showing 36 of ~574560 from 574555 documents
Hepatic extraction of isosorbide dinitrate in cardiac patients
1983
Hepatic extraction of organic nitrates, including that of isosorbide dinitrate (ISDN), has been thought to be nearly complete in man but has never been directly measured. We examined the time course of plasma ISDN and metabolite concentrations in arterial and hepatic venous blood in four cardiac patients receiving an intravenous ISDN infusion. Apparent hepatic extraction of ISDN was high (90%) at the beginning of infusion but fell to about 44% 1 hr after termination of infusion. The decrease in ISDN concentration gradient across the liver correlates with an increase in plasma isosorbide-5-mononitrate concentration, but a cause-and-effect relationship resulting from metabolite inhibition can…
Modifications induced on the amygdaloid paroxysmal activity by entopeduncolar or nigral injection of kainic acid, in the cat.
1983
Entopeduncolar or nigral injection of kainic acid determines an early decrease of the evoked amygdaloid paroxysmal activity and a later increase of the after discharge duration. This biphasic effect is likely due to the structural analogy of the drug with monosodium glutamate, a neuroexcitant amino acid. The data suggest that the basal ganglia exert a tonic control on the amygdaloid activity.
Le temps : lieu de rencontre des économistes et des éducateurs
1983
International audience; L'article décrit les conditions dans lesquelles l'éducation est apparue au coeur des préoccupations des économistes. Il rappelle que la dimension temporelle de la scolarisation permet d'interpréter celle-ci comme un investissement à long terme. Cependant, le temps dans l'éducation a subi une double évolution: d'une part, l'allongement universel de la durée de formation, d'autre part, le découpage rigide de la vie entre le temps de formation et le temps de production.L'article avance que cette double évolution n'est pas irréversible et qu'elle n'est commandee ni par la rationalité économique ni par des exigences d'ordre pédagogique. Il suggère que les économistes et l…
A method for the territorial organization of socio-sanitary services
1983
The need for a profound change in the health service has recently led to the development of a national sanitary plan, which the Italian government has submitted to the political and social forces as a midterm strategy for the transformation of the health service.
Zur Geometrie der Translationsstrukturen mit eigentlichen Dilatationen
1983
Lactate complexes of molybdenum(VI)
1983
Spectrophotometric and cryoscopic studies of the molybdenum(VI)-lactic acid (C3O3H6) system show the existence of three different oxoanion complexes in aqueous solution which have been isolated as [Co(en)3]3+ salts. These are one molybdodilactate {[MoO2(C3O3H42]2−} and two dinuclear 1/1 species: [Mo2O5(C3O3H4)2(H2O)2]2− and [Mo2O3(OH)3-(C3O3H4)2]−. The pH of the medium is the main variable, controlling the formation equilibria which are similar to those previously described for other α-hydroxy-acid ligands.
