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971.
Basque nationalism is singled out in the literature as a case of minority nationalism that faces an ongoing struggle between those in support of a liberal-inclusive definition of the nation and those favouring an exclusive-racialist one. Nevertheless, Basque nationalist parties have been welcoming of immigration and have legislated to create a regional citizenship based on residence rather than ethnicity. This article argues that, at least in part, the ‘positive’ response of Basque nationalists to the immigration wave that began in the early 2000s is an attempt to strengthen national solidarity by contrasting Basque values of openness and tolerance against the restrictive nature of the reforms to the immigration law in Spain that were initiated in 2000. This argument challenges the notion that sub-state nationalists are hostile to immigration because of the threat diversity poses to the nationalist project.  相似文献   
972.
Sugarcane (Saccharum spp. hybrid) with complex polyploid genome requires a large number of informative DNA markers for various applications in genetics and breeding. Despite the great advances in genomic technology, it is observed in several crop species, especially in sugarcane, the availability of molecular tools such as microsatellite markers are limited. Now-a-days EST-SSR markers are preferred to genomic SSR (gSSR) as they represent only the functional part of the genome, which can be easily associated with desired trait. The present study was taken up with a new set of 351 EST-SSRs developed from the 4085 non redundant EST sequences of two Indian sugarcane cultivars. Among these EST-SSRs, TNR containing motifs were predominant with a frequency of 51.6%. Thirty percent EST-SSRs showed homology with annotated protein. A high frequency of SSRs was found in the 5′UTR and in the ORF (about 27%) and a low frequency was observed in the 3′UTR (about 8%). Two hundred twenty-seven EST-SSRs were evaluated, in sugarcane, allied genera of sugarcane and cereals, and 134 of these have revealed polymorphism with a range of PIC value 0.12 to 0.99. The cross transferability rate ranged from 87.0% to 93.4% in Saccharum complex, 80.0% to 87.0% in allied genera, and 76.0% to 80.0% in cereals. Cloning and sequencing of EST-SSR size variant amplicons revealed that the variation in the number of repeat-units was the main source of EST-SSR fragment polymorphism. When 124 sugarcane accessions were analyzed for population structure using model-based approach, seven genetically distinct groups or admixtures thereof were observed in sugarcane. Results of principal coordinate analysis or UPGMA to evaluate genetic relationships delineated also the 124 accessions into seven groups. Thus, a high level of polymorphism adequate genetic diversity and population structure assayed with the EST-SSR markers not only suggested their utility in various applications in genetics and genomics in sugarcane but also enriched the microsatellite marker resources in sugarcane.  相似文献   
973.
The camel seminal plasma contains a diverse array of components including lipids, carbohydrates, peptides, ions and proteins. These are essential for maintaining normal physiology of spermatozoa and are secreted mainly from the prostrate, epidydimis and bulbo-urethral glands of reproductive system. The protein profiles of camel seminal plasma were resolved by two-dimensional gel electrophoresis (2D-PAGE). The majority of the protein was found in acidic regions below pI 7.0 and the 19 brightly stained proteins were identified by MALDI-TOF/MS analysis. On the basis of proteomic profiles, β-nerve growth factor (β-NGF) was purified by ion-exchange and gel filtration chromatography and identified by SDS-PAGE and MALDI-TOF/MS analysis. It was further confirmed by western blotting experiments using rabbit anti-β-NGF primary antibody.  相似文献   
974.
975.
Actions taking place in the environment are critical for our survival. We review evidence on attention to action, drawing on sets of converging evidence from neuropsychological patients through to studies of the time course and neural locus of action-based cueing of attention in normal observers. We show that the presence of action relations between stimuli helps reduce visual extinction in patients with limited attention to the contralesional side of space, while the first saccades made by normal observers and early perceptual and attentional responses measured using electroencephalography/event-related potentials are modulated by preparation of action and by seeing objects being grasped correctly or incorrectly for action. With both normal observers and patients, there is evidence for two components to these effects based on both visual perceptual and motor-based responses. While the perceptual responses reflect factors such as the visual familiarity of the action-related information, the motor response component is determined by factors such as the alignment of the objects with the observer''s effectors and not by the visual familiarity of the stimuli. In addition to this, we suggest that action relations between stimuli can be coded pre-attentively, in the absence of attention to the stimulus, and action relations cue perceptual and motor responses rapidly and automatically. At present, formal theories of visual attention are not set up to account for these action-related effects; we suggest ways that theories could be expected to enable action effects to be incorporated.  相似文献   
976.
Purified α-amylase from a soil bacterium Bacillus sp. SKB4 was immobilized on coconut coir, an inexpensive cellulosic fiber, with the cross-linking agent glutaraldehyde. The catalytic properties and stability of the immobilized enzyme were compared with those of its soluble form. The enzyme retained 97.2% of its activity and its catalytic properties were not drastically altered after immobilization. The pH optimum and stability of the immobilized enzyme were shifted towards the alkaline range compared to the free enzyme. The optimum temperature for enzymatic activity was 90°C in both forms of the enzyme. The soluble and immobilized enzyme retained 19% and 70% of original activity, respectively, after pre-incubation for 1 h at 90°C. Immobilized amylase was less susceptible to attack by heavy metal ions and showed higher Km and Vmax values than its free form. The bound enzyme showed significant activity and stability after 6 months of storage at 4°C. All of these characteristics make the new carrier system suitable for use in the bioprocess and food industries.  相似文献   
977.
