showing 36 of ~574560 from 574555 documents
Effects of chlorpromazine and some of its metabolites on the EEG and on dopamine metabolism of the isolated perfused rat brain.
1979
Abstract The study concerned the effects of chlorpromazine (CPZ), monodesmethyl-chlorpromazine (NOR1-CPZ), didesmethyl-chlorpromazine (NOR2-CPZ), and chlorpromazine-N-oxide (CPZ-NO) on the EGG and on dopamine metabolism of the isolated perfused rat brain. Isolated brains were perfused with 100 ml of a perfusion medium containing 30% bovine red cells (v/v), 2 g bovine serum albumin, 14 mM glucose as well as one of the agents in a concentration of 10 μM. The main dopamine metabolite homovanillic acid (HVA) was measured fluorimetrically in the striatum of the isolated brain. The EGG was recorded by two symmetrical bipolar leads from the parietal regions at various times during the 30 min perfu…
Aggregation of sponge cells. Isolation and characterization of an inhibitor of aggregation receptor from the cell surface.
1979
From the cell membranes of the sponge Geodia cydonium a component was isolated and purified which inhibits the aggregation factor isolated from the same source; the component was termed anti-aggregation receptor. This molecule was characterized as a glycoprotein (54% neutral carbohydrate) and its molecular weight is in the range of 180,000 One biological site of the anti-aggregation receptor was determined to be D-galactose. Indirect evidence presented seems to indicate that this molecule is present in an active form in aggregation-deficient cells and absent in aggregation-susceptible cells.
Synthesis of a new bridgehead nitrogen heterocyclic system. Pyrrolo [2,1-f]-1,2,4-triazine derivatives
1979
1-Ureidopyrroles of type 6a,b prepared by the general method previously described (2), readily cyclized under basic conditions giving pyrrolo [2,1-f]-1,2,4-triazine-2,4(1H, 3H)dione derivatives.
A large-area modular electromagnetic shower detector for the CERN intersecting storage rings
1979
The authors describe the design and performances large-area (13 m/sup 2/) shower detector built for an experiment at the CERN ISR to detect electrons and gamma rays with energies up to 4 GeV. The main characteristics of the detector are: a) linearity of the energy response from 0.5 to 4 GeV; b) good energy, time and space resolutions; c) modularity of the mechanical assembly; d) low cost of construction. (3 refs).
Hypophysäre/Ovarielle Wirkstoffe
1979
A multi-reading method for dosimetric TL measurements with CaSO4:Dy phosphors
1979
Abstract A technique of dosimetric TL measurement for CaSO 4 :Dy phosphors is proposed. It is based on the results obtained in previous works, in which an approximately multi-Gaussian energetic distribution of the traps associated with the dosimetric peak and a different supralinear behaviour of the Gaussians were found. A single dosimeter is read a number of times by successive heating cycles which, starting always from room temperature, reach higher and higher final temperatures; in this manner it is possible to obtain consistent information on the dose several times. The drawback of the usual TL measurements, that is the total emptying of the dosimeter during one measurement, is then avo…
Evaluation of different similarity indices as measures of succession in arthropod communities of the forest floor after clear-cutting.
1979
Communities of spiders (Araneae) and beetles (Coleoptera) living in the soil and litter of clear-cut areas were compared with those of intact forest stands. Sixteen different indices of similarity were tested on three sets of material: spiders and beetles examined during one year in three clear-cut areas felled 3, 6 and 9 years earlier, and spiders in one clear-cut area examined during 7 successive years after felling. Other sources of evidence showed that succession in the spider community was divergent for at least 7 years after felling. The indices that seemed to express the changes best were: (1) Kendall's rank correlation test, (2) the Bray-Curtis measure, (3) Renkonen's percentage sim…
Beam blowup in race track microtrons
1979
Abstract Beam blowup of the special kind to be expected with race track microtrons is investigated using a simplified model. A worst case analytical estimation formula is briefly derived. Further, the results of a large number of numerical computations are communicated and it is tried to compress these results to a simple empirical estimation formula. Finally, microwave measurements of BBU shunt impedances and some methods to overcome BBU are briefly discussed.