Chromatographic and mass spectrometric characterization of the structures of the polypeptide antibiotics samarosporin and stilbellin and identity wit…
1983
The structural identity of the polypeptide antibiotics, samarosporin I(II) and stilbellin I(II) with emerimicin IV(III) has been established by thin-layer chromatography, quantitative amino acid analysis by ion-exchange chromatography, gas-liquid chromatography of the N-pentafluoropropionyl amino acid n-propyl esters and N,O-bis-pentafluoropropionyl phenylalaninol with quartz capillaries coated with the chiral stationary phase N-propionyl-L-valine-tert-butylamide, and determination of the relative molecular masses and sequence-specific fragments by field desorption fast atom bombardment mass spectrometry. The separation of closely related sequence analogues of the above polypeptides could b…
Kristallisation und schmelzverhalten von fraktionen verzweigten polyethylens, 1. Darstellung und charakterisierung der fraktionen
1983
A branched polyethylene with broad molecular weight distribution was separated into a series of fractions by fractional precipitation from dilute solution. The fractions were characterized by viscometric and density measurements, IR-spectroscopy and calorimetry. The methyl group content and the density turned out as largely constant. Molecular weight effects show up in the melting behaviour. The main range of melting and the end of the melting curve shift to lower temperatures with decreasing molecular weight. Compared to the overall extension of the melting range these shifts are small. One has to conclude that polydispersity gives only a minor contribution to the broadening of the melting…
Bourgogne, l'entrée des jeunes dans la vie active
1983
Dans quelles conditions les jeunes, sorties à différents niveaux du système éducatif, vont-ils pouvoir s'insérer dans le monde du travail, en Bourgogne ? Dans quels secteurs d'activité se retrouvent ces débutants après leur scolarité ? Par quels emplois ? Dans le système scolaire, il existe une différenciation marquée entre les filières menant aux différents baccalauréats, entre l'enseignement général et l'enseignement technique, entre les spécialités industrielles de CAP ou tertiaires de BEP, entre les classes d'enseignement général et les classes pré-professionnelles ... Cette hiérarchisation omniprésente, liée à l'orientation des élèves, influe sur les sorties des jeunes à différents niv…
[99mTc]Ca-Phytate: Some colloidal characteristics related to the optimal preparation conditions
1983
Abstract Some physico-chemical characteristics of the colloidal radiopharmaceutical [ 99 m Tc]Ca-phytate related to optimal preparation conditions have been studied. (1,2) It is demonstrated that the Ca 2+ -phytate stoichiometry is 6:1. Two different Ca-phytate colloids seem to be formed, mainly depending on the Ca 2+ :phytate molar ratio-one of low mycelar size for a 1:1 Ca 2+ :phytate molar ratio ( cmc ∗ = 5.10 −5 M ) , and another one, with a higher mycelar size for a 6:1 molar ratio (cmc = 8.10 −5 M). This last one it probably better for providing a good quality splenic uptake.
The g-factor of the J?=12+ isomeric state in188Hg
1983
Using the reaction175Lu(19F, 6n) theg-factor of the188Hg isomeric state (Jπ=12+,T1/2=135 ns) has been measured with the TDPAD method. The experimental value g=−0.168(10) supports the interpretation of an almost pure (vi13/2)−2 configuration for this isomer.
The effects of glucocorticoids on thymidine kinase and nucleoside phosphotransferase during development of chicken embryo retina.
1983
AbstractThymidine kinase in chick embryo retina reaches its highest values on the 8–10th day of development, then declines reaching the lowest value at hatching. The rate of DNA synthesis essentially follows this activity while, in contrast, nucleoside phosphotransferase increases progressively during development. Glucocorticoids at 5 × 10−6M lower the level of thymidine kinase in isolated retinas of chick embryo. The most effective steroid was hydrocortisone. The effect was observed in retinas from 8–18-day-old chick embryo and, except on the 18th day, was always of the same magnitude. We suggest that a glucocorticoid can be the natural factor responsible for the marked fall in thymidine k…
