91 resultados para radical media


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Purpose: To evaluate the efficacy and toxicity of stereotactic fractionated radiotherapy (SFRT) for patients with pituitary macroadenoma (PMA).Methods and Materials: Between March 2000 and March 2009, 27 patients (male to female ratio, 1.25) with PMA underwent SFRT (median dose, 50.4 Gy). Mean age of the patients was 56.5 years (range, 20.3 - 77.4). In all but one patient, SFRT was administered for salvage treatment after surgical resection (transphenoidal resection in 23, transphenoidal resection followed by craniotomy in 2 and multiple transphenoidal resections in another patient). In 10 (37%) patients, the PMAs were functional (3 ACTH-secreting, 3 prolactinomas, 2 growth hormone-secreting and 2 multiple hormone-secretion). Three (11.1%) and 9 (33.3%) patients had PMA abutting and compressing the optic chiasm, respectively. Mean tumor volume was 2.9 +/- 4.6 cm(3). Eighteen (66.7%) patients had hypopituitarism prior to SFRT. The mean follow-up period after SFRT was 72.4 +/- 37.2 months.Results: Tumor size decreased for 6 (22.2%) patients and remained unchanged for 19 (70.4%) other patients. Two (7.4%) patients had tumor growth inside the prescribed treatment volume. The estimated 5-year tumor growth control was 95.5% after SFRT. Biochemical remission occurred in 3 (30%) patients with functional PMA. Two patients with normal anterior pituitary function before SFRT developed new deficits 25 and 65 months after treatment. The 5-year survival without new anterior pituitary deficit was thus 95.8%. Five patients with visual field defect had improved visual function and 1 patient with no visual defect prior to SFRT, but an optic chiasm abutting tumor, had a decline in visual function. The estimated 5-year vision and pituitary function preservation rates were 93.2% and 95.8%, respectively.Conclusions: SFRT is a safe and effective treatment for patients with PMA, although longer follow-up is needed to evaluate long-term outcomes. In this study, approximately 1 patient with visual field defect out of two had an improved visual.

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n this paper the iterative MSFV method is extended to include the sequential implicit simulation of time dependent problems involving the solution of a system of pressure-saturation equations. To control numerical errors in simulation results, an error estimate, based on the residual of the MSFV approximate pressure field, is introduced. In the initial time steps in simulation iterations are employed until a specified accuracy in pressure is achieved. This initial solution is then used to improve the localization assumption at later time steps. Additional iterations in pressure solution are employed only when the pressure residual becomes larger than a specified threshold value. Efficiency of the strategy and the error control criteria are numerically investigated. This paper also shows that it is possible to derive an a-priori estimate and control based on the allowed pressure-equation residual to guarantee the desired accuracy in saturation calculation.

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The quantity of interest for high-energy photon beam therapy recommended by most dosimetric protocols is the absorbed dose to water. Thus, ionization chambers are calibrated in absorbed dose to water, which is the same quantity as what is calculated by most treatment planning systems (TPS). However, when measurements are performed in a low-density medium, the presence of the ionization chamber generates a perturbation at the level of the secondary particle range. Therefore, the measured quantity is close to the absorbed dose to a volume of water equivalent to the chamber volume. This quantity is not equivalent to the dose calculated by a TPS, which is the absorbed dose to an infinitesimally small volume of water. This phenomenon can lead to an overestimation of the absorbed dose measured with an ionization chamber of up to 40% in extreme cases. In this paper, we propose a method to calculate correction factors based on the Monte Carlo simulations. These correction factors are obtained by the ratio of the absorbed dose to water in a low-density medium □D(w,Q,V1)(low) averaged over a scoring volume V₁ for a geometry where V₁ is filled with the low-density medium and the absorbed dose to water □D(w,QV2)(low) averaged over a volume V₂ for a geometry where V₂ is filled with water. In the Monte Carlo simulations, □D(w,QV2)(low) is obtained by replacing the volume of the ionization chamber by an equivalent volume of water, according to the definition of the absorbed dose to water. The method is validated in two different configurations which allowed us to study the behavior of this correction factor as a function of depth in phantom, photon beam energy, phantom density and field size.

