showing 36 of ~574560 from 574555 documents

Pefloxacin in the Antibacterial Treatment of Immunodepressed Patients

1990

Pefloxacin 800 to 1200 mg daily was given for 3 to 20 days, orally or intravenously, to 84 immunocompromised patients. Five patients dropped out because of side effects and 2 for other causes. Treatment efficacy was evaluated in 77 patients, 43 men and 34 women, aged 18 to 80 years. Immunodepression resulted from malignancy in 46 patients, LAS/ARC or AIDS in 28, and from unknown causes in 3. Fifty-eight patients had documented infections (respiratory-tract infections 29, urinary-tract infections 13, septicemia 10, other 6) and 19 had a fever of unknown origin (FUO). Cure or significant improvement of symptoms was achieved in 81% of patients with documented infections and in 74% of patients …

Adult0301 basic medicinemedicine.medical_specialty030106 microbiologyAIDS-related complexMalignancyPefloxacin03 medical and health sciencesGastrointestinal disturbances0302 clinical medicineAcquired immunodeficiency syndrome (AIDS)NeoplasmsInternal medicineImmune ToleranceHumansMulticenter Studies as TopicMedicinePharmacology (medical)Fever of unknown originAgedAged 80 and overPharmacologyAcquired Immunodeficiency Syndromebusiness.industryBacterial InfectionsMiddle Agedmedicine.diseaseRashPefloxacinTreatment efficacyInfectious DiseasesOncology030220 oncology & carcinogenesismedicine.symptombusinessmedicine.drugJournal of Chemotherapy

Influence of light polarization on the dynamics of optically pumped lasers.

1990

The dynamic behavior of a coherently pumped ring laser with a homogeneously broadened four-level medium is analyzed theoretically, considering linearly polarized pump and generated laser beams. The laser is shown to be much more stable when these polarizations are parallel than when they are orthogonal. In the latter case the instability pump threshold can be as low as four times the first laser threshold, and the laser dynamics shows Lorenz-type features.

PhysicsDistributed feedback laserActive laser mediumbusiness.industryFar-infrared laserPhysics::OpticsLaser pumpingLaserAtomic and Molecular Physics and OpticsSelf-pulsationGain-switchinglaw.inventionOpticslawPhysics::Atomic PhysicsLaser power scalingbusinessPhysical review. A, Atomic, molecular, and optical physics

Antigens of the major histocompatibility complex in patients with chronic discoid lupus erythematosus.

1990

summary The frequencies of the major histocompatability complex class I, class II and class III antigens were determined in 130 patients (88 women and 42 men) with chronic discoid lupus erythematosus, and compared with those of 764 healthy controls. A significant increase in HLA-B7 (38.0% in the patients vs. 25·8% in the control group), HLA-B8 (29·5% vs. 17·4%), HLA-Cw7 (58·9% vs. 26·1%), HLA-DR2 (46·9% vs. 29·7%), HLA-DR3 (32·0% vs. 19·4%), HLA-DQwi (76·6% vs. 60·5%), and a decrease in HLA-A2 (41·9% vs. 55·7%) was found. The calculated relative risk values for the respective antigens markedly increased when two or more antigens were present in one patient, with a maximum relative risk valu…

MaleRiskmedicine.medical_specialtySystemic diseaseDermatologyHLA-C AntigensMajor histocompatibility complexGastroenterologyHLA-B8 AntigenHLA-B7 AntigenHLA-DR3 AntigenLupus Erythematosus DiscoidAntigenHLA AntigensInternal medicineHLA-DQ AntigensHLA-A2 AntigenmedicineHumansIn patientHLA-DR2 AntigenLupus erythematosusbiologybusiness.industrymedicine.diseaseConnective tissue diseaseRelative riskImmunologyChronic Diseasebiology.proteinFemaleDisease SusceptibilitybusinessChronic discoid lupus erythematosusThe British journal of dermatology

Prehnite: Structural similarity of the monoclinic and orthorhombic polymorphs and their Si/Al ordering

1990

Abstract Two modifications of the naturally occurring mineral prehnite, Ca 2 Al(Si 3 AlO 10 )(OH) 2 , are characterized by precise single crystal diffraction methods. The two forms are topologically identical. They differ only in the siting of one Al and one Si atom per unit cell: these switch their places in two of the tetrahedrally coordinated sites. This appears to be the only known case where a silicate occurs with two differently ordered tetrahedral distributions of Al and Si atoms. The two forms are not polytypes according to the current definition of polytypes. The two modifications are so similar to each other that they differ only in the eighth coordination sphere.

