showing 36 of ~574560 from 574555 documents

Immunohistochemical localization of polysialic acid in tissue sections: differential binding to polynucleotides and DNA of a murine IgG and a human I…

1990

For immunolocalization of alpha(2-8)-linked polysialic acid, which forms part of the neural cell adhesion molecule (N-CAM), two monoclonal antibodies, MAb735 and IgMNOV, were employed. Both antibodies have previously been shown to bind the extremely low immunogenic capsular polysaccharide of group B meningococci, which also consists of alpha(2-8) polysialic acid, but not to other, even closely related forms of polysialic acid. Despite the identical polysaccharide specificity of these two MAb, we observed marked differences of the staining pattern in tissue sections. We showed that these differences in immunostaining were due to the crossreactivity of IgMNOV with polynucleotides and DNA. MA…

Histologymedicine.drug_classCell Adhesion Molecules NeuronalPolynucleotidesAntibody AffinityEnzyme-Linked Immunosorbent AssayMonoclonal antibodyBinding CompetitiveImmunoglobulin Gchemistry.chemical_compoundMiceAntigenmedicineAnimalsHumansAntigensBrain ChemistrybiologyStaining and LabelingPolysialic acidBacterial polysaccharideAntibodies MonoclonalDNAMolecular biologyImmunohistochemistrySialic acidBiochemistrychemistryLiverImmunoglobulin Gbiology.proteinSialic AcidsNeural cell adhesion moleculeAnatomyDNA ProbesImmunostainingThe journal of histochemistry and cytochemistry : official journal of the Histochemistry Society

Muon capture in deuterium and the meson exchange current effect

1990

Abstract One-meson exchange current effect in reaction μ − + d → 2 n + v μ is calculated by using the weak axial current operator which satisfies the nuclear continuity equation up to the order 1 M 2 ( M is the nucleon mass). In the vector part of the weak nuclear interaction the vector-isovector pion exchange currents are also included. Their contribution is found to be non-negligible. The nuclear wave functions are generated from the Paris, Reid soft-core and Bonn potential models. Our result is compatible with the previous one, obtained with only the static axial exchange currents included.

PhysicsNuclear physicsNuclear and High Energy PhysicsPionContinuity equationDeuteriumMesonOperator (physics)Nuclear TheoryNuclear ExperimentNucleonWave functionMuon captureNuclear Physics A

Dynamic response of multiply connected primary-secondary systems

1990

The nodal equations of motion of the composite system are given in «total» and «relative» coordinates. In the framework of the component-mode synthesis method a coordinate transformation, here defined as an admissible one, is used to reduce the nodal equations of motion. This coordinate transformation is theoretically and numerically compared with the coordinate transformation usually used in the literature, which generally gives larger errors with respect to the former when a reduced number of nodes is considered

Transformation (function)Primary (astronomy)Coordinate systemMode couplingMathematical analysisEarth and Planetary Sciences (miscellaneous)Equations of motionGeometryGeotechnical Engineering and Engineering GeologyMathematics

Magnetic excitations and phase transition of CsFeBr3 in an external magnetic field

1990

In CSFeBr3 the Fe2+ ion with effective spin one has locally a singlet ground state (m=0). The antiferromagnetic interactions between neighbouring Fe-ions are too weak as compared with the anisotropy constant to introduce long range order in the absence of an external field. By inelastic neutron scattering we studied the magnetic excitations in an external magnetic field up to 5 Tesla applied along thec-axis. A linear Zeeman splitting was observed with a Lande factorg=2.4. The field renormalizes the dispersion curves in such a way that the exchange interaction has decreasing influence with increasing field. Theoretical calculations according to the excitonic model of Lindgard describe the ex…

PhysicsPhase transitionZeeman effectCondensed matter physicsField (physics)Critical phenomenaNeutron scatteringCondensed Matter PhysicsInelastic neutron scatteringElectronic Optical and Magnetic MaterialsMagnetic fieldsymbols.namesakesymbolsGeneral Materials ScienceSpin-½Zeitschrift f�r Physik B Condensed Matter

STATISTICAL ANALYSIS OF URBAN NOISE LEVELS

1990

Noisegeographygeography.geographical_feature_categoryAcousticsGeneral EngineeringEnvironmental scienceStatistical analysisUrban noiseUrban areaLe Journal de Physique Colloques

