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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.
1

O volume do ba?o aferido atrav?s da resson?ncia magn?tica em adolescentes com sobrepeso e obesos ? maior do que em eutr?ficos

Cunha, Carol Fernandes Jerzewski Sotero da 30 March 2015 (has links)
Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2015-05-14T11:46:21Z No. of bitstreams: 1 468609 - Texto Parcial.pdf: 604351 bytes, checksum: e5d6c515e5cb4c04c6c2a0b0d144bb87 (MD5) / Made available in DSpace on 2015-05-14T11:46:22Z (GMT). No. of bitstreams: 1 468609 - Texto Parcial.pdf: 604351 bytes, checksum: e5d6c515e5cb4c04c6c2a0b0d144bb87 (MD5) Previous issue date: 2015-03-30 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Objective: to evaluate the volume of the spleen in eutrophic and obese adolescents through MR and to compare it between the two groups. Secondarily, these measurements were correlated with the age, sex, weight, BMI and height of the patients in each group. Material and Methods: a cross-sectional, observational study, part of an umbrella project, performed during January and February 2015 in a tertiary hospital. The following were measured: the maximum width (W) and thickness (T) of the spleen in the T1 axial sequence and the maximum longitudinal diameter (LD) in the T2 coronal sequence from MR exams of the upper abdomen performed on 50 adolescents between the ages of 16 and 18. The adolescents were divided into two groups: eutrophic subjects (BMI<25) and overweight/obese subjects (BMI ?25). We calculated the volume of each patient?s organ through the conventional formula to calculate the volume of an elongated ellipsoid (0.524 x W x T x LD). Anthropometric data (weight, BMI, height and age) were obtained from the umbrella project?s database. We used Pearson or Spearman correlation coefficients to correlate the quantitative variables with each other and Student?s t-test to compare the averages for independent samples. Results: Twenty-six patients (52.0%) were male; the average age was 16.7 years old, and standard deviation was 0.8 years; 31 patients (82.0%) had a BMI<25 (eutrophic) and 19 (38%) had a BMI?25 (overweight/obese). There was a statistically significant difference between the groups for the spleen?s width (p=0.008) and volume (p=0.020), which were larger in the overweight/obese group. For the eutrophic group, the averages for the maximum width (p=0.016), for the maximum longitudinal diameter (p <0.001) and for the volume of the spleen (p=0,001) were higher in the males than in the females in a statistically significant way. There was no statistically significant difference in the measurements between the sexes for the overweight/obese group. Height showed a stronger correlation than weight with the volume, maximum width and maximum longitudinal diameter of the spleen in the eutrophic group and a correlation of the same intensity with weight for all the measurements of the spleen in the overweight/obese group. Conclusion: This study suggests that the volume of the spleen as determined by MR is greater in overweight or obese adolescents than it is in eutrophic adolescents. More research is needed to evaluate the reproducibility of our results on the rest of the adolescent population, given the narrow age band used for our study. / Objetivo: avaliar o volume do ba?o em adolescentes eutr?ficos e obesos atrav?s da RM e compar?-lo entre os dois grupos. Secundariamente, estas medidas ser?o correlacionadas com a idade, o sexo, o peso, o IMC, e a altura dos pacientes em cada um dos grupos. Material e M?todos: estudo observacional transversal, parte de um projeto guarda-chuva, realizado em janeiro e fevereiro de 2015 em um hospital terci?rio; foram realizadas as medidas da largura m?xima (L) e da espessura (E) do ba?o na sequ?ncia axial T1 e do di?metro longitudinal m?ximo (DL) na sequ?ncia coronal T2 de exames de RM do abd?men superior de 50 adolescentes entre 16 e 18 anos divididos em dois grupos: eutr?ficos (IMC<25) e sobrepeso/obesos (IMC ?25); o volume do ?rg?o de cada paciente foi calculado atrav?s da f?rmula convencional para calcular o volume de um elips?ide alongado (0,524 x L x E x DL); os dados antropom?tricos (peso, IMC, altura e idade) foram obtidos do banco de dados do projeto guarda-chuva; para correlacionar as vari?veis quantitativas entre si foram utilizados os coeficientes de correla??o de Pearson ou Spearman e para comparar as m?dias foi utilizado o teste t de Student para amostras independentes. Resultados: 26 pacientes (52,0%) eram do sexo masculino; a m?dia de idade foi de 16,7 anos e o desvio-padr?o de 0,8 anos; trinta e um pacientes (82,0%) tinham IMC<25 (eutr?ficos) e 19 (38%) tinham IMC?25 (sobrepeso/obesos); a largura (p=0,008) e o volume do ba?o (p=0,020) apresentaram diferen?a estatisticamente significativa entre os grupos, sendo maiores no grupo sobrepeso/obesos; a m?dia da largura m?xima (p=0,016), do di?metro longitudinal m?ximo (p <0,001) e do volume do ba?o (p=0,001) foram maiores no sexo masculino do que no feminino de forma estatisticamente significativa no grupo dos eutr?ficos e n?o houve diferen?a significativa entre os sexos no grupo sobrepeso/obesos; a altura apresentou correla??o mais forte do que o peso com o volume, a largura m?xima e o di?metro longitudinal m?ximo do ba?o no grupo dos pacientes eutr?ficos e correla??o de mesma intensidade que o peso com todas as medidas do ba?o no grupo sobrepeso/obesos. Conclus?o: Este estudo sugere que o volume do ba?o aferido atrav?s da RM ? maior em adolescentes com sobrepeso e obesos do que em adolescentes eutr?ficos. S?o necess?rios mais trabalhos que avaliem a reprodutibilidade dos nossos resultados no restante da popula??o pedi?trica, tendo em vista a estreita faixa et?ria do nosso estudo.
2

