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11.
1003 is a multipotential embryonal carcinoma (EC) clonal cell line which can be induced to follow different developmental pathways by altering the composition of the culture medium. When grown in serum-containing medium the great majority of 1003 cells remain undifferentiated; they express the ECMA 7 cell-surface embryonic antigen and very low amounts of vimentin. In serum-free medium, most 1003 cells differentiate into neuroepithelial cells. The majority of these cells are still labelled with ECMA 7 antibodies. They contain higher amounts of vimentin than EC cells, but no neurofilament proteins. Neuroepithelial cells then differentiate into neurons through a stage of preneurons containing both vimentin and the 70-K neurofilament protein. Fully differentiated neurons contain 70-K neurofilament protein but no vimentin. The 200-K neurofilament protein is detected later in the neurons. Mesenchymal cells (induced by re-adding serum) express high amounts of vimentin organized in networks. Preneurons , neurons, and mesenchymal cells do not express ECMA 7 antigen.  相似文献   
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The adaptation of translocated organisms to a new environment in the first years after their release is crucial in translocation programs because it may affect survival and reproductive success. Therefore, identifying the factors determining resource selection by the relocated animals is essential to improve the planning and the outcome of such programs. Using data collected in 2006–2009 in the framework of a restocking program, we studied the temporal variation of habitat selection in 14 translocated Alpine ibex (Capra ibex) during the year of their release and the following 3 years. We hypothesized a progressive adaptation of the translocated individuals, highlighted by a gradual decrease in the dissimilarities between translocated and resident individuals in ecological characteristics and social behavior. We tested the differences in habitat selection and home range size between the translocated and resident individuals and compared the spatial overlap between the groups. As expected, the dissimilarities decreased annually. The translocated and resident ibex almost immediately selected the same habitat resources, but the translocated individuals required 3 years to become fully socially assimilated. Our results indicated that habitat selection by gregarious species in a new environment is primarily driven by specific ecological requirements and that sociality plays a significant role. The translocated individuals tended to colonize areas already occupied by residents, either to fulfill social requirements and/or because the location of resident individuals may indicate high-quality habitat. This pattern of behavior must be considered in the planning of translocation programs because habitat selection can affect the outcomes of the programs. © 2013 The Wildlife Society.  相似文献   
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There is a lack of standardized country-specific environmental data to combine with nutritional and dietary data for assessing the environmental impact of individual diets in epidemiology surveys, which are consequently reliant on environmental food datasets based on values retrieved from a heterogeneous literature. The aim of this study was to compare and assess the relative strengths and limits of a database of food greenhouse gas emissions (GHGE) values estimated with a hybrid method combining input/output and LCA approaches, with a dataset of GHGE values retrieved from the literature. France is the geographical perimeter considered in this study, but the methodology could be applied to other countries. The GHGE of 402 foodstuffs, representative of French diet, were estimated using the hybrid method. In parallel, the GHGE of individual foods were collected from existing literature. Median per-food-category GHGE values from the hybrid method and the reviewed literature were found to correlate strongly (Spearman correlation was 0.83), showing similar rankings of food categories. Median values were significantly different for only 5 (out of 29) food categories, including the ruminant meats category for which the hybrid method gave lower estimates than those from existing literature. Analysis also revealed that literature values came from heterogeneous studies that were not always sourced and that were conducted under different LCA modeling hypotheses. In contrast, the hybrid method helps build reliably-sourced, representative national standards for product-based datasets. We anticipate this hybrid method to be a starting point for better environmental impact assessments of diets.  相似文献   
