• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 276
  • 199
  • 29
  • 19
  • 11
  • 11
  • 9
  • 9
  • 8
  • 8
  • 6
  • 5
  • 3
  • 3
  • 2
  • Tagged with
  • 682
  • 218
  • 205
  • 182
  • 80
  • 65
  • 44
  • 43
  • 42
  • 42
  • 40
  • 38
  • 34
  • 34
  • 34
  • 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.
641

Biofeedback EMG ou eletroestimulação transcutânea parassacral em crianças com disfunção do trato urinário inferior: estudo prospectivo e randomizado / EMG Biofeedback or parasacral transcutaneous eletrical nerve stimulation in children with lower urinary tract dysfunction: study prospective randomized

Joceara Neves dos Reis 30 November 2015 (has links)
INTRODUÇÃO: A disfunção do trato urinário inferior (DTUI) pode decorrer de contrações vesicais durante a fase de enchimento (hiperatividade do detrusor) ou a falta de coordenação entre a contração vesical e o relaxamento dos músculos do assoalho pélvico durante o esvaziamento vesical (disfunção miccional). Várias publicações sugerem benefícios do uso de biofeedback eletromiográfico (EMG) e eletroestimulação transcutânea parassacral (ENTP) no tratamento destas condições. Contudo faltam estudos controlados comparando estas duas formas de tratamento. OBJETIVO: Comparar a eficácia das técnicas de biofeedback EMG e ENTP em crianças com DTUI. MÉTODOS: Estudo prospectivo e randomizado com 64 crianças, sendo 43 meninas e 21 meninos com idade média 9,39 anos. As crianças foram divididas em dois grupos de tratamento: grupo biofeedback (GB) e grupo de ENTP (GE). Os critérios para avaliar a eficácia do tratamento foram a taxa de resolução dos sintomas noturnos e diurnos, comprovados por diário miccional, urofluxometria, questionários (DVSS - Dysfunction voiding symptoms score), avaliação da qualidade de vida (QV), melhora da constipação e do número de episódios de infecção do trato urinário (ITU).RESULTADOS: No GB 54,9% das crianças tiveram resposta completa e no GE 60,6% em relação a melhora diurna (p=0,483) e 29,6% e 25% em relação a melhora noturna respectivamente (p=0,461). Em relação ao diário miccional, urofluxometria e DVSS, ambos os grupos tiveram melhora estatisticamente significante (p=0,001), porém a QV não teve diferença entre os grupos (p=0,959 e p=0,065). Na avaliação da constipação, houve decréscimo no GB de 61,3% para 19,4% (p=0,002) e no GE de 33,3% para 6,2% (p=0,013). Nenhuma criança apresentou ITU após o término do tratamento (p < 001). CONCLUSÃO: O biofeedback EMG e a ENTP são efetivos para o tratamento de DTUI.Esta eficácia se traduz por melhora dos sintomas diurnos e noturnos bem como na avaliação feita por questionário e urofluxometria. Ambas as técnicas se mostrarm eficazes, embora o biofeedback tenha requerido um menor número de sessões / INTRODUCTION: The lower urinary tract dysfunction (LUTD) may be due to bladder contractions during the filling phase (detrusor overactivity) or the lack of coordination between bladder contraction and relaxation of the pelvic floor muscles during bladder emptying (voiding dysfunction ). Several publications have suggested benefits of using electromyographic biofeedback (EMG) and parasacral transcutaneous electrical nerve stimulation (TENS) in treating these conditions. However there is a lack of controlled studies comparing these two forms of treatment. OBJECTIVE: To compare the effectiveness of EMG biofeedback and parasacral TENS techniques in children with DTUI. METHODS: A prospective and randomized study with 64 children, 43 girls and 21 boys, mean age 9.39 years. The children were divided into two treatment groups: biofeedback group and parasacral TENS. The criteria for assessing the effectiveness of techniques were the rate of resolution of daytime and nighttime symptoms, improvements in voiding diary, uroflowmetry and questionnaires. (DVSS - Dysfunction voiding symptoms score). We also acessed changes in quality of life (QOL) constipation and number of episodes of lower urinary tract infection (UTI). RESULTS: GB 54.9% of children had complete response in EMG biofeedback group and 60.6% in those treated by parasacral TENS in daytime symptoms (p = 0.483) and 29.6% and 25% in night time respectively (p = 0.461). Regarding the voiding diary, uroflowmetry and DVSS, both groups had statistically significant improvement (p = 0.001), but the QOL showed no difference between groups (p = 0.959 and p = 0.065). In the evaluation of constipation, there was a decrease in EMG biofeedback group 61.3% to 19.4% (p = 0.002) and in parasacral TENS group 33.3% to 6.2% (p = 0.013). No child had UTI after the end of treatment (p <.001). CONCLUSION: EMG biofeedback and the parasacral TENS are effective for treating DTUI. This efficiency translates into improved daytime and nighttime symptoms as well as in the evaluation made by questionnaire and uroflowmetry. Both techniques showed excellent results, although biofeedback required a fewer number of sessions
642