Materials scienceMineralCoordination sphereengineering.materialCondensed Matter PhysicsSilicateElectronic Optical and Magnetic MaterialsInorganic Chemistrychemistry.chemical_compoundPrehniteCrystallographychemistryAtomMaterials ChemistryCeramics and CompositesTetrahedronengineeringOrthorhombic crystal systemPhysical and Theoretical ChemistryMonoclinic crystal systemJournal of Solid State Chemistry

Alterations inras-gene expression and intracellular distribution of protein kinase C in the spongeGeodia cydonium in response to marine pollution

1990

The siliceous spongeGeodia cydonium Jameson was used to study the influence of pollution in marine environments on selected parameters of the intracellular signal transduction pathway. The parameters chosen were: intracellular distribution of protein kinase C (PK-C),ras-gene expression and DNA polymerasealpha (DNA Polalpha) activity. Both PK-C andras-gene product (ras-protein) have previously been established to be key molecules in the intracellular signalling pathway in sponges; increased level ofras-protein mediates events following sponge cell-cell contact. Three unpolluted and three polluted sites in the off-shore seawater around Rovinj (Yugoslavia) were selected for the study in 1989. …

chemistry.chemical_classificationEcologybiologyCell growthAquatic Sciencebiology.organism_classificationTransplantationSpongeCytosolEnzymeBiochemistrychemistryGene expressionEcology Evolution Behavior and SystematicsProtein kinase CIntracellularMarine Biology

The read-out processors of the Aleph time projection chamber and their performance

1990

The Aleph detector is installed on the LEP electron-positron storage ring. Its central tracking detector, a time projection chamber (TPC), has about 50000 channels of sampling electronics. The digitized signals are processed by 72 double-width Fastbus modules built around an MC 68020 processor. The time projection processor is described, and the solutions, both hardware and software, adopted to run and manage such a complex system in a Fastbus-VAX environment are discussed. Practical experience with the system is reported. >

PhysicsNuclear and High Energy PhysicsAlephTime projection chamberbusiness.industryDetectorElectrical engineeringTracking (particle physics)Particle detectorSoftwareNuclear Energy and EngineeringNuclear electronicsElectrical and Electronic EngineeringProjection (set theory)businessComputer hardwareIEEE Transactions on Nuclear Science

Determination of diphenhydramine hydrochloride by flow injection with Bromophenol Blue and turbidimetric measurement

1990

The study of a number of diphenhydramine-dye systems was carried out in order to determine the most suitable precipitate for the turbidimetric determination of diphenhydramine using flow injection (FI). The reagent selected was Bromophenol Blue. The chemical and FI variables were optimised. The calibration graph was linear over the concentration range 50-230 p.p.m. of diphenhydramine hydrochloride. A number of interfering substances were also investigated.

ChromatographyDiphenhydramine hydrochlorideCalibration curveDiphenhydramineBromophenol blueBiochemistryAnalytical Chemistrychemistry.chemical_compoundDiphenhydraminechemistryNephelometry and TurbidimetryReagentElectrochemistrymedicineEnvironmental ChemistryIndicators and ReagentsBromphenol BlueSpectroscopymedicine.drugThe Analyst

Mitochondrial DNA evolution in experimental populations of Drosophila subobscura.

1990

When two mitochondrial DNA (mtDNA) haplotypes of Drosophila subobscura compete in experimental populations with discrete generations, one or the other approaches fixation, depending on the nuclear background with which they are associated. The approach to fixation, however, is strongly dependent on the effective number of females in the population, Nf. Whether or not the ultimate fate of a given mtDNA haplotype is determined by random genetic drift depends on Nf as well as on the relative fitnesses. Our experimental results show that the mtDNA polymorphisms observed in natural populations are affected by interactions among nuclear polymorphisms, random genetic drift, and direct selection on…

GeneticsCell NucleusMitochondrial DNAeducation.field_of_studyMultidisciplinaryHaplotypePopulationPopulation geneticsGenetic VariationBiologyBiological EvolutionDNA MitochondrialDrosophila subobscuraFixation (population genetics)Genetics PopulationGenetic driftHaplotypesEvolutionary biologyGenetic variationChromosome InversionAnimalsDrosophilaeducationResearch Article

On the normal index of maximal subgroups in finite groups

1990

AbstractFor a maximal subgroup M of a finite group G, the normal index of M is the order of a chief factor H/K where H is minimal in the set of normal supplements of M in G. We use the primitive permutation representations of a finite group G and the normal index of its maximal subgroups to obtain results about the influence of the set of maximal subgroups in the structure of G.

