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OBJECTIVE: To investigate the usefulness of the polymerase chain reaction (PCR) to detect B cell clonal expansions in tissues where lymphoproliferative disease was suspected in the course of Sj?gren's syndrome (SS). METHODS: Tissue samples from 7 patients with definite (5 cases) or probable (2 cases) SS were subjected to routine histopathologic studies, immunophenotyping, and genotypic analysis, including Southern blotting and PCR amplification of immunoglobulin heavy chain (IgH) variable-diversity-joining (VDJ) region gene rearrangements. RESULTS: Malignant lymphoma was detected in 3 cases, and myoepithelial sialadenitis in the remaining 4. B cell clonal expansion was detected in 7/7 cases by PCR, 5/7 by Southern blotting, and in no case of myoepithelial sialadenitis by kappa/lambda light chain immunophenotyping. CONCLUSION: PCR may represent a quick and powerful tool to detect B cell clonalities in SS. Such information may provide new insights into the pathogenesis of the disease and may improve the clinical approach to the patients.  相似文献   
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Existing tools for automatically detecting Web site defacement compare monitored Web resources with uncorrupted copies of the content kept in a safe place. This can be an expensive and difficult task, especially when working with dynamic resources. In contrast, the Goldrake tool uses sensors and alarms to automatically monitor remote Web resources' integrity. Such a framework could help designers build services to inexpensively monitor multiple Web sites, which could be very attractive for small, budget-limited organizations that depend on the Web for their operation  相似文献   
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Relatively little is known about the occurrence of neurocysticercosis in northeastern Brazil. There have been no published reports from the state of Ceará, but a review of the records at the Hospital S?o José in Fortaleza, Brazil identified 119 patients with neurocysticercosis diagnosed between January 1988 and April 1994. Patients came from 43 municipalities in Ceará. Their ages ranged from five to 74 years; the greatest number of cases were in persons 10-40 years of age; 63% were males. Seizures were the presenting complaint in 64% of the patients and headache in 22%. Two patients, each with several hundred intracranial lesions, presented with mental status changes; one was initially given the clinical diagnosis of viral meningoencephalitis. Computed tomography scans showed that 44% of the patients had five or more lesions. Cysts were found throughout the brain. The parietal lobe was the most frequent site of involvement; 85% of patients had one or more lesions there. The brain stem was involved in 8%. There was no consistent association between the severity of the clinical abnormalities and the radiologic findings. Computed tomography of the thighs was done in 10 persons; cysts were identified in nine.  相似文献   
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The aim of this work is to demonstrate the use of a commercial finite element package, ABAQUS EXPLICIT, to model ultrasonic guided waves in structural components. The particular application of interest is modeling the interaction of a broadband vertical bending mode with transverse-type defects in railroad tracks. This topic is part of a broader project on high-speed defect detection in rails by long-range ultrasonic inspections. Reflection coefficient spectra in the 20–45 kHz range are obtained for four different sizes and three different orientations of transverse head flaws. A preliminary study of Lamb waves in a free plate helps drawing modeling guidelines for the rail.  相似文献   
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The control of the fungal contamination on crops is considered a priority by the sanitary authorities of an increasing number of countries, and this is also due to the fact that the geographic areas interested in mycotoxin outbreaks are widening. Among the different pre- and post-harvest strategies that may be applied to prevent fungal and/or aflatoxin contamination, fungicides still play a prominent role; however, despite of countless efforts, to date the problem of food and feed contamination remains unsolved, since the essential factors that affect aflatoxins production are various and hardly to handle as a whole. In this scenario, the exploitation of bioactive natural sources to obtain new agents presenting novel mechanisms of action may represent a successful strategy to minimize, at the same time, aflatoxin contamination and the use of toxic pesticides. The Aflatox® Project was aimed at the development of new-generation inhibitors of aflatoxigenic Aspergillus spp. proliferation and toxin production, through the modification of naturally occurring molecules: a panel of 177 compounds, belonging to the thiosemicarbazones class, have been synthesized and screened for their antifungal and anti-aflatoxigenic potential. The most effective compounds, selected as the best candidates as aflatoxin containment agents, were also evaluated in terms of cytotoxicity, genotoxicity and epi-genotoxicity to exclude potential harmful effect on the human health, the plants on which fungi grow and the whole ecosystem.  相似文献   
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An automatic method to combine several local surrogate models is presented. This method is intended to build accurate and smooth approximation of discontinuous functions that are to be used in structural optimization problems. It strongly relies on the Expectation−Maximization (EM) algorithm for Gaussian mixture models (GMM). To the end of regression, the inputs are clustered together with their output values by means of parameter estimation of the joint distribution. A local expert is then built (linear, quadratic, artificial neural network, moving least squares) on each cluster. Lastly, the local experts are combined using the Gaussian mixture model parameters found by the EM algorithm to obtain a global model. This method is tested over both mathematical test cases and an engineering optimization problem from aeronautics and is found to improve the accuracy of the approximation.  相似文献   
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Examination of blood viscosity at low shear rates using a co-axial cylinder viscometer showed a significant difference between the means of values observed in hypertrigliceridemic patients compared with that of control subjects. This result differs from what has been reported by most workers although generally greater shear rates have been used. Calculation of the "r" coefficient and plotting of the regression line for each shear rate showed that there is no linear correlation between blood viscosity and triglyceridaemia, whose variations occur quite independently. It is suggested that the absence of a correlation between the two parameters examined may depend on various factors, of which the most important are those pertaining to the rheological properties of red blood cells and to the structure and chemical and physical characteristics of the triglyceride molecule and of the lipoproteins and chylomicrons which transport them.  相似文献   
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This research has two main purposes. The first is to replicate and possibly to extend the results obtained in a previous study, where the authors found that visitors to the ancient art museum conducted their visit with the primary aim of acquiring understanding and knowledge, while modern art museum visitors conducted their visit with an approach that was primarily emotional and pleasure-seeking. The second purpose relates to studies showing that people who prefer abstract art present higher levels on personality traits like “Openness to Experience” and “Sensation Seeking,” compared to people who prefer realistic art. This study investigates these two personality traits for people who favor visiting museums of ancient rather than modern art. Results confirmed previous findings that emotional aspects related to the visit were relevant for modern art museum visitors, while a more cognitive approach based on learning characterized ancient art museum visitors. Concerning personality traits, no difference was found between the two museum groups on the “Openness to Experience” dimension; differences were found on the “Sensation Seeking” trait; modern art museum visitors attained higher scores as compared to ancient art museum visitors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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