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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.
71

Síndrome do túnel do carpo em idosos: normatização de parâmetros eletrofisiológicos.

Naves, Thiago Guimarães 20 October 2009 (has links)
Made available in DSpace on 2016-01-26T12:51:22Z (GMT). No. of bitstreams: 1 thiagoguimaraesnaves -dissert.pdf: 396666 bytes, checksum: 322f0d9f8506ec60598fc70d1e33cc6a (MD5) Previous issue date: 2009-10-20 / Objective: To establish electrophysiologic values for CTS diagnosis in the elderly. Casuistic and methods: thirty healthy volunteers with at least 65 years old were selected. Exclusion criteria were: any sensory symptom, peripheral neuropathy, sistemic diseases, alcohol abuse and wrist fracture. The following parameters were calculated: 1. Median sensory distal latency on the segment wrist - digit II, 14 cm (SDL); 2. Median/radial latency difference on the segment wrist - digit I, 10 cm (MRD); 3. Median/ulnar latency difference on the segment wrist - digit IV, 14 cm (MUD4); 4. Median/ulnar mixed latency difference on the segment palm - wrist, 8 cm (MUPD); 5. Combined sensory index (CSI), calculated as the adding of MRD, MUD4 and MUPD; 6. Mixed median palmar latency (PL), 8 cm; 7. Median/ulnar motor latency difference, lumbrical/interossei, 8 cm (LUMB); 8. Median motor distal latency, pulse-APB, 8 cm (DML). Results: Twenty-one volunteers were female and 9 were male. Mean age was 69.9 (range 65-86). The 97.5th upper normal limits suggested were: SDL 3.80 ms, MRD 0.95 ms, MUD4 0.95 ms, MUPD 0.50 ms, PL 2.45 ms, CSI 2.20 ms and DML 4.30 ms. Conclusions: The reference values for MRD, MUD4, MUDP and CSI in elderly are different from youngers. There are quite less differences for DSL and PL and none at all for DML. The use of these new values in elderly will reduce the number of false positives. / Objetivo: determinar parâmetros eletrofisiológicos para diagnóstico da STC em idosos. Casuística e Métodos: Trinta voluntários saudáveis com no mínimo 65 anos de idade foram selecionados. Os critérios de exclusão foram: quaisquer sintomas sensitivos, neuropatia periférica, doenças sistêmicas, abuso alcoólico e antecedente de fratura no pulso. Os seguintes parâmetros foram estudados: 1. Latência distal sensitiva do nervo mediano, segmento pulso-dedo II, 14 cm (LDS); 2. Diferença de latência sensitiva mediano/radial, pulso-dedo I, 10 cm (DMR); 3. Diferença de latência sensitiva mediano/ulnar, pulso-IV dedo, 14 cm (DMU4) ; 4. Diferença de latência mista mediano/ulnar, palma-pulso, 8 cm (DMUP); 5. Índice sensitivo combinado (ISC), calculado pela soma de DMR, DMU4 e DMUP; 6. Latência palmar mista do nervo mediano, 8cm (LP); 7. Diferença de latência motora mediano/ulnar lumbrical-interósseo, 8 cm (LUMB); 8. Latência distal motora do nervo mediano, pulso-APB, 8 cm (LDM). Resultados: Vinte e um voluntários eram mulheres e 9 homens com média de idade de 69,9 anos (variação 65-86). Os limites superiores de normalidade 97,5% sugeridos foram: LDS 3,80 ms, DMR 0,95 ms, DMU4 0,95 ms, DMUP 0,50 ms, LP 2,45 ms, ISC 2,20 ms e LDM 4,30 ms. Conclusões: Os valores de referência para DMR, DMU4, DMUP e ISC em idosos são diferentes em relação aos jovens. As diferenças foram menores para LDS e LP; não houve diferença para LDM. O uso destes novos valores reduzirá o número de exames falso-positivos em idosos.
72

Sensory neuronal protection & improving regeneration after peripheral nerve injury