CombinatoricsNormal subgroupMaximal subgroupFinite groupNormal p-complementMathematics::Group TheoryAlgebra and Number TheoryOrder (group theory)CosetCharacteristic subgroupIndex of a subgroupMathematics

Alteration of DNA topoisomerase II activity during infection of H9 cells by human immunodeficiency virus type 1 in vitro: a target for potential ther…

1990

Infection of H9 cells with human immunodeficiency virus type 1 (HIV-1) was found to decrease the phosphorylation of DNA topoisomerase II during the initial phase of infection. Simultaneously, with a later overshoot of phosphorylation and the subsequent activation of DNA topoisomerase II, the production of HIV-1 started. Applying three new protein kinase C inhibitors from the class of O-alkylglycerophospholipids we demonstrated that inhibition of protein kinase C-mediated phosphorylation of DNA topoisomerase II resulted in an inhibition of HIV-1 production. Based on the differential effect of the two protein kinase C activators, phorbol ester and bryostatin, we conclude that phosphorylation …

T-LymphocytesMitogen-activated protein kinase kinaseIn Vitro TechniquesMAP2K7Cell LineLactonesVirologyAnimalsPhosphorylationProtein kinase AProtein kinase CProtein Kinase CPharmacologybiologyCyclin-dependent kinase 2LysophosphatidylcholinesRats Inbred StrainsDNA topoisomerase II activityBryostatinsProtein kinase RMolecular biologyRatsDNA Topoisomerases Type Ibiology.proteinHIV-1Tetradecanoylphorbol AcetateCyclin-dependent kinase 9Electrophoresis Polyacrylamide GelMacrolidesAntiviral research

Theoretical study of stationary structures of acetamidine unimolecular decomposition

1990

Abstract The unimolecular decomposition of acetamidine to ammonia and acetonitrile was examined by ab initio methods. Stationary points, i.e. the reactant, product and transition structures, have been characterized. The process has an asynchronous mechanism, the transition state being described as a four-membered ring. To establish the relevance of different basis sets, calculations with eight standard Gaussian basis sets, STO-3G, 3-21G, 4-21G, 4-31G, 6-31G, 6-311G, 6-31G*, and G-31G**, were carried out.

Basis (linear algebra)ChemistryGaussianGaussian orbitalAb initioGeneral Physics and AstronomyRing (chemistry)DecompositionStationary pointsymbols.namesakeComputational chemistryProduct (mathematics)symbolsPhysical and Theoretical Chemistry

[Validity of the use of penbutolol in essential arterial hypertension].

1990

Thirty patients suffering from WHO I-II class slight-moderate essential arterial hypertension were treated with a beta-blocker (Penbutolol) alone and once a day to assess its antihypertensive effectiveness and its affect on heart frequency, lipid metabolism and kidney function. The drug proved highly effective in reducing P.A.S. and P.A.D. values and no negative influence was documented on lipid metabolism, kidney function or heart frequency.

AdultMaleSettore MED/09 - Medicina InternaAdult Aged Blood Pressure/drug effects Diastole Drug Evaluation Female Humans Hypertension/drug therapy* Male Middle Aged Penbutolol/therapeutic use* Propanolamines/therapeutic use* Systole SubstancesSystoleBlood PressureMiddle AgedSettore MED/45 - Scienze Infermieristiche Generali Cliniche E PediatricheSettore MED/11 - Malattie Dell'Apparato CardiovascolarePropanolaminesDiastoleHypertensionDrug EvaluationHumansFemalePenbutololAgedMinerva medica

Phosphorylation of cytochrome P450 isoenzymes in intact hepatocytes and its importance for their function in metabolic processes.

1990

Recent data show that besides the well-known long-term regulation of cytochrome P450-dependent monooxygenase activity by induction there also exists a fast regulation by phosphorylation. This phosphorylation occurs when purified cytochromes P450 are combined with purified protein kinases, and also in intact cells. This process is donor- and acceptor-selective leading to phosphorylation of defined isoenzymes by defined protein kinases. This in turn leads to fast and marked changes in metabolism which are selective for given substrates and regio- and stereo-selective for given positions. This in turn is selectively and differentially influenced by the individual control of the protein kinase …

chemistry.chemical_classificationCytochromebiologyKinaseHealth Toxicology and MutagenesisCytochrome P450General MedicineMetabolismToxicologyIsoenzymesEnzymeBiochemistrychemistryCytochrome P-450 Enzyme SystemLiverbiology.proteinPhosphorylationAnimalsHumansProtein phosphorylationPhosphorylationProtein kinase AArchives of toxicology

The nonadiabatic general-relativistic stellar oscillations

1990

We have derived the equations which govern the linear nonadiabatic general-relativistic radial oscillations. The perturbation produces a heat flux that is coupled with the geometry, through the Einstein field equations of a stellar configuration. The classical limit is recovered. The stability conditions are examined by means of a simplified one-zone model.

