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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Mitomicina C tópica no tratamento conservador das estenoses laringotraqueais revisão sistemática e metanálise proporcional /

Queiroga, Thereza Lemos de Oliveira January 2017 (has links)
Orientador: Daniele Cristina Cataneo / Resumo: Introdução: a mitomicina C (MMC) é um antibiótico natural utilizado inicialmente como um agente anti neoplásico. Nas vias aéreas sua aplicação promove a inibição da proliferação de fibroblastos em áreas cicatriciais. Objetivo: avaliar a efetividade e segurança da MMC tópica no tratamento conservador das estenoses laringotraqueais. Método: revisão sistemática de estudos experimentais ou observacionais que tenham avaliado as intervenções conservadoras no tratamento das estenoses laringotraqueais com o uso da MMC tópica. Foram pesquisadas as bases de dados LILACS, Pubmed, Embase, Cochrane e Web of Science. Os desfechos avaliados foram: resolução completa ou parcial, caracterizada por tempo livre de sintomas maior ou igual um ano; número de procedimentos necessários com ou sem aplicações de MMC (um ou mais); e complicações decorrentes do procedimento. Resultados: foram selecionados 14 estudos, um prospectivo randomizado, um caso-controle e doze series de casos, envolvendo 365 pacientes. Em 10 estudos a intervenção sempre contou com a utilização de MMC e em quatro foram analisados dois grupos um com MMC, e outro sem. Com o uso da MMC a resolução avaliada em 11 estudos, foi de 69% (IC a 95% 61% a 77%, I2= 22,5%). Sem MMC a resolução avaliada em somente três estudos, foi de 43% (IC a 95% 17% a 70%, I2= 59,3%). Foi realizado um único procedimento em 55% dos pacientes (IC 95% 44 a 66%, I2= 52,3%), e em 45% dos pacientes foi realizado mais de um procedimento (IC 95% 34 a 56%, I2= 52,3%... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre
92

Estudo de propriedades físico-químicas de resinas odontológicas: grau de conversão, dureza e expansão térmica

Rocha, Renata Sanches Ferreira [UNESP] 10 July 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:25:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-07-10Bitstream added on 2014-06-13T20:53:37Z : No. of bitstreams: 1 rocha_rsf_me_ilha.pdf: 3590200 bytes, checksum: f6889570ef205e6b46a549584c70a872 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / As resinas compostas vêm sendo estudadas de longa data, sempre na procura de propiciar aos clínicos um melhor entendimento do seu processo de polimerização e a obtenção de melhores resultados nos procedimentos restauradores. A proposta deste trabalho foi determinar o grau de conversão, a microdureza e o coeficiente de expansão térmica das resinas restauradoras TPH Spectrum (Dentsply) e Filtek P60 (3M), em função da profundidade. Os materiais foram polimerizados por uma fonte de luz halógena durante 40 segundos em anéis de alumínio em diferentes espessuras (1, 2, 3 e 4 mm). O grau de conversão foi determinado através da espectroscopia no infravermelho próximo com transformada de Fourier, utilizando a razão entre bandas de absorção correspondentes às ligações duplas alifáticas e aromáticas. Para tanto, foram confeccionadas pastilhas contendo 20mg de resina e 150mg de KBr e os espectros foram obtidos em um espectrômetro Nexus 670 (Nicolet). As medidas de microdureza Vickers foram obtidas com um aparelho HMV 2000 (Shimadzu), utilizando uma amostra de cada espessura. A expansão térmica foi estudada através da técnica da extensometria. Os resultados mostraram que para as duas resinas ocorre uma diminuição no grau de conversão e na microdureza à medida que se aumenta a profundidade, como esperado. Para as medidas de expansão térmica, a resina Filtek P60 não apresentou diferenças significativas nas quatro profundidades, enquanto para a resina TPH Spectrum houve um aumento no coeficiente de expansão térmica com a profundidade. Não foi observada uma correlação entre o grau de conversão e a microdureza nas duas resinas estudadas. A determinação do grau de conversão através de espectros de absorção no infravermelho próximo mostrou-se mais preciso do que quando determinado a partir de espectros na região infravermelho médio. / The composite resins have been widely studied allowing a better understanding of the process of polymerization. As consequence, better results in the clinical procedures have been obtained. The purpose of this work was to study the degree of conversion, the hardness and the thermal expansion of the TPH Spectrum (Dentsply) and Filtek P60 (3M) resins in different depths. Samples were prepared for each resin using aluminum rings 10 mm in internal diameter and with different thickness (1, 2, 3, and 4 mm). Resin composites were cured with a halogen light curing unit for 40 s. The degree of conversion was determined from FTIR spectra by comparison of the aliphatic =CH2 bond at 4743 cm -1 with that of the aromatic component at 4623 cm -1 for the cured and uncured states. For that, pellets containing 20 mg of resin powder (cured or uncured) and 150 mg of KBr powder were made. The near infra-red spectra were obtained in a FT-IR spectrophotometer (model Nexus 670, Nicolet). The Vickers hardness was measured with a Micro Hardness Tester (model HMV 2000, Shimadzu). The thermal expansion was studied through the strain gauge technique. The results showed a decrease in the value of DC and hardness as increases the depth. For Filtek P60 resin, it was not observed significant difference in the coefficient of thermal expansion at different depths. On the other hand, an increase was observed in the coefficient as it increases the depth for the TPH Spectrum resin. There is not correlation between the conversion degree and the microhardness for the two studied resins. DC values more accurate were obtained from near infra-red spectra when compared with those obtained from medium infra-red spectra.
93