McKay Hart, Andrew January 2003 (has links)
Peripheral nerve trauma is a common cause of considerable functional morbidity, and healthcare expenditure. Particularly in the ~15% of injuries unsuitable for primary repair, standard clinical management results in inadequate sensory restitution in the majority of cases, despite the rigorous application of complex microsurgical techniques. This can largely be explained by the failure of surgical management to adequately address the neurobiological hurdles to optimal regeneration. Most significant of these is the extensive sensory neuronal death that follows injury, and which is accompanied by a reduction in the regenerative potential of axotomised neurons, and in the supportive capacity of the Schwann cell population if nerve repair is delayed. The present study aimed to accurately delineate the timecourse of neuronal death, in order to identify a therapeutic window during which clinically applicable neuroprotective strategies might be adopted. It then proceeded to investigate means to increase the regenerative capacity of chronically axotomised neurons, and to augment the Schwann cells’ ability to promote that regenerative effort. Unilateral sciatic nerve transection in the rat was the model used, initially assessing neuronal death within the L4&5 dorsal root ganglia by a combination of morphology, TdT uptake nick-end labelling (TUNEL), and statistically unbiased estimation of neuronal loss using the stereological optical disector technique. Having identified 2 weeks, and 2 months post-axotomy as the most biologically relevant timepoints to study, the effect upon neuronal death of systemic treatment with acetyl-L-carnitine (ALCAR 10, or 50mg/kg/day) or N-acetyl-cysteine (NAC 30, or 150mg/kg/day) was determined. A model of secondary nerve repair was then adopted; either 2 or 4 months after unilateral sciatic nerve division, 1cm gap repairs were performed using either reversed isografts, or poly-3-hydroxybutyrate (PHB) conduits containing an alginate-fibronectin hydrogel. Six weeks later nerve regeneration and the Schwann cell population were quantified by digital image analysis of frozen section immunohistochemistry. Sensory neuronal death begins within 24 hours of injury, but takes 1 week to translate into significant neuronal loss. The rate of neuronal death peaks 2 weeks after injury, and neuronal loss is essentially complete by 2 months post-axotomy. Nerve repair is incompletely neuroprotective, but the earlier it is performed the greater the benefit. Two clinically safe pharmaceutical agents, ALCAR & NAC, were found to virtually eliminate sensory neuronal death after peripheral nerve transection. ALCAR also enhanced nerve regeneration independently of its neuroprotective role. Plain PHB conduits were found to be technically simple to use, and supported some regeneration, but were not adequate in themselves. Leukaemia inhibitory factor enhanced nerve regeneration, though cultured autologous Schwann cells (SC’s) were somewhat more effective. Both were relatively more efficacious after a 4 month delay in nerve repair. The most profuse regeneration was found with recombinant glial growth factor (rhGGF-2) in repairs performed 2 months after axotomy, with results that were arguably better than were obtained with nerve grafts. A similar conclusion can be drawn from the result found using both rhGGF-2 and SC’s in PHB conduits 4 months after axotomy. In summary, these findings reinforce the significance of sensory neuronal death in peripheral nerve trauma, and the possibility of its` limitation by early nerve repair. Two agents for the adjuvant therapy of such injuries were identified, that can virtually eliminate neuronal death, and enhance regeneration. Elements in the creation of a bioartificial nerve conduit to replace, or surpass autologous nerve graft for secondary nerve repair are presented.
73

Návrh ražby a primárního ostění tunelu na stavbě vysokorychlostního železničního spojení / Design of excavation and primary tunnel lining on high-speed railway construction

Dostál, Tomáš January 2020 (has links)
As part of modernization of the Brno-Přerov railway line, is in the section between village Blažovice and town Vyškov desined tunnel composed of two monorail tubes about 640 meters length. Tubes are situated in neogenic clay with an overburden height of 11 meters. This master thesis deals with design suitable tunnel exavation, primary lining with static calculation and geotechnical monitoring.
74

Příprava experimentálního měření aerodynamických charakteristik na zmenšeném modelu automobilu v aerodynamickém tunelu / Wind tunnel experiment of scaled car model preparation