Papel do ba?o na resposta inflamat?ria cerebral em modelo experimental de epilepsia em ratos tratados com c?lulas mononucleares de medula ?ssea

Silva, Daniele Vieira da 27 February 2015 (has links)
Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2015-08-17T19:56:49Z No. of bitstreams: 1 473525 - Texto Parcial.pdf: 378184 bytes, checksum: b680d905cd5090c77c92df187b59241d (MD5) / Made available in DSpace on 2015-08-17T19:56:49Z (GMT). No. of bitstreams: 1 473525 - Texto Parcial.pdf: 378184 bytes, checksum: b680d905cd5090c77c92df187b59241d (MD5) Previous issue date: 2015-02-27 / Epilepsy comprehends a category of syndromes characterized by spontaneous and recurrent crises (SRCs), which are a result of intense electric activity, synchronized and rhythmic of neuronal populations of the central nervous system (CNS), and of excessive excitability in the absence of a toxic-metabolic condition or fever 1 2, 3. Experimental studies have shown that SE induction in rodents provokes pronounced inflammatory cerebral reaction involving endothelial cells, glia, and neurons4, 5. Our group has shown that intravenous bone marrow cells administration following lithium-pilocarpine SE induction reduces SRCs, improves cognitive function, and modulates the production of pro-inflammatory cytokines6, 7. The spleen is important to induce cerebral inflammatory response and also is an important target for stem cell intervention therapies8. Splenectomy before a cerebrovascular accident (CVA) significantly reduces the infarction size in the brain9. Moreover, it has been demonstrated that in the pilocarpine model splenectomy decreases the severity of crises, the time to SE onset, and the mortality rate caused by SE10. The aim of the present work was investigating the importance of the interaction between bone marrow mononuclear cells (BMC) and the spleen in epileptic rats. As a result, the animals treated with BMC presented a better capability of memory retrieval in the Morris aquatic maze (MAM) when compared to the treated animals without the spleen. Besides, the treatment did not present the potential of reducing the levels of IL-1 ? or of increasing the levels of IL-10 in the serum and hippocampus of treated rats without the spleen. In conclusion, the work suggests that the spleen could be involved in the therapeutic effect promoted by BMC transplant. / A epilepsia compreende uma categoria de s?ndromes que se caracterizam por crises espont?neas e recorrentes (CERs), que s?o resultados de disparos el?tricos intensos, sincronizados e r?tmicos de popula??es neuronais no sistema nervoso central (SNC) e de excitabilidade excessiva, na aus?ncia de condi??o t?xico-metab?lica ou febril.1 2, 3 Pesquisas experimentais mostram que a indu??o do Status Epil?pticos (SE) em roedores provoca rea??o inflamat?ria cerebral pronunciada envolvendo as c?lulas endoteliais, glia e neur?nios.4, 5 Nosso grupo mostrou que a administra??o de c?lulas da medula ?ssea por via intravenosa depois da indu??o do SE por l?tio-pilocarpina ? capaz de reduzir as CERs, melhorar a fun??o cognitiva e modular a produ??o de citocinas pr?-inflamat?rias.6, 7 O ba?o ? importante na indu??o da resposta inflamat?ria cerebral e tamb?m ? um alvo importante para a interven??o de c?lulas-tronco.8 A esplenectomia antes do acidente vascular cerebral (AVC) reduz significativamente o tamanho do infarto no c?rebro.9 Foi tamb?m demonstrado que no modelo da pilocarpina, a esplenectomia diminuiu a gravidade das crises, o tempo para o in?cio do SE, e a taxa de mortalidade causada pelo SE.10 O objetivo do presente trabalho ? investigar a import?ncia da intera??o entre c?lulas mononucleares da medula ?ssea (CMMO) e o ba?o em ratos epil?pticos. Como resultado do trabalho nossos animais tratados com as CMMO apresentaram melhor capacidade de reter a mem?ria no teste do LAM quando comparados aos animais tratados sem o ba?o. Al?m disso, nesses animais o tratamento n?o teve o potencial de reduzir as taxas de IL-1 ? no soro e nem de aumentar os n?veis de IL-10 no soro e no hipocampo de ratos tratados e sem o ba?o. Concluindo, o trabalho sugere que o ba?o possa estar envolvido modulando a cascata inflamat?ria no efeito terap?utico promovido pelo transplante de CMMO.
3