Hereditary angioneurotic oedema and blood-coagulation: interaction between C1-esterase-inhibitor and the activation factors of the proteolytic enzyme…
1983
C-1-inactivator (C-1-INA) does not only exert its important inhibitory functions in the complement system but also in the first step in the activation of the coagulation, fibrinolytic and kallikrein system. We therefore determined in nine patients with hereditary angioneurotic oedema (HANE) with obvious quantitative or functional defects of C-1-INA, and one further patient with Quincke-type oedema of different origin, the coagulation factors of the initial phase such as Hageman factor, plasma thromboplastin antecedent (PTA) and high molecular weight kininogen (HMWK). These factors were further correlated with the concentration as well as functional activity of C-1-INA. Nine of ten patients …
Synthese von Giycopeptiden: Selektive C-terminale Deblockierung und Peptidkettenverlängerung an Glucosylserin-Derivaten
1983
Benzyloxycarbonyl-(Z-)serin-2-bromethylester (3b) wird mit 2,3,4,6-Tetra-O-benzoyl-α-D-gluco-pyranosylbromid (14) zum Glucosylserinester 15 verknupft. Nach Umwandlung in den entsprechenden 2-Iodethylester 23 wird die Carboxygruppe durch Eliminierung mit Zink selektiv deblockiert. Dabei bleiben die Z- und die Kohlenhydrat-Schutzgruppen sowie die empfindliche O-glycosidische Bindung unverandert erhalten. Das Glycosyl-Z-serin 24 reagiert mit Aminosaure-2-bromethylestern 2 zu geschutzten Glycodipeptid-2-bromethylestern 18, die nach selektiver Carboxydeblockierung zu Glycotripeptidestern 25 C-terminal verlangert werden. Wahrend geschutzte Serin-Dipeptide 5 mit 14 zu Konjugaten 18 glycosyliert we…
Association of a polyuridylate-specific endoribonuclease with small nuclear ribonucleo-proteins which had been isolated by affinity chromatography us…
1983
Immunoglobulins, containing antibodies against U1-snRNP, have been prepared from a patient with systemic lupus erythematosus. After coupling these antibodies to a Sepharose matrix, U-snRNPs have been isolated and purified from rat liver nuclei by use of immunoaffinity chromatography. The resulting RNPs had the typical protein pattern of U-sn RNPs and a sedimentation coefficient of 12 S. The U-snRNP preparation was associated with an endoribonuclease which required Mg2+ for optimal activity. The enzyme, with an pH optimum of 6.2, degraded only poly(U). Other single-stranded polyribo- and polydeoxyribonucleotides, tRNA, as well as double-stranded RNA and DNA were not digested. The products of…
ChemInform Abstract: LOCATION OF TRANSITION STATES AND STABLE INTERMEDIATES BY MINIMAX/MINIMI OPTIMIZATION OF SYNCHRONOUS TRANSIT PATHWAYS
1983
The MINIMAX/MINIMI concept for the location of transition states and/or stable intermediates of chemical reactions is introduced, based on the synchronous transit method. According to this strategy, minimization of quadratic synchronous transit path maxima or minima is achieved by constrained exhaustive optimization of internal coordinates. The method and its efficiency are demonstrated for two-dimensional model surfaces as well as for thermally allowed electrocyclic interconversions of cyclopropyl-/allyl-cation and cyclobutene-/butadiene (gauche) within the framework of MNDO-SCF calculations. Thus, in both cases a direct comparison with the exact solution determined by minimization of the …
false
1983
The first dissociation constant of oligonuclear phenolic compounds consisting of one nitrophenol unit besides further alkyl phenol units (10 dinuclear, 15 trinuclear, 6 tetranuclear compounds, and 4 nitrophenols as model) was determined spectroscopically in water/methanol (50/50 by vol.) at 25°C. For the ortho-linked title compounds with the nitrophenol unit at the end of the molecule a decrease of pK1 is observed which becomes stronger with increasing chain length. The introduction of bulky groups in ortho-position of the dissociating phenolic unit, as well as at the opposite end of the molecule causes a further decrease of pK1. The lowest value is found for a p-nitrophenol unit in the mid…
Effects of endurance training on alkaline protease activities in rat skeletal muscles.