Mixed monolayers of natural and polymeric phospholipids: structural characterization by physical and enzymatic methods

1990

This study has focused on physical characterization and enzymatic hydrolysis of mixed monolayers of a natural phospholipid substrate and a polymerizable phospholipid analogue. Such a mixed system presents the possibility to stabilize model biomembranes, vary the molecular environment within the layer through polymerization and simultaneously examine these influences on monolayer structure. Phospholipase A2 was used here as a sensitive probe of the molecular environment within these mixed, polymerizable monolayers to complement information obtained from isotherm and isobar data. The results clearly show a strong influence of molecular environment on phospholipase A2 activity, even if differe…

Chemical PhenomenaPolymersBiophysicsPhospholipidBiochemistryPhospholipases Achemistry.chemical_compoundPhosphatidylcholineEnzymatic hydrolysisMonolayerOrganic chemistryPhospholipidsPhospholipase AMolecular StructureChemistry PhysicalHydrolysisTemperaturetechnology industry and agricultureSubstrate (chemistry)Membranes ArtificialCell BiologyPhospholipases A2MonomerchemistryPolymerizationPhosphatidylcholinesBiophysicsDimyristoylphosphatidylcholineBiochimica et Biophysica Acta (BBA) - Biomembranes

Vinblastine and interferon-alpha-2a regimen in the treatment of metastatic renal cell carcinoma.

1990

Thirteen patients with histologically proven advanced and/or metastatic renal cell carcinoma (RCC) were treated with vinblastine (Velbe, Eli Lilly, Sesto Fiorentino, Italy) and interferon-alpha-2a (Roferon-A, Roche, Milan). Eleven out of 13 patients were evaluable. Eighteen percent of patients had partial response, 46 % stable disease (SD), and 36 % progressive disease (PD). The mean survival of responders was 228+ days, whereas the patients showing SD and PD had a mean survival of 154+ and 107+ days respectively. Toxicity, including influenza-like syndrome, fever, neurological and gastrointestinal side effects, was generally mild. However, medication with paracetamol was required in 82 % …

OncologyAdultMaleCancer Researchmedicine.medical_specialtyInterferon alpha-2VinblastineGastroenterology03 medical and health sciences0302 clinical medicineStable DiseaseRenal cell carcinomaPartial responseInternal medicinemedicineHumans030212 general & internal medicineInterferon Alpha 2aCarcinoma Renal CellAgedbusiness.industryInterferon-alphaGeneral MedicineMiddle Agedmedicine.diseaseKidney NeoplasmsRecombinant ProteinsVinblastineRegimenOncology030220 oncology & carcinogenesisToxicityInterferon Type IDrug Therapy CombinationFemalebusinessProgressive diseasemedicine.drugTumori

Commutator anomalies and the Fock bundle

1990

We show that the anomalous finite gauge transformations can be realized as linear operators acting on sections of the bundle of fermionic Fock spaces parametrized by vector potentials, and more generally, by splittings of the fermionic one-particle space into a pair of complementary subspaces. On the Lie algebra level we show that the construction leads to the standard formula for the relevant commutator anomalies.

CommutatorHigh Energy Physics::Lattice58D30Statistical and Nonlinear Physics58B25Space (mathematics)Linear subspace58G35Fock spaceLinear map81D07Quantum mechanicsLie algebraGauge theoryAnomaly (physics)Mathematical PhysicsMathematical physicsMathematics81E13

A Phase I–II Study on the Toxicity and Therapeutic Efficacy of 5-Fluorouracil in Combination with Leucovorin and Cisplatinum in Patients with Advance…

1990

5-Fluorouracil (5-FU) has been the treatment of choice for colorectal carcinoma with an overall response rate of about 20%. Recent studies have shown that folate (LV) can increase 5-FU therapeutic efficacy, achieving about a 40% response rate without a clear impact on survival. Cisplatinum (CDDP) is usually inactive in colorectal carcinoma, but the association with 5-FU results in a synergistic antineoplastic effect. A phase I-II study was done to assess the maximally tolerated dose (MTD) of CDDP in association with 5-FU + LV. The MTD for CDDP was 20 mg/m2/wk in association with 5-FU 400-500 mg/m2/wk and LV 500 mg/m2/wk. WHO criteria were used for evaluation of both toxicity and response. I…