PhysicsComputational astrophysicsClassical mechanicsHeat fluxSpace and Planetary ScienceGeneral relativityEinstein field equationsPerturbation (astronomy)Astronomy and AstrophysicsAstrophysics::Earth and Planetary AstrophysicsRelativistic quantum chemistryClassical limitStellar pulsationAstrophysics and Space Science

Effects of Escherichia coli hemolysin on human monocytes. Cytocidal action and stimulation of interleukin 1 release.

1990

Abstract This study reports on the potent cytocidal and interleukin-1 releasing properties of Escherichia coli hemolysin (ECH) on human monocytes. Nanomolar concentrations of purified ECH (250-2,000 ng/ml) caused rapid and irreversible depletion of cellular ATP to levels below 20% of controls within 60 min. Subcytocidal doses (10-200 ng/ml) of ECH induced rapid release within 60-120 min of large amounts of interleukin 1 beta (IL-1 beta) from cultured monocytes. IL-1 beta release occurred in the presence of actinomycin D and cycloheximide, and was thus probably due to processing and export of intracellular IL-1 beta precursor. Incubation of toxin-producing E. coli at ratios of only 0.3-3 col…

LipopolysaccharidesCell SurvivalStimulationIn Vitro TechniquesBiologyCycloheximidemedicine.disease_causeHemolysin ProteinsMonocytesMicrobiologyHemolysin Proteinschemistry.chemical_compoundAdenosine TriphosphateEscherichia colimedicineHumansEscherichia coliCells CulturedToxinMonokinesMonocyteInterleukinDrug SynergismGeneral Medicinemedicine.anatomical_structurechemistrySecretory RateIntracellularResearch ArticleInterleukin-1Journal of Clinical Investigation

Major histocompatibility complex regulation of the class of the immune response: the H-2d haplotype determines poor interferon-γ response to several …

1990

The lymph node cells of CBA (H-2k), but not BALB/c (H-2d) mice, release interferon (IFN)-gamma into the supernatant when immunized with picryl chloride epicutaneously and then exposed to antigen (haptenized cells) in vitro 4 days later. The failure in IFN-gamma production maps to the major histocompatibility complex (MHC; H-2d) in the congenic BALB/c, BALB/k and BALB/b mice. The evidence that this is an MHC regulation of the class of response to a range of antigens and not a classical Ir gene effect is (a) the difference is seen with several antigens including picryl chloride, "oxazolone" and purified protein derivative of tuberculin and (b) BALB/c mice, which fail to produce IFN-gamma, sho…

ImmunologyMice Inbred StrainsDermatitis ContactMajor histocompatibility complexMajor Histocompatibility ComplexPicryl chlorideOxazoloneInterferon-gammaMicechemistry.chemical_compoundImmune systemH-2 AntigensAntigenInterferonmedicineAnimalsImmunology and AllergyInterferon gammaHistocompatibility Antigen H-2DbiologyH-2 AntigensImmunityHaplotypeschemistryImmunologybiology.proteinmedicine.drugEuropean Journal of Immunology

Rapid quantitative method for measuring phagocytosis of Leishmania promastigotes using a double radiolabelling method.

1990

A double radiolabelling method is described for the measurement of phagocytosis of Leishmania major promastigotes in cultures of murine resident peritoneal macrophages. L. major promastigotes were radiolabelled during exponential growth in RPMI supplemented with [125I]5-iodo-2-deoxyuridine. They were used to infect sodium [51Cr]chromate-labelled macrophages. Phagocytosis was evaluated by measuring the radioactivity of the 125IUdR-labelled parasites detectable inside 51Cr-labelled macrophages by a Beckmann gamma 5500 counting system. This was able to count simultaneously, in two different windows the radioactivity of (a) the parasites and (b) the cells. The technique compares favorably with …

