Nalidixic Acid: A synthetic 1,8-naphthyridine antimicrobial agent with a limited bacteriocidal spectrum. It is an inhibitor of the A subunit of bacterial DNA GYRASE.Anti-Infective Agents: Substances that prevent infectious agents or organisms from spreading or kill infectious agents in order to prevent the spread of infection.Enoxacin: A broad-spectrum 6-fluoronaphthyridinone antibacterial agent that is structurally related to NALIDIXIC ACID.Ciprofloxacin: A broad-spectrum antimicrobial carboxyfluoroquinoline.Fluoroquinolones: A group of QUINOLONES with at least one fluorine atom and a piperazinyl group.Quinolones: A group of derivatives of naphthyridine carboxylic acid, quinoline carboxylic acid, or NALIDIXIC ACID.Ofloxacin: A synthetic fluoroquinolone antibacterial agent that inhibits the supercoiling activity of bacterial DNA GYRASE, halting DNA REPLICATION.Microbial Sensitivity Tests: Any tests that demonstrate the relative efficacy of different chemotherapeutic agents against specific microorganisms (i.e., bacteria, fungi, viruses).4-Quinolones: QUINOLONES containing a 4-oxo (a carbonyl in the para position to the nitrogen). They inhibit the A subunit of DNA GYRASE and are used as antimicrobials. Second generation 4-quinolones are also substituted with a 1-piperazinyl group at the 7-position and a fluorine at the 6-position.Anti-Bacterial Agents: Substances that reduce the growth or reproduction of BACTERIA.Pefloxacin: A synthetic broad-spectrum fluoroquinolone antibacterial agent active against most gram-negative and gram-positive bacteria.Drug Resistance, Microbial: The ability of microorganisms, especially bacteria, to resist or to become tolerant to chemotherapeutic agents, antimicrobial agents, or antibiotics. This resistance may be acquired through gene mutation or foreign DNA in transmissible plasmids (R FACTORS).Cinoxacin: Synthetic antimicrobial related to OXOLINIC ACID and NALIDIXIC ACID and used in URINARY TRACT INFECTIONS.Sucralfate: A basic aluminum complex of sulfated sucrose.Pipemidic Acid: Antimicrobial against Gram negative and some Gram positive bacteria. It is protein bound and concentrated in bile and urine and used for gastrointestinal, biliary, and urinary infections.Sulfamethoxazole: A bacteriostatic antibacterial agent that interferes with folic acid synthesis in susceptible bacteria. Its broad spectrum of activity has been limited by the development of resistance. (From Martindale, The Extra Pharmacopoeia, 30th ed, p208)Trimethoprim: A pyrimidine inhibitor of dihydrofolate reductase, it is an antibacterial related to PYRIMETHAMINE. It is potentiated by SULFONAMIDES and the TRIMETHOPRIM, SULFAMETHOXAZOLE DRUG COMBINATION is the form most often used. It is sometimes used alone as an antimalarial. TRIMETHOPRIM RESISTANCE has been reported.QuinolinesNaphthyridinesTrimethoprim-Sulfamethoxazole Combination: 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 PNEUMONIA in AIDS.Urinary Tract Infections: Inflammatory responses of the epithelium of the URINARY TRACT to microbial invasions. They are often bacterial infections with associated BACTERIURIA and PYURIA.N-Terminal Acetyltransferases: Enzymes that catalyze the transfer of an acetyl group, usually from ACETYL COENZYME A, to the N-terminus of a peptide chain.Bacteria: One of the three domains of life (the others being Eukarya and ARCHAEA), also called Eubacteria. They are unicellular prokaryotic microorganisms which generally possess rigid cell walls, multiply by cell division, and exhibit three principal forms: round or coccal, rodlike or bacillary, and spiral or spirochetal. Bacteria can be classified by their response to OXYGEN: aerobic, anaerobic, or facultatively anaerobic; by the mode by which they obtain their energy: chemotrophy (via chemical reaction) or PHOTOTROPHY (via light reaction); for chemotrophs by their source of chemical energy: CHEMOLITHOTROPHY (from inorganic compounds) or chemoorganotrophy (from organic compounds); and by their source for CARBON; NITROGEN; etc.; HETEROTROPHY (from organic sources) or AUTOTROPHY (from CARBON DIOXIDE). They can also be classified by whether or not they stain (based on the structure of their CELL WALLS) with CRYSTAL VIOLET dye: gram-negative or gram-positive.Hexanes: Six-carbon saturated hydrocarbon group of the methane series. Include isomers and derivatives. Various polyneuropathies are caused by hexane poisoning.Nitrofurantoin: A urinary anti-infective agent effective against most gram-positive and gram-negative organisms. Although sulfonamides and antibiotics are usually the agents of choice for urinary tract infections, nitrofurantoin is widely used for prophylaxis and long-term suppression.DNA Gyrase: A bacterial DNA topoisomerase II that