Spherical solid model for muon and hydrogen in metals
1979
The spherical solid model and the spin density functional formalism have been applied to calculate the screening of a positive point charge at different lattice sites in Al, Na and Cu. Results are obtained for the Knight shift, the electric field gradient, the heat of solution and the diffusion barrier. It is found essential to use the spin-polarised form to evaluate the Knight shift, especially at low metallic densities and for impurities with a high nuclear charge. Both the Knight shift and the electric field gradient are found to be markedly different for substitutional and interstitial positions. The calculated heat of solution of hydrogen is lowest for the octahedral position in FCC Al…
Electromechanical delay in skeletal muscle under normal movement conditions.
1979
Electromechanical delays (EMD), the time from onset of EMG activity to change in acceleration or deceleration of the forearm, were studied in concentric and eccentric contractions of biceps and triceps brachii muscles. Horizontal flexion and extension movements were performed at varying speeds by 10 subjects. EMD time in concentric contractions for biceps was 41 +/- 13 ms and for triceps was 26 +/- 11 ms and was not influenced by the velocity of the movement. In eccentric contractions at the slow velocity the biceps EMD time was 38 +/- 13 ms and shortened to 28 +/- 10 ms at the faster velocity. The eccentric triceps EMD, however, was not significantly altered by movement velocity and averag…
Toxicity of 4-chloro-o-cresol to fish. Light microscopy and chemical analysis of the tissue
1979
Properties of the F0F1 ATPase Complex from Rhodospirillum rubrum Chromatophores, Solubilized by Triton X-100
1979
1. A cold-stable oligomycin-sensitive F0F1 ATPase complex from chromatophores of Rhodospirillum rubrum FR 1 was solubilized by Triton X-100 and purified by gel filtration. 2. The F0F1 complex is resolved by sodium dodecyl sulfate electrophoresis into 14 polypeptides with approximate molecular weights in the range of 58000--6800; five of these polypeptides are derived from the F1 moiety of the complex which carries the catalytic centers of the enzyme. 3. The purified F0F1 complex is homogeneous according to analytical ultracentrifugation and isoelectric focusing. 4. The molecular weight as determined by gel filtration is about 480 000 +/- 30 000. S020,w is 1.45 +/- 0.1 S and the pI is 5.4. 5…
Muscle strength and muscle characteristics in monozygous and dizygous twins.
1979
Muscle strength and electrical activity were investigated on 31 pairs of young male and female monozygous (MZ) and dizygous (DZ) twins. The measurements included leg forces, force-time, running velocity, muscular power, maximal integrated electromyographic activity (IEMG) and chronaximetry of the quadriceps muscle group. In each parameter the intrapair variance was computed and the differences were tested between the MZ and DZ twins. The variance ratio (MZ vs. DZ) was statistically significant only for muscular power confirming an earlier finding which has demonstrated a genetic component for the variable. In addition to the various performance variables several key enzymes involved in ATP …
Toxicity of 5- chloro- 3- methyl- catechol to rat: Chemical observations and light microscopy of the tissue
1979
5-chloro-3-methyl-catechol was first time described by GAUNT and EVANS (1961) as a metabolite of MCPA (4-chloro-2-methylphenoxyacetic aci~which is the most widely used herbicide in the Nordic countries. The toxicity of the metabolite 5-chloro-3-methylcatechol bas hot been studied so far. Other catechols like 3,5dichlorocatechol has been shown to be a metabollte of 2,4-D (BOLLAG et ai. 1968a, BOLLAG et ai. 1968b), and it has been proven to be toxic to cells by HORVATH (1971). The catechols are metabolized by bacteria finally to muconic semialdehyde (HORVATH 1970, HORVATH and ALEXANDER 1970). In this work the toxicity of 5-chloro-3-methyl-catechol to maie rats was studied in acute and subchro…
Testing of a constitutive equation with free volume dependent relaxation spectrum
1979
A model of non-linear viscoelasticity with relaxation times dependent upon free volume is here proposed. The free volume is related to the isotropic part of the stress tensor by means of a simple differential equation. The model predictions are compared with a large amount of experimental results taken on polymeric melts or concentrated solutions and reported in the literature. The single parameter of the model is determined, within each set of data, by fitting of the viscosity curve. A satisfactory agreement is obtained with data taken under both elongation and shear for which also the relaxation behavior after single and double strain steps is considered.
Differential effect of the enantiomers of phenprocoumon and warfarin on the vitamin K1-epoxide/vitamin K1 ratio in rat plasma.
