showing 36 of ~574560 from 574555 documents
Supplément bibliographique à l'ouvrage de G. Lefebvre
1989
Supplément bibliographique à l'ouvrage de G. Lefebvre
Antimicrobial activity of selected plants employed in the Spanish mediterranean area. Part II
1989
The antimicrobial properties of 59 plants used in folk medicine to treat general infectious diseases were studied. The in vitro antimicrobial activity of chloroform and methanol plant extracts were assayed using the agar-streak method and 38 of them showed activity against some of the microorganisms tested. Bioautography established the probable active compounds. Inhibition bands were identified as containing terpenoids and polyphenolic compounds.
Changing the size of a cavity via an electron-transfer: synthesis and reduction of 1,5,22,26-tetraoxa-[5,5]-(2,8)-dibenzo[a,e]cylooctatetraenophane
1989
Abstract The synthesis and electron transfer reactions of the title compound, the first macrocycle incorporating two cyclooctatetraene units, are described.
Une méthode rapide et simple pour l'estimation de la position de la courbe de dissociation de l'oxyhémoglobine
1989
The methods currently available for assessing the oxyhaemoglobin dissociation curve parameters are expensive, lengthy, require a large volume of blood, and the results obtained are modified by anaesthetic gases. The equipment required for the method described includes: a microtonometre, microcuvettes, 3 gas bottles containing different oxygen, carbon dioxide and nitrogen mixtures (4.5%, 5.6%, 89.9%; 3.5%, 5.6%, 90.9%; 2.5%, 5.6%, 91.9% respectively), a microxymetre, and a micropHmetre. The samples in the microcuvettes are incubated at 37 degrees C in a gas flow of 45 ml.min-1 from the bottles. SO2 is then read using the microxymetre. P50, i.e. PO2 at 50% saturation, is calculated, as well a…
Epistemologia empirista sense dogmes
1989
Josep Lluís Blasco critica en aquest article la concepció fonamentista del coneixement, d’arrel cartesiana i basada, sobretot, en el dogma empirista que afirma que els enunciats, als que classifica segons la dicotomia analític-sintètic, poden tenir confirmació o refutació aïlladament, en suposar un atomisme semàntic que defensa que tot enunciat amb significat és reductible a un enunciat sobre la experiència immediata. Per tal de realitzar la seua crítica, que té com a blanc principal l’empirisme tradicional, el Wittgenstein del Tractatus i el positivisme lògic, Blasco es basa en Quine, Tarsky i el segon Wittgenstein i defensa un holisme semàntic, ontològic i epistemològic. Segons el holisme…
Estudio DS 103-282: Relajante Muscular en Lumbalgia Aguda o Lumbago : (estudio doble ciego de Tizanidina + Paracetamol V s Placebo + Paracetamol)
1989
The clinic efficiency and tolerance of tizanidina + paracetamol was compared with placebo+ paracetamol in an estadistical study and in with were treated 50 patients diagnosed of acote back pain or lumbago. Dif'ferent clinical parámeters was dimished in the group ofthe group of tizanidina + paracetamol.
Carbanionic Polymerization: Kinetics and Thermodynamics
1989
For a kinetic analysis, the process of anionic polymerization has to be divided into at least three main reactions common to all types of polymerization (equations 1–3). I* denotes initiator, M monomer, Pi* and Pi′ an active or inactive polymer chain of degree of polymerization i, respectively, and X a terminating agent.
Aryl radicals by copper(II) oxidation of hydrazines: A new method for the oxidative and reductive arylation of alkenes
1989
Abstract A new source of aryl radicals interesting from the preparative point of view has been found in the reaction of arylhydrazines and copper(II) sulfate. The process allows selectively both the reductive and oxidative arylation of alkenes.
Occurence of geometrical isomers of eicosapentaenoic and docosahexaenoic acids in liver lipids of rats fed heated linseed oil
1989
Mono trans geometrical isomers of 20:5 n-3 and 22:6 n-3 were detected in liver lipids of rats fed heated linseed oil. The isomers were identified as being 20:5 h5c,8c,11c,14c,17t and 22:6 h4c,7c,10c,13c,16c,19t. These fatty acids were isolated as methyl esters by preparative high-performance liquid chromatography IHPLC) on reversed phase columns followed by silver nitrate thin layer chromatography (AgNO3-TLC). The structures were identified using partial hydrazine reduction, AgNO3-TLC of the resulting monoenes, oxidative ozonolysis of each monoene band, and gas-liquid chromatography (GLC) of the resulting dimethyl esters and monomethyl esters. Fourier-transform-infrared spectrometry confirm…
CT and MR Imaging of Non-neoplastic Intracranial Masses
1989
Many intracranial mass lesions of non-neoplastic origin present CT and MR features similar or identical to those of true neoplasms. In many cases a definitive diagnosis cannot be made from imaging findings alone, and misinterpretation is possible even when the history and clinical findings are considered. Yet an accurate preoperative diagnosis is an essential prerequisite for selecting candidates for a neurosurgical operation and planning the procedure. In some cases the full range of neuroradiologic techniques may have to be applied and evaluated in the context of clinical findings before the physician can accurately classify the disease and draw appropriate therapeutic conclusions.