AdultMale0301 basic medicineOncologymedicine.medical_specialtyColorectal cancerNausea030106 microbiologyLeucovorinGastroenterology03 medical and health sciences0302 clinical medicineInternal medicineAntineoplastic Combined Chemotherapy ProtocolsHumansMedicinePharmacology (medical)In patientAgedPharmacologyCisplatinClinical Trials as Topicbusiness.industryMiddle Agedmedicine.diseaseDiarrheaInfectious DiseasesOncologyFluorouracil030220 oncology & carcinogenesisToxicityVomitingDrug EvaluationFemaleFluorouracilCisplatinmedicine.symptomColorectal Neoplasmsbusinessmedicine.drugJournal of Chemotherapy

Status of CP violation

1990

PhysicsNuclear and High Energy PhysicsParticle physicsCP violationAtomic and Molecular Physics and OpticsNuclear Physics B - Proceedings Supplements

2,9-Dimethylpicene: Synthesis, Mutagenic Activity, and Identification in Natural Samples

1990

Abstract 2,9-Dimethylpicene (2,9-DMPic) has been conveniently synthesized via a new route involving oxidative photocyclization of suitable substituted diarylethylenes and has been characterized by high-resolution 400-MHz 1H-NMR spectroscopy. Furthermore, 2,9-DMPic exhibits a typical line narrowed emission spectrum in n-decane matrix frozen at 15 K (Shpol'skii effect). Its unambiguous identification in a natural sample has been performed by this technique, providing strong evidence for the formation of this compound through aromatization of triterpenoid natural precursors. The mutagenicity of this naturally occurring methylated polycyclic aromatic hydrocarbon (PAH) has been examined in six h…

Matrix (chemical analysis)chemistry.chemical_classificationTriterpenoidPolymers and PlasticsChemistryStereochemistryOrganic ChemistryMaterials ChemistryAromatizationPolycyclic aromatic hydrocarbonSpectroscopyCarcinogenPolycyclic Aromatic Compounds

Photoproduction of neutral pions and low energy theorems

1990

PhysicsNuclear physicsNuclear and High Energy PhysicsLow energyPionNuclear Physics A

A dilute solution of garlands is equivalent to them-vector model

1990

We formulate a simple model of homogeneous garlands, which is valid for polymers, consisting of a thin main chain with large side groups placed equidistantly along the chain. The garlands continuouly change from selfavoiding walks,M=0, to random walks,m=1, to possibly ordered structures.

Pure mathematicsChain (algebraic topology)HomogeneousSimple (abstract algebra)General Materials ScienceField theory (psychology)Condensed Matter PhysicsRandom walkElectronic Optical and Magnetic MaterialsMathematicsZeitschrift f�r Physik B Condensed Matter

Evaluation of the flavor-changing vertexb→s+Husing the Breitenlohner-Maison-'t Hooft-Veltmanγ5scheme

1990

We reevaluate the one-loop-induced flavor-changing vertex {ital b}(bottom){r arrow}{ital s}(strange)+{ital H}(Higgs boson) using the Breitenlohner--Maison--'t Hooft--Veltman {gamma}{sub 5} scheme. Our result agrees with the result of previous calculations that employed a naive anticommuting {gamma}{sub 5} if one consistently employs left-chiral fermion fields in the perturbation expansion.

Vertex (graph theory)PhysicsParticle physicsComputer Science::Information RetrievalHigh Energy Physics::LatticeHigh Energy Physics::PhenomenologyQuark modelHiggs bosonB mesonElementary particleFermionQuantum field theoryBosonPhysical Review D

The pineal complex in Roman high avoidance and Roman low avoidance rats.

1990

Previous studies have shown that the pineal gland of Roman high avoidance (RHA/Verh) rats is larger than that of Roman low avoidance rats (RLA/Verh). In the present study measurement of enzyme activities (serotonin-N-acetyl-transferase, hydroxyindole-O-methyltransferase) revealed that pineals of RHA/Verh rats are twice as active in melatonin production than pineals of RLA/Verh rats. Indoleamine content was also higher in RHA/Verh rats, whereas noradrenaline content was the same in both lines. When values were expressed per mg protein, these differences disappeared except for N-acetyl-serotonin and noradrenaline which were higher or lower in RHA/Verh rats, respectively. Both lines had higher…

