1000 resultados para CT colonography (virtual colonoscopy)
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The aim was to propose a strategy for finding reasonable compromises between image noise and dose as a function of patient weight. Weighted CT dose index (CTDI(w)) was measured on a multidetector-row CT unit using CTDI test objects of 16, 24 and 32 cm in diameter at 80, 100, 120 and 140 kV. These test objects were then scanned in helical mode using a wide range of tube currents and voltages with a reconstructed slice thickness of 5 mm. For each set of acquisition parameter image noise was measured and the Rose model observer was used to test two strategies for proposing a reasonable compromise between dose and low-contrast detection performance: (1) the use of a unique noise level for all test object diameters, and (2) the use of a unique dose efficacy level defined as the noise reduction per unit dose. Published data were used to define four weight classes and an acquisition protocol was proposed for each class. The protocols have been applied in clinical routine for more than one year. CTDI(vol) values of 6.7, 9.4, 15.9 and 24.5 mGy were proposed for the following weight classes: 2.5-5, 5-15, 15-30 and 30-50 kg with image noise levels in the range of 10-15 HU. The proposed method allows patient dose and image noise to be controlled in such a way that dose reduction does not impair the detection of low-contrast lesions. The proposed values correspond to high- quality images and can be reduced if only high-contrast organs are assessed.
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BACKGROUND AND PURPOSE: Multi-phase postmortem CT angiography (MPMCTA) is increasingly being recognized as a valuable adjunct medicolegal tool to explore the vascular system. Adequate interpretation, however, requires knowledge about the most common technique-related artefacts. The purpose of this study was to identify and index the possible artefacts related to MPMCTA. MATERIAL AND METHODS: An experienced radiologist blinded to all clinical and forensic data retrospectively reviewed 49 MPMCTAs. Each angiographic phase, i.e. arterial, venous and dynamic, was analysed separately to identify phase-specific artefacts based on location and aspect. RESULTS: Incomplete contrast filling of the cerebral venous system was the most commonly encountered artefact, followed by contrast agent layering in the lumen of the thoracic aorta. Enhancement or so-called oedematization of the digestive system mucosa was also frequently observed. CONCLUSION: All MPMCTA artefacts observed and described here are reproducible and easily identifiable. Knowledge about these artefacts is important to avoid misinterpreting them as pathological findings.
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Neste artigo pretendemos relatar uma experiência de apoio à supervisão de estágio e de dinamização de duas disciplinas na licenciatura de Ciências da Educação – Percurso de Desenvolvimento Pessoal e Social na Universidade de Cabo Verde (Uni-CV), com recurso à Moodle. Esta experiência, em curso, enquadra-se num projeto de Investigação-Ação (IA) a decorrer e com o qual se pretende melhorar a prática de orientação/supervisão de estágios pedagógicos no contexto da Uni-CV. Este texto reporta-se a um dos momentos de desenvolvimento do projeto, relativo à caraterização das competências tecnológicas dos estagiários/estudantes, principais destinatários desta ação e das suas expectativas em relação ao trabalho com ambientes virtuais de aprendizagem. Os dados foram recolhidos com recurso a um inquérito por questionário e a partir da sua análise constatamos que os inquiridos têm alguma facilidade de navegação na Web, possuem também competências básicas para o trabalho em ambientes online, assim como vontade experienciar trabalhar em diferentes ambientes de aprendizagem. As principais dificuldades identificadas, prendem-se com a dificuldade de acesso a um computador e à Internet.
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BACKGROUND: The quality of colon cleansing is a major determinant of quality of colonoscopy. To our knowledge, the impact of bowel preparation on the quality of colonoscopy has not been assessed prospectively in a large multicenter study. Therefore, this study assessed the factors that determine colon-cleansing quality and the impact of cleansing quality on the technical performance and diagnostic yield of colonoscopy. METHODS: Twenty-one centers from 11 countries participated in this prospective observational study. Colon-cleansing quality was assessed on a 5-point scale and was categorized on 3 levels. The clinical indication for colonoscopy, diagnoses, and technical parameters related to colonoscopy were recorded. RESULTS: A total of 5832 patients were included in the study (48.7% men, mean age 57.6 [15.9] years). Cleansing quality was lower in elderly patients and in patients in the hospital. Procedures in poorly prepared patients were longer, more difficult, and more often incomplete. The detection of polyps of any size depended on cleansing quality: odds ratio (OR) 1.73: 95% confidence interval (CI)[1.28, 2.36] for intermediate-quality compared with low-quality preparation; and OR 1.46: 95% CI[1.11, 1.93] for high-quality compared with low-quality preparation. For polyps >10 mm in size, corresponding ORs were 1.0 for low-quality cleansing, OR 1.83: 95% CI[1.11, 3.05] for intermediate-quality cleansing, and OR 1.72: 95% CI[1.11, 2.67] for high-quality cleansing. Cancers were not detected less frequently in the case of poor preparation. CONCLUSIONS: Cleansing quality critically determines quality, difficulty, speed, and completeness of colonoscopy, and is lower in hospitalized patients and patients with higher levels of comorbid conditions. The proportion of patients who undergo polypectomy increases with higher cleansing quality, whereas colon cancer detection does not seem to critically depend on the quality of bowel preparation.