Dilatações vasculares intrapulmonares e síndrome hepatopulmonar na esquistossomose mansônica

Lima, Frederico Santana de 13 August 2012 (has links)
This study aimed at determining the prevalence of the hepatopulmonary syndrome (HPS) and intrapulmonary vascular dilation (IPVD), and how they relate to the arterial oxygenation, in schistosomotic patients with the hepatosplenic form (HSE). Method: Patients with HSE were submitted to arterial gasometry and contrast transthoracic echocardiogram (CTTE). Patients with IPVD were submitted to spirometry. The criteria to identify HSE patients were positive parasitological examination of feces and/or positive epidemiology and abdominal echography compatible with the hepatosplenic form of schistosomiasis, according to the Niamey criteria WHO. Patients with other liver diseases were excluded. Criterion for HPS: PaO2 < 80mmHg and/or AaPO2 ≥ 15 mmHg, IPVD diagnosed through CTEE, in adittion to schistosomotic portal hypertension. For the data analysis, the patients were classified under three groups: Group 1 Patients with HPS; Group 2 Patients with IPVD but no alterations in arterial oxygenation; Group 3 Patients without IPVD. Results: Seventeen out of forty patients (42.5%) presented IPVD, but only six met the criteria for HPS, showing a prevalence of 15%. Among those, only one HPS patient presented a level of PaO2 lower than 80 mmHg. The average age of the 40 schistosomotic patients was 48.6 years. No nail clubbing, spider nevi, or platypnea were observed. There was no relation between gender and presence of HPS or IPVD. PaO2 and AaPO2 medians differed significantly among the groups (P = 0.001 and P = 0.005, respectively). PaO2 was significantly higher in the group with IPVD while comparing to the group with no IPVD (P = 0.001). There was no significant difference while comparing the HPS group to the group with no IPVD (P = 0.957). AaPO2 was significantly lower in the group with IPVD while comparing to the group with no IPVD (P = 0.005). There was no significant difference while comparing the HPS group to the group with no IPVD (P = 0.381). Conclusion: The results indicate that the IPVD and PHS frequency in schistosomotic patients is similar to the one found in cirrhotic patients. The presence of IPVD does not correlate with alterations of the arterial oxygenation in patients with the hepatosplenic form of schistosomiasis. It is possible that changes in gas exchange are caused by other reasons unrelated to the presence of IPVD. / O objetivo deste estudo foi determinar a prevalência da síndrome hepatopulmonar (SHP) e dilatações vasculares intrapulmonares (DVIP) e suas relações com a oxigenação arterial em pacientes esquistossomóticos da forma hepatoesplênica (EHE). Métodos: Pacientes com EHE foram submetidos à gasometria arterial e ecocardiografia transtorácica com contraste (ETC). Espirometria foi realizada nos pacientes com DVIP. Os critérios para identificação dos pacientes com EHE foram parasitológico de fezes positivo e/ou epidemiologia positiva associada à ultrassonografia de abdome superior compatível com EHE, segundo critérios de Niamey OMS. Foram excluídos pacientes com outras doenças hepáticas. Critérios de SHP: PaO2 < 80mmHg e/ou AaPO2 ≥ 15 mm Hg, DVIP diagnosticado pelo ETC, além de hipertensão portal esquistossomótica. Para análise dos dados, os pacientes foram divididos em três grupos: Grupo 1 Pacientes com SHP; Grupo 2 Pacientes com DVIP sem alterações da oxigenação arterial; Grupo 3: Pacientes sem DVIP. Resultados: Dezessete/40 pacientes (42,5%) apresentaram DVIP, mas apenas 06 cumpriram critérios para SHP, demonstrando uma prevalência de 15%. Destes, apenas 01 paciente com SHP apresentou nível de PaO2 inferior a 80 mm Hg. A média da idade dos 40 pacientes com esquistossomose foi de 48,6 anos. Os pacientes não diferiram quanto aos critérios clínicos e bioquímicos. As médias da PaO2 e da AaPO2 diferiram significativamente entre os grupos (P= 0,001 e P = 0,005 respectivamente), sendo a PaO2 significativamente maior no grupo 2 quando comparado ao grupo 1 (p = 0.022) e ao grupo 3 (P = 0,001). Não houve diferença significativa na comparação entre grupo 01 x grupo 3 (P = 0,957). O AaPO2 foi significativamente menor para o grupo 2 quando comparado ao grupo 1 (p=0.01) e ao grupo 3 (P = 0,005). Não houve diferença significativa na comparação entre grupo 01 x grupo 3 (P = 0,381). Conclusão: Os resultados indicam que, em pacientes com EHE, ocorre DVIP e SHP em frequências semelhantes às encontradas em pacientes com cirrose. A presença de DVIP parece não levar a alterações da oxigenação arterial em pacientes com esquistossomose da forma hepatoesplênica, podendo as alterações de trocas gasosas serem causadas por outros motivos não relacionados à presença de DVIP
94