Systematic evaluation of oligodeoxynucleotide binding and hybridization to modified multi-walled carbon nanotubes

Kaufmann, Anika, Hampel, Silke, Rieger, Christiane, Kunhardt, David, Schendel, Darja, Füssel, Susanne, Schwenzer, Bernd, Erdmann, Kati 09 November 2017 (has links) (PDF)
Background: In addition to conventional chemotherapeutics, nucleic acid-based therapeutics like antisense oligodeoxynucleotides (AS-ODN) represent a novel approach for the treatment of bladder cancer (BCa). An efcient delivery of AS-ODN to the urothelium and then into cancer cells might be achieved by the local application of multiwalled carbon nanotubes (MWCNT). In the present study, pristine MWCNT and MWCNT functionalized with hydrophilic moieties were synthesized and then investigated regarding their physicochemical characteristics, dispersibility, biocompatibility, cellular uptake and mucoadhesive properties. Finally, their binding capacity for AS-ODN via hybridization to carrier strand oligodeoxynucleotides (CS-ODN), which were either non-covalently adsorbed or covalently bound to the diferent MWCNT types, was evaluated. Results: Pristine MWCNT were successfully functionalized with hydrophilic moieties (MWCNT-OH, -COOH, -NH2, -SH), which led to an improved dispersibility and an enhanced dispersion stability. A viability assay revealed that MWCNTOH, MWCNT-NH2 and MWCNT-SH were most biocompatible. All MWCNT were internalized by BCa cells, whereupon the highest uptake was observed for MWCNT-OH with 40% of the cells showing an engulfment. Furthermore, all types of MWCNT could adhere to the urothelium of explanted mouse bladders, but the amount of the covered urothelial area was with 2–7% rather low. As indicated by fuorescence measurements, it was possible to attach CS-ODN by adsorption and covalent binding to functionalized MWCNT. Adsorption of CS-ODN to pristine MWCNT, MWCNT-COOH and MWCNT-NH2 as well as covalent coupling to MWCNT-NH2 and MWCNT-SH resulted in the best binding capacity and stability. Subsequently, therapeutic AS-ODN could be hybridized to and reversibly released from the CS-ODN coupled via both strategies to the functionalized MWCNT. The release of AS-ODN at experimental conditions (80 °C, bufer) was most efective from CS-ODN adsorbed to MWCNT-OH and MWCNT-NH2 as well as from CS-ODN covalently attached to MWCNT-COOH, MWCNT-NH2 and MWCNT-SH. Furthermore, we could exemplarily demonstrate that AS-ODN could be released following hybridization to CS-ODN adsorbed to MWCNT-OH at physiological settings (37 °C, urine). Conclusions: In conclusion, functionalized MWCNT might be used as nanotransporters in antisense therapy for the local treatment of BCa.
643

Assessing the effects of water exchange on quantitative dynamic contrast enhanced MRI