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QUESTIONS UNDER STUDY: To investigate if two distinct, commercially available embryo culture media have a different effect on birthweight and length of singleton term infants conceived after IVF-ICSI. METHODS: University hospital based cohort study. Between 1 January 2000 and 31 December 2004, patients conceiving through IVF-ICSI at the University Hospital, Lausanne have been allocated to two distinct embryo culture media. Only term singleton pregnancies were analysed (n = 525). Data analysis was performed according to two commercially available culture media: Vitrolife (n = 352) versus Cook (n = 173). Analysis was performed through linear regression adjusted for confounders. Media were considered equivalent if the 95% confidence interval lay between -150 g/+150 g. RESULTS: Length, gestational age and distribution of birthweight percentiles did not differ between groups (for both genders). Analysis of the whole cohort, adjusted for a subset of confounders, resulted in a statistically not different mean birthweight between the two groups (Vitrolife +37 g vs Cook, 95%CI: -46 g to 119 g) suggesting equivalence. Adjustment for an enlarged number of confounders in a subsample of patients (n = 258) also revealed no relevant mean birthweight difference of +71 g (95%CI: -45 g to 187 g) in favour of Vitrolife; however, lacking power to prove equivalence. CONCLUSIONS: Our data suggest that significant differences in birthweight due to these two distinct, commercially available embryo culture media are unlikely.

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Previous studies have demonstrated that the extent to which media coverage influences the issue priorities of policy makers is contingent on the type of issue, media, and political agenda. This article contends that the relationship between media and political agendas varies across the phases of the decision-making process. Based on a comprehensive dataset on issue attention in media coverage and various policy-making channels covering the years 1996-2003, the article analyses the level of media coverage and, more importantly, the distribution and correspondence of issue attention between media and political agendas across the four successive phases of the decision-making process (initiation, preparatory, parliamentary, and referendum phases) in Switzerland. Despite inversely distributed levels of attention for successive decision-making phases, both media and political agendas are concentrated on fewer issues in the initiation and referendum phases, and they are more strongly correlated in the most decisive stages of the process, that is, the preparatory and referendum phases.

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Résumé Le travail poursuit un triple objectif: A) présenter la place qu'occupe la géographie physique et la géographie urbaine dans un corpus de cinq récits de voyages castillans de la fin du Moyen-Age, en se centrant particulièrement sur le relief, les eaux continentales, les mers, les côtes, le climat, la végétation, la faune et les villes; B) analyser les ressources discursives dont se servent les rédacteurs pour transmettre ces contenus; C) et réunir le lexique géographique des textes, en l'organisant autour des thématiques mentionnées, en définissant les mots et en faisant ressortir leur valeur dans le contexte discursif. L'étude est introduite par une analyse de la situation communicative dans laquelle se forgent les récits du corpus: contexte historique, social, culturel et textuel, d'une part; identité des voyageurs- rédacteurs, identité des destinataires, et objectifs divers aussi bien des voyages que de leur mise en écriture, d'autre part. De cette analyse ressortent quelques intentions et préoccupations communes aux voyageurs-rédacteurs qui pourraient se résumer en: A) une conscience de la difficulté du voyage; B) une conscience de réaliser un mouvement vers un monde éloigné et étrange; C) une volonté de transmettre des connaissances sur le monde; D) un désir de présenter ce qu'ils racontent comme le fruit d'une expérience vécue et de le faire avec véracité. L'analyse introductoire montre également que cette approche du voyage et la conception du récit qui en découle déterminent le choix de certains contenus géographiques et une façon précise d'exposer l'expérience du voyage: les textes transmettent des connaissances sur le monde et construisent un discours informatif sur l'espace, tout en décrivant un univers étrange et en insistant sur leur caractère testimonial. Le corps du travail est articulé en trois parties. Le premier volet permet de faire émerger la place réservée à la géographie, surtout physique, dans les récits. Il dévoile l'intérêt naissant manifesté par les voyageurs-rédacteurs pour la géographie physique et témoigne de la typologie diversifiée des descriptions urbaines. Il éclaire également le rapport intime liant les thématiques privilégiées dans les textes, les intérêts des rédacteurs et de leur public, et les objectifs de chaque récit. La géographie transmise est non-livresque, issue de l'expérience et, par conséquent, partielle. Le deuxième volet montre le fonctionnement d'une description qui est porteuse d'informations sur l'espace et qui véhicule des savoirs sur le monde, en particulier sur le monde inconnu. Les opérations de nommer, mesurer et adjectiver l'espace parcouru, en le comparant ensuite à l'espace connu sont analysées en détail. Cette partie du travail met en exergue les connaissances, les croyances et les valeurs partagées entre rédacteurs et récepteurs sur lesquelles se construit un discours destiné à transmettre de nouveaux savoirs sur le monde. Les textes se présentent, en outre, comme un témoignage basé sur l'expérience des voyageurs: l'importance de l'information acquise par l'ouïe porte les rédacteurs à incorporer dans leurs récits de nombreuses voix qui racontent le monde et fait du discours géographique un discours clairement polyphonique. Enfin, le troisième volet réunit pour la première fois le lexique géographique castillan en usage à la fin du Moyen-Âge. Procédant de textes rédigés par des non spécialistes, il nous permet d'évaluer les connaissances géographiques d'un homme de l'époque et inclut définitions, exemples d'usage des mots en contexte, données étymologiques, diachroniques, morphosyntaxiques, sémantiques et encyclopédiques. Dans son ensemble, la thèse témoigne de l'intérêt d'une approche des récits de voyage par le triple axe thématique, discursif et lexical.