La procédure de Ross : propriétés biomécaniques de l'artère pulmonaire en fonction du phénotype valvulaire aortique

Dionne, Pierre Olivier 09 1900 (has links)
La procédure de Ross: Propriétés biomécaniques de l'artère pulmonaire en fonction du phénotype valvulaire aortique Pierre Olivier Dionne, Evan Wener, Alexander Emmott, Raymond Cartier, Rosaire Mongrain, Richard Leask et Ismail El-Hamamsy OBJECTIFS: Le but de cette étude est de déterminer si les propriétés des artères pulmonaires des patients bénéficiant d'une procédure de Ross ayant une valve aortique bicuspide sont différentes que celles des patients ayant une valve aortique tricuspide. MÉTHODOLOGIE: Trente-deux artères pulmonaires et 20 aortes ont été prélevées chez des patients subissant une procédure de Ross au moment de la chirurgie, dans une cohorte de 32 patients. L'analyse histologique et l'étude tensile equi-biaxiale ex-vivo complétées dans les 8 heures suivant le prélèvement furent utilisées afin d'évaluer les différences entre les groupes de patients et entre les artères pulmonaires et les aortes ascendantes. RÉSULTATS: Il n'y avait aucune différence d'épaisseur au niveau des artères pulmonaires lorsque comparées en fonction du phénotype valvulaire aortique (P = 0.94). Il n'y avait aucune différence au niveau des propriétés tensiles parmi les aortes et les artères pulmonaires lorsque comparées en fonction du phénotype valvulaire. Lorsque comparées en fonction de leur indication chirurgicale, les artères pulmonaires de patients ayant une régurgitation aortique pure étaient moins rigides que leur contre-partie (P = 0.002). Il n'y avait aucune différence au niveau du nombre de lamelles élastiques entre les spécimens d'artère pulmonaire en fonction du phénotype valvulaire aortique (Tricuspide, bicuspide ou unicuspide), ni entre les spécimens aortiques. CONCLUSION: Aucune différence significative ne fut observée au niveau des propriétés biomécaniques des artères pulmonaires lorsque comparées selon leur phénotype valvulaire aortique associé. / The Ross procedure: biomechanical properties of the pulmonary artery according to aortic valve phenotype Pierre Olivier Dionne, Evan Wener, Alexander Emmott, Raymond Cartier, Rosaire Mongrain, Richard Leask and Ismail El-Hamamsy OBJECTIVES: The aim of this study is to determine whether patients undergoing the Ross procedure with bicuspid aortic valves have different pulmonary artery biomechanical properties from those with tricuspid valves. METHODS: Thirty-two pulmonary arteries and 20 aortas were obtained from patients undergoing the Ross procedure at the time of surgery, from a cohort of 32 patients. Histological analysis and ex vivo equi-biaxial tensile testing completed within 8 hours of surgery were used to evaluate differences in patient groups and between the pulmonary artery and the ascending aorta. RESULTS: There was no difference in thickness among pulmonary arteries when compared according to aortic valve phenotype (P = 0.94). There was no difference in the tensile tissue properties among aortas and pulmonary arteries when compared according to aortic valve phenotype, in either the circumferential or longitudinal axis. When compared according to the main surgical indication, pulmonary artery walls from patients with pure aortic regurgitation were less stiff than their counterparts (P = 0.002). There was no difference in the number of elastic lamellae in pulmonary artery specimens from the three different aortic valve phenotypes (Tricuspid, bicuspid or unicuspid), as well as in the aortic specimens. CONCLUSION: No significant differences were observed in the biomechanical properties of pulmonary arteries when compared according to aortic valve phenotype.
95