Bains, Lauren Jean January 2011 (has links)
Applying mathematical models to dynamic contrast enhanced MRI (DCE MRI) data to perform quantitative tracer kinetic analysis enables the estimation of tissue characteristics such as vascular permeability and the fractional volume of plasma in a tissue. However, it is unclear to what extent modeling assumptions, particularly regarding water exchange between tissue compartments, impacts parameter estimates derived from clinical DCE MRI data. In this work, a new model is developed which includes water exchange effects, termed the water exchange modified two compartment exchange model (WX-2CXM). Two boundaries of this model (the fast and no exchange limits) were used to analyse a clinical DCE MRI bladder cancer dataset. Comparisons with DCE CT, which is not affected by water exchange, suggested that water exchange may have affected estimates of vp, the fractional volume of plasma. Further investigation and simulations led to the development of a DCE MRI protocol which was sensitised to water exchange, in order to further evaluate the water exchange effects found in the bladder cancer dataset. This protocol was tested by imaging the parotid glands in eight healthy volunteers, and confirmed evidence of water exchange effects on vp, as well as flow Fp and the fractional volume of extravascular extracellular space ve. This protocol also enabled preliminary estimates of the water residence times in parotid tissue, however, these estimates had a large variability and require further validation. The work presented in this thesis suggests that, although water exchange effects do not have a large effect on clinical data, the effect is measurable, and may lead to the ability to estimate of tissue water residence times. Results do not support a change in the current practise of neglecting water exchange effects in clinical DCEMRI acquisitions.
644

Caracterização de agregados supramoleculares: interação de vesículas de Doda com polimetacrilato (OU) Caracterização de agregados supramoleculares: interação de vesículas de dioctadecildimetilamônio com polimetacrilato / Characterisation of supramolecular aggregates: interaction of dioctadecyldimethylammonium vesicles with polymethacrylate

Idélcio Nogueira da Silva 15 April 2002 (has links)
Este trabalho teve como objetivo estudar a interação de polimetacrilato com vesículas de metacrilato de dioctadecildimetílamônio (DODAM) e brometo de dioctadecildimetilamônio (DODAB). A fotoirradiação de vesículas de DODAM a formou polimetacrilato na superfície vesicular do polímero, através da polimerização do contra-íon. Vesículas polimerizadas foram mais estáveis frenta á adição de metanol do que vesículas não polimerizadas. A estabilização da bicamada vesicular foi confirmada com o aumento da retenção da carboxifluoresceína (CF). Vesículas injetadas de DODAM retiveram cerca de 25% de CF, enquanto que vesículas polimerizadas retiveram cerca de 75%. Experimentos de temperatura de transição de fase por turbidez e tensão superfícial mostraram que o polimetacrilato formado na superfície vesicular diminui a temperatura de transição de fase e reduz a cooperatividade. A interação de fosfatase alcalina (Fal) com vesículas de DODAM e colinametacrilato de dicetilfosfato (DCM) foi estudada, como um primeiro passo para a construção de um micro-reator. Foi observada a precipitação na presença de DODAM, mas não em presença de DCM. Isto pode ser explicado pela forte interação entre a superfície de vesículas de dioctadecildimetilamônio (bicamada com carga negativa) com a fosfatase alcalina (carga negativa). Esta precipitação não foi observada com vesículas de DCM (bicamada negativa). Experimentos de monocamada confirmaram estes resultados. DCM e DODAM formaram monocamadas mistas estáveis, sugerindo que vesículas mistas poderiam ser usadas para superar as interações eletrostáticas fortes entre os surfactantes e a enzima. / This work had as objective studying the interaction of polymethacrylate with dioctadecyldimethylammonium methacrylate (DODAM) and brornide (DODAB). The fotoirradiation of vesicular suspensions of DODAM formed polymethacrylate on the vesicle surface though counter-ion polymerization. Polymerized vesicles were more stables on methanol addition than non-polymerized vesicles. Bilayer stability was confirmed with the retention of carboxyfluorescein (CF). DODAM injected vesicles without polymerization retained about 25% of CF, while polymerized DODAM retained about 75%. Experiments of phase transition temperature by turbidity and surface tension showed that polymethacrylate formed at vesicle surface drops phase transition temperature and reduces cooperativity. Polymethacrylic acid and polymethacrylic acid containing rodhamine B covalently linked was used to monitor polymer-vesicle interaction. Experiments showed that the polymer interacts electrostatically with the DODAB bilayer, causing precipitation and or aggregation. The polymer, initially on a confonnation with many hipercoiled hydrophobic regions, opens as interacts with DODAB vesicles. The interaction of alkaline phosphatase (Fal) with vesicles of DODAM and colina-methacrylate dicetylphosphate (DCM) was studied, as a preliminary step for a micro-reactor construction. Precipitation was observed in presence of DODAM, but not in presence of DCM. This may be explained by the strong interaction between the surface of dioctadecyldimethy lammonium vesicles (positive charged bylayer) with Fal (negative charge). This precipitation was not observed with DCM vesicles (negative charged bilayer). Monolayer experiments confirm these results. Experiments showed that DCM and DODAM form stabled mixed monolayers. Suggesting that mixed vesicles could be tried to overcome strong electrostatic interactions between surfactants and enzyme.
645

