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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.
41

A melatonina protege o pulmão na síndrome hepatopulmonar experimental

Dal Bosco, Adriane January 2017 (has links)
Base teórica: A Síndrome Hepatopulmonar (SHP) caracteriza-se por uma tríade clínica que inclui doença hepática, anormalidades em trocas gasosas e presença de dilatações vasculares pulmonares, sendo a obstrução prolongada do ducto biliar utilizada em modelos experimentais de cirrose biliar secundária que leva a reações inflamatórias agudas, podendo, ainda, ocasionar alterações sistêmicas. Animais com cirrose induzida experimentalmente por ligadura de ducto biliar (LDB) apresentam aumento do estresse oxidativo no tecido hepático, mas a inter-relação com o tecido pulmonar ainda não está bem esclarecida. O estresse oxidativo desempenha papel central na patogênese e na progressão de doenças crônicas, e o uso de antioxidantes tem sido proposto como agente terapêutico para compensar danos sistêmicos e hepáticos. Em estudos em que a utilização da melatonina foi comparada com a utilização de outros antioxidantes conhecidos como as vitaminas C e E, tal componente mostrou-se mais eficiente na redução do estresse oxidativo/nitrosativo, demonstrando que a melatonina atua como potente antioxidante. Objetivo: A presente tese teve como objetivo investigar o efeito do antioxidante Melatonina sobre o tecido pulmonar no modelo experimental de Síndrome Hepatopulmonar por ligadura de ducto biliar. Métodos: O trabalho está dividido em três partes: Parte I- Artigo de revisão intitulado “Hepatopulmonary Syndrome: Oxidative Stress and Physical Exercise,” enviado para publicação no periódico European Medical Journal; Parte II- Artigo original intitulado “Efeitos da melatonina sobre o tecido pulmonar no modelo experimental de síndrome hepatopulmonar”, enviado para o periódico Jornal de Pneumologia; Parte III- Artigo original intitulado “Efeitos da melatonina sobre o tecido hepático e pulmonar em animais com síndrome hepatopulmonar por ligadura do ducto biliar”, a ser enviado para o periódico Digestive Diseases and Sciences. Foi utilizado o modelo de cirrose biliar secundária, induzida pelo modelo de ligadura de ducto biliar (LDB), com ratos machos Wistar, pesando ± 300 gramas, divididos em quatro grupos: CO (controle), CO+MLT, SHP e SHP+MLT. Os animais foram tratados com MLT a partir do 15° dia e com LDB até o 28° dia. No 29° dia, mediante administração de fármacos anestésicos, foram coletados sangue, fígado, pulmão e fêmur. Resultados: Nos artigos II e III, ao se avaliar as transaminases, observou-se aumento significativo nas enzimas ALT, AST e FA no grupo SHP quando comparadas aos grupos controles, o que determina a presença de doença hepática. Posteriormente à administração da 7 melatonina, houve diminuição significativa do grupo SHP+MLT quando comparado ao grupo SHP na avaliação da lipoperoxidação, atividade das enzimas Catalase (CAT), superóxido dismutase (SOD) e glutationa Peroxidade (GPx), bem como na de Nitritos/Nitratos (NO2/NO3) e no sistema inflamatório, quando da avaliação da expressão da Óxido Nítrico Sintase Induzível (iNOS) e da região p65 do fator de transcrição nuclear-kB (NF-kB). Também houve diferença na gasometria arterial e na histologia do tecido pulmonar pelas técnicas de Hematoxilina e Eosina e Picrosírius, especialmente no diâmetro dos vasos pulmonares. Ao avaliar o dano ao DNA pelo Ensaio Cometa, foi observado aumento do índice e da frequência de dano no grupo SHP, com redução após o uso da MLT. Conclusão: Os resultados sugerem efeito protetor da melatonina no tecido hepático e pulmonar, no modelo de Síndrome Hepatopulmonar por ligadura de ducto biliar. / Background: Hepatopulmonary syndrome (HPS) is clinically characterized by a combination of liver disease, gas exchange abnormalities, and pulmonary vascular dilation. Prolonged biliary duct obstruction was used in experimental models of secondary biliary cirrhosis leading to acute inflammatory reactions and possibly to systemic changes. Animals with cirrhosis experimentally induced by biliary duct ligation (BDL) showed increased oxidative stress in liver tissue, but the lung tissue has not been investigated yet. Oxidative stress has a key role in the pathogenesis and progression of chronic diseases, and antioxidants have been proposed as therapeutic agents to compensate for systemic and liver damages. In studies comparing melatonin with other known antioxidants such as vitamins C and E, melatonin was found to be more efficient in reducing oxidative/nitrosative stress, showing that it is a potent antioxidant. Objective: The present doctoral dissertation aimed to investigate the effect of the antioxidant melatonin on lung and liver tissues in an experimental model of BDL-induced HPS. Methods: This dissertation is divided into three parts: Part I consists of the review article entitled “Hepatopulmonary Syndrome: Oxidative Stress and Physical Exercise,” which was submitted to the European Medical Journal; Part II consists of the original article entitled “Efeitos da melatonina sobre o tecido pulmonar no modelo experimental de síndrome hepatopulmonar”, which was submitted to Jornal de Pneumologia; and Part III consists of the original article entitled “Effects of melatonin on liver and lung tissues of animals with bile duct ligation-induced hepatopulmonary syndrome”, which will be submitted to Digestive Diseases and Sciences. A model of secondary BDL-induced biliary cirrhosis was used in male Wistar rats weighing ± 300 g and divided into four groups: control group (CG), CG+MLT, HPS, and HPS+MLT. Animals were treated with MLT or vehicle from day 15 to day 28 after BDL. On day 29, blood, liver, lung, and femur samples were collected after the administration of anesthetic drugs. Results: As for transminases, papers II e III found that there was a significant increase in enzymes ALT, AST e FA in the HPS group compared with the control groups, which indicates the presence of liver disease. The administration of melatonin led to a significant decrease in the HPS group compared with the control groups with regard to the following variables: lipid peroxidation; catalase, superoxide dismutase, and glutathione peroxidase activity; nitrite/nitrate ratio; and inducible nitric oxide synthase and p65 region of nuclear factor kappa B. There were also differences in blood gas analysis and histology of lung tissues as assessed by hematoxylin and eosin (HE) and picrosirius red staining, especially in the diameter of pulmonary vessels. The comet assay revealed an increase the index and frequency of DNA damage in the HPS group compared with the control groups, but these parameters were reduced with the use of melatonin in the HPS+MLT group. Conclusion: Results suggest that melatonin has a protective effect in liver and lung tissues using a BLD-induce HPS model.
42

