showing 36 of ~574560 from 574555 documents

Nonsymmetric Fourier transforming with an anamorphic system

1984

The idea of obtaining a nonsymmetric Fourier transform with crossed cylindrical lenses of different focal lengths is presented. The anamorphic rotation-variant system produces a scaled Fourier transform F(u,mv) of an object f(x,y), where m is a scaling constant. The system performs controlled angular magnification of an object spectrum. It is shown that the super resolution in one direction is gained by reducing the number of degrees of freedom of the optical message in the other. Experimental results are shown where the scaling constant m of up to 10 has been obtained.

Physicsbusiness.industryMaterials Science (miscellaneous)Degrees of freedomMagnificationIndustrial and Manufacturing Engineeringsymbols.namesakeOpticsFourier transformOptical transfer functionsymbolsFocal lengthCylindrical lensBusiness and International ManagementbusinessConstant (mathematics)ScalingApplied Optics

Self-instructed condensation of amino acids and the origin of biological information

1984

In contemporary cells biological information is largely stored in nucleic acids. Therefore, a prerequisite in many theories on the origin of cellular life is the pre-existence of self-replicating polynucleotides that had to be formed by abiotic processes on the prebiotic Earth. It is usually assumed that the spontaneous synthesis of a self-replicating polynucleotide could take place readily. However, serious stereochemical obstacles exist which make such a synthesis extremely improbable. Amino acids, on the other hand, which are abundantly formed in prebiotic simulation experiments, are relatively easily polymerized to macromolecules (protoproteins) that share with modern proteins many prop…

chemistry.chemical_classificationbiologyStereochemistryChemistryPrebioticmedicine.medical_treatmentSupramolecular chemistryCondensed Matter PhysicsAtomic and Molecular Physics and OpticsCellular lifeAmino acidBiochemistryPolynucleotideNucleic acidbiology.proteinmedicinePhysical and Theoretical ChemistryPolymeraseMacromoleculeInternational Journal of Quantum Chemistry

Improved method for quantitative analysis of vitamin K1i and vitamin K1 2,3-epoxide in human plasma by electron-capture gas-liquid capillary chromato…

1984

VitaminChromatography GasChromatographyChemistryElectron captureCapillary actionEpoxideStereoisomerismImproved methodVitamin K 1General Chemistrychemistry.chemical_compoundHuman plasmaHumansQuantitative analysis (chemistry)Journal of Chromatography B: Biomedical Sciences and Applications

Gonadotropic Therapy in Men with Hypogonadotropic Hypogonadism

1984

Many therapeutic regimens, differing in dose and duration, have been employed in the treatment of hypogonadotropic hypogonadism. This study presents the results from a regimen of hCG plus hMG plus testosterone combined treatment in 15 patients affected by selective hypogonadotropic hypogonadism. The patients were homogeneous in age (16–23 years), testicular size, aspermia, absence of prior hormonal treatment, and normal karyotype. They were administered 5000 IU of hCG plus 75 IU of hMG twice a week for two months and a single dose of depo-testosterone (250 mg) in the third month. This therapeutic plan was carried out continuously for eight three-month cycles (24 months). Sexual maturation a…

GynecologyAzoospermiamedicine.medical_specialtymedicine.drug_classSecondary sex characteristicbusiness.industryUrologyEndocrinology Diabetes and MetabolismUrologyAspermiamedicine.diseaseRegimenEndocrinologymedicine.anatomical_structureReproductive MedicineHypogonadotropic hypogonadismScrotummedicineGonadotropinbusinessTestosteroneJournal of Andrology

The influence of brassinosteroid on growth and parameters of photosynthesis of wheat and mustard plants.

