952 resultados para Vias biliares – Obstruções
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At a time of changes on the territory during the 19th century, the political and socioeconomic elites of the province and later State of Rio Grande do Norte evolved a discourse in order to justify the permanence of Natal as a city holding a status of capital. In this work we analyze the means employed by the ruling classes to impose their wish to raise Natal to an outstanding position among the existing cities by intervening on the territory during a period of one hundred years (1820-1920). During that time, which was characterized by changing commercial flows and technological development, the elites interventions were essentially directed to the implementation of modes of transportation, especially the railway. We try to understand the reinforcement of Natal as a capital city not only in political and administrative terms, but mainly in a commercial and symbolic manner, through the discourse and interventions undertaken by the local administrative elites, who stimulated the creation of a set of relations on the territory that also imprinted visible marks in the capital s urban fabric. These interventions were based upon the establishment of an infrastructure for exporting the State s production, firstly through and despite the Potengi River, and later on by the construction of railways. Although the project of Natal s hegemony had been outlined before the establishment of the railway network, in both cases the ultimate objective was to reinforce and develop the capital city as a commercial urban center to the detriment of other cities
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Os atuais esquemas de modulação e acesso ao meio, tais como o Wide- Band Code-Division Multiple Access (WCDMA) ou Orthogonal Frequency- Division Multiple Access (OFDMA), que são otimizados para a gestão eficiente do espetro electromagnético e elevada taxa de transmissão, originam sinais de elevado Peak-to-Average Power Ratio (PAPR) e requisitos de linearidade rigorosos. As arquiteturas de amplificação tradicionais, i.e. baseadas no operação em modo de corrente do dispositivo ativo, são incapazes de satisfazer estes requisitos em simultâneo. Assim, o amplificador de potência (do inglês, Power Ampli_er (PA)) incorre numa degradação significativa de rendimento energético em favor de maior linearidade, aumentando simultaneamente os custos de operação das estacões base para os operadores de telecomunicações móveis e o impacte ambiental. Este trabalho foca-se no estudo da arquitetura Doherty, a principal solução encontrada para melhorar o compromisso linearidade/rendimento para aplicações em estações-base de comunicações móveis. Para tal, são expostos os princípios básicos de amplificadores de rádio frequência assim como a análise teórica do tradicional PA Doherty (do inglês, Doherty Power Amplifier (DhPA)) de duas vias e suas variantes. O estudo _e complementado com o projeto e implementação de um PA excitador, em classe-AB, e de um DhPA de elevada potência, colocando-se em prática a teoria e técnicas de projeto estudadas ao longo deste trabalho, aliadas aos desafios da implementação com dispositivos reais de elevada potência.
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Con el objetivo de valorar la patología biliar y sus variedades en 100 pacientes de ambos sexos y cualquier edad ingresados al hospital regional Vicente Corral Moscoso de Cuenca y que fueron sometidos a intervención quirúrgica año 1992. Determinar el o los métodos auxiliares de diagnóstico utilizados para confirmar el diagnóstico clínico. Establecer el manejo clínico y terapeútico preoperatorio utilizados.