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BACKGROUND: Fatalities following contrast medium exposure are extremely rare in clinical routine, though they may occur as an exception. Some may fall under the purview of the inquiring authorities and forensic pathologists due to their in-hospital occurrence. The purpose of this study was to assess the risk factors for anaphylaxis due to contrast medium administration that can be identified in fatal cases. METHODS: Fatalities occurred during the course of clinical investigations with contrast media described in the literature and fatal reactions to contrast agents that had undergone forensic investigations in our medicolegal center were reviewed with respect to patient characteristics, administered contrast medium, performed biochemical investigations and potential risk factors identified based on clinical history and medical records. RESULTS: Biochemical investigations into the fatal cases examined in our facility revealed increased mast cell tryptase, total IgE and activated mast cells in all subjects. Data obtained from the literature and our own investigations indicated that in only a minority of the fatal cases had there been previous exposure to contrast compounds, while most cases of severe anaphylaxis involved patients who apparently reacted on initial exposure. CONCLUSIONS: Most fatal cases failed to present any identifiable predisposing conditions out of those traditionally considered as risk factors for an anaphylactic reaction to contrast compounds in the medical histories of the patients. Comprehensive clinical histories and thorough reviews of medical data, along with exhaustive forensic investigations, provide information that is relevant in order to better appreciate the interwoven relationships linking all factors potentially involved in the pathogenesis of fatal anaphylaxis to contrast media. © 2014 S. Karger AG, Basel.

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AIMS: Common carotid artery intima-media thickness (CCIMT) is widely used as a surrogate marker of atherosclerosis, given its predictive association with cardiovascular disease (CVD). The interpretation of CCIMT values has been hampered by the absence of reference values, however. We therefore aimed to establish reference intervals of CCIMT, obtained using the probably most accurate method at present (i.e. echotracking), to help interpretation of these measures. METHODS AND RESULTS: We combined CCIMT data obtained by echotracking on 24 871 individuals (53% men; age range 15-101 years) from 24 research centres worldwide. Individuals without CVD, cardiovascular risk factors (CV-RFs), and BP-, lipid-, and/or glucose-lowering medication constituted a healthy sub-population (n = 4234) used to establish sex-specific equations for percentiles of CCIMT across age. With these equations, we generated CCIMT Z-scores in different reference sub-populations, thereby allowing for a standardized comparison between observed and predicted ('normal') values from individuals of the same age and sex. In the sub-population without CVD and treatment (n = 14 609), and in men and women, respectively, CCIMT Z-scores were independently associated with systolic blood pressure [standardized βs 0.19 (95% CI: 0.16-0.22) and 0.18 (0.15-0.21)], smoking [0.25 (0.19-0.31) and 0.11 (0.04-0.18)], diabetes [0.19 (0.05-0.33) and 0.19 (0.02-0.36)], total-to-HDL cholesterol ratio [0.07 (0.04-0.10) and 0.05 (0.02-0.09)], and body mass index [0.14 (0.12-0.17) and 0.07 (0.04-0.10)]. CONCLUSION: We estimated age- and sex-specific percentiles of CCIMT in a healthy population and assessed the association of CV-RFs with CCIMT Z-scores, which enables comparison of IMT values for (patient) groups with different cardiovascular risk profiles, helping interpretation of such measures obtained both in research and clinical settings.

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It is commonly found that young people tend to adopt the political party choice of their parents. However, far less is known about the applicability of this theory when investigating radical right support. Using the Swiss Household panel data (1999e2007), this study empirically identifies the relationship between parents' preference for the Swiss radical right party SVP and their attitudes toward immigrants and the EU, and their offspring's preference for the SVP. Disaggregating fathers' and mothers' influence reveals that in particular, mothers' SVP support plays a role in SVP support among young people, even after controlling for educational similarities. We also demonstrate that girls are more likely to be influenced by their mothers than are boys. Furthermore, parents' negative attitudes toward the EU exert a positive influence on their children's radical right voting, independent of their voting pattern.