Análise hemogasométrica do sangue venoso equino pré e pós-exercício

Gomes, Alice Giugno January 2013 (has links)
O presente trabalho foi realizado com o objetivo de verificar alterações do estado ácido-básico metabólico de equinos antes e após atividade física de intensidade máxima (corrida) através do exame hemogasométrico. Avaliou-se, ainda, a confiabilidade deste exame para o sangue armazenado a 4ºC durante doze horas. Duas amostras de sangue venoso foram coletadas de quinze animais clinicamente sadios, sendo a primeira coleta realizada com o animal em repouso e a segunda após o término da prova, e as mesmas foram divididas em dois grupos: Grupo I (GI) – pré-corrida e Grupo II (GII) – pós-corrida. As amostras de sete animais foram avaliadas imediatamente após a coleta, enquanto as amostras de oito animais foram mantidas sob-refrigeração a 4ºC (dentro do refrigerador) durante doze horas antes de serem analisadas. O sangue foi analisado para verificar os valores de pH, pCO2, TCO2, HCO3, BE, pO2, sO2 e Lactato. Os resultados grupos foram comparados através da análise de variância. O Teste T de Student foi utilizado para uma comparação das médias das avaliações das amostras analisadas imediatamente ou doze horas após a coleta. Foram observadas diferenças estatísticas para todas as variáveis analisadas pré e pós-exercício, verificando-se valores significativamente menores para pH, pCO2, BE, HCO3 e TCO2, e valores significativamente maiores para sO2, pO2 e lactato nas amostras coletadas após a corrida em relação aos valores obtidos para as mesmas variáveis com os animais em repouso. Verificou-se, também, diferença significativa entre os resultados obtidos imediatamente após a coleta em relação àqueles encontrados nas amostras refrigeradas para todas as variáveis analisadas, tanto com os animais em repouso como após o exercício, exceto para a pCO2 após o exercício. Esses resultados indicam que o exercício físico, bem como o armazenamento das amostras de sangue, promovem alterações nos parâmetros avaliados no presente trabalho. / This study was carried out to verify changes in the metabolic acid-base status of equines before and after physical activity of maximum intensity (race) using blood gas analysis. We also evaluated the reliability of this test for the blood stored at 4 ° C for twelve hours. Two venous blood samples were collected from fifteen clinically healthy animals, the first collection with the animal at rest and the second after the race, and then divided into two groups: Group I (GI) - pre-race and group II (GII) - post-race. Samples of seven animals were evaluated immediately after collection, while samples from eight animals were kept under refrigeration at 4ºC (in a refrigerator) for twelve hours before being analyzed. The blood was analyzed to check pH, pCO2, TCO2, HCO3, BE, pO2, sO2 and lactate values. The results of the groups were compared by analysis of variance. Student's t test was used for comparison of the means of the evaluations of the samples analyzed immediately or twelve hours after collection. Statistical differences were observed for all variables analyzed before and after exercise, showing significantly lower values for pH, pCO2, BE, HCO3 and TCO2, and significantly higher values for sO2, pO2 and lactate in the samples collected after the race compared to the values obtained for the same variables with the animals at rest. There was also a significant difference between the results obtained immediately after collection compared to those found in the refrigerated samples for all analyzed variables, both with the animals at rest and after exercise, except for pCO2 after exercise. These results indicate that exercise and storage of blood samples promote changes in the parameters evaluated in this study.
43