A number of studies have been carried out to examine the biological function of conjugated linoleic acid (CLA) and its potential health benefits. However, not much is known about how CLA isomers mediate their effect on angiogenesis and vascularization during early placentation. In this paper we demonstrate that cis-9,trans-11(c9,t11)-CLA stimulated the expression of angiopoietin like-4 (ANGPTL4) mRNA and protein accompanied by tube formation in first trimester placental trophoblast cells, HTR8/SVneo whereas the other CLA isomer, trans-10,cis-12 (t10,c12)-CLA had no such effects. c9,t11-CLA however did not stimulate expression of the most potent angiogenic factor, vascular endothelial growth factor (VEGF) in these cells. Silencing ANGPTL4 in these cells significantly reduced the stimulatory effect of c9,t11-CLA on tube formation, indicating the involvement of ANGPTL4. In addition, c9,t11-CLA increased the mRNA expression of several pro-angiogenic factors such as fatty acid binding protein-4 (FABP4), cyclooxygenase-2 (COX-2) and adipose differentiation-related protein (ADRP) in HTR8/SVneo cells. c9,t11-CLA also induced the uptake of docosahexaenoic acid, 22:6n − 3 (DHA), a stimulator of tube formation in these cells. Triacsin C, an acylCoA synthetase inhibitor, attenuated c9,t11-CLA induced DHA uptake, tube formation and cellular proliferation in HTR8/SVneo cells.  相似文献   
978.
Specific interactions of growth factors with heparan sulfate may function as "switches" to regulate stages of branching morphogenesis in developing mammalian organs, such as breast, lung, salivary gland and kidney, but the evidence derives mostly from studies of explanted tissues or cell culture (Shah et al., 2004). We recently provided in vivo evidence that inactivation of Ndst1, the predominant N-deacetylase/N-sulfotransferase gene essential for the formation of mature heparan sulfate, results in a highly specific defect in murine lobuloalveolar development (Crawford et al., 2010). Here, we demonstrate a highly penetrant dramatic defect in primary branching by mammary epithelial-specific inactivation of Ext1, a subunit of the copolymerase complex that catalyzes the formation of the heparan sulfate chain. In contrast to Ext1 deletion, inactivation of Hs2st (which encodes an enzyme required for 2-O-sulfation of uronic acids in heparan sulfate) did not inhibit ductal formation but displayed markedly decreased secondary and ductal side-branches as well as fewer bifurcated terminal end buds. Targeted conditional deletion of c-Met, the receptor for HGF, in mammary epithelial cells showed similar defects in secondary and ductal side-branching, but did not result in any apparent defect in bifurcation of terminal end buds. Although there is published evidence indicating a role for 2-O sulfation in HGF binding, primary epithelial cells isolated from Hs2st conditional deletions were able to activate Erk in the presence of HGF and there appeared to be only a slight reduction in HGF-mediated c-Met phosphorylation in these cells compared to control. Thus, both c-Met and Hs2st play important, but partly independent, roles in secondary and ductal side-branching. When considered together with previous studies of Ndst1-deficient glands, the data presented here raise the possibility of partially-independent regulation by heparan sulfate-dependent pathways of primary ductal branching, terminal end bud bifurcation, secondary branching, ductal side-branching and lobuloalveolar formation.  相似文献   
979.
Invadopodia are dynamic actin structures at the cell surface that degrade extracellular matrix and act as sites of signal transduction. The biogenesis of invadopodia, including the mechanisms regulating their formation, composition, and turnover is not entirely understood. Here, we demonstrate that antibody ligation of ADAM12, a transmembrane disintegrin and metalloprotease, resulted in the rapid accumulation of invadopodia with extracellular matrix-degrading capacity in epithelial cells expressing the αvβ3 integrin and active c-Src kinase. The induction of invadopodia clusters required an intact c-Src interaction site in the ADAM12 cytoplasmic domain, but was independent of the catalytic activity of ADAM12. Caveolin-1 and transmembrane protease MMP14/MT1-MMP were both present in the ADAM12-induced clusters of invadopodia, and cholesterol depletion prevented their formation, suggesting that lipid-raft microdomains are involved in the process. Importantly, our data demonstrate that ADAM12-mediated ectodomain shedding of epidermal growth factor receptor ligands can occur within these invadopodia. Such localized growth factor signalling offers an interesting novel biological concept highly relevant to the properties of carcinoma cells, which often show upregulated ADAM12 and β3 integrin expression, together with high levels of c-Src kinase activity.  相似文献   
980.
Aberrant production of IL-21 by T cells is critical for the development of type 1 diabetes (T1D) in NOD mice. The pathogenic effects of IL-21 are partly due to its ability to promote the generation of T(H)-17 cells. Interferon Regulatory Factor (IRF4) is a crucial regulator of IL-17 and IL-21 production. We recently found that the serine-threonine kinase ROCK2 phosphorylates IRF4 and regulates its ability to control IL-17 and IL-21 production. Here we show that NOD T cells aberrantly activate ROCK2. We furthermore demonstrate that ROCK inhibition corrects the abnormal IRF4 function in NOD T cells and diminishes their production of IL-17 and IL-21. Importantly, administration of a ROCK inhibitor to NOD mice protects against diabetes development. These studies thus support the idea that ROCK2 is inappropriately activated in NOD T cells and that ROCK kinases could represent important therapeutic targets for the treatment of T1D.  相似文献   
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