Medidas morfofuncionais e caracter?sticas da carne e v?sceras de bovinos castrados Nelore e F1 Nelore x Sindi. / Morphologic measurements end characteristics of meat and organs of Nellore and F1 Nellore x Sind castrated Cattle

Costa, Dorival Pereira Borges da 05 May 2006 (has links)
Made available in DSpace on 2016-04-28T14:59:42Z (GMT). No. of bitstreams: 1 2006-Dorival Pereira Borges da Costa.pdf: 138385 bytes, checksum: 2fb301a9fde86d26ed524784415f0c83 (MD5) Previous issue date: 2006-05-05 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The evaluation of the morphologic measurements, meat quality and weight of the organs of two groups of eight steers Nellore and F1 Nellore x Sind, males castrated, raised in confinement and slaughtered with 36 and 48 were the objective of this study. The experimental design was a completely randomized in factorial arrangement 2 (two genetic groups) x 2 (two ages). There was not interaction between genetic group and age for any characteristics studied. By the analysis of morphologic measurements, there was not difference (P>0,05) for depth of chest just behind elbow joint, heart girth, rump height and width, ischium distance, rump length, body length, big thigh thickness, conformation, anamorphogenesis and Baron index. While the Nellore x Sind had higher (P<0,05) height withers (139,5 vs 136,5 cm) than Nellore, the Nellore cattle had a greater (P<0,05) compactness (12,7 vs 11,6). There was not influence (P>0,05) of the genetic group and age for the weight of digestive tract, kidneys, liver and lungs. Nellore animals had higher (P<0,05) heart weight (1,6 vs 1,2 kg) and spleen (1,1 vs 0,9 kg) than F1 Nellore x Sind cattle. The fat colour, luminosity and yellow intensity were similar (P>0,05) for both genetic groups and age. However, red intensity in fat was higher (P<0,05) in Nellore (8,5 vs 7,4) than F1 Nellore x Sind cattle. Animals with 36 months had higher (P<0,05) red intensity in fat (8,5 vs 7,3) than 48 months. The genetic group and age did not influence (P>0,05) moisture, protein, fat and mineral contents of the meat, cooking losses, luminosity, meat red and yellow intensity. It was concluded that Nellore x Sind promote a reduction on heart and spleen weight and no alterations in the most meat characteristics studied. The height and compactness are greater in Nellore and F1 Nellore x Sind. With exception of the greater red intensity in fat, the age not influenced others characteristics studied. / Objetivou-se com esta pesquisa realizar a avalia??o das medidas morfofuncionais, da qualidade da carne e das caracter?sticas das v?sceras de dois grupos de oito bovinos machos castrados Nelore e F1 Nelore x Sindi, terminados em confinamento e abatidos com 36 e 48 meses de idade. O delineamento experimental foi o inteiramente casualizado em esquema fatorial 2 (dois grupos gen?ticos) x 2 (duas idades). N?o houve intera??o entre grupo gen?tico e idade para nenhuma das caracter?sticas estudadas. As vari?veis morfofuncionais, n?o diferiram significativamente (P>0,05) para altura tor?cica, per?metro tor?cico, altura da garupa, largura da garupa, dist?ncia dos ?squios, comprimento da garupa, comprimento do corpo, espessura do cox?o, conforma??o, anamorfose e ?ndice de Baron. Enquanto os bovinos F1 Nelore x Sindi possuem (P< 0,05) maior altura (139,5 vs 136,5 cm), os Nelore tiveram maior (P<0,05) compacidade (12,7 vs 11,6). N?o houve influ?ncia (P>0,05) do grupo gen?tico e da idade para o peso do trato digestivo, rins, f?gado e pulm?es. Animais Nelore t?m maior (P<0,05) peso do cora??o (1,6 vs 1,2 Kg) e do ba?o (1,1 vs 0,9 Kg) do que bovinos F1 Nelore x Sindi. A cor da gordura, a luminosidade e a intensidade do amarelo foram semelhantes (P>0,05), tanto para grupos gen?ticos quanto para idade. Entretanto, a intensidade do vermelho na gordura foi maior (P<0,05) nos bovinos Nelore (8,5 vs 7,4) do que nos F1 Nelore x Sindi. Os animais de 36 meses possuem maior (P<0,05) intensidade do vermelho na gordura (8,5 vs 7,3) do que os de 48 meses. O grupo gen?tico e a idade n?o influenciaram (P>0,05) nos teores de umidade, prote?na, gordura e minerais, bem como a perda pelo cozimento, luminosidade, intensidade do vermelho e amarelo da carne. Conclui-se que os produtos do cruzamento Nelore x Sindi possuem menor peso do cora??o e ba?o e n?o t?m altera??o na maioria das caracter?sticas da carne estudadas. A altura e a compacidade ? maior nos Nelore e F1 Nelore x Sindi. Com exce??o da maior intensidade do vermelho na gordura e na idade n?o causou influ?ncia nas demais caracter?sticas estudadas.
4