1984

The growth response of wheat (Triticum aest. L.) and mustard seedlings (Sinapis alba L.) treated with 10(-6) mol · l(-1) brassinosteroid (BR) foliar spray was measured. BR-treatment resulted in a general promotion of plant growth. We found the accumulation of photosynthates to be stimulated in the treated plants, as indicated by enhanced fresh and dry weights of leaves and shoots. BR also promoted the synthesis of soluble proteins and soluble reducing sugars, whereas the chlorophyll content was hardly affected. CO(2)-fixation in vivo as well as the (in vitro) RubPC-ase activity of BR-treated leaves were enhanced. In the developing wheat leaves we detected no difference in the ratio fraction…

Plant growthChlorophyll contentPhysiologySinapisfood and beveragesPlant ScienceBiologyPhotosynthesisbiology.organism_classificationMustard Plantchemistry.chemical_compoundchemistryShootBotanyBrassinosteroidPoaceaeAgronomy and Crop ScienceJournal of plant physiology

Equal distribution of T-lymphocyte subpopulations in thymus and spleen cells of NZB and BALB/c mice

1984

NZB mice develop an autoimmune disease of unknown etiology. Since the detection of immunoregulatory T-cells it has been speculated that disbalances of these cells may be important in the course of the NZB disease. By utilization of monoclonal antibody defining immunoregulatory Lyt subsets and a FACS IV system we investigated whether differences in the number and/or marker densities of given subsets exist between NZB and the normal reference strain BALB/c. Newborn animals and animals up to 60 weeks of age were tested. No significant difference in the percentages nor in the marker densities of theta+, Lyt 1+, and Lyt 2+ cells was observed at any age or sex, neither in spleen nor in thymus. It…

Agingmedicine.medical_specialtymedicine.drug_classT-LymphocytesImmunologychemical and pharmacologic phenomenaSpleenThymus GlandMonoclonal antibodyBALB/cLeukocyte CountMiceRheumatologyInternal medicinemedicineAnimalsImmunology and AllergyDistribution (pharmacology)Autoimmune diseaseMice Inbred BALB CMice Inbred NZBbiologySignificant differenceT lymphocyteFlow Cytometrybiology.organism_classificationmedicine.diseaseRheumatologymedicine.anatomical_structureImmunologySpleenRheumatology International

L'enseignement supérieur au Bénin

1984

référence interne : 84002

Afrique[SHS.EDU]Humanities and Social Sciences/Education[SHS.EDU] Humanities and Social Sciences/EducationOrganisation de l'enseignementBéninEnseignement supérieur

Seminal plasma-induced suppression of the respiratory burst of polymorphonuclear leukocytes and monocytes.

1984

Summary: Based on recent findings indicating suppression of lymphocytic functions by seminal plasma (SP) we tested the effects of SP from men with normo- and oligozoospermia (n = 7, each) on the generation of luminol-enhanced chemiluminescence (CL) of polymorphonuclear leukocytes (PMN) and monocytes (Mo) stimulated in vitro with zymosan. We found a complete suppression of CL of PMN and Mo by undiluted SP's, 1,000-fold dilutions still induced ≥ 20 percent inhibition. There was no difference between normo- and oligozoospermic men in inhibition of CL both with PMN and Mo. Protein concentrations of SP's were closely the same; all SP were free of the complement components C4 and C3c. After dialy…

Malemedicine.medical_specialtyNeutrophilsUrologyPercent InhibitionMonocytesComplement componentschemistry.chemical_compoundEndocrinologyOxygen ConsumptionSemenInternal medicinemedicineHumansImmunosuppression TherapyMonocyteZymosanProteinsGeneral MedicineComplement System ProteinsOligospermiaMolecular biologyRespiratory burstEndocrinologymedicine.anatomical_structurechemistryGenital tractLuminescent MeasurementsAndrologia

Necking behavior of low-density polyethylene-isotactic polypropylene blends: A morphological investigation

1984

The tensile behavior of low-density polyethylene-isotactic polypropylene blends was investigated at room temperature. Neck formation and propagation along the whole length of the samples were observed for the whole range of composition. This behavior, which is not indicated by most data available in the literature, was examined in relation to sample morphology by scanning electron microscopy. The results of this investigation indicated some differences between the morphology of these materials and the morphology of blends which do not undergo necking propagation.