Systematic evaluation of oligodeoxynucleotide binding and hybridization to modified multi-walled carbon nanotubes

Kaufmann, Anika, Hampel, Silke, Rieger, Christiane, Kunhardt, David, Schendel, Darja, Füssel, Susanne, Schwenzer, Bernd, Erdmann, Kati 09 November 2017 (has links)
Background: In addition to conventional chemotherapeutics, nucleic acid-based therapeutics like antisense oligodeoxynucleotides (AS-ODN) represent a novel approach for the treatment of bladder cancer (BCa). An efcient delivery of AS-ODN to the urothelium and then into cancer cells might be achieved by the local application of multiwalled carbon nanotubes (MWCNT). In the present study, pristine MWCNT and MWCNT functionalized with hydrophilic moieties were synthesized and then investigated regarding their physicochemical characteristics, dispersibility, biocompatibility, cellular uptake and mucoadhesive properties. Finally, their binding capacity for AS-ODN via hybridization to carrier strand oligodeoxynucleotides (CS-ODN), which were either non-covalently adsorbed or covalently bound to the diferent MWCNT types, was evaluated. Results: Pristine MWCNT were successfully functionalized with hydrophilic moieties (MWCNT-OH, -COOH, -NH2, -SH), which led to an improved dispersibility and an enhanced dispersion stability. A viability assay revealed that MWCNTOH, MWCNT-NH2 and MWCNT-SH were most biocompatible. All MWCNT were internalized by BCa cells, whereupon the highest uptake was observed for MWCNT-OH with 40% of the cells showing an engulfment. Furthermore, all types of MWCNT could adhere to the urothelium of explanted mouse bladders, but the amount of the covered urothelial area was with 2–7% rather low. As indicated by fuorescence measurements, it was possible to attach CS-ODN by adsorption and covalent binding to functionalized MWCNT. Adsorption of CS-ODN to pristine MWCNT, MWCNT-COOH and MWCNT-NH2 as well as covalent coupling to MWCNT-NH2 and MWCNT-SH resulted in the best binding capacity and stability. Subsequently, therapeutic AS-ODN could be hybridized to and reversibly released from the CS-ODN coupled via both strategies to the functionalized MWCNT. The release of AS-ODN at experimental conditions (80 °C, bufer) was most efective from CS-ODN adsorbed to MWCNT-OH and MWCNT-NH2 as well as from CS-ODN covalently attached to MWCNT-COOH, MWCNT-NH2 and MWCNT-SH. Furthermore, we could exemplarily demonstrate that AS-ODN could be released following hybridization to CS-ODN adsorbed to MWCNT-OH at physiological settings (37 °C, urine). Conclusions: In conclusion, functionalized MWCNT might be used as nanotransporters in antisense therapy for the local treatment of BCa.
646

Leiomyosarcoma of the Urinary Bladder in Adult Patients: A Systematic Review of the Literature and Meta-Analysis

