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排序方式: 共有1485条查询结果,搜索用时 31 毫秒
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María Luz Gonzalez-Gadea Agustín Ibanez Juliane Damm Diana Andrea Ramirez Romero Sofia Abrevaya Facundo Manes 《Neurocase》2013,19(4):457-464
Previous single-case reports in posterior cortical atrophy (PCA) have shown preserved nonconscious visual recognition despite the absence of explicit recognition. In this study, we investigated three levels of visual recognition in both a female patient with PCA and a control group during the presentation of neutral, positive, and negative affective stimuli. Our results confirmed the profile of impaired explicit recognition and intact psychophysiological responses in the patient. In addition, she was able to implicitly recognize the valence and intensity of arousal of these stimuli. We suggest that implicit emotional awareness may mediates explicit and psychophysiological recognition in PCA. 相似文献
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Porcel JM Bielsa S Esquerda A Ruiz-González A Falguera M 《European Journal of Internal Medicine》2012,23(5):447-450
Background and aimsPrompt identification of parapneumonic effusions has immediate therapeutic benefits. We aimed to assess whether C-reactive protein (CRP) and routine biochemistries in pleural fluid are accurate markers of parapneumonic effusions, and to evaluate their properties as indicators for drainage (complicated parapneumonic effusion).MethodsA retrospective review of 340 non-purulent parapneumonic effusions and 1,659 non-parapneumonic exudates from a single center was performed and the discriminative properties of pleural fluid routine biochemistries and, when available, CRP were evaluated. CRP, along with classical fluid parameters, was also applied to classify patients as having complicated or uncomplicated parapneumonic effusions. ROC analysis established the threshold of CRP for discriminating between groups.ResultsPleural fluids with neutrophilic predominance and CRP levels > 45 mg/dL were most likely to be parapneumonic in origin (likelihood ratio = 7.7). When attempting to differentiate non-purulent complicated from uncomplicated effusions, a CRP > 100 mg/L had the same performance characteristics (area under the curve = 0.81) as the widely accepted biochemistries pH and glucose. Combinations of CRP with pH or glucose resulted in incrementally discriminating values, pertaining to either sensitivity (75–80%) or specificity (97%), for complicated effusions.ConclusionPleural fluid CRP may be a useful adjunctive test in pleural effusions, both as a marker of parapneumonics and, particularly, as a differentiator between complicated and uncomplicated effusions. 相似文献
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The relationship between systemic inflammation and comorbidities in patients with chronic obstructive pulmonary disease (COPD) is unclear. This article discusses (1) the prevalence and clinical impact of comorbidities in COPD; (2) the current knowledge on definition, prevalence, consequences, and treatment of systemic inflammation in COPD; and (3) the relationship of systemic inflammation and lung cancer in COPD. 相似文献
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Bone morphogenetic protein-2/4 signalling pathway components are expressed in the human thymus and inhibit early T-cell development
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Cejalvo T Sacedón R Hernández-López C Diez B Gutierrez-Frías C Valencia J Zapata AG Varas A Vicente A 《Immunology》2007,121(1):94-104
T-cell differentiation is driven by a complex network of signals mainly derived from the thymic epithelium. In this study we demonstrate in the human thymus that cortical epithelial cells produce bone morphogenetic protein 2 (BMP2) and BMP4 and that both thymocytes and thymic epithelium express all the molecular machinery required for a response to these proteins. BMP receptors, BMPRIA and BMPRII, are mainly expressed by cortical thymocytes while BMPRIB is expressed in the majority of the human thymocytes. Some thymic epithelial cells from cortical and medullary areas express BMP receptors, being also cell targets for in vivo BMP2/4 signalling. The treatment with BMP4 of chimeric human-mouse fetal thymic organ cultures seeded with CD34+ human thymic progenitors results in reduced cell recovery and inhibition of the differentiation of human thymocytes from CD4- CD8- to CD4+ CD8+ cell stages. These results support a role for BMP2/4 signalling in human T-cell differentiation. 相似文献
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In this study, we used ecological niche factor analysis (ENFA) and principal components analysis (PCA) of climate variables to define the climate niches and areas of potential colonization of six species of ticks in the Mediterranean region: Dermacentor marginatus Sulzer, Rhipicephalus bursa Canestrini & Fanzago, Rhipicephalus turanicus Pomerantsev, Matikashvili & Lototsky, Hyalomma marginatum Koch, Hyalomma excavatum Koch, and Boophilus annulatus (Say). ENFA generated distribution models that varied in accuracy from high to very high (area under the curve [AUC] = 0.87-0.97), with the lowest AUC obtained for B. annulatus. PCA provided an adequate separation of the climate niches of different species in the reduced space of the variables. Climate scenarios and factorial consensus analysis were used to evaluate the geographic impact of climate change (as turnover in habitat suitability) on the niches of the ticks and net variations in habitat availability. The scenario that was most compatible with estimates of future climate in the Mediterranean region (increase in temperature and decrease in rainfall) was predicted to produce a sharp increase in the extent of suitable habitat for R. bursa, R. turanicus, and H. marginatum. This scenario would result in a northward expansion of suitable habitat areas for these three species. The highest impact (highest species turnover) would be recorded at the margin of the current distribution range of the three species. A sensitivity analysis of the ecological response of the ticks to the climate change scenarios showed that the response is statistically different in different regions of the PCA-derived niche. These results outline the need to further investigate the potential of bioclimate models to obtain accurate estimations of tick species turnover under conditions of climate change over wide areas. 相似文献
39.
EphrinB1-EphB signaling regulates thymocyte-epithelium interactions involved in functional T cell development 总被引:1,自引:0,他引:1
Alfaro D García-Ceca JJ Cejalvo T Jiménez E Jenkinson EJ Anderson G Muñoz JJ Zapata A 《European journal of immunology》2007,37(9):2596-2605
The Eph and ephrin families are involved in numerous developmental processes. Recently, an increasing body of evidence has related these families with some aspects of T cell development. In the present study, we show that the addition of either EphB2-Fc or ephrinB1-Fc fusion proteins to fetal thymus organ cultures established from 17-day-old fetal mice decreases the numbers of both double-positive (CD4(+)CD8(+)) and single-positive (both CD4(+)CD8(-) and CD4(-)CD8(+)) thymocytes, in correlation with increased apoptosis. By using reaggregate thymus organ cultures formed by fetal thymic epithelial cells (TEC) and CD4(+)CD8(+) thymocytes, we have also demonstrated that ephrinB1-Fc proteins are able to disorganize the three-dimensional epithelial network that in vivo supports the T cell maturation, and to alter the thymocyte interactions. In addition, in an in vitro model, Eph/ephrinB-Fc treatment also decreases the formation of cell conjugates by CD4(+)CD8(+) thymocytes and TEC as well as the TCR-dependent signaling between both cell types. Finally, immobilized EphB2-Fc and ephrinB1-Fc modulate the anti-CD3 antibody-induced apoptosis of CD4(+)CD8(+) thymocytes in a process dependent on concentration. These results therefore support a role for Eph/ephrinB in the processes of development and selection of thymocytes as well as in the establishment of the three-dimensional organization of TEC. 相似文献
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Agustín Estrada-Peña Sally Cutler Aleksandar Potkonjak Muriel Vassier-Tussaut Wim Van Bortel Hervé Zeller Natalia Fernández-Ruiz Andrei Daniel Mihalca 《International journal of health geographics》2018,17(1):41