Correction de fronts d'onde de faisceaux lasers impulsionnels par mélange d'ondes photoréfractif.

Mager, Loic 10 November 1994 (has links) (PDF)
Nous avons démontré que la correction de fronts d'onde de faisceaux lasers impulsionnels (nanoseconde) pouvait être réalisée par mélange d'ondes dans un cristal photoréfractif. Nous avons commence par déterminer le matériau photoréfractif le mieux adapte pour cette application. Pour des raisons d'efficacité photoréfractive et de tenue en puissance, notre choix s'est porte sur le titanate de baryum. Cela a conditionne le choix de la longueur d'onde utilisée (532 nm) pour cette démonstration. Nous avons étudié un premier dispositif de correction base sur le transfert d'énergie d'un faisceau fort vers un faisceau faible qui, par mélange d'ondes photoréfractif, peut être obtenu sans qu'il y ait de transfert de phase. Dans cette étude nous avons mesure les variations de l'amplification en fonction de différents paramètres (cohérence temporelle, rapport des énergies des faisceaux) et observe les variations de l'effet photorefractif en fonction de la densité de puissance dans le titanate de baryum. Nous avons aussi démontré la correction des déformations introduites par un objet de phase et cela pour différentes densités d'énergie incidente. Une deuxième méthode de correction est basée sur la compensation d'un aberrateur de phase par double passage. On a commence par préciser la notion de conjugaison de phase. Puis, nous avons étudié en particulier un miroir a conjugaison de phase auto pompe, l'oscillateur a boucle de réaction, qui fonctionne sur le principe du mélange a quatre ondes dans un cristal photoréfractif. Nous avons montre expérimentalement que des transformations des faisceaux dans la boucle de réaction améliorent la qualite de la conjugaison de phase et nous avons réalisé la compensation d'objets de phase par double passage en régime impulsionnel. La dernière partie est consacrée a l'étude comparative des deux dispositifs tels qu'ils pourront être mis en oeuvre pour la correction dynamique des lentilles thermiques dans les amplificateurs lasers solides.
5

Gyromètre a fibre a double conjugaison de phase - étude d'un nouveau matériau photorefractif - réalisation d'un démonstrateur .

Bernhardt, Sylvie 28 September 2001 (has links) (PDF)
Le remplacement de la fibre monomode a maintien de polarisation par de la fibre monomode standard dans les gyroscopes a fibre est un véritable enjeu économique. En effet, il permettrait a ces systèmes d'être compétitifs au niveau du coût sur le marche des centrales de navigations inertielles actuellement domine par les gyroscopes laser. Cependant, les problèmes de non réciprocités et d'effondrement du signal provoqués par l'utilisation de ce type de fibre n'ont pas été résolus de façon satisfaisante à ce jour. C'est a ce niveau que l'utilisation de la double conjugaison de phase apparaît comme une solution intéressante. L'objectif de ce travail consistait à valider cette solution d'une part en mettant au point un cristal photoréfractif adapte à cette application et d'autre part en insérant un miroir a double conjugaison de phase dans un gyroscope commercial fonctionnant a 850 mn. Dans un premier temps, nous avons donc etudie un nouveau cristal photorefractif : le titanate de barium calcium (bct) dont l'interet repose sur le fait qu'il ne subit pas de transition de phase de 120\ a 98\ c, contrairement au cristal de titanate de baryum dont il est dérivé. Ce cristal, généralement utilise pour la conjugaison de phase en raison de sa bonne efficacité est en effet détruit si sa température devient inférieure a 10\ c. Notre étude a permis de démontrer les bonnes propriétés photorefractives de ce matériau (coefficients electro-optiques élevés, sensibilité proche infrarouge) et de comprendre les différences de comportement par rapport au titanate de baryum. Dans un second temps, nous avons étudié et optimise un miroir a double conjugaison de phase réalisé avec un cristal de titanate de baryum que nous avons ensuite insere dans un gyromètre a fibre. Ainsi, nous avons pu montrer que le gyrometre a double conjugaison de phase permet de mesurer des rotations et n'introduit pas de non-reciprocités supérieures a la précision du montage que nous avons utilise (200 \/h).

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