1983
This study aimed at comparing the effects of running and swimming training protocols and the termination of training on the activities of two proteases with alkaline pH-optima (alkaline protease and myofibrillar protease) in the tibialis anterior, soleus, and gastrocnemius muscles of male rats. The training on treadmill decreased the activities of alkaline and myofibrillar proteases by approx. 10-20% in the muscles studied. The activities of both proteases were unchanged in swimming-trained rats. Two weeks after the termination of running training the activity of alkaline protease was increased in gastrocnemius muscle but not in the other muscles. Swimming training increased the activity of…
Fonction de production, productivité et progrès technique à l'hôpital : une étude statistique par catégories d'établissements
1983
Notre propos et l'objet de la recherche qui le sous tend ne sont ni polémiques, ni théoriques, mais simplement statistiques, et donc se situent en deçà du débat évoqué, tout en contribuant à 1'éclairer. Quel est le rôle de la main-d1 oeuvre dans la production hospitalière ? Quelle est l'incidence de la spécialisation du travail sur l'évolution de la main-d'oeuvre ? Quel est l'impact conjugé du progrès technique et de l'humanisation des conditions de soins et d'hébergement sur la combinaison des facteurs de production à l'hôpital ? Y-a-t-il complémentarité ou substitution entre la main-d'oeuvre et le capital technique ? Peut-on apprécier l'existence de rendements d'échelle ? La réponse à ces…
Uptake of [3H]dopamine into dopaminergic and noradrenergic neurones of the isolated neurointermediate lobe of the rat hypophysis. Effects of desipram…
1983
The isolated neurointermediate lobe (NIL) of the rat hypophysis accumulates [3H]dopamine from the incubation medium. Column chromatographic analysis showed that 92% of the tissue radioactivity was contained in the catecholamine fraction. [3H]Dopamine represented 70% and [3H]noradrenaline 30% of the [3H]catecholamines. Desipramine (1 microM) prevented the formation of [3H]noradrenaline without affecting the storage of [3H]dopamine. Nomifensine (10 microM) blocked the storage of [3H]dopamine and [3H]noradrenaline. Thus, in the NIL, [3H]dopamine is taken up into dopaminergic and noradrenergic neurones. In the latter, [3H]dopamine is converted to [3H]noradrenaline, indicating a significant dopa…
Evidence of chloroethylene oxide being the reactive metabolite of vinyl chloride towards DNA: comparative studies with 2,2′ -dichloro-diethylether
1983
The roles of chloroethylene oxide (CEO) and chloroacetaldehyde (CAA) in carcinogenicity of vinyl chloride (VC) have been studied by comparing biological effects of VC exposure with those of 2,2'-dichlorodiethylether (bis(chloroethyl)ether, BCEE) as a metabolic precursor of CAA. Biological end-points investigated were covalent protein binding, nucleic acid (RNA and DNA) alkylation and the potency of the two chemicals to induce preneoplastic ATPase-deficient foci in rat liver. After exposure of rats to [1-14C]BCEE, BCEE derived radioactivity was bound to liver proteins. Analysis of hydrolysates of liver RNA and DNA gave no indication for the formation of either 7-N-(2-oxoethyl)guanine, 1,N6-e…
On generalized covering subgroups and a characterisation of ?pronormal?
1983
Introduction. The context of this note is the theory of Schunck classes and formations of finite soluble groups. In a 1972 manuscript Fischer [4] generalized the concept of an ~-covering subgroup of a group G to a (P, ~)-covering subgroup, where P is some pronormal subgroup of G, and proved universal existence (for P satisfying a stronger embedding property) in case the class ~ is a saturated formation. The fact tha t the Schunck classes are the classes ~ with the property that every group has an ~-projector [9, 4.3, 4.4; 6] (which coincides with an ~-covering subgroup in the soluble universe | [6, II.15]) raises the question whether it is possible to determine the whole range of universal …
The resistivity and thermopower of amorphous Mg-Zn alloys
1983
