showing 36 of ~574560 from 574555 documents
A comparison of the effects of bilateral efferent duct ligation and of partial epididymectomy on the testes of rats.
1990
Testis weight as a percentage of body weight did not change following bilateral ligation of the efferent ducts (EDL) close to the epididymis, whereas following removal of part of the epididymis between the site of ligation and a point close to the junction between the caput and corpus (PCE), testis weight first rose linearly until Day 4 and then showed an exponential decrease between Days 4 and 28. After EDL, the perimeter of the seminiferous tubules rose for the first 7 days and then remained elevated, whereas after PCE, there was a linear decrease between Days 4 and 28. Following EDL, the percentage of altered and degenerated tubular cross-sections rose to about 30% and 10%, respectively,…
Mechanism of inhibition of hepatic monoxygenases
1990
International audience
First observation of beta-delayed deuteron emission
1990
5 pages, 2 figures.
Diagnosis of perioperative myocardial necrosis following coronary artery surgery — a reappraisal of isoenzyme analysis
1990
Although the routine determination of CK-MB activity is widely used after coronary artery bypass grafting (CABG), the diagnosis of a perioperative myocardial necrosis remains arbitrary. The intention of the present study was to develop discriminative enzymatic parameters of CK-MB activity in a collective of 710 patients following CABG. Patients were grouped according to their postoperative electrocardiogram (ECG). For each patient, the time activity curve of CK-MB was determined. The total amount of CK-MB was calculated by integrating the area beneath the CK-MB activity curve. Patients presenting with an unchanged postoperative ECG (group I) or a new bundle branch block with uncompromised h…
Estabilización de modelos económicos dinámicos con control óptimo en tiempo continuo
1990
En esta Tesis de Licenciatura se lleva a cabo el estudio de un problema determinado de optimización dinámica y sus aplicaciones en el campo de la Ciencia Económica. Un problema de optimización consiste, fundamentalmente, en la búsqueda de un extremo de una función o un funcional objetivo que proporcione un máximo o un mínimo para esa función. Cuando se habla de optimización dinámica hay que incorporar el factor tiempo al problema, en todas y cada una de las diferentes variables que intervienen, lo que afectará a los modelos matemáticos que se empleen para representar el comportamiento y las relaciones existentes entre dichas variables. También afecta al funcional objetivo a optimizar. Así, …
Male malum metuo, Espressioni di paura nella palliata
1990
Dopo la problematica inerente alla presenza dominante in un contesto comico del sentimento della paura, che di solito ha sede privilegiata nella dimensione tragica, ho cercato di delineare un quadro, quanto più possibile completo, di questo ingrediente del comico plautino e terenziano, procedendo su quattro binari livellari che comprendono un referente funzionale, basato sulla frase minima "A teme B", un referente linguistico basato su quegli scarti linguistici di cui la fabula palliata è paradigmatica, unreferente extralinguistico (gesto, movimento), in cui consiste il fenomeno teatrale, un referente sociale che consiste nel rapporto emittente-destinatario. In questa direzione ho esaminato…
Estructura socioprofesional de los rurales castellonenses
1990
El estudio pretende poner de relieve la difícil situación sociodemográfica en que se encuentran los municipios rurales de la provincia de Castelló, como consecuencia del intenso éxodo que han sufrido desde principios del siglo XX. En muchos pueblos, pensionistas y jubilados superan a la población económicamente activa. Entre los activos la mayor parte se ocupa en el sector agrario; sólo en las localidades más próximas al litoral se da una cierta diversificación profesional. Buena parte de los rurales debe desplazarse diariamente desde el municipio de residencia al de trabajo. La ocupación en actividades agrarias, o no agrarias, en el mismo municipio de residencia o en localidades más o men…
Lecciones sobre la filosofía de la historia universal. Introducción general
1990
El document forma part dels documents docents programats per la Universitat de València amb la col.laboració de la Generalitat Valenciana El libro consta de dos partes. La primera parte consiste en la versión completa del texto de Hegel que figura como "Introducción general" a sus Lecciones sobre la filosofía de la historia universal (trad. de José Gaos). La segunda parte consiste en un conjunto informaciones y actividades, sobre el texto de Hegel, elaboradas por Julián Marrades como material didáctico para la enseñanza de la Filosofía en el bachillerato.
Programme de recherche sur le mont Beuvray, rapport annuel 1990
1990
Ce rapport rend compte des travaux effectués au cours de l'année 1990 dans le cadre du programme de recherche sur le mont Beuvray sous la direction scientifique de Bibracte (Jean-Paul Guillaumet, coordonnateur scientifique).