Ventilação mecânica em bezerros clonados: bases para sua utilização nos distúrbios respiratórios de neonatos bovinos / Mechanical ventilation in cloned calves: Bases for use in respiratory disorders of newborns calves

Melina Marie Yasuoka 05 December 2016 (has links)
A monitorização após o parto é necessária a manutenção da vida nos bezerros clonados. É imperativo que os protocolos e procedimentos, bem como a avaliação clínica dos sistemas cardiovascular e respiratório sejam aprimorados para a sobrevida dos clones. As avaliações que permitam averiguar a capacidade de oxigenação dos pulmões são de crucial importância na assistência ao neonato, sendo que para essa finalidade tem-se recomendado a utilização da hemogasometria. O estudo foi dividido em quatro capítulos, sendo o 1 º Capítulo: Comparação das diferenças da adaptação neonatal de bezerros da raça Nelore(n=10) e de bezerros da raça Holandesa(n=10) nas trocas gasosas e nos parâmetros hemodinâmicos obtidos por meio do cateter de Swan-Ganz, o 2 º Capítulo: Avaliação da hemodinâmica e da hemogasometria de bezerros clonados(n=3), e o 3º Capítulo: Relato da utilização da ventilação mecânica não invasiva - modo CPAP- no tratamento de hipóxia neonatal em 10 bezerros e o 4º Capítulo: Avaliação hemodinâmica e hemogasométrica de bezerros neonatos com distúrbios respiratórios submetidos a ventilação mecânica não invasiva com mascara facial modo ventilatório CPAP (n=12). O objetivo deste trabalho será padronizar a utilização de ventiladores em bezerros neonatos dando o suporte respiratório necessário, avaliando hemodinâmicas da pressão da artéria pulmonar, freqüência cardíaca, débito cardíaco por meio da utilização do cateter de Swan-Ganz, a hemogasometria de sangue arterial para avaliação dos distúrbios respiratórios e obtenção dos valores de normalidade dos parâmetros, além de conhecer a adaptação neonatal das raças Nelore e holandesa. Foram determinadas média pressão artéria pulmonar, pressão artéria pulmonar ocluída, pressão ventrículo direito, pressão átrio direito, temperatura, pH, pCO2, pO2, HCO3, BE, SO2. Os animais foram ventilados modo CPAP- ventilação mecânica não invasiva com mascara facial com pressão positiva no final da expiração(PEEP). / Monitoring after calving is required for the maintenance of life in cloned calves. It is imperative that protocols and procedures, as well as the clinical assessment of cardiovascular and respiratory systems are improved for the survival of clones. Evaluations in order to verify the oxygenation capacity of lungs are crucial in neonatal care, and for this purpose has recommended the use of blood gas analysis. The study was divided into four chapters, the 1st chapter: Comparison of differences in neonatal adaptation of Nellore calves (n = 10) and Holstein calves (n = 10) in gas exchange and hemodynamic parameters obtained by through the Swan-Ganz, the 2nd Chapter: hemodynamic evaluation and blood gas analysis of cloned calves (n = 3), and the 3rd Chapter: Reporting the use of noninvasive mechanical ventilation - CPAP- in the treatment of neonatal hypoxic 10 calves and Chapter 4: hemodynamic evaluation and hemogasometric of newborn calves with respiratory disorders underwent noninvasive ventilation with face mask ventilation mode CPAP (n = 12). The purpose of this study is to standardize the use of mechanical ventilators in newborn calves giving the required respiratory support, evaluating hemodynamic pulmonary artery pressure, heart rate, cardiac output by using of the Swan-Ganz catheter, arterial blood gas analysis to evaluation of respiratory disorders and obtaining the parameters normal values, and know the neonatal adaptation of Nellore and Hostein Frisian races. They were determined means of pulmonary artery pressure, pulmonary artery wedge pressure, right ventricular pressure, right atrial pressure, temperature, pH, pCO2, pO2, HCO 3, BE, SO 2. The animals were ventilated CPAP- noninvasive ventilation mode with face mask with positive pressure at the end of expiration (PEEP)
44

