940 resultados para Superficial dose
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INTRODUCTION: Interindividual variations in regional structural properties covary across the brain, thus forming networks that change as a result of aging and accompanying neurological conditions. The alterations of superficial white matter (SWM) in Alzheimer's disease (AD) are of special interest, since they follow the AD-specific pattern characterized by the strongest neurodegeneration of the medial temporal lobe and association cortices. METHODS: Here, we present an SWM network analysis in comparison with SWM topography based on the myelin content quantified with magnetization transfer ratio (MTR) for 39 areas in each hemisphere in 15 AD patients and 15 controls. The networks are represented by graphs, in which nodes correspond to the areas, and edges denote statistical associations between them. RESULTS: In both groups, the networks were characterized by asymmetrically distributed edges (predominantly in the left hemisphere). The AD-related differences were also leftward. The edges lost due to AD tended to connect nodes in the temporal lobe to other lobes or nodes within or between the latter lobes. The newly gained edges were mostly confined to the temporal and paralimbic regions, which manifest demyelination of SWM already in mild AD. CONCLUSION: This pattern suggests that the AD pathological process coordinates SWM demyelination in the temporal and paralimbic regions, but not elsewhere. A comparison of the MTR maps with MTR-based networks shows that although, in general, the changes in network architecture in AD recapitulate the topography of (de)myelination, some aspects of structural covariance (including the interhemispheric asymmetry of networks) have no immediate reflection in the myelination pattern.
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BACKGROUND AND PURPOSE: A pregnant woman was referred for post-operative radiotherapy of a malignant schwannoma in the head and neck region. A best-treatment plan was devised in order to minimize the fetal dose. MATERIAL AND METHODS: The fetal dose resulting from radiological examinations was determined according to international protocols, that resulting from radiotherapy was calculated according to Recommendation 36 of the American Association of Physicists in Medicine (AAPM) Task Group. Pre-treatment dosimetry was performed with an anthropomorphic phantom. Several alternative treatment plans were evaluated. The use of a multileaf collimator (MLC) and a virtual wedge (VW) was compared to cerrobend blocks (CB) and physical wedge (PW). In-vivo dosimetry was performed using a vaginal probe containing thermoluminescent dosimeters (TLD). RESULTS: The total fetal dose resulting from diagnostic and radiotherapy procedures was estimated to be 36 mGy. The technique based on MLC and VW was elected for patient treatment. Measurements for this configuration resulted in afetal dose reduction of 82%. The shielding of the patient's abdomen further reduced the fetal dose by 42%. CONCLUSION: The use of VW and MLC for the treatment of a pregnant woman is highly recommended. Each case should be individually studied with pre-treatment and in-vivo dosimetry.
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Describe los volúmenes de plancton, la distribución, composición e indicadores del fitoplancton de superficie el Crucero de Evaluación Hidroacústica de Recursos Pelágicos 9808-09. Los volúmenes de plancton estuvieron en un rango de 0,01 a 23,3 mL/m3; el primero en la estación costera al norte de Pimentel y el otro al frente de Matarani, con un promedio de 1,16 mL/m3. Se apreció un elevado porcentaje (73%) con valores menores a 1,0 mL/m3. La comunidad planctónica fue muy variada, destacando diferentes organismos del zooplancton. En el fitoplancton resaltaron especies neríticas y de alta tasa de reproducción; diatomeas oceánicas predominaron a distancias mayores de 60 mn. Los dinoflagelados no abundaron pero se distribuyeron ampliamente con mayor riqueza de especies termófilas a distancias mayores de 30 mn.
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Presenta datos de barcos mercantes y de la marina que operan frente a la costa peruana, así como de estaciones y plantas industriales distribuídas a lo largo del litortal, los cuales facilitan información sobre la temperatura superficial del mar y otras complementarias, con el fin de orientar a la actividad pesquera e industrias conexas para un aprovechamiento efectivo de los recursos, haciendo prediucciones a corto y largo plazo sobre las condiciones del mar.