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The aim of this research was to determine whether all memory T cells have the same propensity to migrate to the joint in patients with juvenile idiopathic arthritis. Paired synovial fluid and peripheral blood mononuclear cell proliferative responses to a panel of antigens were measured and the results correlated with a detailed set of laboratory and clinical data from 39 patients with juvenile idiopathic arthritis. Two distinct patterns of proliferative response were found in the majority of patients: a diverse pattern, in which synovial fluid responses were greater than peripheral blood responses for all antigens tested; and a restricted pattern, in which peripheral blood responses to some antigens were more vigorous than those in the synovial fluid compartment. The diverse pattern was generally found in patients with a high acute phase response, whereas patients without elevated acute phase proteins were more likely to demonstrate a restricted pattern. We propose that an association between the synovial fluid T cell repertoire and the acute phase response suggests that proinflammatory cytokines may influence recruitment of memory T cells to an inflammatory site, independent of their antigen specificity. Additionally, increased responses to enteric bacteria and the presence of αEβ7 T cells in synovial fluid may reflect accumulation of gut associated T cells in the synovial compartment, even in the absence of an elevated acute phase response. This is the first report of an association between the acute phase response and the T cell population recruited to an inflammatory site.  相似文献   
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Rates and patterns of evolution in partial sequences of five mitochondrial genes (cytochrome b, ATPase 6, NADH dehydrogenase subunit 5, tRNA(Glu), and the control region) were compared among taxa in the passerine bird genera Fringilla and Carduelis. Rates of divergence do not vary significantly among genes, even in comparisons with the control region. Rate variation among lineages is significant only for the control region and NADH dehydrogenase subunit 5, and patterns of variation are consistent with the expectations of neutral theory. Base composition is biased in all genes but is stationary among lineages, and there is evidence for directional mutation pressure only in the control region. Despite these similarities, patterns of substitution differ among genes, consistent with alternative regimes of selective constraint. Rates of nonsynonymous substitution are higher in NADH dehydrogenase subunit 5 than in other protein-coding genes, and transitions exist in elevated proportions relative to transversions. Transitions appear to accumulate linearly with time in tRNA(Glu), and despite exhibiting the highest overall rate of divergence among species, there are no transversional changes in this gene. Finally, for resolving phylogenetic relationships among Fringilla taxa, the combined protein-coding data are broadly similar to those of the control region in terms of phylogenetic informativeness and statistical support.   相似文献   
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BiP is found in association with calreticulin, both in the presence and absence of endoplasmic reticulum stress. Although the BiP-calreticulin complex can be disrupted by ATP, several properties suggest that the calreticulin associated with BiP is neither unfolded nor partially or improperly folded. (1) The complex is stable in vivo and does not dissociate during 8 hr of chase. (2) When present in the complex, calreticulin masks epitopes at the C terminus of BiP that are not masked when BiP is bound to an assembly-defective protein. And (3) overproduction of calreticulin does not lead to the recruitment of more BiP into complexes with calreticulin. The BiP-calreticulin complex can be disrupted by low pH but not by divalent cation chelators. When the endoplasmic reticulum retention signal of BiP is removed, complex formation with calreticulin still occurs, and this explains the poor secretion of the truncated molecule. Gel filtration experiments showed that BiP and calreticulin are present in distinct high molecular weight complexes in which both molecules interact with each other. The possible functions of this complex are discussed.  相似文献   
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IntroductionWhether diabetes mellitus increases the risk of acute kidney injury (AKI) during sepsis is controversial.ResultsFirst, we compared 451 patients with severe sepsis or septic shock and diabetes to 3,277 controls with severe sepsis or septic shock and without diabetes. Then, we compared 318 cases (with diabetes) to 746 matched controls (without diabetes). Diabetic patients did not have a higher frequency of AKI (hazard ratio [HR], 1.18; P = 0.05]) or RRT (HR, 1.09; P = 0.6). However, at discharge, diabetic patients with severe sepsis or septic shock who experienced acute kidney injury during the ICU stay and were discharged alive more often required RRT (9.5% vs. 4.8%; P = 0.02), had higher serum creatinine values (134 vs. 103 µmoL/L; P<0.001) and had less often recovered a creatinine level less than 1.25 fold the basal creatinine (41.1% vs. 60.5%; P<0.001).ConclusionsIn patients with severe sepsis or septic shock, diabetes is not associated with occurrence of AKI or need for RRT but is an independent risk factor for persistent renal dysfunction in patients who experience AKI during their ICU stay.  相似文献   
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