Muscarinic modulation of acetylcholine release: Receptor subtypes and possible mechanisms
1989
The release of acetylcholine from central and peripheral neurones can be inhibited and facilitated by muscarine autoreceptors, i.e. receptors located on the cholinergic neurone. In the last few years evidence has accumulated that muscarine receptors are heterogeneous. This chapter describes attempts that have been made to classify the muscarine autoreceptors. In addition, some possible mechanisms behind the neuronal muscarine receptors are examined.
Исследования древних карт республик Прибалтики
1989
В статьях сборника охарактеризованы коллекции древних карт университетов, архивов и музеев Прибалтийских республик, а также Государственного архива Швеции. Намечены основные проблемы научных исследований по древним картам.
El didactismo clásico de Hitchcock y la crisis de Hollywood
1989
Los films de Alfred Hitchcock abren una problemática que es a la historia a quien interesan y, sólo por esto, sus investigaciones representan la avanzadilla del cine americano durante casi dos décadas. Más tarde, cuando se produzca la revolución tecnológica de comienzos de los sesenta, cuando las escrituras europeas consigan dejar su impronta en el cine mundial, cuando los experimentos underground comiencen a reclamar un pequeño espacio, entonces la representatividad de ' Hitchcock para la historia del cine deberá ceder su lugar. Sus trabajos a partir de aquel momento serán -que nos perdone el hitchcockiano impenitente- irrelevantes para la historia. Sus obras a partir de 1963 podrán ser al…
Epinephrine and Norepinephrine Pattern in Elderly Patients with Borderline and Established Hypertension
1989
To evaluate the activity of sympathetic system and of plasm renin in elderly patients with borderline (BH) and established essential hypertension (EH), 31 BH mean age 38 years and 30 EH, mean age 39 years; 15 BH, mean age 66 years, and 15 EH, mean age 68 years, were studied at rest and after dynamic exercise. At the same time blood pressure and heart rate were automatically recorded, while blood samples were collected for PRA and plasma epinephrine (E) and norepinephrine (NE) assays. Plasma E levels showed no significant differences between the groups examined at rest. Nevertheless, young BH had higher plasma E levels than young EH after stress and elderly BH showed plasma E levels higher t…
The effects of dexametasone on the synthesis of protein, DNA, RNA, and hyaluronic acid in human synovial cells in culture
1989
Unidades de análisis para los datos de conversación
1989
Presentación de un modelo de análisis para los datos conversacionales, comparando elementos de la escuela de análisis del discurso de Birminghan (Sinclair, Coulthard) y las propuestas del análisis conversacional (Sacks, Schegloff, Jefferson).
Towards laser cooling of fast Be+ ions in the storage ring TSR
1989
Publisher Summary This chapter presents a clear understanding of laser-ion interactions under storage ring conditions to prepare the basis of laser cooling of fast-stored ion beams. In addition, the method of laser-induced fluorescence provides precise data for beam properties such as absolute velocity, momentum spread, and lifetime. 9Be+ ions stored in a heavy-ion storage ring are a promising species for laser cooling down to temperatures several orders of magnitude less than those reached for protons by electron cooling at the Novosibirsk ring. Short cooling times and microkelvin temperatures can be envisaged, where the structure of the ion beam is dominated by Coulomb repulsion. The chap…
Immunotherapy of Metastasizing Renal Cell Carcinoma
1989
119 patients with stage-IV renal cell carcinoma were treated using immunotherapy with autologous tumor vaccine. The immunization was carried out at monthly intervals, the patients were restaged every
New Schemes for the Production and Spectroscopy of Positronium
1989
The rate of positronium formation has been increased by 2–3 orders of magnitude using recently developed accelerator based slow positron sources. This opens the possibility of improvements of precision experiments on the Ps atom as well as new experiments on excited states. First evidence for enhanced metastable Ps formation is presented and future possibilities are discussed.
El diablo y su sombra
1989
Ensayo sobre la representación y la alusión al diablo en la literatura, especialmente fantástica, poniendo el énfasis en cuestiones de la retórica de la preterición.
Truncation, Information, and the Coefficient of Variation
1989
The Fisher information in a random sample from the truncated version of a distribution that belongs to an exponential family is compared with the Fisher information in a random sample from the un- truncated distribution. Conditions under which there is more information in the selection sample are given. Examples involving the normal and gamma distributions with various selection sets, and the zero-truncated binomial, Poisson, and negative binomial distributions are discussed. A property pertaining to the coefficient of variation of certain discrete distributions on the non-negative integers is introduced and shown to be satisfied by all binomial, Poisson, and negative binomial distributions.