PolypropyleneMaterials scienceMorphology (linguistics)Polymers and PlasticsScanning electron microscopeGeneral Chemistrychemistry.chemical_compoundLow-density polyethyleneTensile behaviorchemistryTacticityMaterials ChemistryComposite materialNeckingTensile testingPolymer Engineering and Science

Preparation of 2,3-seco-5α-cholestane-2,3-diol and 4α-methyl-2,3-seco-5α-cholestane-2,3-diol and its reactions with o-nitrophenyl selenocyanate

1984

The reaction of 2,3-seco-5 alpha-cholestane-2,3-diol and 4 alpha-methyl-2,3-seco-5 alpha-cholestane-2,3-diol with o-nitrophenyl selenocyanate was studied. The diols were synthesized from cholesterol.

inorganic chemicalsMagnetic Resonance SpectroscopyChemical PhenomenaOptical RotationSpectrophotometry InfraredClinical BiochemistryDiolBiochemistrychemistry.chemical_compoundEndocrinologySpectrophotometryNitrilespolycyclic compoundsmedicineSecosteroidsOrganic chemistryMolecular BiologyPharmacologyintegumentary systemmedicine.diagnostic_testorganic chemicalsOrganic ChemistryNuclear magnetic resonance spectroscopyChemistrychemistryIndicators and ReagentsCholestaneCholestanolshormones hormone substitutes and hormone antagonistsSteroids

Synergistic effect of peplomycin in combination with bleomycin on L5178y mouse lymphoma cells in vivo.

1984

Studying the treatment of NMRI mice with ip injections of bleomycin (BLM) for 5 days we found an approximate LD50 of 35 mg/kg; the toxicity of peplomycin (PEP) was slightly higher (LD50: approximately 25 mg/kg). The effect of the two drugs on growth of L5178y mouse lymphoma cells in NMRI mice was examined. BLM alone caused at a concentration of 2.5 mg/kg an almost complete inhibition of tumor cell growth; the same effect was determined with 1 mg PEP/kg. At these concentrations the drugs caused an increase of the survival time of 110% (BLM) or 104% (PEP). Given in combination, one-sixth of the optimal doses yielded an 100% increase of the median survival time. These results indicate a signif…

Malemedicine.drug_classCell SurvivalAntibioticsPharmacologyBiologyBleomycinchemistry.chemical_compoundBleomycinMicePeplomycinIn vivoDrug DiscoveryAntineoplastic Combined Chemotherapy ProtocolsmedicineAnimalsLeukemia L5178PharmacologyLeukemia Experimentalurogenital systemCell growthMouse LymphomaBiological activityDrug SynergismchemistryToxicityImmunologyPeplomycinThe Journal of antibiotics

Day/night changes of pineal gland volume and pinealocyte nuclear size assessed over 10 consecutive days

1984

Previous studies aimed at elucidating day/night changes of pineal gland size and pinealocyte nuclear volume have yielded contradictory results. The aim of the present investigation was to examine the above parameters over a period of 10 successive days, at 6-hour intervals under a lighting regimen of LD 12:12 (7 a.m. to 7 p.m.). It was found that changes in pineal gland volume could not be correlated with the light/dark phases; instead, a rhythm with a two-day period was encountered. Pinealocyte nuclear volume, by contrast, showed clear circadian changes, exhibiting troughs during photophase and peaks during scotophase. In this experimental series, the karyometric results conformed to the m…

MalePeriodicitymedicine.medical_specialtyLightKaryometryPeriod (gene)BiologyPineal GlandPinealocytePineal glandRhythmInternal medicineTestismedicineAnimalsNuclear volumeCircadian rhythmBiological PsychiatryCell NucleusBody WeightRats Inbred StrainsOrgan SizeCircadian RhythmRatsPsychiatry and Mental healthmedicine.anatomical_structureEndocrinologyNeurologyVolume (thermodynamics)sense organsNeurology (clinical)Journal of Neural Transmission

Giorgio Fuà: Problemas del desarrollo tardío en Europa, Institució Alfons el Magnànim, Diputació Provincial de Valencia, 1983, 171 pp.