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Con un diseño cuasiexperimental se realizó un estudio clínico en el hopital Vicente Corral de Cuenca que incluyó 80 pacientes de ambos sexos asignados a dos grupos: 1.- grupo COLELAP formado por cuarenta pacientes a los que se realizó colecistectomía laparoscópica y 2.- grupo CONVENC formado por 40 pacientes a los que se realizó colecistectomía abierta. El procedimiento fue similar para ambos grupos. En los dos grupos se midieron a.- los niveles de cortisol prequirúrgico y posquirúrgico mediante radioinmunoanálisis [Coat-A cortisol r], b.- El dolor antes y después de la cirugía mediante una escala visual y c.- La estadía hospitalaria y las complicaciones. No hubieron diferencias estadísticamente significativas en cuanto a edad, género, procedencia, nivel de instrucción, dolor preoperatro y valoraciones sanguíneas de laboratorio. Los valores de cortisol del grupo COLELAP fueron inferiores a los del grupo CONVENC tanto en el preoperatorio 9.40 más menos 4.81 vs. 20.11 más menos 8.87 [p = 0.001] como en el postoperatorio 12.19 más menos 4.12 vs. 22.1 más menos 7.31 [p=0.0001], sin embargo en el grupo COLELAP el aumento promedio [2.8 mcg/dL vs 1.99 mcg/dL fue mayor. El dolor preoperatorio evaluado mediante una escala análoga visual fue igual en ambos grupos [p=0.22] pero en el postoperatorio fue menor en el grupo COLELAP [p=0.012]. El tiempo quirúrgico promedio fue mayor para el grupo CONVENC [82.25 más menos 31.66 min vs 63.5 más menos 31.23 min] [p=0.0005]. El 90 por ciento de los pacientes del grupo fue de 3.1 más menos días y para el grupo CONVENC de 4.8 más menos 0.87 días. La diferencia fue altamente significativa [p=0.00001]. En conclusión laparoscópica muestra significativas ventajas frente a la colecistectomía abierta; a.- Minimiza el trauma quirúrgico, b.- produce menor dolor postoperatorio y c.- disminuye la estadía hospitalaria
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Lipids can modulate the risk of developing sporadic colorectal adenocarcinoma (SCA), since alterations into lipid metabolism and transport pathways influence directly cholesterol and lipids absorption by colonic cells and indirectly reactive oxygen species (ROS) synthesis in rectum cells due to lipid accumulation. Lipid metabolism is regulated by several proteins APOA1, APOB, APOC3, APOE, CETP, NPY, PON1 and PPARG that could influence both metabolism and transport processes. Is been reported that several common single-nucleotide polymorphisms (SNPs) in these genes could influence their function and/or expression, changing lipid metabolism balance. Thus, genetic changes in those genes can influence SCA development, once the majority of them were never studied in this disease. Furthermore, there are contradictory results between some studied polymorphisms and SCA risk. Thus, the aim of this study was to explore and describe lipid metabolism-associated genes common polymorphisms (APOA1 -75 G>A; APOB R3500Q; APOC3 C3175G, APOC3 T3206G; APOE Cys112/158Arg; CETP G279A, CETP R451Q; NPY Leu7Pro; PON1 Q192R; PPARG Pro12Ala) status among SCA, and their relationship with SCA risk. Genotyping of common lipid metabolism genes polymorphisms (APOA1 75 G>A; APOB R3500Q; APOC3 C3175G, APOC3 T3206G; APOE Cys112/158Arg; CETP G279A, CETP R451Q; NPY Leu7Pro; PON1 Q192R; PPARG Pro12Ala) were done by PCR-SSP techniques, from formalin-fixed and paraffin-embedded biopsies of 100 healthy individuals and 68 SCA subjects. Mutant genotypes of APOA1 -75AA (32% vs 12%; p=0.001; OR=3.51; 95% CI 1.59-7.72); APOB 3500AA (7% vs 0%; p=0.01); APOC3 3175GG (19% vs 2%; p=0.0002; OR=11.58; 95% CI 2.52-53.22), APOC3 3206GG (19% vs 0%; p<0.0001); CETP 279AA (12% vs 1%; p=0.003; OR=13.20; 95% CI 1.61-108.17), CETP 451AA (16% vs 0%; p<0.0001); NPY 7CC (15% vs 0%; p<0.0001); PPARG 12GG (10% vs 0%; p=0.001); and heterozygote genotype PON1 192AG (56% vs 22%; p<0.0001; OR=4.49; 95% CI 2.298.80) were found associated with SCA prevalence. While, APOE E4/E4 (0% vs 8%; p=0.02) mutant haplotype seemed to have a protective effect on SCA. Moreover, it also been founded differences between APOB 3500GA, APOC3 3206TG, CETP 279AA genotypes and PPARG 12Ala allele prevalence and tissue localization (colon vs rectum). These findings suggest a positive association between most of common lipid metabolism genes polymorphisms studied and SCA prevalence. Dysregulation of APOA1, APOB, APOC3, CETP, NPY, PON1 and PPARG genes could be associated with lower cholesterol plasma levels and increase ROS among colon and rectum mucosa. Furthermore, these results also support the hypothesis that CRC is related with intestinal lipid absorption decrease and secondary bile acids production increase. Moreover, the polymorphisms studied may play an important role as biomarkers to SCA susceptibility.