Zieschang, Helen, Koch, Rainer, Wirth, Manfred P., Froehner, Michael 06 August 2020 (has links)
Purpose: Leiomyosarcoma of the urinary bladder is exceedingly rare. Most clinicians come across only a few cases during their career, and information regarding treatment and outcome is scattered in the scientific literature. Interested clinicians and patients have to undertake troublesome search for treatment and outcome information. Material and methods: We performed a systematic review of the literature using the PubMed and Web of Science databases and included all identified cases published in English language between 1970 and June 2018 into a meta-analysis. Prior to the literature search, key questions were formulated and with the data obtained, answers to these questions should be derived. Results: We analyzed clinical data of 210 cases of urinary bladder leiomyosarcoma revealed by this review and seen in our institution. The mean age of patients was 52 years. The majority (75%) of the tumors was classified as high-grade sarcomas. We found no report of a prior radiation therapy to the pelvic organs, but some authors suggested an association between cyclophosphamide treatment and the development of bladder leiomyosarcoma, especially in patients with retinoblastoma. For the whole sample, we determined 5- and 10-year cancer-specific cumulative mortality rates of 38 and 50%. Patients with high-grade sarcomas had a trend toward a higher mortality compared with lowgrade tumors (p = 0.0280). The most promising treatment option seems to be surgery (radical or partial cystectomy) with negative resection margins, possibly supplemented by chemotherapy or radiation. Conclusion: About half of patients with bladder leiomyosarcoma survived on the long run. Low-grade tumors may have a better outcome with, nevertheless, countable long-term mortality. For better assessment of that rare bladder tumor, its best treatment options, and the influence of neoadjuvant or adjuvant therapies on the outcome of patients, a larger series with longterm survival data is required.
647

Návrh ventilového bloku rekuperačního hydrostatického modulu vozidla / Design of valve block for hydrostatic recuperative module of vehicle

Ranuša, Matúš January 2014 (has links)
The Master`s Thesis deals with design and construction of a valve block for a hydrostatic recuperative module of a vehicle with a direct application on pneu tyred roller AP 240H produced by the AMMANN company. The thesis aims to analyze recovery functions of the valve block in several operating modes of the roller, followed by a selection of the right hydraulic components from the perspective of predefined parameters and pressure differences. Design specifications are based on measurements and mathematical simulations on the experimental stand. The experimental stand for this application has been developed at 1:4 scale as compared to a real vehicle. The thesis includes also design of the supporting console for the module on the frame of the vehicle. The Master`s Thesis is a part of project EUREKA with cooperation Bosch Rexroth.
648

NANOPLASMONIC EFFICACY OF GOLD TRIANGULAR NANOPRISMS IN MEASUREMENT SCIENCE: APPLICATIONS RANGING FROM BIOMEDICAL TO FORENSIC SCIENCES

Thakshila Liyanage (8098115) 11 December 2019 (has links)
<p>Noble metal nanostructures display collective oscillation of the surface conduction electrons upon light irradiation as a form of localized surface plasmon resonance (LSPR) properties. Size, shape and the refractive index of surrounding environment are the key features that controls the LSPR properties. Surface passivating ligands have the ability to modify the charge density of nanostructures to allow resonant wavelength to match that of the incident light, a phenomenon called “plasmoelectric effect,”. According to the drude model Red and blue shifts of LSPR peak of nanostructures are observed in the event of reducing and increasing charge density, respectively. However, herein we report unusual LSPR properties of gold triangular nanoprisms (Au TNPs) upon functionalization with para-substituted thiophenols (X-Ph-SH, X = -NH<sub>2</sub>, -OCH<sub>3</sub>, -CH<sub>3</sub>, -H, -Cl, -CF<sub>3</sub>, and -NO<sub>2</sub>). Accordingly, we hypothesized that an appropriate energy level alignment between the Au Fermi energy and the HOMO or LUMO of ligands allows delocalization of surface plasmon excitation at the hybrid inorganic-organic interface, and thus provides a thermodynamically driven plasmoelectric effect. We further validated our hypothesis by calculating the HOMO and LUMO levels and also work function changes of Au TNPs upon functionalization with para substituted thiol. We further utilized our unique finding to design ultrasensitive plasmonic substrate for biosensing of cancer microRNA in bladder cancer and owe to unpresidential sensitivity of the developed Au TNPs based LSPR sensor, for the first time we have been utilized to analysis the tumor suppressor microRNA for more accurate diagnosis of BC. Additionally, we have been advancing our sensing platform to mitigate the false positive and negative responses of the sensing platform using surface enhanced fluorescence technique. This noninvasive, highly sensitive, highly specific, also does not have false positives technique provide strong key to detect cancer at very early stage, hence increase the cancer survival rate. Moreover, the electromagnetic field enhancement of Surface-Enhanced Raman Scattering (SERS) and other related surface-enhanced spectroscopic processes resulted from the LSPR property. This dissertation describes the design and development of entirely new SERS nanosensors using flexible SERS substrate based on unique LSPR property of Au TNPs and developed sensors shows excellent SERS activity (enhancement factor = ~6.0 x 106) and limit of detection (as low as 56 parts-per-quadrillions) with high selectivity by chemometric analyses among three commonly used explosives (TNT, RDX, and PETN). Further we achieved the programable self-assembly of Au TNPs using molecular tailoring to form a 3D supper lattice array based on the substrate effect. Here we achieved the highest reported sensitivity for potent drug analysis, including opioids and synthetic cannabinoids from human plasma obtained from the emergency room. This exquisite sensitivity is mainly due to the two reasons, including molecular resonance of the adsorbate molecules and the plasmonic coupling among the nanoparticles. Altogether we are highly optimistic that our research will not only increase the patient survival rate through early detection of cancer but also help to battle the “war against drugs” that together is expected to enhance the quality of human life. </p> <p> </p>
649