1984

Economics and EconometricsHistoryRevista de Historia Económica / Journal of Iberian and Latin American Economic History

Polymeric monolayers and liposomes as models for biomembranes. How to bridge the gap between polymer science and membrane biology?

1984

This contribution deals with the stabilization of membrane model systems, especially vesicles. The desired further biological functionalization of these stabilized polymeric membranes is possible via the incorporation of proteins. Addition of natural lipids to polymerizable membranes and degradation of the unpolymerized component after polymerization allows selective opening of otherwise stable compartments. Finally, first attempts are made to combine biological properties of natural cells and the durability of polymerized membranes via fusion of synthetic vesicles with natural cells.

chemistry.chemical_classificationLiposomeMembranePolymerizationchemistryVesiclePolymer chemistryMonolayerMembrane biologySurface modificationPolymerDie Makromolekulare Chemie

Inferior altitudinal hemianopia associated with a tumor in the posterior fossa: report of a case

1984

Altitudinal hemianopias may be related to chiasmatic involvement. A case in which horizontal inferior hemianopia is associated with a tumor in the posterior fossa producing a triventricular hydrocephalus is described. The visual field defect is interpreted as a consequence of the pressure by a dilated third ventricle upon the chiasmatic area.

Adultmedicine.medical_specialtyPosterior fossaOptic chiasmDermatologyHumansDilated third ventricleMedicineNeuroradiologyAltitudinal hemianopiaBrain Neoplasmsbusiness.industryNerve Compression SyndromesGeneral NeuroscienceGeneral MedicineAnatomyHemianopiasmedicine.diseaseeye diseasesVisual fieldSurgeryHydrocephalusPsychiatry and Mental healthmedicine.anatomical_structureCranial Fossa PosteriorOptic ChiasmHemianopsiaFemaleNeurology (clinical)businessThe Italian Journal of Neurological Sciences

Relative Inversion in der St�rungstheorie von Operatoren und ?-Algebren

1984

Pure mathematicsTopological algebraPseudodifferential operatorsGeneral MathematicsHomogeneous spacePerturbation theoryFréchet algebraMathematicsMathematische Annalen

Synthesis of 1H-imidazo[3′,4′:4,5]thieno[2,3-b]pyridines. A new ring system

1984

A facile and convenient synthesis of the title compounds is described, using as starting materials the 2-nitro-3-aminothieno[2,3-b]pyridines. Mass spectral data of the above mentioned compounds are briefly discussed.

chemistry.chemical_compoundAcetic acidchemistryBicyclic moleculeFormic acidOrganic ChemistryChemical reductionOrganic chemistryImideRing (chemistry)Spectral dataJournal of Heterocyclic Chemistry

Research and Its Utilization at the Institute for Educational Research, Jyvaskyla, Finland

1984

Abstract Kari, J. 1984. Research and Its Utilization at the Institute for Educational Research, Jyvaskyla, Finland. Scandinavian Journal of Educational Research 28, 1‐7. The article deals with research carried out at the Institute for Educational Research during the last ten years and compares it with other educational research undertaken in Finland in the 1970's. A systematic study of educational research was initiated by Professor O.K. Kyostio in the 1970's. Approximately one half of the financial resources of the Institute is received from educational authorities and the other half from the University of Jyvaskyla. When examined in relation to educational levels, the emphasis of the acti…

Medical educationSecondary educationHigher educationbusiness.industryPrimary educationResearch needsEducationEducational researchAdult educationEducational financePolitical sciencePedagogyNeeds assessmentbusinessScandinavian Journal of Educational Research