Acetylserotonin O-MethyltransferaseMaleendocrine systemmedicine.medical_specialtyArylamine N-AcetyltransferaseBiologyPineal GlandPinealocyteMelatoninPineal glandAcetyltransferasesInternal medicinemedicineAvoidance LearningAnimalsCircadian rhythmElectron microscopicBiological PsychiatryMelatoninRadioimmunoassayRats Inbred StrainsMethyltransferasesRatsPsychiatry and Mental healthMicroscopy ElectronEndocrinologymedicine.anatomical_structurenervous systemNeurologyAcetylserotonin O-methyltransferaseSynapsesNeurology (clinical)Dark phasehormones hormone substitutes and hormone antagonistsmedicine.drugJournal of neural transmission. General section

false

1990

It is shown that the block-like structure of the polyampholyte poly(methacrylic acid)-block-poly(1-methyl-4-vinylpyridinium chloride) considerably influences its conformational behaviour. This specific behaviour is explained by the formation of intra-macromolecular polyelectrolyte complexes stabilized by cooperative ionic contacts between acidic and basic units near the isoelectric point (i. e. p.). The structure of the block-polyampholyte at the i. e. p. is suggested to be close to the structure of non-stoichiometric polyelectrolyte complexes. The complex formation ability of the block-polyampholyte with respect to anionic, cationic, and nonionic polymers is also studied. By means of poten…

Poly(methacrylic acid)chemistry.chemical_compoundAqueous solutionMethacrylic acidChemistryPotentiometric titrationPolymer chemistrymedicineCationic polymerizationChlorideDissociation (chemistry)Polyelectrolytemedicine.drugDie Makromolekulare Chemie

Effects of vinblastine, leucine, and histidine, and 3-methyladenine on autophagy in Ehrlich ascites cells.

1990

The microtubule inhibitor vinblastine causes accumulation of autophagic vacuoles in many cell types. In hepatocytes, many of the accumulated vacuoles are nascent, which has been interpreted to suggest that vinblastine acts by inhibiting the fusion of hydrolase-containing lysosomes with early autophagic vacuoles. However, our previous results suggested that, in Ehrlich ascites cells, vinblastine causes accumulation mainly of older autophagic vacuoles (AVs). This study was undertaken to further characterize the mode of action of vinblastine in these cells. The vinblastine-accumulated AVs were quantified by electron-microscopic morphometry. In addition, the effects of inhibitors of autophagic …

Cell SurvivalPhagocytosisClinical BiochemistryVacuoleProtein degradationBiologyVinblastinePathology and Forensic MedicinePhagocytosisMicrotubuleLeucineLysosomemedicineAutophagyTumor Cells CulturedAnimalsHumansHistidineCarcinoma Ehrlich TumorChildMolecular BiologyAdenineAutophagyVinblastineCell biologyMicroscopy Electronmedicine.anatomical_structureBiochemistryLeucinemedicine.drugExperimental and molecular pathology

INTERACTION OF MACROMOLECULAR PRO-DRUGS WITH LIPID MODEL MEMBRANE - CALORIMETRIC STUDY OF 4-BIPHENYLACETIC ACID LINKED TO ALPHA,BETA-POLY(N-HYDROXYET…

1990

The effect of 4-biphenylacetic acid (BPAA) covalently linked to α,β-poly(N-hydroxyethyl)-dl-aspartamide (PHEA) on the thermotropic properties of dipalmitoylphosphatidylcholine (DPPC) liposomes was investigated by differential scanning calorimetry (DSC). Addition of increasing amounts of PHEA-BPAA adduct to a suspension of phospholipid vesicles modified the thermotropic gel-to-liquid crystalline phase transition by decreasing the enthalpy changes ΔH with concomitant broadening of the peak without variations in the transition temperature (Tm). These effects are interpreted in terms of a deep interaction of BPAA bound to the polymer with the apolar moiety of the lipid bilayer. The amount of dr…

LiposomeStereochemistryVesiclePhospholipidPharmaceutical ScienceThermotropic crystalCrystallographychemistry.chemical_compoundDifferential scanning calorimetrychemistryDipalmitoylphosphatidylcholinePhosphatidylcholinelipids (amino acids peptides and proteins)Lipid bilayer

Klinische Erfahrungen mit dem Kensey-Katheter-System - Komplikationen und Ergebnisse