Pathologymedicine.medical_specialtyCell Membrane PermeabilityPhagocytosisImmunologyMice Inbred StrainsBiologyMicePhagocytosisIdoxuridinemedicineImmunology and AllergyMacrophageAnimalsLeishmania majorRadiometryLeishmaniasisPeritoneal CavityMicroscopyDouble labelingMacrophagesbiology.organism_classificationLeishmaniaMolecular biologyCell cultureLeishmania tropicaProtozoaJournal of immunological methods

Relaxation, postponement, and features of the attractor in a driven varactor oscillator

1990

The driven varactor oscillator is investigated by numerical integration of its ODEs using the standard model of circuit theory. Attention is given to some properties of the basic relaxation mechanism. For time dependent amplitudes of the sinusoidal driving voltage the post-ponement of the bifurcations is characterized by transient Lyapunov numbers. The postponement of the first bifurcation shows the same dependence on the sweep velocity as in the case of the nonautonomous quadratic map. The shapes of the attractors are displayed in extended phase space. Generalized Renyi-dimensionsD 0 andD 1 have been determined in the chaotic region. A corresponding twodimensional Pioncare map indicates se…

PhysicsLyapunov functionDifferential equationMathematical analysisChaoticCondensed Matter PhysicsElectronic Optical and Magnetic MaterialsNumerical integrationNonlinear Sciences::Chaotic Dynamicssymbols.namesakeAttractorsymbolsRelaxation (physics)General Materials ScienceTransient (oscillation)BifurcationZeitschrift f�r Physik B Condensed Matter

Xanthogranulomatous Cholecystitis

1990

Summary Xanthogranulomatous cholecystitis (XC) is a chronic inflammatory lesion of the gallbladder histologically characterized by the presence of varying amounts of foamy histiocytes in the inflammatory infiltrate. In this study a review of 63 cases selected from 1207 surgically removed gallbladders is presented; the percentage found (5.2%) is slightly higher than that of previous reports showing that XC is less uncommon than generally believed. A detailed microscopic study is performed: the authors observed according to the histological features particularly the different patterns of distribution of the inflammatory infiltrate and postulate the existence of three subtypes of XC: multinodu…

Pathologymedicine.medical_specialtymedicine.anatomical_structurebusiness.industryGallbladdermedicineCell BiologyFoamy histiocytesbusinessInflammatory lesionXanthogranulomatous CholecystitisPathology and Forensic MedicinePathology - Research and Practice

L'immigration dans quelques communes de la banlieue ouest : Asnières, Nanterre et Puteaux de 1830 à 1930

1990

A study of immigration for the period 1 830-1 930 for three communes in the western suburbs of Paris has been undertaken with the aid of official marriage certificates. The study tends to show that each suburban commune's immigrants, coming primarily from the provinces and secondarily from Paris, have been chosen to some extent since they reflect the economic activities and the social composition of the population of the commune of arrival. This selection occuring within national migration streams seems to favour the migrants insertion, at least until the beginning of the twentieth century.

[SHS.DROIT]Humanities and Social Sciences/LawPolymers and Plastics[SHS.DROIT] Humanities and Social Sciences/LawDémographie8. Economic growth[ SHS.DROIT ] Humanities and Social Sciences/LawGeneral Environmental Scienceimmigration

Interaction of Zn(II) and Cd(II) with Large Polyazacycloalkanes in dmso/H2O (80:20 vol./vol.). A potentiometric Study.

1990

Abstract A potentiometric study on the interaction at 25 °C and 0.15 mol dm −3 between large polyazacycloalkanes of the series [3 k ]aneN k and Zn(II) and Cd(II) ions in dmso:H 2 O (80:20 vol./vol.) is reported. The protonation behavior of the free macrocycles and coordination trends are compared with those previously observed in aqueous solution. The main features observed in the mixed solvent are: similar protonation behavior of the free polyamines, greater tendency to form binuclear and protonated complexes and a lower tendency to bear hydrolytic reactions.

Inorganic ChemistrySolventHydrolysisAqueous solutionChemistryInorganic chemistryPotentiometric titrationMaterials ChemistryProtonationPhysical and Theoretical ChemistryChemical equilibriumMedicinal chemistryIon

Parametric assessment of myocardial perfusion during interventional cardiac catheterization by means of X-ray densitometry-short-and long-term result…

1990

X-ray densitometric evaluation of digital subtraction angiocardiograms allows an assessment of myocardial perfusion by means of the parameter 'MEAN RISE TIME' (MRT), defined as the time from the onset of local myocardial contrast medium opacification to the point of maximum opacification. Best results are obtained when the response of that parameter is compared before and after stimulation of coronary flow by papaverine. A prolongation of this parameter, especially after papaverine, was indicative of an impairment of myocardial perfusion, when compared to the results of TL-201 scintigraphy. In 50 patients with single vessel coronary artery disease the results of MRT pre and post papaverine …