Improved methods for enrichment of organic ultra trace components for analysis by gas chromatography

Kloskowski, Adam January 2003 (has links)
This thesis describes some new methods for analysis oforganic trace components from air and water by gaschromatography. The work is particularly focused on thedevelopment of new technologies for analyte enrichment, usingsorbent-based concepts. Short lengths of open tubular columnswere examined for their potential use as denuders.Polydimethylsiloxane-based stationary phases as well as anadsorbent-based column were evaluated in an equilibrium mode oftrapping. For the analytes selected, detection levels in theppb range were obtained (Paper I). A new, fully automated set-up for analysis of organic tracecomponents in aqueous samples has been developed (Paper II).The work combines specific advantages of the solid phase microextraction (SPME) technology and stir bar sorptive extractionconcept. Ultra trace components, down to 0.1 ppt could bedetected. Finally a simple method for preparation a new type ofultra thick film open tubular trap is described (Paper III).The traps are characterized by an irregular coating, and it wasdemonstrated that the performance characteristics of thesetraps were practically as good as of traps with a smooth,regular coating. The technology can be utilized in many areas,e.g. environmental monitoring, process analysis and otherfields dealing with analysis of trace organic volatiles ingaseous samples. <b>Keywords:</b>Organic trace components, volatiles, denuders,sorbent trapping, thick film trapping, open tubular traps,SPME, automation, water analysis, gas analysis, environmentalanalysis. / NR 20140805
45

Studies on the regulation of fat metabolism during endurance exercise / 持久運動時の脂肪代謝調節機構に関する研究

Fujitani, Mina 23 March 2015 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第19042号 / 農博第2120号 / 新制||農||1032(附属図書館) / 学位論文||H27||N4924(農学部図書室) / 31993 / 京都大学大学院農学研究科食品生物科学専攻 / (主査)教授 伏木 亨, 教授 保川 清, 教授 金本 龍平 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DGAM
46

How Much for Joint Action?Assessing the Cost of Working Together

Mayr, Riley C. January 2019 (has links)
No description available.
47

Dynamic metabolic changes observed in an LPS-induced systemic inflammation rat model using continuous long-term indirect calorimetry experiments / 長時間連続間接熱量測定によるLPS全身炎症ラットモデルを用いた代謝研究

Murata, Satoru 24 November 2023 (has links)
京都大学 / 新制・論文博士 / 博士(医学) / 乙第13578号 / 論医博第2300号 / 新制||医||1069(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 生田 宏一, 教授 中島 貴子, 教授 浅野 雅秀 / 学位規則第4条第2項該当 / Doctor of Medical Science / Kyoto University / DFAM
48

Design, Development and Validation of UC Film Cooling Research Facility

Kandampalayam Kandasamy Palaniappan, Mouleeswaran January 2017 (has links)
No description available.
49

Growth response and adaptability of acer rubrum and acer XFREEMANII cultivars to soil compaction

Fair, Barbara A. 13 July 2005 (has links)
No description available.
50

Dissolved Gas Analysis of Insulating Transformer Oil Using Optical Fiber

Overby, Alan Bland 08 June 2014 (has links)
The power industry relies on high voltage transformers as the backbone of power distribution networks. High voltage transformers are designed to handle immense electrical loads in hostile environments. Long term placement is desired, however by being under constant heavy load transformers face mechanical, thermal, and electrical stresses which lead to failures of the protection systems in place. The service life of a transformer is often limited by the life time of its insulation system. Insulation failures most often develop from thermal faults, or hotspots, and electrical faults, or partial discharges. Detecting hotspots and partial discharges to predict transformer life times is imperative and much research is focused towards these topics. As these protection systems fail they often generate gas or acoustic signals signifying a problem. Research has already been performed discovering new ways integrate optical fiber sensors into high voltage transformers. This thesis is a continuation of that research by attempting to improve sensor sensitivity for hydrogen and acetylene gasses. Of note is the fabrication of new hydrogen sensing fiber for operation around a larger absorption peak and also the improvement of the acetylene sensor's light source stability. Also detailed is the manufacturing of a field testable prototype and the non-sensitivity testing of several other gasses. The developed sensors are capable but still could be improved with the use of more powerful and stable light sources. / Master of Science

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