Influence of proprioceptive information on space orientation on the ground and in orbital weightlessness
1989
Conscious space orientation depends on afferent information from different sense organs including the labyrinth, the eyes, tactile cues from the skin, joint receptors, muscle spindles, tendon organs and possibly viscera. An important role is played by impulses from the cervical position receptors in interaction with concomitant information from the otolith system. In order to isolate the effect of cervical position receptors from that of the otolith system, space experiments in orbital weightlessness and in parabolic aircraft flight were performed. It was found that stimulation of the neck receptors in weightlessness markedly influences the perception of the subjective vertical and horizont…
Diversidade da Oferta e Estratégias do Vestibulandos : o caso de Fortaleza
1989
International audience
Recent mathematical approaches to reconstruct phylogenies: A chemosystematist's and botanist's view
1989
Some basic problems of mathematical phylogenetics are discussed. While algorithms regularly depend on the principle of parsimony, some features of phylogenesis interfere with that principle. Nonrandomness of the distribution of mutations as well as the inconstancy of the molecular clock in time and within a given sequence can bias the calculated relationships of closely related taxa. True comparability of sequences is difficult to establish, since this requires defining of homology of positions and of functions of amino acids as well. Parallelism and convergence can give rise to errors in establishing homology. Furthermore, they are difficult to be integrated into a consistent mathematical …
Flebografía intraósea en el estudio de un Osteocondroma inveterado y ulcerado del pie
1989
Octylglucoside reconstitution of plasma membrane H+ -translocating ATPase from corn roots
1989
International audience
Characterization of Anti Liver Kidney Microsomal Antibody Associated with Chronic HDV Infection by Immunoblotting
1989
Cytoplasmic antibodies directed against antigen(s) present in the membranes of the endoplasmic reticulum have been reported in a proportion of patients with chronic HBV-HDV infection (Crivelli et al.,1981). While the immunofluorescence (IFL) pattern associated with LKMδ antibody is quite similar to that of the liver kidney microsomal antibody (LKM) described by Rizzetto et al. (1973) and associated with an autoimmune type of chronic active hepatitis (Thomas, 1980), the target antigen(s) was supposed to be different on the basis of blocking experiments. The target antigen of LKM antibody has been recently partially identified as a 50kD protein located in the membranes of the smooth endoplasm…
Profesors Marģers Stepermanis: biobibliogrāfiskais rādītājs
1989
Saturs: Priekšvārds. Vēstures zinātņu doktors profesors Marģers Stepermanis. /A. Rolova, I. Leinasare / Profesora vēstures zinātņu doktora M. Stepermaņa publicētie darbi. (1924.-1978.) Profesora M. Stepermaņa rediģētie darbi. Papildinājumi. Profesora M. Stepermaņa tulkotie darbi. Profesora M. Stepermaņa vadītās un oponētās disertācijas. Raksti par profesoru M. Stepermani. Bibliogrāfiskie rādītāji, kuros ievietotas profesora M. Stepermaņa publikācijas. Vēstures zinātņu doktora profesora M. Stepermaņa darbu alfabētiskais rādītājs. Personu rādītājs.
Induced changes of chlorotoluron metabolism in wheat cell suspension cultures
1989
International audience
Analyse coût-efficacité en éducation
1989
International audience
Ultrastructural Studies on Development in Mature Seeds; Embryos ofEuonymus europaeaL. Dormant or Cultured at +25 °C
1989
Ultrastructural observations on naturally dispersed and dehydrated seeds of Euonymus europaea L. were performed. It was shown that during the culture of isolated embryos at 25 °C for 7 d the maturation of protein bodies continued; the initial juvenile form (single protein body per cell with dispersed contents) was developing into a more advanced form (single body split to form several sub-units with condensed contents). Parallel biochemical determinations pointed to an increase in insoluble protein levels. There were no changes in other storage organelles, lipid bodies, either in the fine structure or in the level of triacylglycerols. Deterioration of cellular membranes (in mitochondria, pr…
Peripheral Neuropathy in the Hypereosinophilic Syndrome: A Case Report
1989
We observed a patient with the hypereosinophilic syndrome that showed as a prominent clinical feature peripheral nerve dysfunction. The neuropathy evolved over 4 months and affected sensory and motor functions. Nerve conduction studies and EMG were compatible with axonal neuropathy. Nerve and muscle biopsies revealed severe axonal degeneration with neurogenic atrophy of muscle. Morphometry of peroneal nerve showed marked axonal loss, more prominent in large myelinated fibers. There was no evidence of vasculitis process. Neuropathy is produced by eosinophil-released substances exerting a neurotoxic effect through direct altered vascular endothelial permeability and local mast cell histamine …
Las desigualdades de renta en la sociedad andaluza
1989
International audience
Psychologie et idéologie : histoire d'une interférence
1989
Trajectoires ontogénétiques et hétérochronies complexeschez des ammonites (Harpoceratinae) du Jurassique inférieur (Domérien)
1989
Evolutive transformations of ontogeny in the two main groups of Harpoceratinae which colonize the North-West Europe during the lower Domerian — Protogrammoceras (Matteiceras) and Protogrammoceras (Fieldingiceras) — are analyzed. Within P. (Matteiceras) these transformations belong to a strict heterochronical logic (translation of a standard ontogenetic trajectory). Within P. (Fieldingiceras) the alterations of the ontogeny cannot be placed in a same logic. Moreover, the P. (Matteiceras) heterochronical issues are complex: paedomorphic (neoteny) and peramorphic (acceleration) tendencies appear on both sides of critical point (inversion point) for a same feature, the ribs density.