The resistivity and thermopower of amorphous Mg-Zn alloys have been computed as a function of temperature and composition. The diffraction model incorporating the dynamical partial structure factors is applied. The effect of the electron mean free path is investigated. The authors find that the resistivity is well described by the model, and that the inclusion of the mean free path does not change the results considerably. In the case of thermopower the diffraction model turns out to be inadequate: it gives a composition dependence which is against the experimental evidence. This suggests that there exists another scattering mechanism, which is not accounted for by the diffraction model. Th…
16α-Iodo-3,17β-estradiol: A stable ligand for estrogen receptor determinations in tissues with high 17β-hydroxysteroid dehydrogenase activity
1983
Recently, the successful synthesis of radioiodinated 16 alpha-iodo-3,17 beta-estradiol-[125I] [125I]E2 was reported [1]. This new ligand has similar binding characteristics to the estrogen receptor (ER) [2-5] as the currently used tritium labeled estradiol [3H]E2. However, it offers several advantageous features: (a) high specific activity (theoretically 2,000 Ci/mmol) [1]; (b) minor problems with radioactive waste due to its short half life and (c) the possibility of simultaneous determination of ER and progesterone receptors (PgR) by double labeling with [125I]E2 and [3H]R5020 [6, 7]. As we are presently trying to determine ER and PgR in human placental cytosols we were interested in the …
Stability of the radiopharmaceutical []DMSA: Study of the ligand exchange reaction with [99Tc]EDTA
1983
Abstract A kinetic study was made of the ligand exchange reaction between [ 99 m Tc]EDTA and DMSA. The results of this study indicate that this exchange reaction is closely related to temperature and pH. Kinetic and thermodynamic parameters demonstrate that both complexes—[ 99 m Tc]EDTA and [ 99 m Tc]DMSA—have a similar stability. Furthermore, the existence of an acid-basic catalysis for the global exchange reaction was established, and the catalytic parameters were calculated. These data were obtained by radiochromatography and visible spectrophotometry.
Radioactively labelled epoxides. Part IV. Tritium labelled α- and β-methyl styrene oxides
1983
Tritium labelled α-methyl styrene oxide (2-methyl-2-phenyloxirane) and cis- and trans-β-methyl styrene oxides (Z- and E-2-methyl-3-phenyl oxirane) have been prepared using tritiated water as the inexpensive source of tritium. The two geometrical isomers of β-methyl styrene oxide were synthesized by a sequence of reactions which led to stereochemically pure products, and obviated any need to separate the isomers.
A study of the polymorphism and ethnic distribution differences of human serum paraoxonase
1983
The enzyme serum paraoxonase shows a polymorphism in Europeans which is governed by two alleles. The first allele has a gene frequency plow of 0.716–0.777, and is manifested as a low activity group in homozygotes. More than 50% of all European test subjects can be included in this group. A second allele with a gene frequency qhigh of 0.223–0.284 was found in typical European distributions and is manifested in both the form of a second heterozygotic and a third homozygotic group with high activities. The Hardy-Weinberg rule for a two-allele model is valid for the distribution. The gene frequency plow of the first allele decreases as one moves from Europe in the direction of Africa and Asia. …
Cooperative studies of chemoprophylaxis after transurethral resection of bladder tumors
1983
Large cooperative trials are more likely than series studied by small groups to bring about significant progress in the field of intravesical adjuvant chemotherapy of superficial bladder tumor. Multicenter randomized trials involving large numbers of patients have been conducted in Europe by the EORTC Urological Group. The Group's main objectives were to compare the efficacy of thio-TEPA, VM-26, epodyl, Adriamycin, and cisplatin, against no treatment, and to study the prophylactic effect of oral pyridoxine and evaluate the main prognostic factors. The results obtained so far are reported. Preliminary information is also given about the Blinst study, a multicenter open investigation of local…
false
1983
