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991.
Further to the Epinal events, Health Ministers P. Bas then R. Bachelot-Narquin have launched a plan of work devoted to radiotherapy; they have also committed the SFRO President, within the framework of a mission, to make proposals taking into account the demography of professionals and their level of competence, valorization of careers, cooperation with medical oncologists, delegations of authorities, mutualisation of human and material resources. Due to the numerous actions of the roadmap managed by the tutelages, the aim of the mission was focused on the modalities of work of the professionals linked to radiotherapy: radiation oncologists, radiographers and physicists.  相似文献   
992.
For the second year, the French Radiotherapy Database presents information from French radiation oncology centers. Among 179 centers, 159 have participated (90 %). The number of accelerators increased from 371 to 384 between 2006 and 2007, 11 % of these machines are more than 15 years old. On average, centers are open 50 hours per week for treatment and 9.5 % more for maintenance. The lack of dedicated CT remains a difficulty: 158 from 159 centers have an access to a CT, but only 50 % have a dedicated scanner. There is no progress compared to 2006. The proportion of centers having a MU double calculation system has increased from 51 to 58 %. Two thirds of centers do not implement in vivo dosimetry. The activity is stable around 190 000 treatments per year. Three-dimension conformal radiotherapy is used for more than half of treatments in 77.2 % of private centers and 50 % of public hospitals. Intensity modulated radiotherapy remains rarely used. The number of radiation oncologists and technologists remains stable. The number of radiophysicists has increased from 7.6 %. Despite some progress, the difficulties of this speciality persist in France and are equally distributed across all regions, and between private and public centers. In 2009, the French Society for Radiation Oncology and the associated partners will continue this survey, which interest is recognized by both professionals and health administrations.  相似文献   
993.
Staphylococcal scalded skin syndrome is the term used for a spectrum of primarily neonatal blistering skin diseases caused by the exfoliative toxins, ETA and ETB, of Staphylococcus aureus  相似文献   
994.
995.
A small number of circulating proteins have been reported to be associated with breast cancer risk, with inconsistent results. Herein, we attempted to identify novel protein biomarkers for breast cancer via the integration of genomics and proteomics data. In the Breast Cancer Association Consortium (BCAC), with 122,977 cases and 105,974 controls of European descendants, we evaluated the associations of the genetically predicted concentrations of >1,400 circulating proteins with breast cancer risk. We used data from a large-scale protein quantitative trait loci (pQTL) analysis as our study instrument. Summary statistics for these pQTL variants related to breast cancer risk were obtained from the BCAC and used to estimate odds ratios (OR) for each protein using the inverse-variance weighted method. We identified 56 proteins significantly associated with breast cancer risk by instrumental analysis (false discovery rate <0.05). Of these, the concentrations of 32 were influenced by variants close to a breast cancer susceptibility locus (ABO, 9q34.2). Many of these proteins, such as insulin receptor, insulin-like growth factor receptor 1 and other membrane receptors (OR: 0.82–1.18, p values: 6.96 × 10−4–3.28 × 10−8), are linked to insulin resistance and estrogen receptor signaling pathways. Proteins identified at other loci include those involved in biological processes such as alcohol and lipid metabolism, proteolysis, apoptosis, immune regulation and cell motility and proliferation. Consistent associations were observed for 22 proteins in the UK Biobank data (p < 0.05). The study identifies potential novel biomarkers for breast cancer, but further investigation is needed to replicate our findings.  相似文献   
996.
While the HTT CAG‐repeat expansion mutation causing Huntington's disease (HD) is highly correlated with the rate of pathogenesis leading to disease onset, considerable variance in age‐at‐onset remains unexplained. Therefore, other factors must influence the pathogenic process. We asked whether these factors were related to natural biological variation in the sensory‐motor system. In 243 participants (96 premanifest and 35 manifest HD; 112 controls), sensory‐motor structural MRI, tractography, resting‐state fMRI, electrophysiology (including SEP amplitudes), motor score ratings, and grip force as sensory‐motor performance were measured. Following individual modality analyses, we used principal component analysis (PCA) to identify patterns associated with sensory‐motor performance, and manifest versus premanifest HD discrimination. We did not detect longitudinal differences over 12 months. PCA showed a pattern of loss of caudate, grey and white matter volume, cortical thickness in premotor and sensory cortex, and disturbed diffusivity in sensory‐motor white matter tracts that was connected to CAG repeat length. Two further major principal components appeared in controls and HD individuals indicating that they represent natural biological variation unconnected to the HD mutation. One of these components did not influence HD while the other non‐CAG‐driven component of axial versus radial diffusivity contrast in white matter tracts were associated with sensory‐motor performance and manifest HD. The first component reflects the expected CAG expansion effects on HD pathogenesis. One non‐CAG‐driven component reveals an independent influence on pathogenesis of biological variation in white matter tracts and merits further investigation to delineate the underlying mechanism and the potential it offers for disease modification. Hum Brain Mapp 37:4615–4628, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   
997.