New Neutron-Rich Nuclei and Isomers Produced in Symmetric Fisson
1990
The novel method for rapid on-line mass separation, the IGISOL, is described. The method has been shown applicable to mass separation of short-lived proton-induced fission products without any chemical dependence on radionuclide. Recent results on isomeric states with half-lives of the order of milliseconds produced directly in proton-induced fission of 238U and separated with the IGISOL are presented. The future plans for connection of the new K-130 cyclotron of the University of Jyvaskyla with the IGISOL are reviewed.
Growth Kinetics of Wetting Layers at Surfaces
1990
Monte Carlo simulation of lattice gas models for the wetting transitions in systems with short range forces are described. A nearest-neighbor simple cubic lattice with nonconserved “Glauber dynamics” is used, applying a slab geometry (LxL cross section). It is shown that the growth proceeds in two stages: for short times t, the thickness of the wetting layer at an initially nonwet wall increases proportional to the logarithm of the time; for t » L2(lnL)2 the thickness increases proportional to t1/2/L. Generalizations to other systems are briefly discussed. Also two-dimensional growth of a wetting film at surface steps is considered, considering “terraces” of an LxM geometry with M»L as subs…
Lead, cadmium and chromium content of edible vegetables grown in three different agricultural areas
1990
(1990). Lead, cadmium and chromium content of edible vegetables grown in three different agricultural areas. Food Additives & Contaminants: Vol. 7, No. sup1, pp. S22-S25.
Chemical analysis of the sex pheromone glands of Thaumetopoca bonjeani (Powel) (Lep. Thaumetopoeidae)
1990
International audience
La nueva concepción del relieve peninsular a finales del siglo XIX y comienzos del XX
1990
La articulación de diversas unidades morfoestructurales para definir el relieve peninsular es un tema que interesó hondamente a los geógrafos y geólogos del siglo XIX y comienzos del XX y sería después base esencial de las llamadas ¿regiones naturales¿. La relectura de unas páginas de Lapparent, a veces olvidado, nos ha sugerido estas notas sobre algunas de esas cuestiones.
Los hostaleros del burdel de valencia
1990
Organic chlorine compounds in lake sediments. IV. Dioxins, furans and related chloroaromatic compounds
1990
Abstract Polychlorodibenzo-p-dioxins (PCDDs), polychlorodibenzofurans (PCDFs), polychloronaphthalenes (PCNs) and coplanar PCBs were measured in surface sediments from 18 lake areas in Central Finland. Toxic 2, 3, 7, 8-substituted PCDD and PCDF congeners occurred at low levels (
Role of S-adenosyl-L-methionine in the treatment of intrahepatic cholestasis.
1990
Recent studies have established the clinical efficacy of S-adenosyl-L-methionine (SAMe) in the treatment of cholestasis associated with hepatic diseases, pregnancy and the administration of estrogen-containing oral contraceptives. In 4 clinical trials involving a total of 639 patients with cholestasis due to acute or chronic liver disease, SAMe in an intravenous dose of 800 mg/day or an oral regimen of 1.6 g/day for 2 weeks was superior to placebo in relieving the symptom of pruritus and in restoring serum total bilirubin and serum alkaline phosphatase towards normal. The drug is also effective in intrahepatic cholestasis of pregnancy (ICP), with intravenous administration of 800 mg/day for…
Estudio histológico de la respuesta reparativa, en patología experimental, en menisco implantado en músculo estriado y en fondo de saco subcuadricipi…
1990
El menisco implantado en músculo estriado y en fondo de saco subcuadricipital se regenera formándose tejido conectivo fibroso en las áreas de defecto tisular, tejido que es mucho más abundante cuando se implanta en fondo de saco subcuadricipital, lo mismo que la neoangiogénesis previa. En ninguno de los casos se aprecia transformación cartilaginosa. Los resultados obtenidos parecen apoyar la hipótesis de que es necesaria la existencia de conexión vascular entre las áreas a reparar y el territorio del que parten los vasos neoformados y las células fibroblásticas relacionadas con éstos. The meniscus ingraft in striated muscle and in articular cavity of the knee, was regenerated growing fibrou…
Likelihood Calculations in Paternity Testing on the Basis of DNA-Fingerprints
1990
DNA-fingerprints seem to be a powerful tool in paternity testing. But the quantification of the results in terms of likelihood and likelihood ratios is a problem, because in most cases the correct genetic model and its parameters are not known. Two approaches have been suggested to circumvent these problems. The use of band sharing rates to distinguish between pairs of relatives and pairs of unrelated individuals, and the calculation of likelihood ratios on the basis of simplifying assumptions. The first approach reduces the available genetic evidence to “phenotypic” similarities. The second one makes unjustified simplifying assumptions. These two decision strategies have to be examined wit…
Analytic curves in power series rings
1990
Salmonella-reactive Synovial Fluid T-cell Clones in a Patient with Post-infectious Salmonella Arthritis
1990
From a patient with reactive arthritis following Salmonella typhimurium enteritis, synovial fluid T-lymphocytes were cloned and expanded in vitro. Seven out of 74 clones showed a marked proliferative response to antigens of heat-killed Salmonella typhimurium with autologous T-cell-depleted peripheral blood mononuclear cells as antigen-presenting cells. The Salmonella-reactive clones were of the CD4+ phenotype, antigen-induced proliferation could be inhibited by a monoclonal antibody to HLA class II. One clone recognized both Salmonella and Campylobacter jejuni antigens in the proliferation assay. The multiclonality of Salmonella-reactive synovial fluid T-cells indicates that the microorgani…
Problems in the management of chronic hepatitis B with interferon: experience in a randomized, multicentre study.