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BACKGROUND: Eosinophilic esophagitis (EoE) is a chronic-inflammatory disease of the esophagus, characterized by esophagus-related symptoms and a dense tissue eosinophilia, both refractory to proton pump inhibitors. Topical corticosteroids have proven effective in inducing clinical and histologic remission. However, a long-term strategy for the management of this chronic disease is not yet defined. METHODS: In a randomized, double-blind, placebocontrolled, long-term trial, we evaluated the efficacy of twice-daily 0.25 mg swallowed budesonide in maintaining a remission in adult EoE with prior response to induction therapy. Pre- and post-treatment disease activity was assessed clinically, endoscopically, histologically, by immunofluorescence and by high-resolution endosonography. The primary end point was the ability to maintain histologic remission (<5 eos/hpf) of EoE in. Secondary end points were the efficacy on symptom control and on tissue remodeling as well as the determination of the safety of long-term esophageal administration of topical corticosteroids. RESULTS: During a 50-week therapy of quiescent EoE with low-dose budesonide the esophageal eosinophil load (ECP staining) increased from 1.1 to 29.9 eos/hpf, but under placebo the increase was significantly larger (0.5 to 51.1 eos/hpf; p=0.01). At the end of the studyperiod, 35.7% (5/14) of the budesonide patients were in complete and 14.3% (2/14) in partial histologic remission; with placebo no patient was in complete and 28.6% (4/14) were in partial remission (p=0.0647). The increase of the symptom score was markedly lower in budesonide- (0.79 to 2.29 points) than in placebo-patients (0.71 to 4.00 points; p=0.0875). The median time to relapse of symptoms was >125 days in the budesonide and 95 days in the placebo group (p = 0.14). Measured by high-resolution endosonography, all EoE patients had pre-treatment a highly thickened esophageal wall compared with healthy controls (3.05±1.08 mm vs. 2.18±0.35 mm; p<0.0001). Long-term topical budesonide reduced mainly the thickness of the superficial wall layers (mucosa, 0.75 mm to 0.45 mm; p=0.025) whereas the response of the deeper layers was less pronounced (submucosa 1.31 to 1.08 mm; p=0.19 and muscularis 0.82 to 0.76 mm; p=0.72). Budesonide did not evoke any mucosal atrophy. CONCLUSIONS: This study clearly demonstrates that 1) Untreated eosinophil inflammation results in an impressive remodeling of the esophagus; 2) A therapy is therefore needed; 3) The high relapse rate after short-term therapy requires a long-term management and 4) Maintenance treatment with budesonide is well tolerated and keeps half of the patients in remission.
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Brinda información sobre la temperatura superficial del mar, con el fin de orientar a la actividad pesquera e industrias conexas para un aprovechamiento efectivo de los recursos, haciendo predicciones a corto y largo plazo sobre las condiciones del mar.
Resumo:
Brinda información sobre la temperatura superficial del mar, con el fin de orientar a la actividad pesquera e industrias conexas para un aprovechamiento efectivo de los recursos, haciendo predicciones a corto y largo plazo sobre las condiciones del mar.
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AIM: The specific natural history of superficial soft tissue sarcomas (S-STS) has been rarely considered. We describe the clinical characteristics of a large series of S-STS (N=367) from the French Sarcoma Group (GSF-GETO) database and analyse the prognostic factors affecting outcome. METHODS: We performed univariate and multivariate analyses for overall survival (OS), metastasis-free survival (MFS) and local recurrence-free survival (LRFS). RESULTS: The median age was 59 years. Fifty-eight percent patients were female. Tumour locations were as follows: extremities, 55%; trunk wall, 35.4%; head and neck, 8% and unknown, 1.6%. Median tumour size was 3.0 cm. The most frequent tumour types were unclassified sarcoma (24.3%) and leiomyosarcoma (22.3%). Thirty-three percent of cases were grade 3. Median follow-up was 6.18 years. The 5-year OS, MFS and LRFS rates were 80.9%, 80.7% and 74.7%, respectively. Multivariate analysis retained histological type and wide resection for predicting LRFS and histological type and grade as prognostic factors of MFS. The factors influencing OS were age, histological type, grade and wide resection. STS with early invasion into but not through the underlying fascia had a significantly poorer MFS than with strict S-STS. CONCLUSION: S-STS represent a separate category characterised by a better outcome. Adequate surgery, i.e. wide resection, is essential in the management of S-STS.
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Brinda información sobre la temperatura superficial del mar, con el fin de orientar a la actividad pesquera e industrias conexas para un aprovechamiento efectivo de los recursos, haciendo predicciones a corto y largo plazo sobre las condiciones del mar.
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Brinda información sobre la temperatura superficial del mar, con el fin de orientar a la actividad pesquera e industrias conexas para un aprovechamiento efectivo de los recursos, haciendo predicciones a corto y largo plazo sobre las condiciones del mar. Concluye que hay presencia de anomalías térmicas cuyos valores absolutos fueron mayores frente a Talara - Punta Aguja, frente a Punta Doña María y frente a Ilo. De otro lado, las anomalías positivas aparecieron frente a Chimbote - Huarmey y alrededor de San Juan.
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Refiere a una franja de mar que se extendió hasta las 80 millas lejos de la costa. La temperatura máxima se observó frente a Talara, y la mínima frente a Ilo, ambas muy cerca de la costa. Las áreas más frías, consecuencia del afloramiento costero, se presentaron frente a San Juan - Atico e Ilo, con temperaturas menores a 16 y 15º, respectivamente. Las aguas calientes, con temperaturas mayores a 19º C, se pegaron a la costa al sur de Punta Aguja y frente a Chimbote.
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Presenta las anomalías térmicas presentadas en la costa del Perú, las cuales presentan temperaturas debajo del promedio en toda el área observada.
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Desarrolla las anomalías térmicas presentadas en el área observada desde Tumbes hasta Punta Aguja en la costa sur.
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Describe las características más sobresalientes de la superficie del mar, incuyendo datos como: la temperatura más alta, las áreas más frías, isotermina y el frente acuatirail .