AdultMalemedicine.medical_specialtyCardiac Catheterizationmedicine.medical_treatmentCoronary DiseaseConstriction PathologicScintigraphyAbsorptiometry PhotonRecurrenceInternal medicineCoronary CirculationPapaverineMedicineHumansRadiology Nuclear Medicine and imagingLongitudinal StudiesAngioplasty Balloon CoronaryCardiac imagingCardiac catheterizationAgedPapaverinemedicine.diagnostic_testbusiness.industrySubtractionAngiography Digital SubtractionMiddle AgedContrast mediumCardiologyFemaleCardiology and Cardiovascular MedicinebusinessDensitometryPerfusionAngioplasty Balloonmedicine.drugInternational journal of cardiac imaging

Effect of granulocyte-macrophage colony-stimulating factor on neutropenia and related morbidity induced by myelotoxic chemotherapy.

1990

Abstract purpose: A phase Ib/II clinical study was undertaken to assess the efficacy of recombinant human (rh) granulocyte-macrophage colony-stimulating (GM-CSF) factor in attenuating neutropenia and associated morbidity caused by high-dose anticancer chemotherapy administered in the presence or absence of autologous bone marrow support. patients and methods: Twenty-two patients with various solid tumors and lymphoid neoplasias were treated with a single daily subcutaneous dose of rh GM-CSF (250/μg/m 2 ) 48 hours after receiving a second cycle of highly myelotoxic chemotherapy for a period of 10 days. Within-subject comparisons on neutropenia-related clinical and laboratory variables were m…

OncologyAdultMalemedicine.medical_specialtyNeutropeniaTime FactorsAdolescentmedicine.drug_classNeutrophilsmedicine.medical_treatmentAntibioticsNeutropeniaLeukocyte CountColony-Stimulating FactorsBone MarrowInternal medicineNeoplasmsAntineoplastic Combined Chemotherapy ProtocolsmedicineHumansIn patientGrowth SubstancesAgedBone Marrow TransplantationChemotherapybusiness.industryCancerGranulocyte-Macrophage Colony-Stimulating FactorGeneral MedicineMiddle AgedAutologous bonemedicine.diseaseRecombinant ProteinsAnti-Bacterial AgentsGranulocyte macrophage colony-stimulating factorImmunologyToxicityDrug EvaluationFemalebusinessmedicine.drugAgranulocytosisThe American journal of medicine

Saturation of deformation atN=60 in the Sr isotopes

1990

From the halflife oft 1/2=3.91 (16) ns for the 21 + state in100Sr a deformation parameter ofβ=0.40(1) has been derived. Within the given uncertainties, this value is equal to the recently determinedβ-parameters for98Sr and99Sr, indicating that in the Sr isotopes saturation of deformation is reached immediately at its onset well before neutron midshell. This behaviour is reflected by the “twin” character of98Sr and100Sr with identical features of their unperturbed ground-state rotational bands. These observations are discussed in terms of strong two-nucleon interactions.

Nuclear physicsPhysicsNuclear and High Energy PhysicsIsotopeNuclear fusionNeutronDeformation (meteorology)Atomic physicsSaturation (chemistry)Zeitschrift f�r Physik A Atomic Nuclei

Exchange rate dynamics in black markets

1990

Economics and EconometricsExchange rateEconomicsMonetary economicsGeneral Business Management and AccountingPublic financeJournal of Economics

Mast cell growth-enhancing activity (MEA) is structurally related and functionally identical to the novel mouse T cell growth factor P40/TCGFIII (int…

1990

We have previously shown that certain bone marrow-derived mast cell (BMMC) lines proliferate in response to a mast cell growth-enhancing activity (MEA) that is distinct from interleukin (IL) 3 and IL 4. Here we provide evidence that MEA is identical with the recently cloned mouse T cell growth factor P40. The evidence is as follows: (a) recombinant P40 displayed all the biological activities ascribed to MEA: it supported the growth of MEA-sensitive BMMC lines, it induced IL 6 secretion by these cells, and it enhanced survival of primary mast cell cultures; (b) highly purified MEA stimulated the growth of P40-dependent cell lines; (c) a rabbit monospecific antiserum directed against P40 spec…

medicine.medical_treatmentT-LymphocytesImmunologyBone Marrow CellsBiologyIn Vitro TechniquesBinding CompetitiveMicemedicineImmunology and AllergyAnimalsInterleukin 9Mast CellsGrowth SubstancesInterleukin 4Cell growthGrowth factorImmune SeraInterleukinsInterleukin-9Interleukinfood and beveragesMast cellCell biologyCytokinemedicine.anatomical_structureCell cultureImmunologyEuropean journal of immunology