Resumo:
Lipids can modulate the risk of developing sporadic colorectal adenocarcinoma (SCA), since alterations into lipid metabolism and transport pathways influence directly cholesterol and lipids absorption by colonic cells and indirectly reactive oxygen species (ROS) synthesis in rectum cells due to lipid accumulation. Lipid metabolism is regulated by several proteins APOA1, APOB, APOC3, APOE, CETP, NPY, PON1 and PPARG that could influence both metabolism and transport processes. Is been reported that several common single-nucleotide polymorphisms (SNPs) in these genes could influence their function and/or expression, changing lipid metabolism balance. Thus, genetic changes in those genes can influence SCA development, once the majority of them were never studied in this disease. Furthermore, there are contradictory results between some studied polymorphisms and SCA risk. Thus, the aim of this study was to explore and describe lipid metabolism-associated genes common polymorphisms (APOA1 -75 G>A; APOB R3500Q; APOC3 C3175G, APOC3 T3206G; APOE Cys112/158Arg; CETP G279A, CETP R451Q; NPY Leu7Pro; PON1 Q192R; PPARG Pro12Ala) status among SCA, and their relationship with SCA risk. Genotyping of common lipid metabolism genes polymorphisms (APOA1 75 G>A; APOB R3500Q; APOC3 C3175G, APOC3 T3206G; APOE Cys112/158Arg; CETP G279A, CETP R451Q; NPY Leu7Pro; PON1 Q192R; PPARG Pro12Ala) were done by PCR-SSP techniques, from formalin-fixed and paraffin-embedded biopsies of 100 healthy individuals and 68 SCA subjects. Mutant genotypes of APOA1 -75AA (32% vs 12%; p=0.001; OR=3.51; 95% CI 1.59-7.72); APOB 3500AA (7% vs 0%; p=0.01); APOC3 3175GG (19% vs 2%; p=0.0002; OR=11.58; 95% CI 2.52-53.22), APOC3 3206GG (19% vs 0%; p<0.0001); CETP 279AA (12% vs 1%; p=0.003; OR=13.20; 95% CI 1.61-108.17), CETP 451AA (16% vs 0%; p<0.0001); NPY 7CC (15% vs 0%; p<0.0001); PPARG 12GG (10% vs 0%; p=0.001); and heterozygote genotype PON1 192AG (56% vs 22%; p<0.0001; OR=4.49; 95% CI 2.298.80) were found associated with SCA prevalence. While, APOE E4/E4 (0% vs 8%; p=0.02) mutant haplotype seemed to have a protective effect on SCA. Moreover, it also been founded differences between APOB 3500GA, APOC3 3206TG, CETP 279AA genotypes and PPARG 12Ala allele prevalence and tissue localization (colon vs rectum). These findings suggest a positive association between most of common lipid metabolism genes polymorphisms studied and SCA prevalence. Dysregulation of APOA1, APOB, APOC3, CETP, NPY, PON1 and PPARG genes could be associated with lower cholesterol plasma levels and increase ROS among colon and rectum mucosa. Furthermore, these results also support the hypothesis that CRC is related with intestinal lipid absorption decrease and secondary bile acids production increase. Moreover, the polymorphisms studied may play an important role as biomarkers to SCA susceptibility.