catalyzes ATP-dependent breakage of both strands of DNA, passage of the unbroken strands through the breaks, and rejoining of the broken strands. Gyrase binds to DNA as a heterotetramer consisting of two A and two B subunits. In the presence of ATP, gyrase is able to convert the relaxed circular DNA duplex into a superhelix. In the absence of ATP, supercoiled DNA is relaxed by DNA gyrase.Cordia: A plant genus of the family BORAGINACEAE. Members contain TRITERPENES and naphthoxirene.Anti-Infective Agents, Urinary: Substances capable of killing agents causing urinary tract infections or of preventing them from spreading.DNA Topoisomerases, Type II: DNA TOPOISOMERASES that catalyze ATP-dependent breakage of both strands of DNA, passage of the unbroken strands through the breaks, and rejoining of the broken strands. These enzymes bring about relaxation of the supercoiled DNA and resolution of a knotted circular DNA duplex.Oxazines: Six-membered heterocycles containing an oxygen and a nitrogen.Topoisomerase II Inhibitors: Compounds that inhibit the activity of DNA TOPOISOMERASE II. Included in this category are a variety of ANTINEOPLASTIC AGENTS which target the eukaryotic form of topoisomerase II and ANTIBACTERIAL AGENTS which target the prokaryotic form of topoisomerase II.Neisseria gonorrhoeae: A species of gram-negative, aerobic bacteria primarily found in purulent venereal discharges. It is the causative agent of GONORRHEA.Drug Resistance, Bacterial: The ability of bacteria to resist or to become tolerant to chemotherapeutic agents, antimicrobial agents, or antibiotics. This resistance may be acquired through gene mutation or foreign DNA in transmissible plasmids (R FACTORS).Oxolinic Acid: Synthetic antimicrobial related to NALIDIXIC ACID and used in URINARY TRACT INFECTIONS.Escherichia coli: A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.Bacterial Infections: Infections by bacteria, general or unspecified.Ethidium: A trypanocidal agent and possible antiviral agent that is widely used in experimental cell biology and biochemistry. Ethidium has several experimentally useful properties including binding to nucleic acids, noncompetitive inhibition of nicotinic acetylcholine receptors, and fluorescence among others. It is most commonly used as the bromide.DNA Topoisomerase IV: A bacterial DNA topoisomerase II that catalyzes ATP-dependent breakage of both strands of DNA, passage of the unbroken strands through the breaks, and rejoining of the broken strands. Topoisomerase IV binds to DNA as a heterotetramer consisting 2 parC and 2 parE subunits. Topoisomerase IV is a decatenating enzyme that resolves interlinked daughter chromosomes following DNA replication.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.Antacids: Substances that counteract or neutralize acidity of the GASTROINTESTINAL TRACT.Cystitis: Inflammation of the URINARY BLADDER, either from bacterial or non-bacterial causes. Cystitis is usually associated with painful urination (dysuria), increased frequency, urgency, and suprapubic pain.Drug Interactions: The action of a drug that may affect the activity, metabolism, or toxicity of another drug.Bacteroides fragilis: Gram-negative bacteria occurring in the lower intestinal tracts of man and other animals. It is the most common species of anaerobic bacteria isolated from human soft tissue infections.Convulsants: Substances that act in the brain stem or spinal cord to produce tonic or clonic convulsions, often by removing normal inhibitory tone. They were formerly used to stimulate respiration or as antidotes to barbiturate overdose. They are now most commonly used as experimental tools.Rwanda: A republic in eastern Africa, south of UGANDA, east of DEMOCRATIC REPUBLIC OF THE CONGO, west of TANZANIA. Its capital is Kigali. It was formerly part of the Belgian trust territory of Ruanda-Urund.Feces: Excrement from the INTESTINES, containing unabsorbed solids, waste products, secretions, and BACTERIA of the DIGESTIVE SYSTEM.Administration, Oral: The giving of drugs, chemicals, or other substances by mouth.Phenylacetates: Derivatives of phenylacetic acid. Included under this heading are a variety of acid forms, salts, esters, and amides that contain the benzeneacetic acid structure. Note that this class of compounds should not be confused with derivatives of phenyl acetate, which contain the PHENOL ester of ACETIC ACID.Levofloxacin: The L-isomer of Ofloxacin.Waste Water: Contaminated water generated as a waste product of human activity.Staphylococcus aureus: Potentially pathogenic bacteria found in nasal membranes, skin, hair follicles, and perineum of warm-blooded animals. They may cause a wide range of infections and intoxications.Pseudomonas aeruginosa: A species