We have developed a technique for inverse treatment planning of prostate therapy designed to improve the degree of conformation between the dose distribution and the target volume. We compared the inverse plan with a "standard" four-field box technique as well as a four-field technique using oblique fields ("cross technique"). We validated the dosimetry of the inverse plan using Fricke gel solution in phantom specifically designed for this purpose. The phantom is a Plexiglas tank with a cross section, which approximates the dimensions of the pelvis. Anatomical data from computed tomography (CT) images of a patient were used to simulate organs in our phantom. This allows us to calculate dose distributions with the external geometry of the phantom and internal anatomy of the patient. Dose-volume histograms (DVHs) for the three different plans were calculated. The phantom containing the Fricke gel was irradiated according to the inverse plan. Magnetic resonance (MR) images was used to determine the dose distribution delivered to the phantom. We observe, on DVHs, that the inverse plan significantly reduces the dose to the rectum and the bladder but slightly increases the inhomogeneity inside the target volume. Correlation is good between isodoses on MR images and calculated isodoses. We conclude that inverse planning software can greatly improve the conformal degree of treatment to the prostate. This technique could be applied to other complex anatomic sites at which dose to organs at risk is a limiting factor and increased dose to the target volume is indicated. Our phantom and the Fricke gel solution are convenient to carry out validation of conformal treatments.  相似文献   
998.
CONTEXT: The stress responses of the hypothalamic-pituitary-adrenal axis can produce adverse effects on the brain. Previous studies have concluded that an elevated level of cortisol is a risk factor for cognitive dysfunction and decline in aging but have been limited by sex exclusion, restricted cognitive batteries, and small sample sizes. OBJECTIVE: To examine associations among salivary cortisol metrics and cognitive domain scores in an urban adult population. Design, Setting, and PARTICIPANTS: A cross-sectional analysis was conducted using data from a longitudinal study involving 1140 Baltimore, Maryland, residents aged 50 to 70 years. Four salivary cortisol samples were obtained from 967 participants across 1 study visit (before, during, and after cognitive testing as well as at the end of the visit) from which 7 cortisol metrics were created. We examined associations of cortisol metrics with cognitive performance using multiple linear regression. MAIN OUTCOME MEASURES: Performance on 20 standard cognitive tests was measured and combined to form summary measures in 7 domains (language, processing speed, eye-hand coordination, executive functioning, verbal memory and learning, visual memory, and visuoconstruction). RESULTS: Higher levels of pretest and mean cortisol as well as the area under the curve of cortisol over the study visit were associated with worse performance (P < .05) in 6 domains (language, processing speed, eye-hand coordination, executive functioning, verbal memory and learning, and visual memory). For instance, an interquartile range increase in the area under the curve was equivalent to a decrease in the language score expected from an increase in 5.6 (95% confidence interval, 4.2-7.1) years of age. CONCLUSIONS: Elevated cortisol was associated with poorer cognitive function across a range of domains in this large population-based study. We believe the findings are consistent with the hypothesis that hypothalamic-pituitary-adrenal axis dysregulation may be a risk factor for poorer cognitive performance in older persons.  相似文献   
999.
BackgroundAcute flaccid myelitis (AFM) is a polio-like condition affecting mainly children and involving the central nervous system (CNS). AFM has been associated with different non-polio-enteroviruses (EVs), in particular EV-D68 and EV-A71. Reliable incidence rates in European countries are not available.AimTo report AFM incidence in children in the Netherlands and its occurrence relative to EV-D68 and EV-A71 detections.MethodsIn 10 Dutch hospitals, we reviewed electronic health records of patients diagnosed with a clinical syndrome including limb weakness and/or CNS infection and who were < 18 years old when symptoms started. After excluding those with a clear alternative diagnosis to AFM, those without weakness, and removing duplicate records, only patients diagnosed in January 2014–December 2019 were retained and further classified according to current diagnostic criteria. Incidence rates were based on definite and probable AFM cases. Cases’ occurrences during the study period were co-examined with laboratory-surveillance detections of EV-D68 and EV-A71.ResultsAmong 143 patients included, eight were classified as definite and three as probable AFM. AFM mean incidence rate was 0.06/100,000 children/year (95% CI: −0.03 to 0.14). All patient samples were negative for EV-A71. Of respiratory samples in seven patients, five were EV-D68 positive. AFM cases clustered in periods with increased EV-D68 and EV-A71 detections.ConclusionsAFM is rare in children in the Netherlands. The temporal coincidence of EV-D68 circulation and AFM and the detection of this virus in several cases’ samples support its association with AFM. Increased AFM awareness among clinicians, adequate diagnostics and case registration matter to monitor the incidence.  相似文献   
1000.
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