Zedník, Roman January 2020 (has links)
This master thesis focuses on designing of an external six-component balance. This universal concept would provide access of results from different models of wings, aircraft and automobiles with relatively small scales. This work also includes theoretical background needed in aerodynamic testing, analysis of 1D beam element model of scale and explanation of components used in scale. Lastly methods of calibration and measurement in aerodynamic tunnel are described, which can be adopted for this design to achieve the adequate level of accuracy.
75

Návrh vysokorychlostní tratě mezi Brnem a Znojmem / Design of the High Speed Track between Brno and Znojmo

Repko, Michal Unknown Date (has links)
The aim of this diploma thesis is to design a new track route of high speed line from Brno to Znojmo, specifically between the planned terminal of high speed line Unkovice and existing railway station Hrušovany nad Jevišovkou. The track is designed for a maximum speed of 250 km/h. The alignment and profile of the line were designed, including the design of the railway superstructure and track geometry parameters.
76

Návrh zařízení pro měření aerodynamických sil a momentů v aerodynamickém tunelu / Design of device for measurement of aerodynamic forces and moments in wind tunnel

Brožek, Petr January 2014 (has links)
The masters thesis is focused on design of the device for measurement of the aerodynamic forces and moments acting on radiators mounted in the wind tunnel test section. The thesis also includes the analysis of the aerodynamic drag which is produced by radiators and the LabView application software development.
77

Ventilace městské zástavby v závislosti na jejím geometrickém uspořádání / Urban Ventilation Dependence on Geometric Configuration

Kukačka, Libor January 2018 (has links)
Title: Urban Ventilation Dependence on Geometric Configuration Author: RNDr. Ing. Libor Kukačka Department: Department of Atmospheric Physics Supervisor: prof. RNDr. Zbyněk Jaňour, DrSc., Academy of Sciences of the Czech Republic, Institute of Thermomechanics, v. v. i. Abstract: The main goal of the thesis is to investigate the impact of urban geometry on the urban ventilation using wind-tunnel modelling. To measure the pollutant transport, both advective and turbulent, within complex urban geometries with a high temporal resolution a special measurement method was developed. At first, the pollution of a simplified urban area was simulated by a ground-level point source and the ventilation of the intersection with respect to four wind directions was studied. Later, the pollution of other simplified and complex urban areas was simulated by a ground-level line source and the ventilation of three different street canyons with respect to wind direction perpendicular and oblique to their along-canyon axis was investigated. The clear impact of urban complexity and wind direction on street canyon ventilation is demonstrated at lateral and top openings of all investigated canyons and the intersection. Whilst the dominance of the pollutant advection is demonstrated at the eaves of pitched roofs, at the roof ridges...
78

N-Methyl-D-Aspartat-Antagonisten induzierten apoptotische Zelluntergänge im Gehirn junger Ratten

Miksa, Michael 06 April 2004 (has links)
Der wichtigste exzitatorische Neurotransmitter Glutamat spielt eine grosse Rolle in der Gehirnentwicklung, wie neuronale Migration und Synaptogenese. Ob glutamaterge Stimulation für das Überleben entwickelnder Neuronen notwendig ist, war bislang jedoch unbekannt. Um zu untersuchen, ob eine Hemmung von Glutamatrezeptoren im unreifen Gehirn zu Neurodegeneration führt, wurden Ratten im Alter von 1 bis 31 Tagen für 24 Stunden mit dem N-Methyl-D-Aspartat-(NMDA) Glutamatrezeptorantagonisten Dizocilpin (MK801) behandelt. Die Dichte neuronaler Degeneration wurde mikroskopisch in Kupfer-Silber- und TUNEL- gefärbten Hirnschnittpräparaten ermittelt und Unterschiede mittels ANOVA analysiert (Signifikanzniveau p / The predominant excitatory neurotransmitter glutamate plays a major role in certain aspects of neural development. However, whether developing neurons depend on glutamate for survival remains unknown. To investigate if deprivation of glutamate stimulation in the immature mammalian brain causes neuronal cell death (apoptosis), rat pups aged 0 to 30 days were treated for 24 hours with dizocilpine maleate (MK801), an N-methyl-D-aspartate-(NMDA) glutamate receptor antagonist. Density of neural degeneration was evaluated by a stereological dissector method in cupric-silver and TUNEL-stained brain slices. Groups were compared by ANOVA and significance considered at p
79