1979
Le diatomee bentoniche del porto di Palermo
1979
Abstract Benthic diatoms in the harbour of Palermo (Sicily).—The first results of a systematic investigation on the benthic diatoms on the fouling settlements, at four selected sites in the harbour of Palermo, are reported. Samples of comparable areas have been examined either on the fouling of vertical walls of the wharfs or on asbestos panels vertically submerged at the same place for at least eighteen months. Seventy-seven species have been found. No marked taxonomic difference is evident between the populations on the stoneworks and those on the panels.
A Simple “Plastic Bag” Technique for Visible Spectra of Solid Metal Complexes
1979
The techniques commonly used to study the visible spectra of transition metal complexes in the solid state involve diffuse reflectance from the powdered sample or transmission through a mull of the compound in mineral oil on filter paper. Pressed KBr (for anhydrous compounds) and AgCl (for compounds containing water or other highly polar ligands) disk techniques have been used even for low temperature spectra. All of the transmission techniques mentioned are based on mixing the sample with another compound which may induce changes in the compound under study via chemical reactions. Air- and water-sensitive complexes also need special care. These interferences may be reduced by the use of th…
New synthesis of some 1,2,5-benzothiadiazcpinc 1,1-dioxide derivatives. I
1979
2-Nitrobenzenesulfonyl chloride reacts with ω-aminoacetophenone and 4-amino-3,5-dimethyl-isoxazole to give 3 and 7, respectively. Reduction of 3 with zinc powder and acetic acid afforded the 2,5-dihydro- and 2,3,4,5-tetrahydro-1,2,5-benzothiadiazepine I,1-dioxide derivatives (4 and 5). Catalytic hydrogenolysis of 7 and successive cyclization of the intermediate 8 gave the 3-ace-thyl-2,5-dihydro-4-methyl-1,2,5-benzothiadiazepine 1,1-dioxide (9). The structures were assigned on the basis of correct elemental data and spectroscopic evidences.
The Isomeric 9/2+and the Lowest 7/2-State in the Weakly Deformed N = 89 Nuclei
1979
The decays of the isomeric 9/2+ states which have been produced by (d, pγ) and (3He, xnγ) reactions, have been investigated in three N = 89 nuclei. The half-lives have been determined to be 5.1 ± 0.3 ns in 149Nd and 3.5 ± 0.4 μs in 153Gd. In 155Dy a 5.5 ns half-life was found, but we were unable to assign it to the 9/2+ state. The calculated E1 transition probability from the 9/2+ state has been used as a probe in suggesting the following main components for the lowest-lying 7/2- state: 7/2 5/2-[523] in 149Nd, 7/2 3/2-[521] in 153Gd and 7/2 3/2-[521] in 155Dy. The corresponding 7/2- state in 151Sm is proposed to be 7/2{1}3/2-[532] + 5/2-[523]{1}. All calculations have been performed using a…
Determination of ion-induced K-shell ionization cross sections by comparison with nuclear Coulomb excitation
1979
Abstract A new method for the determination of cross sections for K-shell ionization of heavy atoms by charged particles is proposed. The method is based on a comparison of photon lines due to K X-rays and low-energy γ-rays, the latter ones being produced in nuclear Coulomb excitation with accurately known cross sections. This procedure applies within a limited energy range to the study of targets comprising deformed even nuclei, but can also be extended to other targets having Z≳30. A test of the new technique has been carried out for Gd, W, Th and U natural targets irradiated by 4.75 MeV protons. For Th, also energies of 6.80–10.10 MeV were used. The results are briefly discussed with ref…
Etude des relations criblo-vasculaires entre les différents organes de la tige de la vigne (<em>Vitis vinifera</em> L.)
1979
<p style="text-align: justify;">Etude de la structure vasculaire reliant à la tige les feuilles, vrilles, grappes et bourgeons et analyse des relations entre ces organes.</p><p style="text-align: justify;">Sur un orthostique les organes de même nature ont au moins une relation entre eux ; vrilles et grappes sont en rapport direct avec feuilles et bourgeons ; il n'y a pas de communication entre feuilles et bourgeons.</p><p style="text-align: justify;">D'un orthostique à l'autre, feuilles, vrilles et grappes ne sont en relation que par les faisceaux latéraux foliaires. Les bourgeons des deux orthostiques sont anatomiquement indépendants.</p><p style="tex…
Dracocephalum ruyschiana L. (Silciems)
1979
Atradne: Rīgas rajona Silciemā, Allažu mežniecības 14. kvartālā, Silciema-Mežmuižas ceļa kreisajā pusē. Zilā un rozā forma. /// Riga district Silciem, 14 th quarter of the Forestry of Allazi, on the left side of the Silciem-Mezmuiza Road. Blue and pink shapes. // [Attēls no LU Muzeja kolekcijas Herbarium Latvicum (RIG II); (BOT1029_1)]
Effects of N, P, K fertilizers on Gigaspora calospora vesicular-arbuscular endomycorrhizae on Allium cepa
1979
International audience
Histophotometry: a new method for automated histological examination of solid tissue samples demonstrated on bladder cancer.