IR-und UV-spektroskopische Eigenschaften einer homologen Reihe von molekulareinheitlichen, 12gliedrige Ringe enthaltenden Leiteroligomeren

1984

The reactions of multiple acrylates of oligo[(hydroxyphenylene)methylene] s (2a–2f), strongly diluted in boiling benzene, with 2,2′-azoisobutyronitrile in a mole ratio of 1:10, were investigated. The elemental analysis and the determination of relative molar masses of the resulting products (3, 4, 5, 6a, 6b, 7a and 7b) demonstrate that their molecules contain two nitrile groups. These data, together with the IR and UV spectra, show that the products are molecularly uniform ladder oligomers with two 1-cyano-1-methylethyl groups on both ends.

chemistry.chemical_compoundEnd-groupMolar masschemistryNitrilePolymer chemistryInfrared spectroscopyMoleculeMethyleneBenzeneOligomerDie Makromolekulare Chemie

Surface Anisotropy in the Expansion Behavior of Laminated Quasi-Isotropic Composites

1984

Mesure a l'aide d'un extensometre des deformations thermiques superficielles de deux materiaux stratifies resine epoxy-fibre de graphite. Les resultats dependent de la direction de mesure, l'anisotropie superficielle associee est inversement proportionnelle aux dimensions de l'echantillon et proportionnelle au rapport d'anisotropie d'une lamelle isolee. Comparaison avec la theorie des stratifications

Surface (mathematics)Materials scienceMechanics of MaterialsMechanical Engineeringvisual_artMaterials ChemistryCeramics and Compositesvisual_art.visual_art_mediumThermal strainEpoxyComposite materialComposite laminatesAnisotropyJournal of Composite Materials

NEUTRINO OSCILLATION AND STELLAR COLLAPSE.

1984

PhysicsGravitational collapseGeneral EngineeringAstrophysicsNeutrino oscillation

On a projective representation of chain geometries

1984

We define a distance d on the set of r-spaces of an n-space. By the transfer of d to the GrasmannianG=G(n, r) we obtain a distinguished class of normal rational curves of order 1, the “1-distance lines’, 1=1,..., r, which are in 1–1-correspondence to the so-called “generalized reguli of type (r, 1)”.

Set (abstract data type)Discrete mathematicsTransfer (group theory)Class (set theory)Pure mathematicsChain (algebraic topology)Order (group theory)Geometry and TopologyType (model theory)Rational normal curveProjective representationMathematicsJournal of Geometry

Estimating the length of minimal spanning trees in compression of files

1984

Compression of a formatted file by a minimal spanning tree (MST) is studied. Here the records of the file are considered as the nodes of a weighted undirected graph. Each record pair is connected in the graph and the corresponding arc is weighted by the sum of field lengths of those fields which differ in the two records. The actual compression is made by constructing an MST of the graph and by storing it in an economic way to preserve the information of the file. The length of the MST is a useful measure in the estimation of the power of the compression. In the paper we study upper bounds of this length, especially in the case where the field lengths of the different fields may vary. The u…

Discrete mathematicsSpanning treeComputer Networks and CommunicationsApplied MathematicsShortest-path treeMinimum spanning treeConnected dominating setCombinatoricsComputational MathematicsGraph (abstract data type)Undirected graphSoftwareMathematicsofComputing_DISCRETEMATHEMATICSMathematicsMinimum degree spanning treeBIT