Solution Properties of Polyelectrolytes. VI. Secondary Effects in Aqueous Size-Exclusion Chromatography

1990

Abstract An independent analysis of different operational variables in aqueous size exclusion chromatography of poly electrolytes has been carried out using a silica-based support. The effect of polyion concentration, pH and ionic strength on sodium polystyrenesulfonate calibration plots has been investigated. Finally, a novel semi-empirical model has been developed from thermodynamic considerations which relates the support effective pore volume to the polyelectrolyte molecular weight and qualitatively describes secondary effects.

ChromatographyAqueous solutionVolume (thermodynamics)Ionic strengthChemistrySodiumSize-exclusion chromatographyMolecular Medicinechemistry.chemical_elementElectrolytePolyelectrolyteJournal of Liquid Chromatography

1‐Oxa‐3‐cyclooctin

1990

1-Oxa-3-cyclooctyne According to an MNDO calculation, 1-oxa-cyclooctyne (13) and 1-oxa-3-cyclooctyne (14) are 8-membered heterocyclic ring systems with high steric energy (ring strain). On the basis of THF (1) and acetoacetic ester (4), a multi-step synthesis is described for 14. The triple bond is introduced in the last step by a thermal fragmentation of the 1,2,3-selenadiazole 12.

Inorganic ChemistrySteric effectsFragmentation (mass spectrometry)ChemistryStereochemistryAcetoacetic ester synthesisMNDOTriple bondRing (chemistry)Ring strainChemische Berichte

Induction of micronucleated and binucleate cells in Chinese hamster ovary (CHO) cells by cis-diamminedichloroplatinum (II): a morphological and morph…

1990

Abstract The mutagenicity and cytotoxicity of cis -diamminedichloroplatinum (II) (cisplatin) at doses of 5, 10 and 20 μg/ml in Chinese hamster ovary (CHO) cells have been examined. A morphological characterization of several cell types induced by cisplatin was carried out. The frequencies of both cells with micronuclei and binucleate cells as a time-dependent parameter have also been studied. Whilst the number of cells with micronuclei was found to decrease with time, the number of binucleate cells increased. The possible kinetic mechanism for the production of binucleate cells and cells with micronuclei is discussed. A morphometric analysis was also performed. The nuclear area in both trea…

Cell NucleusGeneticsCisplatinCis diamminedichloroplatinum iiCell typeMicronucleus TestsDose-Response Relationship DrugChinese hamster ovary cellNuclear areaBiologyToxicologyMolecular biologyCricetinaeMicronucleus testGeneticsmedicineAnimalsCisplatinCytotoxicityInterphaseCell DivisionCells CulturedAfter treatmentmedicine.drugMutation Research/Genetic Toxicology

Histological effects of He-Ne laser on the healing of experimental colon anastomoses in the rat

1990

Despite technical advances, the incidence of anastomotic leaks in elective colorectal surgery remains around 14%, Recent studies suggest that the use of low energy lasers may enhance wound healing in different tissues in a selective, nondestructive manner. Based on these findings we have attempted to provide experimental background on the histological effects of He-Ne laser during the early stages of healing in 70 colonic anastornoses performed on rats, The irradiation of the anastomoses by two doses of 3.6 J/cm produces an increase in the populations of round cells and fibroblasts of the scar tissue, an increase in new vessel formation and a significant improvement in epithelialization. Th…

medicine.medical_specialtyRound cellsPathologyMaterials scienceLow energyAnastomotic leaksScar tissuemedicineHe ne laserAnastomosisWound healingColorectal surgerySPIE Proceedings

Measurement of the4He-D2 mass difference

1990

A Penning ion trap spectrometer has been used to measure the modified cyclotron frequencies of trapped4He+ and D 2 + ions. The resonances were detected by a time of flight method after ejection of the ions from the trap. We obtain a mass differenceΔm (D2-4He) = 25600331(5)·10−9 amu in acordance with published values but with a reduced uncertainty.