1990

Fifteen procedures have been carried out in 14 patients using the Kensey rotation angioplasty system. Sixteen occlusions of the superficial femoral artery, with an average length of 10.2 cm (3 to 24 cm) and one artery with multiple stenoses were treated. The following results were obtained: creation of a lumen, with subsequent balloon dilatation in eight out of fifteen procedures; in two patients the vessels were occluded shortly after the procedure, due to complications (one obstructive plaque and one haematoma); five perforations, three dissections and one peripheral embolus. The total complication rate was 11 out of 15 cases, clinical improvement was obtained in six out of 15 cases.

medicine.medical_specialtySuperficial femoral arterybusiness.industrymedicine.medical_treatmentLumen (anatomy)Balloon dilatationSurgeryCathetermedicine.anatomical_structureAngioplastymedicineRadiology Nuclear Medicine and imagingComplicationbusinessPeripheral EmbolusArteryRöFo - Fortschritte auf dem Gebiet der Röntgenstrahlen und der bildgebenden Verfahren

Evaluation of Antimony, Cadmium and Lead Levels in Vegetables, Drinking and Raw Water from Different Agricultural Areas

1990

Abstract Lead and cadmium levels in edible vegetables and antimony, lead and cadmium in drinking and raw waters from three agricultural areas exposed to different levels of environmental pollution (1-high industrial pollution, 2-high urban pollution, 3-standard low industrial and urban pollution) are determined. The organic matter is destroyed by repeated attack with nitric acid. Cadmium and lead are determined by graphite furnace atomic absorption spectrometry (GFAAS) and antimony by hydride generation atomic absorption spectrometry (HGAAS). When the results obtained for three different areas are compared, differences between cadmium and lead contents in vegetables are observed. Waters are…

inorganic chemicalsPollutionchemistry.chemical_classificationCadmiumHealth Toxicology and Mutagenesismedia_common.quotation_subjectPublic Health Environmental and Occupational HealthSoil Sciencechemistry.chemical_elementEnvironmental pollutionPollutionAnalytical Chemistrylaw.inventionchemistryAntimonylawEnvironmental chemistryEnvironmental ChemistryOrganic matterRaw waterGraphite furnace atomic absorptionAtomic absorption spectroscopyWaste Management and DisposalWater Science and Technologymedia_commonInternational Journal of Environmental Analytical Chemistry

Haloperidol does not antagonize the effects of stress on aggressive behaviour in mice.

1990

The possibility that antipsychotic drugs antagonize the behavioural effects of stress on agonistic behaviour has been explored. Male mice of the OF.1 strain were subjected to the following treatments: 1) Immobilization stress (ten or twenty minutes in duration), 2) haloperidol (three doses) and 3) immobilization stress (ten minutes) plus haloperidol. Individually housed experimental animals confronted standard opponents (anosmic animals) in ten-minute encounters in a neutral cage. Encounters were videotaped and behaviour evaluated, assigning times allocated by subjects to eleven broad behavioural categories. The data show that stress markedly decreases attack behaviour, but haloperidol does…

MaleRestraint Physicalmedicine.medical_specialtyDose-Response Relationship Drugmedicine.medical_treatmentMale miceExperimental and Cognitive PsychologyMice Inbred StrainsDevelopmental psychologyAggressionBehavioral NeuroscienceMiceEndocrinologyInternal medicinemedicineHaloperidolAgonistic behaviourAnimalsHaloperidolRestraint stressAntipsychoticPsychologyArousalAgonistic Behaviormedicine.drugPhysiologybehavior

Group transfer and anionic polymerization: A critical comparison

1990

The mechanism of group transfer polymerization (GTP) of methacrylates in THF is investigated by using data on kinetics of homo- and copolymerization, polymer microstructure and molecular weight distribution. By comparison with corresponding data on anionic polymerization it is concluded that the mechanisms of monomer addition to the active chain end is very similar for both anionic and group transfer polymerization and that GTP is ionic in character. On the other hand, GTP uniquely is characterized by the existence of a catalyst exchange equilibrium. The position of this equilibrium determines the rates of polymerization, and the dynamics determine the molecular weight distribution.