Konstrukční návrh precizního manipulátoru / Conceptual design of a precision manipulator

Stuchlík, Petr January 2018 (has links)
This diploma thesis deals with the problems of analysis and the subsequent design of a precision manipulator used as a microscope table. The first part od the final thesis deals with the problems associated with the movement of the test sample within the electron microscope. Subsequently, possiblle design variants were proposed, further developing the next steps fot the correctness and functionality of manipulator. The individual force loads of the components were calculated. The result of the work was constructed as a CAD model with subsequent transfer to the assembly drawing.
96

Analýza výměníku tepla / Analysis of heat exchanger

Nosek, Miroslav January 2012 (has links)
The diploma thesis is focusing on research of possible damage mechanism of U-tubes in a heat exchanger placed within a gas waste incinerator unit in a factory dealing with chemicals manufacturing. In the first phase of the research, in which a thermo – hydraulic calculation is being made, a specialized software tool HTRI Xchanger Suite® v6.00 is used. Using the software it is possible to simulate certain operational conditions in which the heat exchanger operates. The output from the first phase of the solution is to obtain a set of temperatures of the tube material throughout the length of the tubes. These data are consequently used in the second phase of the analysis. The second phase of the analysis is dealing with thermal lenght dilatation differences assessment between tubes in the tube bundle as a predected reason of oversize tension formed in tube material and damage following afterwards. Conclusions of the calculation made in the second phase of the analysis are then checked by calculation via ANSYS Workbench 11.
97

Påverkan av koffein på blodtryck, flödeshastighet och lumendiameter i arteria carotis communis : En ultraljudsundersökning inom klinisk fysiologi / Effect of caffeine on blood pressure, flow velocity and lumen diameter in arteria carotis communis : An ultrasound examination in clinical physiology

Abbas, Ali January 2022 (has links)
Ultraljudsundersökningar av arteria carotis communis (CCA) utförs med ultraljud vid bedömning av kärlförändringar och flödeshastigheter (FH) samt utredning av sjukdomar i CCA. Lumendiameter (LD) i CCA är en markör för riskfaktorer som leder till stroke, hjärtinfarkt och ateroskleros. Syftet med den aktuella studien är att studera om det sker någon vasoaktiv förändring i CCA vid konsumtion av koffein hos unga vuxna. Det var 33 försökspersoner som delades upp i grupper beroende på deras koffeinkonsumtionsvanor och undersöktes med ultraljud. Försökspersonerna hade innan undersökning inte konsumerat koffein på 12 timmar. Undersökningen utfördes innan konsumtion av koffeindryck och 45 minuter efter koffeinkonsumtion. En signifikant skillnad efter konsumtion av koffein påvisades i lågkonsument gruppen (grupp 1) (p.0,06) och högkonsument gruppen (grupp 3) (p=0,05). En positiv korrelation mellan LD innan och efter konsumtion (r=0,955; p &lt;0,01) samt FH innan och efter konsumtion (r=0,393; p &lt;0,01) av koffein kunde påvisas. Nyckelord: Carotisduplex, Kaffe, Vasoaktiv, CCA.
98

Étude des effets d'une boisson riche en polyphénols sur la fonction endothéliale et la performance chez des athlètes de haut niveau

Labonté, Kim 17 April 2018 (has links)
Une réduction du débit sanguin lors d'activités physiques de haute intensité limite de façon importante l'oxygénation musculaire et a donc un impact majeur sur la performance dans plusieurs disciplines sportives. Bien que la consommation de polyphenols augmente de façon aigiie la vasodilatation artérielle chez des individus sédentaires, on ignore si cette vasodilatation se produit aussi chez les athlètes. La question qui sera développée dans ce mémoire est de savoir si la consommation de polyphenols améliore la vasodilatation médiée par le débit sanguin (FMD) et la performance à l'effort chez des athlètes de haut niveau. Les résultats de cette étude démontrent que la consommation d'une boisson riche en polyphenols améliore de façon aigiie la fonction endothéliale d'athlètes telle que mesurée par la FMD. Bien qu'une formulation riche en polyphenols ne modifie pas la performance lorsque consommée de façon aigiie avant un test maximal sur vélo, elle diminue toutefois la concentration sanguine de lactate suite à l'effort. Elle pourrait donc faciliter la récupération lorsque consommé avant un exercice intense.
99