1990
In a multicentre trial, 82 patients known to be hepatitis B e antigen and hepatitis B virus DNA positive for at least 1 year, with elevated serum alanine aminotransferase levels and chronic liver lesions on biopsy, were randomized to receive either recombinant interferon alfa-2a at a dose of 4.5 million units thrice weekly for 4 months or no treatment. At the end of therapy, viral DNA clearance and aminotransferase normalization were significantly (p less than 0.05) more frequent in treated patients than in controls. After 16 months' follow up, the difference was still significant for hepatitis B e antigen clearance and transaminase normalization. Hepatitis B virus DNA reactivation was obse…
Tunica vaginalis Free Grafts for Closure of Urethrocutaneous Fistulas
1990
In 32 patients a tunica vaginalis free graft was used for closure of urethrocutaneous fistulas (n = 26) or complicated hypospadias repair (n = 6). All patients had at least one operation (average 3.9) for urethral reconstruction prior to this procedure. 12 patients had recurrent fistulas (average 2.2). The technique proved to be very successful. Only 2 patients had to undergo subsequent reoperation for recurrent fistulas. The use of a free tunica vaginalis graft interposed between skin and urethra is our method of choice in the repair of recurrent or complicated urethrocutaneous fistulas.
Antimetastatic activity of adriamycin in combinations with proteinase inhibitors in mice
1990
The antimetastatic activity of adriamycin in combination with proteinase inhibitors was investigated in mice bearing the metastatic tumors L1210 leukemia, Lewis lung carcinoma or M5076 sarcoma. Leupeptin, a cathepsin B inhibitor, when administered as a single agent was devoid of antimetastatic activity but some therapeutic activity was noted in mice with Lewis lung carcinoma when the agent was administered in combination with adriamysin. Pepstatin A, a cathepsin D inhibitor, had no effect as a single agent in mice with L1210 leukemia but displayed some antimetastatic activity in mice with Lewis lung carcinoma. In mice with M5076 sarcoma the combination of pepstatin A and adriamycin resulted…
La campagne franco-hongroise de fouilles de 1988 à Velem-Szentvid
1990
International audience
Problemas en torno al inicio de la Romanización en Mallorca
1990
Clusters-a New Source for Atomically Engineered Materials
1990
ABSTRACTThe electronic structure and properties of small clusters are strongly dependent on their size. These size specific properties are illustrated by confining the discussion to three different topics (1) interaction of hydrogen with clusters (2) effect of temperature and magnetic field on the magnetization of clusters and (3) reaction of clusters with gas atoms. It is shown that the electronic energy levels that are strongly dependent on cluster size give rise to the size specific electronic properties of clusters. In cluster hydrides certain elements are found to absorb more hydrogen per atom in cluster form than in a crystalline form. The magnetization of clusters increases as a func…
First Electrophilic Substitutions of 3-Substituted Indoles with Diethoxycarbenium Tetrafluoroborate: Functionalized Indole Derivatives
1990
The indoles 2a-2c react with diethoxycarbenium tetrafluoroborate (1) to furnish the indolecarbaldehydes 3a-3d. In the thermodynamically controlled reaction of 3-methylindole (2a) with 1 the tris(indolyl)methane 4 and diskatole (5), are formed in addition. The limitations of these reactions are discussed and evidence is presented for a C-3-ipso-attack and a Wagner-Meerwein rearrangement, respectively, leading to the formation of 3b or 3d. Erste elektrophile Substitution von 3-substituierten Indolen mit Diethoxycarbenium-Tetrafluoroborat: Funktionalisierte Indol-Derivate Die Indole 2a-2c reagieren mit dem per se synthetisierten Diethoxycarbenium-Tetrafluoroborat (1) zu den Indolcarbaldehyden …
El concepto de "Doctrina de la ciencia" en el escrito "Über den begriff der wissenchaftslehre" de Fichte
1990
1. El objetivo de este artículo es exponer la noción fichteana de filosofía a la luz del escrito programático sobre el concepto de Doctrina de la Ciencia, 1974. Obra meramente introductoria a la filosofía como Doctrina de la Ciencia, no contiene aún desarrollos doctrinales cumplidos, limitándose a realizar un examen puramente lógico y de validez meramente hipotética o problemática del concepto de Doctrina de la Ciencia, examen previo a su realización efectiva de un sistema filosófico y de la que dependerá la validez de ese examen preliminar.