Polymers and PlasticsChemistryOrganic ChemistryRadical polymerizationtechnology industry and agricultureCationic polymerizationChain transfermacromolecular substancesCondensed Matter PhysicsChain-growth polymerizationAnionic addition polymerizationPolymerizationPolymer chemistryMaterials ChemistryLiving polymerizationIonic polymerizationMakromolekulare Chemie. Macromolecular Symposia

Critical phenomena at surfaces

1990

Abstract The presence of free surfaces adds a rich and interesting complexity to critical phenomena associated with phase transitions occurring in bulk materials. We shall review Monte Carlo computer simulation studies of surface critical behavior in simple cubic Ising- and XY-models with nearest-neighbor interactions J in the bulk and Js at the surface. These studies allow the identification of various critical exponents and critical amplitude ratios involving both the critical behavior of local quantities and of surface excess corrections to the bulk. We consider both the “ordinary” transition (surface criticality controlled by the bulk) and the “special transition” (a multicritical point…

Statistics and ProbabilityPhase transitionCondensed matter physicsCritical point (thermodynamics)Critical phenomenaMulticritical pointIsing modelStatistical physicsRenormalization groupCondensed Matter PhysicsScalingCritical exponentMathematicsPhysica A: Statistical Mechanics and its Applications

Search for a neutral Higgs particle in the decay sequence $K^{0}_{L} \to \pi^{0}H^{0}$ and $H^{0} \to e^{+}e^{-}$

1990

Abstract We have searched for the sequence of decays K L 0 → π 0 H 0 and H 0 →e + e − at the CERN Super Proton Synchrotron (SPS), and have allowed for a non-zero H 0 lifetime. Three candidates have been seen, consistent with an expected background of 3.3. Limits on the branching ratio product in the range 10 −8 –10 −7 are presented as a function of the mass and lifetime of the H 0 . These can be used to restrict the neutral Higgs of the minimal standard model.

PhysicsNuclear and High Energy PhysicsSequenceParticle physicsRange (particle radiation)Large Hadron ColliderBranching fractionElementary particleSuper Proton SynchrotronStandard ModelNuclear physicsHiggs bosonHigh Energy Physics::ExperimentParticle Physics - Experiment

5-Oxo-1,4-dihydroindenopyridines: Calcium modulators with partial calcium agonistic activity

1990

The title compounds 4a-g were prepared by Knoevenagel reactions of 1,3-indandione (1) with the aromatic aldehydes 2a-g followed by cyclizing Michael addition of the products thus obtained with methyl β-aminocrotonate (3). The structures of products 4 were characterized by spectal data. Positive inotropic activities were observed on electrically stimulated, left atria of giunea pigs and these effects could be attributed to calcium agonism. On the other hand, barium chloride-induced contractions of guinea pig ileum were inhibited in a dose-dependent manner.

InotropeChemistryStereochemistryOrganic ChemistryMichael reactionAgonistic behaviourchemistry.chemical_elementBariumKnoevenagel condensationCalciumGuinea pig ileumJournal of Heterocyclic Chemistry

A dinuclear rhodium(III) complex with the N,N′-ethylenebis(salicylideneiminato) (salen) ligand in a bridging bis-bidentate mode of coordination. Crys…

1990

In this communication we describe the synthesis and crystal structure of the complex [{Rh(η 2 -(C 6 H 4 )PPh 2 )(η 2 -P(o-ClC 6 H 4 )Ph 2 )} 2 (salen)]-(SbF 6 ) 2 , showing the bridging configuration of the salen ligand

DenticitySchiff baseStereochemistrychemistry.chemical_elementCrystal structureRhodiumInorganic Chemistrychemistry.chemical_compoundCrystallographychemistryMetal salen complexesSalen ligandX-ray crystallographyMaterials ChemistryMoleculePhysical and Theoretical ChemistryInorganica Chimica Acta

(+)-α-Pinene in the defensive secretion ofNasutitermes princeps (Isoptera, Termitidae)

1990

The frontal secretion ofNasutitermes princeps consists of 89% diterpenes and 11% monoterpenes. In the samples studied, (+)-α-pinene, whose optical purity reaches 99.5%, accounts for more than 80% of the monoterpenic content.

PharmacologyPinenealpha-PineneMonoterpeneCell BiologyBiologyNasutitermes princepsbiology.organism_classificationTerpeneCellular and Molecular Neurosciencechemistry.chemical_compoundTermitidaechemistryBotanyMolecular MedicineSecretionDiterpeneMolecular BiologyExperientia

Effect of dantrolene sodium in isolated guinea-pig trachea.