1979
The purpose of this study was to demonstrate the ability of a new method to discriminate between benign and malignant tissue. Tissue samples from three patients with bladder tumours and one patient with bladder diverticula have been examined by histophotometry. This method, based on the correlation of nuclear volume and nucleic acid contents per cell uses thick formalin fixed samples. The results are obtained by measurements averaging more than one hundred thousand cells per sample. By this histophotometric examination a clear differentiation between malignant and benign tissue could be achieved. It was also possible to determine the degree of malignancy and to differentiate between infiltr…
Endogenous role of epoxide-hydratase. Development of a steroid epoxide-hydratase assay and properties of the enzyme.
1979
A highly sensitive and rapid radiometric assay for the determination of specific epoxide hydratase activity with a steroid epoxide (16α, 17α-epoxy-1,3,5(10)-estratrien-3-ol, ‘estroxide’) has been developed. The unreacted substrate was separated from the product 1,3,5(10)-estratrien-3,16β,17α-triol by extraction into light petroleum. The product was then extracted into ethyl acetate and measured by scintillation spectrometry. Radiochromatography established that after subtraction of the blank the entire radioactivity measured in the ethyl acetate phase resulted from the product 1,3,5(10)-estratrien-3,16,17-triol, whilst high performance liquid chromatography with the four possible isomers of…
Anwendung der Glas Carbon Elektrode für die Quecksilberbestimmung in Flußwasser mittels der Differential-Puls inversen Voltammetrie (DPAW)
1979
Abstract The Glassy Carbon Electrode was used for Mercury determination in “synthetic solutions” as well as in river water by stripping Voltammetry. Best results were obtained with a supporting electrolyte of the chemical composition 0.1m KSCN, 0.025 n HCl and 20ng/mlCu2+. The optimal pH was found to be 2.8 and the optimal deposition potential-1.0 volt. It is possible to determine at to 1.5ppb Hg2+ in river watersamples. Es wurde die Glas Carbon Elektrode benutzt, urn Quecksilber sowohl in “synthetischen Losungen” als auch in Fluswasser invers-voltammetrisch zu bestimmen. Fur die Bestimmung hat sich ein Grundelektrolyt der Zusammensetzung 0.1m KSCN, 0.025 n HCl und 20ng/ml Cu2+ gut bewahrt.…
Nucleoside phosphotransferase of chick embryo
1979
This paper describes a purification procedure and some properties of a nonspecific nucleoside phosphotransferase of chick embryo, an activity which catalyzes the transfer of chick embryo, an activity which catalyzes the transfer of the phosphate ester from a deoxyribonucleotide or a pyrimidine ribonucleotide to a deoxyribonucleoside acceptor. The enzyme is very unstable to heat, dilution and dialysis and it is almost entirely inactivated by DEAE-cellulose chromatography or gel filtration. A marked enhancement in its stability is caused by numerous nucleotides. In these experiments at least 920-fold purification was obtained by using dTTP (50 microM) as nucleotide protector. The enzyme, puri…
Inhibitoren der Korrosion 25(1) - Über die Rolle der Kationen in Neutralsalzen bei der Korrosion von Eisenwerkstoffen in Gegenwart von Sauerstoff
1979
Die Geschwindigkeit des Sauerstoffverbrauchs bei der Korrosion von jeweils 500 mg DAB6-Eisenpulver wird in Abhangigkeit von der Art des Kations in Neutralsalzen (Chloriden) unter Standardbedingungen bestimmt. In Gegenwart von Alkali-, Quartaren Ammonium, Quartaren Phosphonium-und Erdalkalichloriden ist die Geschwindigkeit des Sauerstoffverbrauches vergleichbar gros. Mit Zink-, Cadmium-, Nickel-und Kobaltchloriden wird aber im Bereich von pH5 bis pH7 eine uberraschend grose Verzogerung der Sauerstoffaufnahme beobachtet. Es handelt sich mit hoher Wahrscheinlichkeit um eine Blockade der kathodischen Bezirke in der Eisengrenzflache durch Abscheidung der schwerloslichen basischen Hydroxyde von Z…
Half-lives, neutron emission probabilities and fission yields of neutron-rich rubidium isotopes in the mass regionA=96 toA=100
1979
Neutron-rich rubidium isotopes were produced by thermal-neutron induced fission of235U and were isolated by surface ionization and mass separation. The new isotope (51 ±17) ms100Rb was identified. The half-lives of the rubidium isotopes with mass numberA=96 toA=100 were measured using neutron multiscaling or gamma multispectrum analysis. Measurements of the delayed-neutron emission probabilityP n of99Rb and of the fission yields of97Rb,98Rb, and99Rb were performed.