Prognostic value of blood lactate in critically ill patients

1984

Hyperlactatemia is frequently observed in critically ill patients. A correlation of blood lactate concentrations and outcome of patients has been proven in circulatory shock, circulatory arrest, acute myocardial infarction, acute hypnotic drug poisoning and severe pancreatitis. However, the prognostic relevance of hyperlactatemia yields from statistical examinations in larger groups of patients. It should not be misused as a reliable prognostic sign in the individual patient, but is of high value in comparing groups of patients. In individual patients, hyperlactatemia is a useful indicator pointing to the severity of illness and to superimposed complications. Blood lactate is of considerabl…

medicine.medical_specialtyMyocardial InfarctionEmergency NursingSeverity of illnessmedicineHumansHypnotics and SedativesLactic AcidMyocardial infarctionIntensive care medicineMonitoring PhysiologicAcidosisCritically illbusiness.industryPoisoningShockPrognosismedicine.diseaseHeart ArrestIntensive Care UnitsPancreatitisShock (circulatory)Acute DiseaseCirculatory systemLactatesEmergency MedicinePancreatitisHyperlactatemiamedicine.symptomAcidosisCardiology and Cardiovascular MedicinebusinessResuscitation

Electrophysiological investigations on the central innervation of the rat and guinea-pig pineal gland

1984

The possible influence of central nervous structures on the electrical activity of single pineal cells was investigated in rat and guinea-pig. In the rat electrical stimulation of the hippocampal formation elicited both single cell responses with different latencies and mostly long-term excitations in single pineal cells, while stimulation of the habenular nuclei caused clear orthodromical responses with different latencies, alterations in the rate of spontaneous electrical activity and evoked discharges of "silent" units. In the guinea-pig electrical stimulation of the paraventricular nucleus influenced predominantly cells in the deeper layers of the posterior part of the pineal gland. Ele…

MaleSuperior Colliculiendocrine systemmedicine.medical_specialtyGuinea PigsCentral nervous systemBiologyHippocampusPineal GlandSynaptic TransmissionGuinea pigPineal glandDiencephalonInternal medicineNeural PathwaysmedicineAnimalsEvoked PotentialsBiological PsychiatryBrain MappingSuperior colliculusInferior ColliculiRatsPsychiatry and Mental healthElectrophysiologymedicine.anatomical_structureEndocrinologyHabenulaNeurologyHypothalamusThalamic NucleiNeurology (clinical)Paraventricular Hypothalamic NucleusJournal of Neural Transmission

Copolymers with ordered chemical structure

1984

Copolymers with well defined sequences can be obtained for instance by ring-opening polymerization of selected acetals. In this way regular copolymers of formaldehyde and ethylenoxide of the following structure are available2. In the same way some other copolymers with formaldehyde units were obtained. Of special interest are unsaturated polyacetales; for instance3 They can be modified by chemical reactions, for instance by hydrogenation, addition of bromine, iodine isocyanate or epoxidation. Recently a bicyclic unsaturated cycloacetal was prepared and polymerized4 Branched copolymers with a definite number of uniform sidechains are prepared by N-alkylation of polyamides5 The dependence of …

chemistry.chemical_classificationchemistry.chemical_compoundCrystallinitychemistryPolymerizationPolymer chemistryCopolymerSide chainPolymerIsocyanateAlkylPolydiacetylenesDie Makromolekulare Chemie

UV-Photometrische Analyse kationisch erzeugter Polystyrole, 2. Quantitative Bestimmung von Endgruppen in Polystyrolen, dargestellt mit Acylperchlorat…

1984

Acyl perchlorates generated in styrene without a solvent by acyl chlorides and silver perchlorate gave polystyrenes with covalently bonded acyl groups. In order to gain secured values their number average relative molecular masses (Mn) were determined by different methods. The polystyrenes could be hydrogenated with hydrogen and Raney nickel at room temperature and under atmospheric pressure without attacking the phenolic nuclei. In addition IR data and a UV absorption at 294 nm of the polystyrenes revealed the presence of and olefinic bond, which was also found in a polystyrene obtained by polymerisation with perchloric acid. Also the quantitative evaluation of the hydrogeneation by UV abs…

chemistry.chemical_compoundPerchloratechemistryPolymer chemistryPerchloric acidPolystyreneAbsorption (chemistry)Silver perchlorateRaney nickelAcyl groupStyreneDie Makromolekulare Chemie