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PURPOSE: To investigate the dual-energy CT behavior of cocaine and heroin and of typical adulterants, and to evaluate the elemental composition of pure cocaine and heroin compared with cocaine and heroin in bodypacks. METHODS: Pure heroin and pure synthetic cocaine samples, eight different adulterants, and in each case ten different bodypacks containing cocaine or heroin, were imaged at 80, 100, 120, and 140 kVp in a dual source CT system at two different degrees of compression. Two radiologists, blinded to the samples, measured the attenuation. The dual-energy index (DEI) was calculated. We performed atomic mass spectrometry for the elemental analysis of pure cocaine, pure heroin, and heroin and cocaine in bodypacks, and 140 kVp in a dual-source CT system. RESULTS: Inter- and intra-observer agreement for attenuation measurements was good (r = 0.61-0.72; p < 0.01). The cocaine bodypacks had a positive DEI of 0.029, while the pure drugs and the heroin bodypacks had a negative DEI (-0.051 to -0.027). Levamisole was the only substance which expressed a positive DEI of 0.011, while the remaining adulterants had negative DEIs ranging between -0.015 and -0.215. Atomic mass spectrometry revealed a concentration of tin in the cocaine bodypack that was 67 times higher than in the pure synthetic cocaine sample. CONCLUSIONS: The different DEIs of bodypacks containing cocaine and heroin allow them to be distinguished with dual-energy CT. Although the material properties of pure cocaine, pure heroin, or common drug extenders do not explain the differences in DEI, tin contamination during illicit natural cocaine production may be a possible explanation.
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O presente trabalho tem como tema aprendizagem em ambiente virtual cujos os objectivos principais são, entender o conceito do ambiente virtual de aprendizagem face ao impacto da sociedade de informação e analisar a utilização dos recursos do ambiente virtual no processo ensino-aprendizagem pelos docentes da Universidade Jean Piaget de Cabo Verde. Para o desenvolvimento deste trabalho recorreu-se a pesquisas bibliográficas e a aplicação de questionário. Como resultado da pesquisa surgem alguns indicadores que permitem dizer que docentes estão familiarizados com os recursos tecnológicos. No que concerne a sensibilidade da utilização do ambiente virtual face ao processo ensino-aprendizagem, percebe-se que o os docentes estão sensibilizados dos que o ambiente virtual oferece para o processo de ensino.
Potencialidades do Campus Virtual Global Aplicações práticas da utilização da plataforma de educação
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A utilização do Campus Virtual Global do Instituto Piaget como instrumento obrigatório no processo de aprendizagem. As ferramentas do Campus aproximam docentes e discentes, aumentam a cooperação, proporcionam maior participação dos alunos e propiciam o consequente desenvolvimento de competências. A nova ênfase do trabalho docente deixa para segundo plano o discurso de retórica e a exposição tradicional e centra-se nos alunos; o professor propõe tarefas e actividades contínuas, apoiadas em ferramentas que propiciam o diálogo socrático.
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Die Diagnostik des plötzlichen Herztods durch bildgebende Techniken ist bislang unzureichend evaluiert. Als Validierungsoption für postmortale koronarangiographische Methoden steht der Sektionsbefund zur Verfügung. Sequenziell postmortal durchgeführte alternative angiographische Methoden sind denkbar. Schließlich bietet die ante mortem durchgeführte Koronarangiographie (CA) - ggf. In Verbindung mit der perkutanen transluminalen Koronarangioplastie (PTCA) - weitere Vergleichsmöglichkeiten. Neben deskriptiven sind hier auch potenziell funktionelle Aussagen zum Stenosegrad möglich.