of gram-negative, aerobic, rod-shaped bacteria commonly isolated from clinical specimens (wound, burn, and urinary tract infections). It is also found widely distributed in soil and water. P. aeruginosa is a major agent of nosocomial infection.Biological Availability: The extent to which the active ingredient of a drug dosage form becomes available at the site of drug action or in a biological medium believed to reflect accessibility to a site of action.Spectinomycin: An antibiotic produced by Streptomyces spectabilis. It is active against gram-negative bacteria and used for the treatment of gonorrhea.Dysentery, Bacillary: DYSENTERY caused by gram-negative rod-shaped enteric bacteria (ENTEROBACTERIACEAE), most often by the genus SHIGELLA. Shigella dysentery, Shigellosis, is classified into subgroups according to syndrome severity and the infectious species. Group A: SHIGELLA DYSENTERIAE (severest); Group B: SHIGELLA FLEXNERI; Group C: SHIGELLA BOYDII; and Group D: SHIGELLA SONNEI (mildest).Thiamphenicol: A methylsulfonyl analog of CHLORAMPHENICOL. It is an antibiotic and immunosuppressive agent.Nicotinic Acids: 2-, 3-, or 4-Pyridinecarboxylic acids. Pyridine derivatives substituted with a carboxy group at the 2-, 3-, or 4-position. The 3-carboxy derivative (NIACIN) is active as a vitamin.Ascites: Accumulation or retention of free fluid within the peritoneal cavity.Gonorrhea: Acute infectious disease characterized by primary invasion of the urogenital tract. The etiologic agent, NEISSERIA GONORRHOEAE, was isolated by Neisser in 1879.Fleroxacin: A broad-spectrum antimicrobial fluoroquinolone. The drug strongly inhibits the DNA-supercoiling activity of DNA GYRASE.Drug Resistance, Multiple, Bacterial: The ability of bacteria to resist or to become tolerant to several structurally and functionally distinct drugs simultaneously. This resistance may be acquired through gene mutation or foreign DNA in transmissible plasmids (R FACTORS).Aminoglycosides: Glycosylated compounds in which there is an amino substituent on the glycoside. Some of them are clinically important ANTIBIOTICS.Escherichia coli Infections: Infections with bacteria of the species ESCHERICHIA COLI.Tetracycline: A naphthacene antibiotic that inhibits AMINO ACYL TRNA binding during protein synthesis.Gram-Negative Bacteria: Bacteria which lose crystal violet stain but are stained pink when treated by Gram's method.Premedication: Preliminary administration of a drug preceding a diagnostic, therapeutic, or surgical procedure. The commonest types of premedication are antibiotics (ANTIBIOTIC PROPHYLAXIS) and anti-anxiety agents. It does not include PREANESTHETIC MEDICATION.Carbonyl Cyanide m-Chlorophenyl Hydrazone: A proton ionophore. It is commonly used as an uncoupling agent and inhibitor of photosynthesis because of its effects on mitochondrial and chloroplast membranes.Polysorbates: Sorbitan mono-9-octadecanoate poly(oxy-1,2-ethanediyl) derivatives; complex mixtures of polyoxyethylene ethers used as emulsifiers or dispersing agents in pharmaceuticals.DNA, Bacterial: Deoxyribonucleic acid that makes up the genetic material of bacteria.Spheroplasts: Cells, usually bacteria or yeast, which have partially lost their cell wall, lost their characteristic shape and become round.Absorption: The physical or physiological processes by which substances, tissue, cells, etc. take up or take in other substances or energy.Enterococcus faecalis: A species of gram-positive, coccoid bacteria commonly isolated from clinical specimens and the human intestinal tract. Most strains are nonhemolytic.Digestive System: A group of organs stretching from the MOUTH to the ANUS, serving to breakdown foods, assimilate nutrients, and eliminate waste. In humans, the digestive system includes the GASTROINTESTINAL TRACT and the accessory glands (LIVER; BILIARY TRACT; PANCREAS).Mutation: Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.Aminocoumarins: COUMARINS with an amino group, exemplified by NOVOBIOCIN.Random Allocation: A process involving chance used in therapeutic trials or other research endeavor for allocating experimental subjects, human or animal, between treatment and control groups, or among treatment groups. It may also apply to experiments on inanimate objects.Bacterial Proteins: Proteins found in any species of bacterium.Lactams: Cyclic AMIDES formed from aminocarboxylic acids by the elimination of water. Lactims are the enol forms of lactams.Imipenem: Semisynthetic thienamycin that has a wide spectrum of antibacterial activity against gram-negative and gram-positive aerobic and anaerobic bacteria, including many multiresistant strains. It is stable to beta-lactamases. Clinical studies have demonstrated high efficacy in the treatment