L'enseignement supérieur au Cameroun

1984

référence interne : 84003

AfriqueCameroun[SHS.EDU]Humanities and Social Sciences/Education[SHS.EDU] Humanities and Social Sciences/EducationOrganisation de l'enseignementEnseignement supérieur

Organotin(IV) derivatives of the ambidentate ligand 2-thiouracil. Infrared, Mössbauer, 1H and 13C NMR studies

1984

Abstract Complexes Bu 2 n Sn(s 2 UraH −2 and [Me 2 SnOH] 2 (s 2 UraH −2 have been synthesized. Comparison of infrared spectra of the solid complexes with spectra of s 2 Ura and (PhHg) 2 (s 2 UraH −2 complex and point charge calculations (Mossbauer spectra) allow assignment of structures for the complexes of this ambivalent ligand. Polymeric structures are proposed for the complexes in the solid state, where the organometallic moieties are bonded to exocyclic S and N(3) atoms of the dianionic base, with formation of a four-membered chelate ring for Bu 2 n Sn(s 2 UraH −2 ). For [Me 2 SnOH] 2 (s 2 UraH −2 , 1 H and 13 C NMR data suggest retention of penta-coordination in trifluoacetic acid sol…

chemistry.chemical_classificationLigandChemistryStereochemistryInfrared spectroscopyCarbon-13 NMRRing (chemistry)Inorganic ChemistryCrystallographyMössbauer spectroscopyMaterials ChemistryMoleculeChelationPhysical and Theoretical ChemistryInorganic compoundInorganica Chimica Acta

Electro-Hydrodynamic Instabilities in Main Chain Thermotropic Liquid Crystalline Polyesters

1984

Abstract We have investigated the response behavior of the thermotropic nematic polymer, DDA-9, in an electric field. DDA-9 is composed of regularly alternating moieties and flexible spacers. At a critical threshold voltage, dependent on molar mass, these polymers show the onset of instability. The appearance of a (non-fluctuating) striped pattern (Williams domains) is shown and the time of formation and relaxation of these patterns is investigated as a function of applied Voltage.

Polyesterchemistry.chemical_classificationMolar masschemistryChemical physicsLiquid crystalElectric fieldRelaxation (NMR)Polymer chemistryPolymerThermotropic crystalInstabilityMolecular Crystals and Liquid Crystals

17 beta-carboxamide steroids: highly effective inhibitors of the phytohaemagglutinin mediated blastogenesis of normal human peripheral lymphocytes.

1984

Several novel 17 beta-carboxamide analogues of dexamethasone were synthesized. The common precursor, 9-fluoro-16 alpha-methyl-11 beta,17-dihydroxy-3-oxo-1,4-androstadiene-17 beta-carboxylic acid, did not bind to the glucocorticoid receptors of rat liver and human spleen tumours. In addition, no inhibition of the mitogen-induced blastogenesis of cultured human peripheral lymphocytes was observed. The 17 beta-carboxamide analogues, however, bound with similar affinities to the glucocorticoid receptors of both tissues. They inhibited the mitogen-induced blastogenesis of peripheral lymphocytes, showing the same potency and same order of binding affinity as the natural glucocorticoids.

Malemedicine.medical_specialtyChemical Phenomenamedicine.drug_classClinical BiochemistryeducationCarboxamideBiologyIn Vitro TechniquesLymphocyte ActivationBinding CompetitiveDexamethasoneGlucocorticoid receptorCytosolReceptors GlucocorticoidInternal medicinemedicinePotencyAnimalsHumansPhytohemagglutininsBeta (finance)GlucocorticoidsDexamethasonePhytohaemagglutininBiochemistry (medical)Biological activityRats Inbred StrainsGeneral MedicineDNAPeripheralRatsChemistryEndocrinologyLiverbiology.proteinmedicine.drugThymidineJournal of clinical chemistry and clinical biochemistry. Zeitschrift fur klinische Chemie und klinische Biochemie

The rheological behavior of HDPE/LDPE blends 4. Instability phenomena in capillary flow

1984

Experimental data, relative to instability phenomena in capillary flow, have been collected for HDPE/LDPE blends already characterized from a rheological viewpoint. The data comprise morphological observations as well as the determination of critical parameters as a function of the blend composition and of the processing conditions.