1990

The effect of dantrolene sodium (3 microM-0.3 mM) on the spontaneous tone and responses to various contractile agonists was studied in isolated guinea-pig trachea. Dantrolene produced a concentration-related inhibition of the spontaneous tracheal tone, reaching a value of 94.8 +/- 4.8% of the relaxation induced by caffeine 10 mM. Removal of the epithelium did not affect the dantrolene-induced relaxation. Dantrolene did not alter the concentration-response curve for KCl and produced only small displacements of the concentration-response curves for CaCl2, acetylcholine and histamine, without affecting their maximal effects. Dantrolene dose relatedly inhibited the contraction induced by caffei…

MaleContraction (grammar)Guinea Pigschemistry.chemical_elementCalciumPharmacologyIn Vitro TechniquesDantrolene SodiumDantroleneDantrolenePotassium Chloridechemistry.chemical_compoundCalcium ChlorideCaffeinemedicineAnimalsPharmacologyCalcium channelCell MembraneMuscle SmoothAcetylcholineTracheachemistryAnesthesiaMuscle TonusFemaleCaffeineAcetylcholineHistaminemedicine.drugHistamineMuscle ContractionEuropean journal of pharmacology

Orientation, recognition, and photoreaction of nucleolipids in model membranes

1990

Amphiphiles with nucleobases and nucleosides as headgroups have been synthesized. Their surface behavior was investigated in monolayers at the air/water interface. The double chain nucleolipids form stable monolayers with nearly identical surface pressure-area diagrams, whereas the spreading behavior of the mono chain amphiphiles is dominated by the various nucleobase-headgroups. When measuring the interactions between nucleolipid monolayers and nucleobases (monomeric and polymeric ones), specific base-base effects could be observed: the complementary nucleobases solubilized in the subphase expand the monolayer more than the non-complementary ones. Photodimerization reactions of thymine-amp…

Polymers and PlasticsStereochemistrytechnology industry and agricultureSynthetic membraneNucleobaseDouble chainCrystallographychemistry.chemical_compoundColloid and Surface ChemistryMonomerMembranechemistrySolubilizationMonolayerAmphiphileMaterials ChemistryPhysical and Theoretical ChemistryColloid & Polymer Science

Reorientations and phase transitions in (Kr)1-x(CH4-nDn)x

1990

The condensed isotopic modifications of methane, CH4, CH2D2, and CD4 and their solutions with Kr were investigated using dielectric techniques. The polarizabilities were computed from the permittivities of the pure liquids. Phase diagrams of methane-krypton alloys were deduced in the liquid-solid coexistence region and for the low temperature phases (T<30 K). From the Curielaws, which described the permittivities of the (Kr)1-x(CH2D2)x mixed crystals, the permanent dioole moment of CH2D2 is calculated to be 4 mD. In the octopolar ordered phases of the solid solutions the effective dipole moments are enhanced significantly.

PermittivityPhase transitionMaterials scienceKryptonchemistry.chemical_elementDielectricCondensed Matter PhysicsMolecular physics530Electronic Optical and Magnetic MaterialsDipoleNuclear magnetic resonancechemistryKinetic isotope effectGeneral Materials SciencePhase diagramSolid solution

N14(γ,π+)14Cgsat photon energies of 230, 260, and 320 MeV

1990

The pion angular distribution for {sup 14}N({gamma},{pi}{sup +}){sup 14}C{sub g.s.} has been measured at photon energies of 230 and 260 MeV. These data are consistent with the trend of our earlier data at 200 and 320 MeV. Additional forward angle data were obtained at 320 MeV. The results are compared to several calculations based on the distorted-wave impulse approximation and on the delta-hole model. The data are best fit by the calculations of Tiator {ital et} {ital al}. which use the delta-hole model in the resonance channel. These calculations fit the 230 MeV data well and underestimate the 260 and 320 MeV data by about 25%.