of infections of various body systems. Its effectiveness is enhanced when it is administered in combination with CILASTATIN, a renal dipeptidase inhibitor.Eyelids: Each of the upper and lower folds of SKIN which cover the EYE when closed.Herb-Drug Interactions: The effect of herbs, other PLANTS, or PLANT EXTRACTS on the activity, metabolism, or toxicity of drugs.Drug Combinations: Single preparations containing two or more active agents, for the purpose of their concurrent administration as a fixed dose mixture.Chloramphenicol: An antibiotic first isolated from cultures of Streptomyces venequelae in 1947 but now produced synthetically. It has a relatively simple structure and was the first broad-spectrum antibiotic to be discovered. It acts by interfering with bacterial protein synthesis and is mainly bacteriostatic. (From Martindale, The Extra Pharmacopoeia, 29th ed, p106)Proteus Infections: Infections with bacteria of the genus PROTEUS.Corynebacterium: A genus of asporogenous bacteria that is widely distributed in nature. Its organisms appear as straight to slightly curved rods and are known to be human and animal parasites and pathogens.Cefotaxime: Semisynthetic broad-spectrum cephalosporin.Bacterial Outer Membrane Proteins: Proteins isolated from the outer membrane of Gram-negative bacteria.Staphylococcus: A genus of gram-positive, facultatively anaerobic, coccoid bacteria. Its organisms occur singly, in pairs, and in tetrads and characteristically divide in more than one plane to form irregular clusters. Natural populations of Staphylococcus are found on the skin and mucous membranes of warm-blooded animals. Some species are opportunistic pathogens of humans and animals.SOS Response (Genetics): An error-prone mechanism or set of functions for repairing damaged microbial DNA. SOS functions (a concept reputedly derived from the SOS of the international distress signal) are involved in DNA repair and mutagenesis, in cell division inhibition, in recovery of normal physiological conditions after DNA repair, and possibly in cell death when DNA damage is extensive.Ampicillin: Semi-synthetic derivative of penicillin that functions as an orally active broad-spectrum antibiotic.Enterobacteriaceae Infections: Infections with bacteria of the family ENTEROBACTERIACEAE.Mycobacterium: A genus of gram-positive, aerobic bacteria. Most species are free-living in soil and water, but the major habitat for some is the diseased tissue of warm-blooded hosts.Half-Life: The time it takes for a substance (drug, radioactive nuclide, or other) to lose half of its pharmacologic, physiologic, or radiologic activity.Diarrhea: An increased liquidity or decreased consistency of FECES, such as running stool. Fecal consistency is related to the ratio of water-holding capacity of insoluble solids to total water, rather than the amount of water present. Diarrhea is not hyperdefecation or increased fecal weight.Corneal Ulcer: Loss of epithelial tissue from the surface of the cornea due to progressive erosion and necrosis of the tissue; usually caused by bacterial, fungal, or viral infection.Eye Infections, Bacterial: Infections in the inner or external eye caused by microorganisms belonging to several families of bacteria. Some of the more common genera found are Haemophilus, Neisseria, Staphylococcus, Streptococcus, and Chlamydia.DNA, Superhelical: Circular duplex DNA isolated from viruses, bacteria and mitochondria in supercoiled or supertwisted form. This superhelical DNA is endowed with free energy. During transcription, the magnitude of RNA initiation is proportional to the DNA superhelicity.Peritonitis: INFLAMMATION of the PERITONEUM lining the ABDOMINAL CAVITY as the result of infectious, autoimmune, or chemical processes. Primary peritonitis is due to infection of the PERITONEAL CAVITY via hematogenous or lymphatic spread and without intra-abdominal source. Secondary peritonitis arises from the ABDOMINAL CAVITY itself through RUPTURE or ABSCESS of intra-abdominal organs.Gentamicins: A complex of closely related aminoglycosides obtained from MICROMONOSPORA purpurea and related species. They are broad-spectrum antibiotics, but may cause ear and kidney damage. They act to inhibit PROTEIN BIOSYNTHESIS.Colony Count, Microbial: Enumeration by direct count of viable, isolated bacterial, archaeal, or fungal CELLS or SPORES capable of growth on solid CULTURE MEDIA. The method is used routinely by environmental microbiologists for quantifying organisms in AIR; FOOD; and WATER; by clinicians for measuring patients' microbial load; and in antimicrobial drug testing.Seizures: Clinical or subclinical disturbances of cortical function due to a sudden, abnormal, excessive, and disorganized discharge of brain