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Las células gigante tipo osteoclásticas (CGTO) del páncreas son una entidad poco frecuente descrito originalmente por Rosaien 1968, caracterizado por osteoclastos, que son células gigantes mononucleares idénticas a las células del estroma observadas en tumores óseos. Desde entonces, hay pocos informes de los tumores que contienen células gigantes en otras localizaciones anatómicas. Las CGTO se pueden distinguir de las células gigantes tipo pleomórficas (CGTP), debido a la falta de un marcado pleomorfismo nuclear asociado. A menudo, un carcinoma de páncreas histológicamente reconocibles acompaña CGTO, dando lugar a un mal resultado. Formas puras de CGTO presentan un mejor pronóstico porque se necesita mucho tiempo para desarrollar metástasis, pero esta forma es muy raros, con pocos casos reportados en la literatura Inglésa. La mayoría de veces se discute el diagnóstico de benignidad de estos tumores basados en la evaluación de inmunohistoquímica. El presente caso se trata de una paciente de sexo femenino de 56 años de edad con cuadro caracterizado por dolor tipo cólico que mejora con antiespasmódicos, de varios meses de evolución, con periodos de remisión y exacerbación. A examen físico presenta: en piel y mucosas ligero tinte subictérico, a nivel abdominal: abdomen doloroso de forma difusa sin viseromegalias o masas palpables
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Doutoramento em Economia.
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A doença de Alzheimer constitui uma ameaça significativa a nível mundial. Estima-se que, mundialmente existam cerca de 35 milhões de pessoas afetadas por este tipo de demência. Os compostos contendo um esqueleto benzocicloalcanol (que incluem benzofuranos e di-hidrobenzofuranóis) mostram atividades biológicas significativas e possuem muito potencial no tratamento das doenças neurodegenerativas. Nos últimos anos têm havido avanços significativos no campo das reações catalisadas por metais. As reações de adição nucleófila intramolecular e a de Heck intramolecular constituem metodologias importantes para a síntese de benzocicloalcanóis. No âmbito deste trabalho, pretendia-se sintetizar uma biblioteca de compostos contendo um esqueleto benzocicloalcanol. A estratégia adotada para a síntese de dihidrobenzofuranóis envolveu um método de ciclização catalítica de cetonas aril-éteres e para a síntese de benzofuranos, um método de ciclização catalítico de enoatos e enamidas (amidas de Weinreb). Várias condições foram estudadas; Abstract: Studies on Synthetic Catalytic Pathways to Benzocycloalkanols and Derivatives – Potential Drugs for Alzheimer’s Disease Alzheimer's disease constitutes a significant threat worldwide. It is estimated that are about 35 million people worldwide suffering from this type of dementia. The compounds containing a benzocycloalkanol scaffold (including benzofurans and dihydrobenzofurans) show significant biological activity and have great potential in the treatment of neurodegenerative diseases. In recent years there have been many advances in the field of catalyzed reactions by transition-metals. The intramolecular nucleophilic addition and the intramolecular Heck reactions constitute important methods for the synthesis of benzocycloalkanols. Within this work, the main goal was to synthesize a library of compounds containing a benzocycloalkanol scaffold. The adopted strategy for the synthesis of dihydrobenzofurans was the catalytic cyclization of aryl ether ketones and for the synthesis of benzofurans, the catalytic cyclization of enoates and enamides (Weinreb amides). Several conditions were studied
Resumo:
At a time of changes on the territory during the 19th century, the political and socioeconomic elites of the province and later State of Rio Grande do Norte evolved a discourse in order to justify the permanence of Natal as a city holding a status of capital. In this work we analyze the means employed by the ruling classes to impose their wish to raise Natal to an outstanding position among the existing cities by intervening on the territory during a period of one hundred years (1820-1920). During that time, which was characterized by changing commercial flows and technological development, the elites interventions were essentially directed to the implementation of modes of transportation, especially the railway. We try to understand the reinforcement of Natal as a capital city not only in political