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O trabalho científico realizado no âmbito dos regulamentos dos cursos de graduação para a obtenção de grau de licenciatura na Universidade Jean Piaget de Cabo Verde, pretende analisar a utilização da VPN, mais concretamente na Universidade Jean Piaget de Cabo Verde. Durante a elaboração desse trabalho será feito uma breve introdução sobre redes de computadores, sobre segurança na rede, um enquadramento teórico sobre VPN, bem como a sua contextualização num ambiente organizacional, mostrando as várias vantagens do seu uso, custo e beneficio e por fim o caso prático na Universidade Jean Piaget.
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CMS (Sistema Gestor de Continguts) és una tecnologia en ple auge que permet implantar solucions web d'una manera senzilla, econòmica i amb un fàcil manteniment per part dels usuaris que en fan ús. Aquest projecte és un estudi que pretén analitzar i escollir el millor CMS dirigit a comerç electrònic d'entre el ventall existent actualment al mercat, creant un document que serveixi de referent o guia a qualsevol persona interessada en implantar un sistema d'aquestes característiques. A més, es centrarà a la programació d'un component instal·lable pel CMS escollit que permeti introduir-nos a la creació d'extensions i ens formi en l'àmbit de la programació web. Aquest component el podrem afegir al CMS i permetrà realitzar compres escanejant codis amb el telèfon mòbil.
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Con este TFM se muestra un laboratorio virtual de química a través de diversos experimentos para la preparación de disoluciones en función de sus expresiones de concentración.
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BACKGROUND: "Virtual" autopsy by postmortem computed tomography (PMCT) can replace medical autopsy to a certain extent but has limitations for cardiovascular diseases. These limitations might be overcome by adding multiphase PMCT angiography. OBJECTIVE: To compare virtual autopsy by multiphase PMCT angiography with medical autopsy. DESIGN: Prospective cohort study. (ClinicalTrials.gov: NCT01541995) SETTING: Single-center study at the University Medical Center Hamburg-Eppendorf, Hamburg, Germany, between 1 April 2012 and 31 March 2013. PATIENTS: Hospitalized patients who died unexpectedly or within 48 hours of an event necessitating cardiopulmonary resuscitation. MEASUREMENTS: Diagnoses from clinical records were compared with findings from both types of autopsy. New diagnoses identified by autopsy were classified as major or minor, depending on whether they would have altered clinical management. RESULTS: Of 143 eligible patients, 50 (35%) had virtual and medical autopsy. Virtual autopsy confirmed 93% of all 336 diagnoses identified from antemortem medical records, and medical autopsy confirmed 80%. In addition, virtual and medical autopsy identified 16 new major and 238 new minor diagnoses. Seventy-three of the virtual autopsy diagnoses, including 32 cases of coronary artery stenosis, were identified solely by multiphase PMCT angiography. Of the 114 clinical diagnoses classified as cardiovascular, 110 were confirmed by virtual autopsy and 107 by medical autopsy. In 11 cases, multiphase PMCT angiography showed "unspecific filling defects," which were not reported by medical autopsy. LIMITATION: These results come from a single center with concerted interest and expertise in postmortem imaging; further studies are thus needed for generalization. CONCLUSION: In cases of unexpected death, the addition of multiphase PMCT angiography increases the value of virtual autopsy, making it a feasible alternative for quality control and identification of diagnoses traditionally made by medical autopsy. PRIMARY FUNDING SOURCE: University Medical Center Hamburg-Eppendorf.
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Com o crescimento do mercado de dispositivos móveis e uma previsão de aumento significativo do turismo em São Vicente, este trabalho apresenta a conceção e o desenvolvimento de uma aplicação Android para prover e gerir roteiros turísticos a partir de uma abordagem distribuída com o armazenamento de dados na nuvem com a plataforma virtual. O aumento dos turistas na cidade promoverá o turismo regional e a visitação aos pontos turísticos da cidade do Mindelo. A dificuldade na localização dos pontos turísticos pode ser um problema para os turistas, devido à falta de informações, sinalizações e de serviços para atender a demanda. O uso de aplicações para dispositivos móveis vai ao encontro desta necessidade, permitindo o desenvolvimento de inúmeras aplicações turísticas. Neste contexto, este trabalho apresenta o estudo e o desenvolvimento de uma aplicação para dispositivos móveis, com sistema operativo Android, que serve como a informação virtual da cidade do Mindelo. Por meio da aplicação o turista pode se localizar no mapa, permite buscar rapidamente os pontos turísticos, ver o itinerário da linha do turismo, seus pontos de paragem e obter informações detalhadas de cada ponto turístico. Esta aplicação utiliza sistemas de localização geográfica, mapas, comunicação de dados e base de dados.