Modelos de regeneração hepática em animais em crescimento: estudos histológicos, moleculares e avaliação de efeitos de imunossupressores / Experimental models of liver regeneration in growing animals. Histological and molecular studies, and evaluation of the effects of immunosuppressants

Tannuri, Ana Cristina Aoun 14 June 2007 (has links)
INTRODUÇÃO: Transplantes parciais de fígado em crianças têm sido realizados com maior freqüência, enfatizando a importância do estudo da regeneração hepática, bem como dos efeitos de drogas imunossupressoras sobre a mesma. A regeneração do parênquima é o resultado do balanço entre multiplicação celular e apoptose, esta última definida como morte celular programada. Neste processo, estão envolvidas expressões de genes pró-apoptóticos (Bak e Bax) e anti-apoptóticos (Bcl-XL e Bcl-2). Dentre as proteínas relacionadas à proliferação hepatocitária, destaca-se a interleucina-6 (IL-6). Embora o modelo de ressecção de 70% da massa hepática de ratos adultos seja amplamente utilizado para estudos de regeneração, não há trabalhos com animais em crescimento. MÉTODOS: Na presente pesquisa, foi padronizado o modelo de hepatectomia parcial em ratos recém-nascidos e em recém-desmamados: realizou-se ligadura com fio de algodão do pedículo dos lobos esquerdo lateral, esquerdo medial e direito medial, seguida da ressecção do parênquima desses lobos. Os fígados remanescentes foram imediatamente pesados e comparados com os pesos dos fígados de animais controles. Para caracterização dos modelos de regeneração, 40 ratos recém-nascidos e 30 recém-desmamados foram submetidos à hepatectomia descrita e mortos nos dias subseqüentes (1, 2, 3, 4 e 7), e o fígado residual submetido a análises de peso e histologia convencional. A seguir, 36 animais (18 recém-nascidos e 18 recém-desmamados) foram divididos nos seguintes grupos: controle, cirurgia simulada e hepatectomia. Um dia após, utilizando métodos moleculares (técnica do RT-PCR), estudou-se a expressão do gene da IL-6, dos genes pró-apoptóticos e anti-apoptóticos nos fígados desses animais e, por meio de métodos imunoistoquímicos, analisou-se a presença de antígenos relacionados à proliferação celular (PCNA) e apoptose (TUNEL) em lâminas preparadas pela técnica do \"tissue microarray\". Em outros 36 ratos (18 recém-nascidos e 18 recém-desmamados), foram administradas drogas imunossupressoras (metilprednisolona, ciclosporina A ou tacrolimus, separadamente) no ato da hepatectomia, e o parênquima hepático remanescente submetido às mesmas análises moleculares e imunoistoquímicas, um dia após. RESULTADOS: A ressecção do parênquima hepático correspondeu a 70% da massa total do fígado. A mortalidade relacionada à hepatectomia nos animais recém-nascidos e recém-desmamados foi 30% e 0% respectivamente. Na análise histológica observou-se maior quantidade de mitoses em hepatócitos no terceiro dia nos recém-nascidos e no segundo dia nos recém-desmamados, com normalização da arquitetura do parênquima até o 7º dia e recuperação total do peso de ambos. No animal recém-nascido, notou-se intensa esteatose associada ao processo regenerativo. A hepatectomia provocou aumento na expressão do gene da IL-6 no fígado residual e diminuição da expressão dos genes pró-apoptóticos em ambos os modelos, além de aumento do anti-apoptótico Bcl-2 nos animais recém-desmamados. O estudo realizado sobre o efeito das drogas imunossupressoras mostrou resultados diferentes daqueles descritos em animais adultos, não havendo alteração no número de células em proliferação (PCNA positivas) ou apoptose (TUNEL positivas). As drogas não tiveram efeito sobre a expressão do gene da IL-6. Metilprednisolona e tacrolimus ocasionaram aumento da expressão do gene anti-apoptótico Bcl-2 em ambos os modelos; metilprednisolona e ciclosporina provocaram aumento na expressão do gene pró-apoptótico Bak nos ratos recém-nascidos. CONCLUSÕES: os modelos de regeneração hepática em ratos recém-nascidos e recém-desmamados foram exeqüíveis e adequados para a pesquisa; a hepatectomia promoveu estímulo da proliferação de hepatócitos com inibição da apoptose; as drogas imunossupressoras utilizadas não exerceram efeito sobre a proliferação de hepatócitos porém provocaram aumento da expressão de genes relacionados a apoptose. / INTRODUCTION: Partial liver transplantation has been