and administrative terms, but mainly in a commercial and symbolic manner, through the discourse and interventions undertaken by the local administrative elites, who stimulated the creation of a set of relations on the territory that also imprinted visible marks in the capital s urban fabric. These interventions were based upon the establishment of an infrastructure for exporting the State s production, firstly through and despite the Potengi River, and later on by the construction of railways. Although the project of Natal s hegemony had been outlined before the establishment of the railway network, in both cases the ultimate objective was to reinforce and develop the capital city as a commercial urban center to the detriment of other cities
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Malgré l'augmentation constante de l'efficacité des cellules photovoltaïques multi-jonctions destinées au photovoltaïque concentré, des pertes de performances subsistent à haute concentration solaire. Elles sont principalement causées par un ombrage excessif dû aux métallisations ou par effet Joule à cause de la résistance série. Une des solutions à ce problème est de reporter le contact métallique en face avant sur la face arrière grâce à des vias métallisés et isolés électriquement. Avec cette architecture, les pertes dues à l'effet Joule et à l'ombrage seront limitées et des gains en efficacité sont attendus. Toutefois, l'intégration de vias sur des cellules photovoltaïques triple jonction favorise la recombinaison électron-trou en surface et peut provoquer une perte de performances de ces dispositifs. Ce mémoire présente les travaux de recherche effectués visant à étudier précisément cette problématique ainsi qu'à proposer des solutions pour limiter ces pertes. L'objectif est d'évaluer les pertes de performances de cellules photovoltaïques triple jonction suite à l'intégration de vias. Dans un second temps, l'objectif secondaire vise à limiter les pertes grâce à des traitements de passivation. Les résultats et solutions qu'apporte ce projet représentent une étape clé dans la réalisation de cette nouvelle architecture de contact électrique pour cellules photovoltaïques. En effet, les conclusions de ce projet de recherche permettent de valider la possibilité d'obtenir des gains en efficacité grâce à cette architecture. De plus, les procédés de microfabrication présentés dans ce projet de recherche proposent des solutions afin d'intégrer des vias sur ces hétérostructures tout en limitant les pertes en performances.
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Neste trabalho avaliam-se e comparam-se metodologias tradicionais de prospeção e construção de captações de água subterrânea em países em vias de desenvolvimento, neste caso do Sul da Ásia (Butão, Bangladeche, Índia, Nepal e Paquistão). Faz-se uma análise às metodologias do ponto de vista geológico (diversos tipos de aquífero, litologias, graus de fracturação e alteração), mecânico (técnica das metodologias de perfuração e construção das captações), e económico (comparação dos tempos de avanço das sondagens, dos tempos de construção das captações, da produtividade das mesmas e seus custos). Conclui-se que as metodologias de prospeção low cost e tradicionais são semelhantes em âmbito e em cenário de aplicação, e que, ainda que as segundas sejam mais caras, têm custos muito menores em comparação com as convencionais. Conclui-se ainda que as metodologias convencionais de construção de captações estão pensadas para metodologias convencionais de prospeção, e que as low cost são muito semelhantes entre si; Abstract: The present work evaluates and compares traditional methods of borehole drilling and construction for water abstraction in developing countries, particularly South Asia (Bhutan, Bangladesh, India, Nepal and Pakistan). The methods are analyzed in regards to geology (types of aquifers, lithologies, massif fractures and weathering), mechanic (borehole drilling and abstraction technologies), and economic (comparing the progression in drilling and construction of boreholes, productivity and its costs) factors. It is concluded that the traditional drilling methods are similar in scope and application set, and that, though the latter are more expensive, they cost less than conventional methods. It is also concluded that conventional borehole construction is based in conventional drilling methods, and that the diverse low cost methodologies are very similar between them.