide, derived from bacteriochlorin.

bacteriophytoma (bak-ter′e-o-fi-to′ma)
A growth in plant tissues produced by bacteria. [bacterio- + G. phytos, plant, + -oma, growth]

bacterioprotein (bak-ter′e-o-pro′ten)
One of the proteins within the cells of bacteria; these substances vary in their character and properties.

bacteriopsonin (bak-ter-e-op′so-nin)
An opsonin that may be an antibody acting upon bacteria rendering them susceptible to phagocytic cells.

bacteriosis (bak-ter-e-o′sis)
A localized or generalized bacterial infection.

bacteriospermia (bak′ter-e-o-sper-me-a)
Bacteria in the semen or ejaculate.

bacteriostasis (bak-ter-e-os′ta-sis)
An arrest or retardation of growth of bacteria. [bacterio- + G. stasis, a standing still]

bacteriostat (bak-ter′e-o-stat)
Any agent that inhibits or retards bacterial growth. SYN: bacteriostatic agent.

bacteriostatic (bak-ter′e-o-stat′ik)
Inhibiting or retarding the multiplication of bacteria.

bacteriotoxic (bak-ter′e-o-tok′sik)
Poisonous or toxic to bacteria.

bacteriotropic (bak-ter′e-o-trop′ik)
Turning toward or moving in the direction of bacteria; having an affinity for bacteria. [bacterio- + G. trope, a turning]

bacteriotropin (bak-ter-e-ot′ro-pin)
A constituent of the blood, usually a specific antibody, i.e., opsonin, that combines with bacterial cells and renders them more susceptible to phagocytes.

bacteriotrypsin (bak-ter′e-o-trip′sin)
A trypsinlike enzyme produced by bacteria, particularly Vibrio cholerae.

Bacterium (bak-ter′e-um)
A bacterial generic name placed on the list of rejected names by the Judicial Commission and the International Committee on Systematic Bacteriology of the International Association of Microbiological Societies. As a consequence, B. is no longer used in bacteriology. Identifiable organisms formerly placed in the genus B. have all been transferred to other genera. Specifically, B. anitratum is now known as Acinetobacter calcoaceticus; B. coli is now called Escherichia coli. [Mod. L. fr. G. bakterion, dim. of baktron, a staff or club]

bacterium (bak-ter′e-um)
A unicellular prokaryotic microorganism that usually multiplies by cell division and has a cell wall that provides a constancy of form; they may be aerobic or anaerobic, motile or nonmotile, and free-living, saprophytic, commensal, parasitic, or pathogenic. SEE ALSO: Cyanobacteria. [Mod. L. fr. G. bakterion, dim. of baktron, a staff] blue-green b. Cyanobacteria. endoteric b. a b. that forms an endotoxin. exoteric b. a b. that secretes an exotoxin. lysogenic b. a b. genome includes the genome (probacteriophage) of a temperate bacteriophage; in occasional instances the probacteriophage dissociates from the bacterial genome, develops into vegetative bacteriophage, and then matures, causing lysis of the respective host b. and release into the culture medium of infective temperate bacteriophage; pyogenic b. a b. that causes a pyogenic infection usually associated with purulent exudate containing polymorphonuclear leukocytes such as the pyogenic cocci (staphylococci, streptococci, pneumococci, meningococci) and Haemophilus influenzae.

bacteriuria (bak-ter-e-oo′re-a)
The presence of bacteria in the urine.

bacteroid (bak′ter-oyd)
Resembling bacteria.

Bacteroidaceae (bak′ter-oy-da′se-e)
A family of obligate anaerobic (microaerophilic species may occur), nonsporeforming bacteria (order Eubacteriales) containing Gram-negative rods which vary in size from minute, filterable forms to long, filamentous, branching forms; pronounced pleomorphism may occur. Motile and nonmotile species occur; motile cells are peritrichous. Body fluids are frequently required for growth. Most species ferment carbohydrates, often with the production of acid; gas may be produced in glucose or peptone media. These organisms occur primarily in the lower intestinal tracts and mucous membranes of warm-blooded animals. They may be pathogenic. The type genus is Bacteroides.