Materials sciencePolymers and PlasticsCapillary actionMineralogyGeneral ChemistryCondensed Matter PhysicsVelocity shearInstabilityLow-density polyethyleneRheologyCritical parameterMaterials ChemistryShear stressHigh-density polyethyleneComposite materialPolymer Bulletin

false

1984

A dimeric biradical •M plays a central role in the initiation of the spontancous polymerization of methyl methacrylate (M1). Besides the initiation step by chain transfer reaction, a change of the multiplicity of ˙M seems to be of importance. Evidence is given by heavy atoms in the solvent or in an inert gas atmosphere, leading to an acceleration of the overall polymerization rate. The observed effect is related to the atomic number of the respective heavy atom. Measurements of the temperature dependence of the effect for carbon tetrachloride show that — as expected — no activation energy is needed for this reaction step. The results are summarized in a reaction scheme for the initiation me…

chemistry.chemical_compoundReaction mechanismchemistryPolymerizationReaction stepRadical polymerizationPolymer chemistryLiving polymerizationChain transferSolution polymerizationMethyl methacrylatePhotochemistryDie Makromolekulare Chemie

Small angle scattering from oriented latent nuclear tracks

1984

Abstract Using X-ray and neutron small-angle scattering we studied the defects in mica created by irradiation with uranium ions delivered from the UNILAC accelerator at GSI (Darmstadt, Germany). The defects are regions of reduced density and are best described as cylinders with Gaussian radial density distribution. Scaling laws are given for the time development and the energy dependence of the track parameters.

PhysicsNuclear and High Energy PhysicsScatteringGaussianchemistry.chemical_elementUraniumIonNuclear physicssymbols.namesakechemistrysymbolsPhysics::Accelerator PhysicsNeutronIrradiationMicaSmall-angle scatteringNuclear ExperimentInstrumentationNuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms

false

1984

PolymerizationChemistryN-Butyl methacrylateCopolymerOrganic chemistryGas chromatographyPyrolysisQuantitative analysis (chemistry)Die Makromolekulare Chemie, Rapid Communications

The effects of a number of short-term exogenous stimuli on pineal serotonin-N-acetyltransferase activity in rats

1984

The present study deals with the question as to what extent the sympathetically innervated rat pineal gland is affected by a number of short-term exogenous stimuli given during day-time, as assessed by measuring pineal serotonin-N-acetyltransferase activity (NAT) which is directly proportional to melatonin formation. In male Sprague-Dawley rats kept under LD 12:12 pineal NAT was statistically significantly depressed by physical immobilization for 2 hours, swimming for 15 min in water of 10 and 30 degrees C, exposure for 2 hours to cold (5 degrees C) or heat (40 degrees C), noise (90 db) for 2 hours and hunger for 17 hours. An increase in NAT was noted after swimming for 15 min in water of 2…

Maleendocrine systemmedicine.medical_specialtyFood deprivationHot TemperatureArylamine N-AcetyltransferaseHypoglycemiaBiologyPineal GlandThirstRat Pineal GlandImmobilizationAcetyltransferasesStress PhysiologicalInternal medicinemedicineAnimalsInsulinSwimmingBiological PsychiatryNormal rangeAnestheticsWater DeprivationRats Inbred StrainsPhysical Immobilizationmedicine.diseaseHypoglycemiaRatsCold TemperaturePsychiatry and Mental healthEndocrinologyMelatonin formationNeurologyNeurology (clinical)medicine.symptomSerotonin N-acetyltransferase activityFood DeprivationNoiseJournal of Neural Transmission