The neutron scattering from mixtures of deuterated and undeuterated poly(ethylene oxide), (D-PEO, H-PEO), in the small angle and intermediate angle region has been measured in the melt. We found no indications of a molecular segregation. The value of molecular weight evaluated agreed with that obtained by other methods. For a sample with a molar mass of 120000 g/mol the radius of gyration 〈rw2〉1/2 was found to be 13,6 nm, which corresponds to a characteristic ratio of C = 6,9. The form factor of a single chain can be described by the Debye equation for a random coil with the same unperturbed dimensions. Our results are compared with rotational isomeric state calculations and measurements in…
Isocortical Pathology in Type C Niemann-Pick Disease
1983
A case of Niemann-Pick disease was examined with Golgi preparations and a transparent Golgi impregnation counterstained for intraneuronal pigment deposits. There was a specific type of storage of unmetabolized substrate restricted to certain nerve cell types. The most conspicuous changes in the isocortex were: 1) dilated axonal segments in layer IIIab pyramidal cells filled with storage material; the volume of these axonal expansions often exceeded that of the soma; 2) distension of layer IIIc, layer V, and layer VIa pyramidal cell perikarya with storage material; 3) new formation, elongation, and vertical orientation of basal dendrites in layer V pyramidal cells; 4) well-preserved pyramida…
Antibakterielle Konzentrationen in Serum und Geweben aus dem Zahn-Kieferbereich nach perioperativer Einnahme von Propicillin
1983
Nach der operativen Entfernung radikularer und follikularer Zysten im Kieferbereich wurden bei 40 Patienten Serum, Knochen, Zystenbalg und Zystenflussigkeit auf ihren Gehalt an Propicillin untersucht. Die Patienten hatten ein oder zwei Stunden vor der Entnahme der Untersuchungsmaterialien 1 Mega E (0,7 g) Propicillin als Oblongtablette oral erhalten. Ein bzw. zwei Stunden nach der Einnahme des Propicillin betrugen die Verteilungskoeffizienten zwischen Serum und den drei Geweben 0,78 bzw. 0,87 fur die Spongiosa, 0,07 bzw. 0,06 fur den Zystenbalg und 0,14 bzw. 0,08 fur die Zystenflussigkeit. Die mittleren Konzentrationen in allen drei Geweben lagen mindestens zwei Stunden lang deutlich uber d…
The effect of two low doses of aspirin on whole blood thromboxane and prostacyclin generation in healthy subjects
1983
SummaryThe effects of two low doses of aspirin (20 mg and 100 mg) on prostacyclin and thromboxane formation during whole blood clotting were studied in 8 healthy volunteers.A single 100 mg aspirin dose caused more than 90% reduction of both serum TXB2 and 6-keto-PGF1α; a single 20 mg dose of aspirin inhibited serum TXB2 more than 6-keto-PGF1α but effects on these two products could not be completely dissociated.However, the effect of a single 20 mg aspirin dose on serum TXB2, was of much longer duration than its inhibitory effect on PGI2 synthesis during whole blood clotting.
Comment les jeunes enfants communiquent entre eux
1983
International audience
Increased prolyl 4-hydroxylase activity in the myocardium of endurance-trained mice.
1983
Endurance training over 3, 10 or 20 days increased the activity of prolyl 4-hydroxylase (PH) in the left ventricle of mice. No increase was observed in the weight of the left ventricle, in galactosylhydroxylysyl glucosyltransferase activity or in hydroxyproline concentration. The increase in PH suggests that the synthesis of collagen increases during physiological adaptation of the heart to endurance exercise without changes in the ventricle weight or its total collagen content.
Allylester als selektiv abspaltbare Carboxyschutzgruppen in der Peptid- undN-Glycopeptidsynthese
1983
Allylester eignen sich als Schutz der Carboxyfunktion bei Peptid- und N-Glycopeptidsynthesen und konnen von Aminosauren einfach hergestellt werden. Unter den Bedingungen der Boc- und Z-Gruppenabspaltung im Sauren sind die Allylester bestandig. Durch Behandlung mit katalytischen Mengen von Tris(triphenylphosphan)rhodium(I)-chlorid in Ethanol/wasser (9:1) werden sie im neutralen bis schwach basischen Milieu schonend gespalten. Der N-terminale Schutz und die N-glycosidische Bindung bleiben dabei unverandert erhalten. Die dadurch mogliche selektive Deblockierung der α-Carboxyfunktion geschutzter N-glycosylierter Asparagin-Derivate 15 wird zur gezielten C-terminalen Kettenverlangerung zu N-Glyco…
Funciones de produccion en los centros de ensenanza superior Franceses
1983
International audience