Bacteroides (bak-ter-oy′dez)
A genus that includes many species of obligate anaerobic, nonsporeforming bacteria (family Bacteroidaceae) containing Gram-negative rods. Both motile and nonmotile species occur; motile cells are peritrichous. Some species ferment carbohydrates and produce combinations of succinic, lactic, acetic, formic, or propionic acids, sometimes with short-chained alcohols; butyric acid is not a major product. Those species which do not ferment carbohydrates produce from peptone either trace to moderate amounts of succinic, formic, acetic, and lactic acids or major amounts of acetic and butyric acids with moderate amounts of alcohols and isovaleric, propionic, and isobutyric acids. They are part of the normal flora of the intestinal tract and to a lesser degree, the respiratory, and urogenital cavities of humans and animals; many species formerly classified as B. have been reclassified as belonging to the genus Prevotella. Many species can be pathogenic. The type species is B. fragilis. [G. bacterion + eidos, form] B. bivius a species usually isolated from urogenital and abdominal infections and linked to pelvic inflammatory disease. B. capillosus a bacterial species isolated from human cysts and wounds, the mouth, and feces, and from the intestinal tracts of some animals. Its properties differ from those of most B. species; future reclassification is likely. B. corrodens former name for Eikenella corrodens. B. disiens SYN: Prevotella disiens. B. distasonis bacterial species that is part of the normal human fecal flora; an occasional cause of intraabdominal infections. B. fragilis a bacterial species found in human and animal intestinal tracts. Although it represents only about 10–20% of B. species found in the colon, it is the primary species associated with intraabdominal abscesses and other subdiaphragmatic infections in humans, including peritonitis, rectal abscess, abdominal surgical wounds, and urogenital tract infection. Its capsule is capable of inducing abscess formation independently; characteristically, this species produces a β-lactamase that inactivates β-lactam antibiotics such as the penicillin and cephalosporin groups; it is the type species of the genus, B.. B. furcosus former name of Anaerohabdus furcosis. B. melaninogenicus SYN: Prevotella melaninogenica. B. nodosus a bacterial species that causes foot rot in sheep and goats; it can be found in the human intestinal tract and has been associated with human infections; this organism has many properties different from other species of B., and its final classification is uncertain. SYN: Dichelobacter nodosus. B. oralis former name of Prevotella oralis. B. oris former name of Prevotella oris. B. pneumosintes former name for Dialister pneumosintes. B. praeacutus a species isolated from the intestinal tracts of infants and adults, gangrenous lesions, lung abscesses, and blood. SYN: Tissierella praeacuta. B. putredinis a species isolated from feces, cases of acute appendicitis, and abdominal and rectal abscesses; also from foot rot of sheep and from farm soil. Its properties are divergent from most B. species. B. splanchnicus a species in the indole positive group, found in normal human colonic flora, and occasionally in human specimens with unique metabolic properties that include production of large amounts of n-butyric acid; it appears to be closely related to the genus Porphyromonas. B. thetaiotamicron a bacterial species found in the intestinal tract; second only in its genus to B. fragilis as a cause of human subdiaphragmatic infections. B. ureolyticus a species isolated from infections of the respiratory and intestinal tracts, and from the buccal cavity, intestinal tract, urogenital tract, and blood after a dental extraction. It is closely related to Campylobacter species.

bacteroidosis (bak′ter-oy-do′sis)
Rarely used term for an infection with Bacteroides.

baculiform (ba-ku′li-form)
Rod-shaped. [L. baculum, a rod, + forma, form]

Baculoviridae (bak-u-lo-vir′i-de)
A family of viruses that multiply only in arthropods; virions are rod-shaped and measure 30–35 nm by 250–400 nm; genomes are of double-stranded, supercoiled DNA (90–160 kb). Baculovirus-derived vectors are frequently used to express foreign genes in insect cells. [L. baculum, rod]

baculovirus (bak′oo-lo-vi-rus)
A virus that infects insect cells; used extensively in expression systems for recombinant proteins that require eucaryotic processing systems. [L. baculum, rod, + virus]

George, U.S. physician, 1887–1978. See B.-Lohlein lesion, Lohlein-B. lesion.