Comportement du béton au jeune âge sous différentes conditions thermiques

Bouhlel, Mohamed 18 April 2018 (has links)
Les matériaux cimentaires sont utilisés de plus en plus dans le domaine de la construction civile. Plusieurs recherches expérimentales sont réalisées dans le but de mieux comprendre les mécanismes pilotant le comportement des bétons et d’identifier les facteurs responsables afin d’en assurer à la fois une meilleure durabilité et une bonne résistance. Or, les bétons dits de haute performance sont susceptibles à se fissurer depuis les premières heures suivant l’initiation de la réaction d’hydratation. La durabilité des bétons est ainsi affectée. Ceci constitue un défi d’actualité. C’est dans cette optique que la présente recherche a été initiée. Le terme jeune âge représente les premiers jours, voire les premières heures, suivant l’amorcement de la réaction d’hydratation des grains de ciments. À l’heure actuelle, il n’existe pas de procédure ni de montages expérimentaux « normalisés » permettant d’évaluer le comportement des bétons depuis le jeune âge. Le Centre de recherche sur les infrastructures en béton (CRIB) a développé un dispositif expérimental qui permet de simuler le comportement des bétons sous des conditions de restrictions des déformations. Le montage, appelé montage de retrait restreint à déformations différées (R2D2), a été amélioré dans le cadre de cette étude afin de permettre d’examiner l’influence de la température sur le comportement des bétons au jeune âge. Plusieurs bétons ont été formulés et testés en se basant sur trois types de ciments. Cinq rapports eau/ciment ont été testés et plusieurs profils thermiques ont été appliqués. L’influence du rapport eau/ciment, de la composition minéralogique et de la température sur le comportement ont été investis plus en profondeur. Le détail des résultats de cette étude expérimentale est présenté dans les sections qui suivent. / Cementitious materials are used increasingly in the field of civil construction. Several experimental investigations are conducted to better understand the mechanisms controlling the behaviour of concrete and identify the factors responsible to ensure both durability and strength. But the so-called high performance concretes are likely to crack in the first hours after the initiation of the hydration reaction. The durability of concrete is thus affected. This constitutes a challenge for today. This research has been initiated with this perspective in mind. The term young age represents the first days, even the first few hours following the initiation of the reaction of hydration of cement grains. Currently, there is no procedure or experimental setups standardized to assess the behaviour of concrete from an early age. The Research Center on Concrete Infrastructures (CRIB) has developed an experimental device that simulates the behaviour of concrete under conditions of restricted deformation. The assembly, called the assembly for restrained shrinkage deformations (R2D2) was improved as part of this study to help examine the influence of temperature on the behaviour of concrete at early age. Several concrete were formulated and tested based on three types of cements. Five water /cement ratios were tested and several thermal profiles were applied. The influence of the water /cement ratio, the mineralogical composition of cement and the effect of the temperature on the concrete behaviour have been investigated in more depth.
100

Les effets d'une supplémentation en huile de poisson et/ou jus de canneberges sur la fonction endothéliale chezl'homme

Riopel-Meunier, Julie 13 April 2018 (has links)
Les travaux présentés dans ce mémoire ont pour but d'examiner les effets d'une supplémentation en huile de poisson (FO) avec ou sans consommation en jus de canneberges (JC) sur la vasodilatation de l'artère brachiale induite par une hyperémie (FMD) provoquée chez l'homme. Pour cela, 86 hommes ont été divisés aléatoirement en 4 groupes: 1) placebo, n=16, 2) 500mL/jour JC, n=23, 3) 2.3g/jour FO, n=22 ~t 4) FO+JC, n=25. La FMD a été mesurée avant et après l'intervention par une échographie de l ' artère brachiale. Les mesures ont été effectuées au repos ainsi que 60 et 90 secondes suivant l'hyperémie. Nous avons observé que la valeur au repos, FMD60 et FMD90 étaient significativement différentes entre le début et la fin uniquement pour le groupe ayant consommé du JC. Toutefois aucune différence significative n'a été observée pour les groupes ayant consommé des FO et FO*JC. Nous avons aussi observé que les changements de FMD60 et FMD90 ainsi que celles avec nitroglycérine sublinguale étaient négativement associés avec le diamètre artériel brachial.

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