Estudio de los elementos ornamentales de la Cova de Papalló
1990
Nuestra Experiencia con la técnica de Barcat y Godart en el Torticolis Muscular Congénito
1990
Los autores exponen los resultados obtenidos en diez casos de T.M.C. tratados quirúrgicamente con la técnica de Barcat y Godard, tanto estéticos como funcionales. Se analizan los parámetros de sexo, edad de intervención, lado afectado, tipo de parto, anomalías asociadas, y presencia de asimetría facial, movilidad craneal, pérdida de relieve muscular y aparición de bandas laterales postoperatorias. Estos resultados son comparados con los otros autores, mostrándose superiores. The author s expos e the results obtained in ten case s of congenital muscular torticolis treated surgicaly with Barcat and Godar's procedure, as much aesthetic as functional results. They analyze the parameters: sex ag…
Administration of Second-Generation Extracorporeal Shock Waves without Waterbath for Fragmentation of Extra- and Intrahepatic Bile Duct Stones
1990
First-generation extracorporeal shock-wave sources disintegrate 97% of kidney stones [1, 2]. Recently, in selected patients gallbladder and common bile duct stones were also treated. The technique available so far, however, requires immersion of the patient’s body in a tank of degassed water. The procedure is therefore inconvenient, time consuming, and relatively expensive. The high pressure of shocks (up to 1000 bar) generated by underwater spark discharge causes pain, and general anesthesia is necessary in most patients [3, 4].
Nuclear Ground-State Properties from Laser and Mass Spectroscopy
1990
Atomic physics played an important role in establishing our present-day knowledge on the atomic nucleus. Especially mass spectrometry and optical spectroscopy were the main sources of information on nuclear properties in the early days of nuclear physics. Still now, precise information on nuclear masses (or binding energies) are obtained by mass spectrometry whereas mass differences between two isotopes are usually determined by nuclear-spectroscopy techniques via a determination of the Q-value of nuclear reactions or decay. Almost all our information on the nuclear spins I, the nuclear magnetic dipole moment μ I, the spectroscopic quadrupole moment Q, and the changes in the mean-square cha…
Perioperatives Risiko bei Whipple-Operation und biliodigestiver Anastomose beim Pankreaskarzinom
1990
Die Frage nach der Art des chirurgischen Vorgehens beim Pankreaskarzinom ist Gegenstand kontroverser Diskussionen, obwohl gerade in den letzten Jahren die Morbiditat und Mortalitat der partiellen Duodenopankreatektomie deutlich gesenkt werden konnten [1, 3, 7, 8, 12, 13]. Andererseits wurden verschiedene nichtoperative Verfahren als Alternative zur biliodigestiven Anastomose entwik- kelt. Das eigene therapeutische Konzept umfast bei lokalisiertem Tumorwachstum die partielle oder Duodenopankreatektomie, und bei lokaler oder allgemeiner Inoperabilitat sowie bei Tumorgeneralisierung die biliodigestive Anastomose zur Gallenableitung.
Metabolism of 3-hydroxychrysene by rat liver microsomal preparations
1990
3-Hydroxychrysene, a metabolite of the polycyclic aromatic hydrocarbon (PAH) chrysene, was metabolised by rat liver microsomal preparations obtained from Arochlor 1254-pretreated rats. Eight major metabolites were isolated by high performance liquid chromatography and characterised by u.v. spectroscopy and a variety of mass spectrometric techniques. The metabolites were unambiguously identified as 9-hydroxy-trans-1,2-dihydroxy-1,2-dihydrochrysene and 9-hydroxy-r-1,t-2,t-3,c-4-tetrahydroxy-1,2,3,4-tetrahydrochrysene and tentatively identified as 3-hydroxy-trans-5,6-dihydroxy-5,6-dihydrochrysene (since chrysene is a symmetrical molecule the 3- and 9-positions are equivalent), 9-hydroxy-trans-…