Erwin O., German physician in Tokyo, 1849–1913. See B. disease.

Abbreviation for brainstem auditory evoked response. See evoked response.

Karl E. von, German-Russian embryologist, 1792–1876. See B. law.

Johann F.W.A. von, German chemist and Nobel laureate, 1835–1917. See B. theory.

A pouch, sac, or receptacle. [A.S. baelg] Ambu b. proprietary name for a self-reinflating b. with nonrebreathing valves to provide positive pressure ventilation during resuscitation with oxygen or air. breathing b. a collapsible reservoir from which gases are inhaled and into which gases may be exhaled during general anesthesia or artificial ventilation. SYN: reservoir b.. colostomy b. a b. worn over a surgically produced connection between the colon and the skin to collect feces. Douglas b. a large b. in which expired gas is collected for several minutes to determine oxygen consumption in humans under conditions of actual work. [C.G. Douglas] nuclear b. the aggregation of nuclei occurring in the nonstriated center of an intrafusal muscle fiber of a neuromuscular spindle. Politzer b. a pear-shaped rubber b. used for forcing air through the auditory tube by the Politzer method. reservoir b. SYN: breathing b.. b. of waters colloquialism for the amniotic sac and contained amniotic fluid.

bagassosis (bag-a-so′sis)
Extrinsic allergic alveolitis following exposure to sugar-cane fiber dust (bagasse); has been attributed to inhalation of spores of soil fungi and, particularly, thermophilic actinomycetes.

Archie H., U.S. pathologist, *1908. See B. change.

20th century Italian ophthalmologist. See B. test.

Jules G.F., French neurologist, 1809–1891. See B. bands, under band, B. lines, under line.

Paul, French ophthalmologist, 1877–1969. See B. ophthalmodynamometer.

Francis A., English physiologist, 1874–1921. See B. reflex.

William M., English surgeon, 1839–1896. See B. cyst.

James Porter, U.S. physician, *1902. See Charcot-Weiss-B. syndrome.

John Randal, English zoologist, *1900. See B. pyridine extraction, B. acid hematein.

Abbreviation for British anti-Lewisite.

Abbreviation for bronchoalveolar lavage.

Balamuthia (bal-a-moo′the-a)
A genus of free-living ameba that causes granulomatous amebic encephalitis.

See balano-.

balance (bal′ans)
1. An apparatus for weighing; e.g., scales. 2. The normal state of action and reaction between two or more parts or organs of the body. 3. Quantities, concentrations, and proportionate amounts of bodily constituents. 4. The difference between intake and utilization, storage, or excretion of a substance by the body. SEE ALSO: equilibrium. [L. bi-, twice, + lanx, dish, scale] acid-base b. the normal b. between acid and base in the blood plasma, expressed in the hydrogen ion concentration or pH, resulting from the relative amounts of acidic and basic materials ingested and produced by body metabolism, compared to the relative amounts of acidic and basic materials excreted from the body and consumed by body metabolism; the normal state of acid-base b. is not one of neutrality, with equal concentrations of hydrogen and hydroxyl ions, but a more alkaline state with a certain excess of hydroxyl ions. SYN: acid-base equilibrium. nitrogen b. the difference between the total nitrogen intake by an organism and its total nitrogen loss. A zero nitrogen b. is seen in normal, healthy adults; Nin > Nout is a positive nitrogen b. and Nin < Nout is a negative nitrogen b.. occlusal b. a condition in which there are simultaneous contacts of the occluding units of the opposing dental arches in centric and eccentric positions within the functional range. phonetic b. that property by which a group of words used in the measurement of hearing has the various phonemes occurring at approximately the same frequency at which they occur in ordinary conversation in that language; phonetically balanced word lists are used in determining the discrimination score. Wilhelmy b. a device for measuring surface tension in terms of the pull exerted on a thin plate of platinum or other material suspended vertically through the surface; used in a Langmuir trough to study pulmonary surfactant.


. . . Feedback