cells. Clinical manifestations include abnormal motor, sensory and psychic phenomena. Recurrent seizures are usually referred to as EPILEPSY or "seizure disorder."Acinetobacter: A genus of gram-negative bacteria of the family MORAXELLACEAE, found in soil and water and of uncertain pathogenicity.Biotransformation: The chemical alteration of an exogenous substance by or in a biological system. The alteration may inactivate the compound or it may result in the production of an active metabolite of an inactive parent compound. The alterations may be divided into METABOLIC DETOXICATION, PHASE I and METABOLIC DETOXICATION, PHASE II.Gram-Positive Bacteria: Bacteria which retain the crystal violet stain when treated by Gram's method.Theophylline: A methyl xanthine derivative from tea with diuretic, smooth muscle relaxant, bronchial dilation, cardiac and central nervous system stimulant activities. Theophylline inhibits the 3',5'-CYCLIC NUCLEOTIDE PHOSPHODIESTERASE that degrades CYCLIC AMP thus potentiates the actions of agents that act through ADENYLYL CYCLASES and cyclic AMP.Antiporters: Membrane transporters that co-transport two or more dissimilar molecules in the opposite direction across a membrane. Usually the transport of one ion or molecule is against its electrochemical gradient and is "powered" by the movement of another ion or molecule with its electrochemical gradient.Ophthalmic Solutions: Sterile solutions that are intended for instillation into the eye. It does not include solutions for cleaning eyeglasses or CONTACT LENS SOLUTIONS.Multidrug Resistance-Associated Proteins: A sequence-related subfamily of ATP-BINDING CASSETTE TRANSPORTERS that actively transport organic substrates. Although considered organic anion transporters, a subset of proteins in this family have also been shown to convey drug resistance to neutral organic drugs. Their cellular function may have clinical significance for CHEMOTHERAPY in that they transport a variety of ANTINEOPLASTIC AGENTS. Overexpression of proteins in this class by NEOPLASMS is considered a possible mechanism in the development of multidrug resistance (DRUG RESISTANCE, MULTIPLE). Although similar in function to P-GLYCOPROTEINS, the proteins in this class share little sequence homology to the p-glycoprotein family of proteins.Urine: Liquid by-product of excretion produced in the kidneys, temporarily stored in the bladder until discharge through the URETHRA.Klebsiella Infections: Infections with bacteria of the genus KLEBSIELLA.Chromatography, High Pressure Liquid: Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.Ethambutol: An antitubercular agent that inhibits the transfer of mycolic acids into the cell wall of the tubercle bacillus. It may also inhibit the synthesis of spermidine in mycobacteria. The action is usually bactericidal, and the drug can penetrate human cell membranes to exert its lethal effect. (From Smith and Reynard, Textbook of Pharmacology, 1992, p863)Genes, Bacterial: The functional hereditary units of BACTERIA.Culture Media: Any liquid or solid preparation made specifically for the growth, storage, or transport of microorganisms or other types of cells. The variety of media that exist allow for the culturing of specific microorganisms and cell types, such as differential media, selective media, test media, and defined media. Solid media consist of liquid media that have been solidified with an agent such as AGAR or GELATIN.Drug Resistance, Multiple: Simultaneous resistance to several structurally and functionally distinct drugs.Plasmids: Extrachromosomal, usually CIRCULAR DNA molecules that are self-replicating and transferable from one organism to another. They are found in a variety of bacterial, archaeal, fungal, algal, and plant species. They are used in GENETIC ENGINEERING as CLONING VECTORS.Antimetabolites: Drugs that are chemically similar to naturally occurring metabolites, but differ enough to interfere with normal metabolic pathways. (From AMA Drug Evaluations Annual, 1994, p2033)Staphylococcal Infections: Infections with bacteria of the genus STAPHYLOCOCCUS.Pseudomonas Infections: Infections with bacteria of the genus PSEUDOMONAS.Campylobacter Infections: Infections with bacteria of the genus CAMPYLOBACTER.Streptococcus: A genus of gram-positive, coccoid bacteria whose organisms occur in pairs or chains. No endospores are produced. Many species exist as commensals or parasites on man or animals with some being highly pathogenic. A few species are saprophytes and occur in the natural environment.Spectrometry, Fluorescence: Measurement of the intensity and quality of fluorescence.Administration, Topical: The application of drug preparations to the surfaces of the body, especially the skin (ADMINISTRATION, CUTANEOUS) or mucous membranes. This method of treatment is used to avoid systemic side effects when high doses are required at a localized area or as an alternative systemic administration route, to avoid hepatic processing for example.Microbial Viability: Ability of a microbe to survive under given conditions. This can also be related to a colony's ability to replicate.Milk: The white liquid secreted by the mammary glands. It contains proteins, sugar, lipids, vitamins, and minerals.Hydrogen-Ion Concentration: The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)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.Vibrio cholerae: The etiologic agent of CHOLERA.Cell Membrane Permeability: A quality of cell membranes which permits the passage of solvents and solutes into and out of cells.Intestinal Absorption: Uptake of substances through the lining of the INTESTINES.Membrane Transport Proteins: Membrane proteins whose primary function is to facilitate the transport of molecules across a biological membrane. Included in this broad category are proteins involved in active transport (BIOLOGICAL TRANSPORT, ACTIVE), facilitated transport and ION CHANNELS.Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.Norfloxacin: A synthetic fluoroquinolone (FLUOROQUINOLONES) with broad-spectrum antibacterial activity against most gram-negative and gram-positive bacteria. Norfloxacin inhibits bacterial DNA GYRASE.PiperazinesActinomycetales: An order of gram-positive, primarily aerobic BACTERIA that tend to form branching filaments.Methicillin Resistance: Non-susceptibility of a microbe to the action of METHICILLIN, a semi-synthetic penicillin derivative.Gene Expression Regulation, Bacterial: Any of the processes by which cytoplasmic or intercellular factors influence the differential control of gene action in bacteria.Cloning, Molecular: The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.Double-Blind Method: A method of studying a drug or procedure in which both the subjects and investigators are kept unaware of who is actually getting which specific treatment.beta-Lactamases: Enzymes found in many bacteria which catalyze the hydrolysis of the amide bond in the beta-lactam ring. Well known antibiotics destroyed by these enzymes are penicillins and cephalosporins.Clinical Trials as Topic: Works about pre-planned studies of the safety, efficacy, or optimum dosage schedule (if appropriate) of one or more diagnostic, therapeutic, or prophylactic drugs, devices, or techniques selected according to predetermined criteria of eligibility and observed for predefined evidence of favorable and unfavorable effects. This concept includes clinical trials conducted both in the U.S. and in other countries.Drug Synergism: The action of a drug in promoting or enhancing the effectiveness of another drug.Time Factors: Elements of limited time intervals, contributing to particular results or situations.IndiaBiological Transport: The movement of materials (including biochemical substances and drugs) through a biological system at the cellular level. The transport can be across cell membranes and epithelial layers. It also can occur within intracellular compartments and extracellular compartments.Magnetic Resonance Spectroscopy: Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).Sequence Analysis, DNA: A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.Acute Disease: Disease having a short and relatively severe course.Infusions, Intravenous: The long-term (minutes to hours) administration of a fluid into the vein through venipuncture, either by letting the fluid flow by gravity or by pumping it.Rabbits: The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.Polymerase Chain Reaction: In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.Recurrence: The return of a sign, symptom, or disease after a remission.Rats, Sprague-Dawley: A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.Kinetics: The rate dynamics in chemical or physical systems.Amino Acid Sequence: The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.Dose-Response Relationship, Drug: The relationship between the dose of an administered drug and the response of the organism to the drug.Rats, Inbred Strains: Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.Prospective Studies: Observation of a population for a sufficient number of persons over a sufficient number of years to generate incidence or mortality rates subsequent to the selection of the study group.Treatment Outcome: Evaluation undertaken to assess the results or consequences of management and procedures used in combating disease in order to determine the efficacy, effectiveness, safety, and practicability of these interventions in individual cases or series.