PhysicsNuclear reactionNuclear and High Energy PhysicsPionPhotonMesonNuclear TheoryHadronBremsstrahlungElementary particleAtomic physicsNuclear ExperimentBosonPhysical Review C

Isolation of the DNA minisatellite probe MZ 1.3 and its application to DNA ‘fingerprinting’ analysis

1990

Abstract A minisatellite probe, MZ 1.3, detecting hypervariable fragment patterns was isolated from a human genomic library. A repetitive sequence of 27 bp length was identified which is contained in the probe approx. 40 times. The MZ 1.3 repeat shows variable homology of 53–73% to the repetitive sequence of the protein III gene of the bacteriophage M13 genome. Polymorphic restriction fragment patterns were found with MZ 1.3 using the enzymes Hinf I, BstN I, Hae III, Mbo I, PstI PvuII , and Rsa I. An average of 18 polymorphic fragments was observed using Hinf I as enzyme. The band sharing frequency after Hinf I digestion among unrelated individuals was determined to be 23.8 ± 7.2%. An examp…

Molecular Sequence DataRestriction MappingDNA SatelliteHomology (biology)Pathology and Forensic MedicineRestriction fragmentchemistry.chemical_compoundHumansGenomic libraryGeneRepetitive Sequences Nucleic AcidGeneticsGenomic LibraryBase SequencebiologyNucleotide MappingDNAMolecular biologyBlotting SouthernVariable number tandem repeatMinisatelliteDNA profilingchemistrybiology.proteinDNA ProbesLawPolymorphism Restriction Fragment LengthDNAForensic Science International

Transitions in Presence of Short Laser Pulses

1990

Accurate numerical calculations are carried out to investigate the validity of the two-state approximation in the case of resonant interactions between electromagnetic radiation and atoms . Short pulses are considered and the presence of the atomic spectrum is modelled by introducing a third, nonresonant, state . We show that the harmonics of the pulse profile may play a significant role in the dynamics of the process and may cause energy nonconserving transitions between the atomic states. © 1990 Taylor & Francis Ltd.

PhysicsSettore FIS/02 - Fisica Teorica Modelli E Metodi Matematicibusiness.industryLaserElectromagnetic radiationAtomic and Molecular Physics and OpticsPulse (physics)law.inventionOpticslawHarmonicsEmission spectrumAtomic physicsbusinessEnergy (signal processing)Journal of Modern Optics

Constraints on an additional Z′ gauge boson versus the W, the top and the Higgs masses

1990

Abstract We analyse the restrictions on the mass and the mixing of an additional Z′ gauge boson that follow from the recent LEP measurements taking into account standard model (SM) radiative corrections. We find that these restrictions depend sharply on the assumed values for the SM structural parameters, the most important of which are M w and m top . The constraints become stronger for lighter W and heavier top.

PhysicsNuclear physicsNuclear and High Energy PhysicsGauge bosonParticle physicsElectron–positron annihilationHigh Energy Physics::PhenomenologyHiggs bosonRadiative transferElementary particleMixing (physics)Standard ModelBosonPhysics Letters B

The GABAergic system of the dorsal cortex of lizards: a combined HRP-GABA immunohistochemistry study.

1990

Abstract γ-Aminobutyric acid (GABA)-like immunoreactive (GABA-LI) neurons were found throughout the mediolateral and rostrocaudal axis of the dorsal cortex. They were horizontal, vertical and multipolar cells, mainly distributed in layers 1 and 3. GABA-LI boutons were diffusely distributed in layers 1 and 3, as well as forming basket-like images around layer 2 pyramidal perikarya. Double labelling experiments indicate that GABA-LI cells are an origin of and a target for rostrocaudal intrinsic projections within the dorsal cortex.

Cerebral CortexGeneral NeuroscienceCentral nervous systemLizardsAnatomyHippocampal formationBiologyHorseradish peroxidaseDorsal cortexchemistry.chemical_compoundmedicine.anatomical_structurenervous systemchemistryCerebral cortexmedicinebiology.proteinGABAergicImmunohistochemistryAnimalsNeurotransmitterHorseradish Peroxidasegamma-Aminobutyric AcidNeuroscience letters

Theoretical rotational constants of MeCnN species

1990

Abstract By means of SCF HF “ab initio” calculations with STO-3G and 6-31G basis sets, the geometric parameters of methylcyanopolyynes (MeCnN n=3, 5, 7 and 9) have been obtained. B0=0.3748 GHz for MeC7N and B0=0.2708 GHz for MeC9N, with a STO-3G basis set, were obtained. Both species, unstable in the laboratory, are still undetected in the interstellar medium, although their existence is very probable.

Interstellar mediumchemistry.chemical_compoundCondensed matter physicsBasis (linear algebra)NitrileChemistryGaussian orbitalAb initioGeneral Physics and AstronomyRotational spectroscopyPhysical and Theoretical ChemistryMolecular physicsBasis setChemical Physics Letters