Einige polymerspezifische Anwendungen der Schwingungsspektroskopie
1979
Anhand dreier Beispiele wird erlautert, wie man durch eine Analyse der Frequenzen, Intensitaten und Linienformen konformationsempfindlicher Banden des Schwingungsspektrums Einblick in die Struktur polymerer Festkorper erlangen und die elastischen Eigenschaften der Einzellamellen studieren kann. Im ersten Beispiel wird die Komponentenstruktur des Ramanspektrums von Polyathylen behandelt. Die Analyse ergibt, das neben orthorhombisch-kristallinen und schmelzartig-amorphen Bereichen auch ubergangsbereiche existieren mussen, in denen die Ketten zwar gestreckt, jedoch lateral ungeordnet gepackt sind. Die Anteile der drei koexistierenden Phasen lassen sich bestimmen. Die beiden anderen Beispiele b…
Fever in pregnancy and congenital anomalies.
1979
Monoamine Oxidase Inhibition by β-Carbolines: A Quantum Chemical Approach
1979
Monoamine oxidase inhibition by beta-carboline derivatives is related to the energy change, delta E, arising from complex formation between the inhibitor and the enzyme. The energy change was expressed in terms of electronic indexes, which were estimated for a set of aromatic beta-carbolines. The electronic indexes were correlated to the experimental activity indexes by a simplified quantum chemical perturbational treatment with a multiple regression procedure. A characteristic structure for the inhibitor-enzyme complex was derived from the correlation. The molecules are linked by two kinds of bond. One involves the lone pyridine nitrogen pair of beta-carbolines; the other is due to a pi-el…
AbsoluteE0 andE2 transition rates and collective states in116Sn
1979
AbsoluteE0 andE2 transition rates in116Sn have been measured using several newly developed techniques. ManyE2 transitions are observed to have a collective character withB(E2) values of up to 60 W.u. The presence of deformed excited states in116Sn is discussed in view of the results obtained.
Das System 2‐Halogenethylester/Cholinester als Zweistufen‐Schutzgruppe für die Carboxylfunktion von Aminosäuren und Peptiden
1979
Das System 2-Chlorethyl- und 2-Bromethylester/Cholinester wird als Carbonsaure-Schutzfunktion beschrieben. Die 2-Chlorethyl-(OEt(Cl))- und die 2-Bromethylester (OEt(Br)) der Aminosauren (4) lassen sich einfach herstellen und mit Z- und Boc-Aminosauren zu Z- und Boc-Dipeptidestern 5 und 6 verknupfen. Die Esterfunktionen sind gegen nicht zu stark saure und basische Einflusse bestandig. Sie konnen mit Natriumiodid in DMF in 2-Iodethylester 8 ubergefuhrt werden, welche mit Zink in einer Eintopfreaktion spaltbar sind. Durch Umsetzung mit Trimethylamin gehen die hydrophoben 2-Halogenethylester in die hydrophilen Cholinester 10 und 11 uber. Diese sind sehr stabil gegen Sauren. Sie konnen in wasrig…
Sex Differences in Feedback: Effects on Rod-and-Frame Performance
1979
It has been demonstrated that feedback is effective in changing rod-and-frame performance for women if given the opportunity to adjust the rod to the vertical repeatedly from the same starting position. It is also shown that the significant difference between males and females in the Rod-and-frame Test is carried by the large difference in the initial tilting position.