Gender and Mortality after Radical Cystectomy: Competing Risk Analysis

Heberling, Ulrike, Koch, Rainer, Hübler, Matthias, Baretton, Gustavo B., Hakenberg, Oliver W., Froehner, Michael, Wirth, Manfred P. 26 May 2020 (has links)
Background: Data on the impact of gender on mortality after radical cystectomy is conflicting. We investigated a large single center sample with long-term follow-up in order to determine the relationship between gender and outcome. Patients and Methods: A total of 1,184 consecutive patients who underwent radical cystectomy for high risk superficial or muscle-invasive urothelial or undifferentiated bladder cancer between 1993 and 2015 were stratified by gender. Demographic data was compared using Mann-Whitney U test, chi-square test, or Fisher exact test. Cox proportional hazard models were used for the analysis of competing risks and logit models were used for the prediction of the receipt of adjuvant cisplatin-based chemotherapy. Results: Female patients were older, healthier, less frequently current smokers and had more extravesical tumors. In the multivariate analyses, female gender was an independent predictor of (lower) non-bladder cancer (competing) mortality (hazards ratio [HR] 0.68, 95% CI 0.49–0.95, p = 0.0248) but no predictor of bladder cancer-specific mortality (HR in the full model 1.20, 95% CI 0.94–1.54, p = 0.15). Gender was no predictor of the receipt of adjuvant cisplatin-based chemotherapy. Conclusions: Female gender was associated with an increased risk of extravesical disease but was no independent predictor of bladder cancer-specific mortality. Anatomical differences might be a plausible explanation for these observations.
650

Experimentální ověření in silico predikovaného vazebného proteinu k transkripčnímu faktoru FOXO4 a analýza transkriptomu nádorů močového měchýře / Experimental verification of in silico predicted protein binder to FOXO4 transcription factor and transcriptome analysis of bladder cancer

Tauš, Petr January 2017 (has links)
This diploma thesis includes an experimental and a bioinformatic part. The two parts are linked together through the subject of transcription factors of 'forkhead box O' (FOXO) family. FOXO transcription factors have a key role in many cellular processes including cell cycle regulation, apoptosis and metabolism. For a long time, they have been considered strictly as the tumor-suppressors yet a growing number of evidence is pointing out to their pro-tumorigenic role. In consequence FOXO transcription factors are studied intensively as potential therapeutic targets in cancer. In the past decade, in silico prediction of protein-protein interactions has become popular in basic research as well as in drug development. Nonetheless, the predicted structures are still far from fitting to the expected behavior of the respective biomolecules. In the experimental part of this thesis, I verified the interaction of four in silico predicted protein binders based on naturally occurring PDZ domain with FOXO4 using microscale thermophoresis. Non-invasive bladder tumors represent a heterogeneous disease where reliable prediction of tumor aggressiveness is still lacking despite an intensive research. In the bioinformatic part of this thesis, I described the cellular composition of the tumor microenvironment and demonstrated...

Page generated in 0.0387 seconds