performed in children with increasing frequency, and this emphasizes the importance of the studies of hepatic regeneration and the effects of immunosuppressive drugs on this phenomenon. Liver regeneration is controlled by the balance between cell proliferation and apoptosis (defined as a programmed cell death that results from the expression of pro-apoptotic genes - Bax and Bak - and anti-apoptotic genes - Bcl-2 and Bcl-XL). Among proteins related to hepatocyte proliferation, interleukin-6 is an important one. Although the adult rat model of 70% hepatectomy has been widely utilized for studies of liver regeneration, there are no studies using growing animals. METHODS: In the current paper, two experimental models were created utilizing newborn and weaning rats: using a cotton thread, the vascular hilum and the hepatic vein were ligated and the left lateral, left medial and right medial lobes were resected. The remaining liver was immediately harvested and weighted to be compared to control livers. The animals were sacrificed on days 1, 2, 3, 4, and 7 after the operation, the remnant livers were weighted and harvested for histological examinations. Then, 36 animals (18 newborn and 18 weaning animals) were divided into the following groups: control, sham and hepatectomy. One day after, the expressions of IL-6 gene, pro-apoptotic and anti-apoptotic genes were studied in the remnant livers. Immunohistochemical stainings for cell antigens related to cell proliferation (PCNA) and apoptosis (TUNEL) were also performed utilizing tissue microarray sections. In another group of 36 animals (18 newborn and 18 weaning animals), immunosuppressive drugs were administered just after the hepatectomy (methylprednisolone, cyclosporine A or tacrolimus separately), and the remnant liver submitted to the same molecular and immunohistochemical studies. RESULTS: The resected liver corresponded to 70% of the total liver weight. The mortality rates after hepatectomy were 30% and 0% for newborn and weaning rats, respectively. The histological examinations showed a great number of mitoses of hepatocytes on the third day in newborns and on the second day in weaning rats, and normalization of histological aspects by 7 days after hepatectomy and weight recuperation. In the newborn group liver regeneration was related to an intense steatosis. Hepatectomy promoted an increase in the expression of IL-6 gene of the remnant liver, a decreased expression of pro-apoptotic genes in both models, and an increased expression of anti-apoptotic Bcl-2 gene in weaning rats. The study of the effects of immunosuppressants showed different results from those described in adult animals, with no alterations in the number of cells in proliferation (PCNA positive) and apoptosis (TUNEL positive). Drugs had no effect in expression of IL-6 gene. Methylprednisolone and tacrolimus promoted an increased expression of anti-apoptotic gene Bcl-2. In addition, methylprednisolone and cyclosporine promoted an increase in the expression of the pro-apoptotic gene Bak in newborn rats. CONCLUSIONS: The experimental models were feasible and adequate for the current investigations; hepatectomy stimulated hepatocyte proliferation and inhibited hepatic cells apoptosis; the utilized immunosuppressant drugs did not affect hepatocyte proliferation although an increased expression of apoptosis-related genes was verified.
80

Nové směry provádění hydroizolací dopravních podzemních staveb / New directions for waterproofing of underground transport

Čech, Tomáš January 2019 (has links)
This diploma thesis focuses on the implementation of waterproofing of underground constructions using an LLDPE membrane hinged on anchors. In the future, this method will replace the commonly used waterproofing system in Scandinavia with extruded polyethylene foam. This method of tunnel construction and waterproofing is compared with the NRTM method, often used in Central Europe. The thesis describes the installation of a waterproofing system, especially materials, accessories, welding devices and auxiliary installation equipment. The main focus of the thesis is to verify the reliability of the individual types of welds and to assess the waterproofing system in terms of implementation and environmental demands.

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