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The involvement of the sensorimotor system in language understanding has been widely demonstrated. However, the role of context in these studies has only recently started to be addressed. Though words are bearers of a semantic potential, meaning is the product of a pragmatic process. It needs to be situated in a context to be disambiguated. The aim of this study was to test the hypothesis that embodied simulation occurring during linguistic processing is contextually modulated to the extent that the same sentence, depending on the context of utterance, leads to the activation of different effector-specific brain motor areas. In order to test this hypothesis, we asked subjects to give a motor response with the hand or the foot to the presentation of ambiguous idioms containing action-related words when these are preceded by context sentences. The results directly support our hypothesis only in relation to the comprehension of hand-related action sentences.  相似文献   
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A series of twenty-five derivatives of tetrahydro-β-carbolines 13 was synthesized and assayed on FAAH and TRPV1 and TRPA1 channels. Four carbamates, that is, 5a,c,e, and 9b inhibited FAAH with significant potency and interacted also effectively with TRPV1 and TRPA1 nociceptive receptors, while ureas 7b,d,f, and 8a,b were endowed with specific submicromolar TRPV1 modulating activities.  相似文献   
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Climatic change and its ecological implications at a subantarctic island   总被引:7,自引:0,他引:7  
Summary Marion Island (47°S, 38°E) has one of the most oceanic climates on earth, with consistently low air temperatures, high precipitation, constantly high humidity, and low incident radiation. Since 1968 mean surface air temperature has increased significantly, by 0.025° C year–1. This was strongly associated with corresponding changes in sea surface temperature but only weakly, or not at all, with variations in radiation and precipitation. We suggest that changing sealevel (atmospheric and oceanic) circulation patterns in the region underlie all of these changes. Sub-Antarctic terrestrial ecosystems are characterized by being species-poor and having a simple trophic structure. Marion Island is no exception and a scenario is presented of the implications of climatic change for the structure and functioning of its ecosystem. Primary production on the island is high and consequently the vegetation has a large annual requirement for nutrients. There are no macroherbivores and even the insects play only a small role as herbivores, so most of the energy and nutrients incorporated in primary production go through a detritus, rather than grazing, cycle. Ameliorating temperatures and increasing CO2 levels are expected to increase productivity and nutrient demand even further. However, most of the plant communities occur on soils which have especially low available levels of nutrients and nutrient mineralization from organic reserves is the main bottleneck in nutrient cycling and primary production. Increasing temperatures will not significantly enhance microbially-mediated mineralization rates since soil microbiological processes on the island are strongly limited by waterlogging, rather than by temperature. The island supports large numbers of soil macro-arthropods, which are responsible for most of the nutrient release from peat and litter. The activities of these animals are strongly temperature dependent and increasing temperature will result in enhanced nutrient availability, allowing the potential for increased primary production due to elevated temperature and CO2 levels to be realized. However, housemice occur on the island and have an important influence on the ecosystem, mainly by feeding on soil invertebrates. The mouse population is strongly temperature-limited and appears to be increasing, possibly as a result of ameliorating temperatures. We suggest that an increasing mouse population, through enhanced predation pressure on soil invertebrates, will decrease overall rates of nutrient cycling and cause imbalances between primary production and decomposition. This, along with more direct effects of mice (e.g. granivory) has important implications for vegetation succession and ecosystem structure and functioning on the island. Some of these are already apparent from comparisons with nearby Prince Edward Island where mice do not occur. Other implications of climatic change for the island are presented which emphasize the very marked influences that invasive organisms have on ecosystem structure and functioning. We suggest that changing sealevel circulation patterns, by allowing opportunities for colonization by new biota, may have an even more important influence on terrestrial sub-Antarctic ecosystems than is suggested merely on the basis of associated changes in temperature or precipitation.  相似文献   
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Hypoxic preconditioning (HPC) may protect multiple organs from various injuries. We hypothesized that HPC would reduce lung injury in patients undergoing thoracoscopic lobectomy. In a prospective randomized controlled trial, 70 patients undergoing elective thoracoscopic lobectomy were randomly allocated to the HPC group or the control group. Three cycles of 5-min hypoxia and 3-min ventilation applied to the nondependent lung served as the HPC intervention. The primary outcome was the PaO2/FiO2 ratio. Secondary outcomes included postoperative pulmonary complications, pulmonary function, and duration of hospital stay. HPC significantly increased the PaO2/FiO2 ratio compared with the control at 30 min after one-lung ventilation and 7 days after operation. Compared with the control, it also significantly improved postoperative pulmonary function and markedly reduced the postoperative hospital stay duration. No significant differences between groups were observed in the incidence of pulmonary complications or overall postoperative morbidity. HPC improves postoperative oxygenation, enhances the recovery of pulmonary function, and reduces the duration of hospital stay in patients undergoing thoracoscopic lobectomy. This study was registered in the Chinese Clinical Trial Registry (ChiCTR-IPR-17011249) on April 27, 2017.  相似文献   
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IntroductionEarly degenerative changes in the nucleus pulposus (NP) are observed after the disappearance of notochordal cells (NCs). Thus, it has been suggested that NCs play an important role in maintaining the NP and may have a regenerative potential on other cells of the NP. As the number of resident NP cells (NPCs) decreases in a degenerating disc, mesenchymal stromal (stem) cells (MSCs) may be used for cell supplementation. In this study, using cells of one species, the regenerative potential of canine NCs was assessed in long-term three-dimensional coculture with canine NPCs or MSCs.MethodsCanine NCs and canine NPCs or MSCs were cocultured in alginate beads for 28 days under hypoxic and high-osmolarity conditions. Cell viability, cell morphology and DNA content, extracellular matrix production and expression of genes related to NC markers (Brachyury, KRT18) and NP matrix production (ACAN, COL2A1, COL1A1) were assessed after 1, 15 and 28 days of culture.ResultsNCs did not completely maintain their phenotype (morphology, matrix production, gene expression) during 28 days of culture. In cocultures of NPCs and NCs, both extracellular matrix content and anabolic gene expression remained unchanged compared with monoculture groups, whereas cocultures of MSCs and NCs showed increased glycosaminoglycan/DNA. However, the deposition of these proteoglycans was observed near the NCs and not the MSCs. Brachyury expression in the MSC and NC coculture group increased in time. The latter two findings indicate a trophic effect of MSCs on NCs rather than vice versa.ConclusionsNo regenerative potential of canine NCs on canine NPCs or MSCs was observed in this study. However, significant changes in NC phenotype in long-term culture may have resulted in a suboptimal regenerative potential of these NCs. In this respect, NC-conditioned medium may be better than coculture for future studies of the regenerative potential of NCs.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-015-0569-6) contains supplementary material, which is available to authorized users.  相似文献   
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BackgroundDespite some preliminary evidence, it is still largely unknown whether osteopathic manipulative treatment improves preterm clinical outcomes.ResultsA total of 695 newborns were randomly assigned to either the study group (n= 352) or the control group (n=343). A statistical significant difference was observed between the two groups for the primary outcome (13.8 and 17.5 days for the study and control group respectively, p<0.001, effect size: 0.31). Multivariate analysis showed a reduction of the length of stay of 3.9 days (95% CI -5.5 to -2.3, p<0.001). Furthermore, there were significant reductions with treatment as compared to usual care in cost (difference between study and control group: 1,586.01€; 95% CI 1,087.18 to 6,277.28; p<0.001) but not in daily weight gain. There were no complications associated to the intervention.ConclusionsOsteopathic treatment reduced significantly the number of days of hospitalization and is cost-effective on a large cohort of preterm infants.  相似文献   
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