PhysicsSpectrometerCyclotronAtomic and Molecular Physics and OpticsFourier transform ion cyclotron resonanceIonlaw.inventionNuclear physicsTime of flightDeuteriumlawMass spectrumIon trapAtomic physicsZeitschrift f�r Physik D Atoms, Molecules and Clusters

The Mu1 transposable element of maize contains two promoter signals recognized by the Escherichia coli RNA polymerase.

1990

The galactokinase (GalK) expression plasmid vector system pKO-1 has been used to screen for promoter elements in the maize transposable element Mu1 that function in Escherichia coli. Two transcriptional start points, named S1 and S2, were identified, which are located in the two direct repeats of the transposable element. This paper demonstrates that sequence elements exist in a plant transposable element which function as prokaryotic promotors.

Transposable elementTranscription GeneticMolecular Sequence DataRestriction MappingBiologymedicine.disease_causeZea mayschemistry.chemical_compoundRNA polymeraseGeneticsmedicineEscherichia coliDirect repeatInsertion sequenceCloning MolecularPromoter Regions GeneticMolecular BiologyEscherichia coliGeneticsExpression vectorBase SequencePromoterDNA-Directed RNA PolymerasesGalactokinasechemistryDNA Transposable ElementsMoleculargeneral genetics : MGG

13C nuclear magnetic resonance spectra of several podocarpane and cassane diterpenoids

1990

The 13C NMR spectra of several diterpenic derivatives having the podocarpane and cassane skeleton were recorded and interpreted. The most significant effects due to substituent orientation, B/C ring junction stereochemistry and conformational changes are briefly discussed.

chemistry.chemical_compoundNuclear magnetic resonancechemistryStereochemistrySubstituentChemical solutionGeneral Materials ScienceGeneral ChemistryNuclear magnetic resonance spectroscopyCarbon-13 NMRDiterpeneSpectral lineMagnetic Resonance in Chemistry

Calcium antagonist properties of cinnarizine, trifluoperazine and verapamil in guinea-pig normal and skinned trachealis muscle.

1990

In guinea-pig trachealis, depolarized by a K(+)-rich medium, Ca2+ (0.01-10 mM) caused concentration-related spasm. Verapamil (0.5-5 microM), cinnarizine (10-100 microM) and trifluoperazine (16-160 microM) each produced concentration-dependent antagonism of Ca2+ characterized by a rightward and downward displacement of the log concentration-effect curve for Ca2+. The rank order of potencies of these antagonists, measured as the IC75 against Ca2+ (10 mM)-induced contraction of depolarized trachea, was verapamil (5.6 microM) greater than cinnarizine (59 microM) greater than trifluoperazine (91 microM). In skinned trachea, verapamil in concentrations up to 100 microM did not modify the concentr…

MaleCinnarizineContraction (grammar)StereochemistryGuinea PigsPharmaceutical Sciencechemistry.chemical_elementTrifluoperazinePharmacologyCalciumIn Vitro TechniquesCinnarizinemedicineAnimalsPharmacologyAntagonistMuscle SmoothCalcium Channel BlockersTrifluoperazineTracheaMechanism of actionchemistryVerapamilTrachealis muscleVerapamilFemalemedicine.symptommedicine.drugThe Journal of pharmacy and pharmacology

Double beta-decay and su(4) symmetry

1990

The amplitude for ββ decay with 2ν emission is shown to be related to (p,n) and (n,p) reactions on the initial and final states, respectively. The suppression of both ββ and (n,p) reaction is connected, and its origin is discussed by referring to theSU(4) symmetry. From present data on the first ones, we estimate the forward (n, p) strength of relevance for the ββ problem. The interest of the experimental determination of this strength is emphasized. Assuming a perturbative breaking of theSU(4) symmetry, results are given for76Ge,82Se,128Te and130Te.

PhysicsParticle physicsAmplitudePhysics and Astronomy (miscellaneous)Double beta decayFísicaElementary particleField theory (psychology)Quantum field theoryEngineering (miscellaneous)Symmetry (physics)

The orientational glass state of argon:Nitrogen and cyanide mixed crystals

1990

Abstract Solid solutions of Ar:N 2 and ( KBr ) 1− x ( KCN ) x mixed crystals show a so-called orientational glass state where the orientations of the aspherical species, N 2 respectively CN - , are frozen in random patterns. The main experimental characteristics of this state and the pertinent theoretical concepts are discussed.

chemistry.chemical_compoundArgonchemistryCyanideInorganic chemistryAnalytical chemistrychemistry.chemical_elementGeneral Materials ScienceGeneral ChemistryCondensed Matter PhysicsOrientational glassNitrogenSolid solutionSolid State Ionics