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51.
Razani Jill; Chan Agnes; Nordin Steven; Murphy Claire 《Canadian Metallurgical Quarterly》2010,24(3):291
Objective: Impairment in odor-naming ability and in verbal and visual semantic networks raised the hypothesis of a breakdown in the semantic network for odors in Alzheimer's disease (AD). The current study addressed this hypothesis. Method: Twenty-four individuals, half patients with probable AD and half control participants, performed triadic-similarity judgments for odors and colors, separately, which, utilizing the multidimensional scaling (MDS) technique of individual difference scaling analysis (INDSCAL), generated two-dimensional configurations of similarity. The abilities to match odors and colors with written name labels were assessed to investigate disease-related differences in ability to identify and conceptualize the stimuli. In addition, responses on attribute-sorting tasks, requiring the odor and color perceptions to be categorized as one polarity of a certain dimension, were obtained to allow for objective interpretation of the MDS spatial maps. Results: Whereas comparison subjects generated spatial maps based predominantly on relatively abstract characteristics, patients with AD classified odors on perceptual characteristics. The maps for patients with AD also showed disorganized groupings and loose associations between odors. Their normal configurations for colors imply that the patients were able to comprehend the task per se. The data for label matching and for attribute sorting provide further evidence for a disturbance in semantic odor memory in AD. The patients performed poorer than controls on both these odor tasks, implying that the ability to identify and/or conceptualize odors is impaired in AD. Conclusion: The results provide clear evidence for deterioration of the structure of semantic knowledge for odors in AD. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Faria CB Abe CA da Silva CN Tessmann DJ Barbosa-Tessmann IP 《International journal of molecular sciences》2012,13(1):115-132
Fusarium verticillioides and Fusarium subglutinans are important fungal pathogens of maize and other cereals worldwide. In this study, we developed PCR-based protocols for the identification of these pathogens targeting the gaoB gene, which codes for galactose oxidase. The designed primers recognized isolates of F. verticillioides and F. subglutinans that were obtained from maize seeds from several producing regions of Brazil but did not recognize other Fusarium spp. or other fungal genera that were either obtained from fungal collections or isolated from maize seeds. A multiplex PCR protocol was established to simultaneously detect the genomic DNA from F. verticillioides and F. subglutinans. This protocol could detect the DNA from these fungi growing in artificially or naturally infected maize seeds. Another multiplex reaction with a pair of primers developed in this work combined with a pre-existing pair of primers has allowed identifying F. subglutinans, F. konzum, and F. thapsinum. In addition, the identification of F. nygamai was also possible using a combination of two PCR reactions described in this work, and another described in the literature. 相似文献
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Agnes Schrder Andrea Meyer Gerrit Spanier Anna Damanaki Eva Paddenberg Peter Proff Christian Kirschneck 《International journal of molecular sciences》2021,22(13)
Orthodontic treatment to correct dental malocclusions leads to the formation of pressure zones in the periodontal ligament resulting in a sterile inflammatory reaction, which is mediated by periodontal ligament fibroblasts (PDLF). Leptin levels are elevated in obesity and chronic inflammatory responses. In view of the increasing number of orthodontic patients with these conditions, insights into effects on orthodontic treatment are of distinct clinical relevance. A possible influence of leptin on the expression profile of PDLF during simulated orthodontic mechanical strain, however, has not yet been investigated. In this study, PDLF were exposed to mechanical strain with or without different leptin concentrations. The gene and protein expression of proinflammatory and bone-remodelling factors were analysed with RT-qPCR, Western-blot and ELISA. The functional analysis of PDLF-induced osteoclastogenesis was analysed by TRAP (tartrate-resistant acid phosphatase) staining in coculture with human macrophages. Pressure-induced increase of proinflammatory factors was additionally elevated with leptin treatment. PDLF significantly increased RANKL (receptor activator of NF-kB ligand) expression after compression, while osteoprotegerin was downregulated. An additional leptin effect was demonstrated for RANKL as well as for subsequent osteoclastogenesis in coculture after TRAP staining. Our results suggest that increased leptin concentrations, as present in obese patients, may influence orthodontic tooth movement. In particular, the increased expression of proinflammatory factors and RANKL as well as increased osteoclastogenesis can be assumed to accelerate bone resorption and thus the velocity of orthodontic tooth movement in the orthodontic treatment of obese patients. 相似文献
56.
Buche P Dervin C Gnanou-Besse N Brouillaud-Delattre A 《International journal of food microbiology》2002,73(2-3):171-185
Various predictive models of microbial behavior have been created and extensive data collection has been done by numerous private or public laboratories. However, significant differences between predicted and observed values in foods have been observed and need to be stressed, understood and explained as much as possible. In this paper, we present a software tool (currently at the level of a prototype) able: (i) to store in a database all relevant information expressed on one hand as qualitative or quantitative data and on the other hand as precise or imprecise data; (ii) to retrieve the more relevant information from the database using queries where criteria may be expressed as fuzzy values in order to enhance the flexibility of the search: (iii) to compute, in addition to the nearest data, an estimation of searched values using statistical models. The architecture of this software tool is structured as a category-based reasoning system. Example queries about Listeria monocytogenes (L. monocytogenes) illustrate the functionalities of this tool. 相似文献
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The fluorescence emission and photodegradation properties of fluorescein dye inside fluid-filled spherical nanoreactors ~ 150 nm in diameter and surrounded by a few nanometres thick layer of calcium phosphate are considered in detail. Steady state, stopped flow, and laser pulsed fluorescence spectroscopies, absorption spectroscopy, dynamic light scattering and electron microscopy were used to characterize the materials as a function of encapsulated dye concentration, particle concentration, illumination time, and pH. Fluorescein tends to form stable J-aggregates inside the nanoreactors. The molecular collision rate constants between the dye aggregates and between the dyes and soluble quenchers are greatly reduced inside the nanoreactors and are responsible for the observed resistance to photodegradation and reduced emission quenching. A model for dye behaviour in nanoreactors is suggested. Nanoreactors can be concentrated to a high suspension concentration, yielding exceptionally strong luminescence affected only by inner filter effects absent particle-particle crosstalk. These and similar nanoreactors can be utilized as building blocks for three-dimensional photo-optical devices, and as versatile and resilient supramolecular chromophores or tracers in complex fluids, cells and microfluidic systems where high resolution visualization is needed. 相似文献
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Anderson Marcos Dias Canteli Fernando Augusto Pedersen Voll Agnes de Paula Scheer 《Chemical Engineering Communications》2019,206(11):1487-1497
AbstractBiosorption has been shown in the literature to be effective in the removal of dye from aqueous solution. To be fully useful, a desorption process is necessary, which has a direct impact on the process costs. The aim of this work was to evaluate the desorption of the azo dye Acid Yellow 23 adsorbed in a biosorbent obtained from Bombyx mori cocoons. Temperature and pH media were evaluated through a mixed two- and three-level design, using NaOH as desorbing agent. Kinetic desorption was also obtained at the optimized condition. The statistical evaluation of the experimental design showed that the pH has almost two times more influence on the dye desorption than the temperature, with only the linear parameters being statistically significant. Among four kinetic desorption models adjusted to the experimental data, the proposed n-order model was statistically determined as the best representation of the experimental data. 相似文献