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1.
Limbic hyperactivation and an impaired functional interplay between the amygdala and the prefrontal cortex are discussed to go along with, or even cause, pathological anxiety. Within the multi-faceted group of anxiety disorders, the highly prevalent social phobia (SP) is characterized by excessive fear of being negatively evaluated. Although there is widespread evidence for amygdala hypersensitivity to emotional faces in SP, verbal material has rarely been used in imaging studies, in particular with an eye on disorder-specificity. Using functional magnetic resonance imaging (fMRI) and a block design consisting of (1) overall negative, (2) social-phobia related, (3) positive, and (4) neutral words, we studied 25 female patients with social phobia and 25 healthy female control subjects (HC). Results demonstrated amygdala hyperactivation to disorder-relevant but not to generally negative words in SP patients, with a positive correlation to symptom severity. A functional connectivity analysis revealed a weaker coupling between the amygdala and the left middle frontal gyrus in patients. Symptom severity was negatively related to connectivity strength between the amygdala and the ventromedial prefrontal and orbitofrontal cortex (Brodmann Area 10 and 11). The findings clearly support the view of a hypersensitive threat-detection system, combined with disorder-related alterations in amygdala-prefrontal cortex connectivity in pathological anxiety.  相似文献   

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Chronic oral anticoagulant treatment is obligatory in patients (class I) with mechanical heart valves and in patients with atrial fibrillation with CHADS2 score >1. When these patients undergo percutaneous coronary intervention with placement of a stent, there is also an indication for treatment with aspirin and clopidogrel. Unfortunately, triple therapy is known to increase the bleeding risk. For this group of patients, the bottom line is to find the ideal therapy in patients with indications for both chronic anticoagulation therapy and percutaneous intervention to prevent thromboembolic complications such as stent thrombosis without increasing the risk of bleeding. (Neth Heart J 2010;18:444-50.)  相似文献   

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In this short response to Loïc Wacquant's ‘Marginality, Ethnicity and Penality in the Neo-liberal City’, I outline two intellectual conversations that emerge from the author's work. The first develops out of the connections that the author draws between systems of criminal justice and welfare. The second grows out of the disassociation he urges us to see between the logics and trajectories of crime, on the one hand, and criminal justice on the other. I then briefly describe how my own work has been influenced by and contributes to these two ongoing streams of research.  相似文献   

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The objective of this paper is the structural and narrative reconstruction of representations of ‘nature’, ‘wildlife’ and ‘landscape’, held by rural residents of the Dadia Forest Reserve. Data collection involved in-depth interviews. Employing a social representations’ approach, we recovered representational elements that are expected in the case of rural belief systems, such as negative dispositions towards wolves and foxes, as well as elements of an urban adherence, such as nature’s independence. Representational elements refer to visual aspects of the countryside, which seem compatible with the figurative nucleus of the rural idyll. Concerning ‘wildlife’, residents focused on vultures, which comprise the main tourist attraction of the reserve. Scientific knowledge adds to the complexity of the narrative schema, which corresponds to the representation of ‘wildlife’. Interviewees perceived the rural landscape as an interface between the natural and the human-conditioned environment. Our study shows that interviewees make no reference to environmental conservation or quality of life issues, as it could be expected according to relatively wide definitions of the term ‘environmentalism’. Environmental messages reinforced by ecotourism development seem to be recalled primarily in terms of their compatibility with the perceived economic benefit of local people. Despite ecotourism development, representational elements that diverge from a tourist version of ‘nature’, ‘wildlife’ and ‘landscape’ were not pronounced within rural belief-systems. Further interventions within the study area are needed, in order to address a variety of topics under the environmental conservation discourse and raise the environmental awareness of rural residents.  相似文献   

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Summary The nature of the steroids secreted by gonads of fish differs significantly from those of the mammals. The classical teleost steroids, oestradiol, testosterone, 11-ketotestosterone and 17,20P, have been measured in a wide variety of teleosts but do not always reflect biological activities. There is increasing evidence that teleost gonads may produce a number of non-classical steroids which may play an important role in their reproductive biology. Such products include metabolites reduced at C5 to 5 or 5, at C3 to 3 or 3, or hydroxylated at 6-, 7-, or 21. Conjugation, as either glucuronides or sulphates, may contribute either to localization of action within the gonad or to production of pheromones during the immediate pre-spawning period. Although it is often possible only to measure the steroids for which assays are readily available, it is important to recognize that there may be production of steroids that are not detected by such assays, but which nevertheless play a major role in reproductive activity. In evolutionary terms, the teleost hydroxylases probably originated in the very early fishes and show parallels with their analogues in amphibians and mammals. Gene sequencing may reveal a possible common ancestor for all vertebrate 6, 7 and 11-hydroxylases.  相似文献   

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Perchloroethylene (PCE) was tested in a diploid strain (D7) of the yeast Saccharomyces cerevisiae in suspension tests with and without a mammalian microsomal activation system (S9) and ‘in vivo’ by the intrasanguineous host-mediated assay. In addition, enzyme alteration studies were performed in mice non-pretreated or pretreated with phenobarbital + β-naphthoflavone. PCE did not induce any genetic effect either ‘in vitro’ or ‘in vivo’. In the suspension test, PCE was more toxic without metabolic activation and less toxic with mammalian microsomal activation. The enzymatic determinations showed an increase of the aminopyrine demethylase activity and of the level of cytochrome P-450.  相似文献   

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While ‘ethnicity and everyday life’ is a familiar collocation, sociologists concerned with racism and ethnicity have not engaged very much with the extensive body of social theory that takes the ‘everyday’ as its central problematic. In this essay, I consider some of the ways in which the sociology of the everyday might be of use to those concerned with investigating ethnicity and racism. For its part, however, the sociology of the everyday has tended to be remarkably blind to the role played by racism and racialization in the modern world. It is thus no less crucial to consider how the experiences of racialized groups might help us rethink influential accounts of the everyday. To this end, I provide a discussion of pioneering texts by C. L. R. James and W. E. B. du Bois, both of whom were driven by their reflections on racism and resistance to recognize the everyday not as an unremarked context, but as, precisely, a problematic one.  相似文献   

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The Hill reaction, its elucidation, and significance is briefly described. Hill oxidants, the role of the methemoglobin reducing factor and its relation to ferredoxin, and the part played by chloroplast envelopes are discussed. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

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Gabriele Alex 《Ethnos》2013,78(4):523-543
In India, touch is a prime marker of status and social relations. Those who are impure are ‘untouchable’,1 The terms ‘Untouchable’ and ‘Untouchability’ have been abandoned due to the humiliating meaning these terms confer, therefore I use them in inverted commas. The politically correct and common terms today are Scheduled Castes, in short sc, or Dalits, or sometimes Harijan. I use them here synonymously. but those who are of a relatively higher purity are also, depending on the context, either ‘untouchable’ or ‘touchable’ only under certain fixed rules. In this paper, I will explore the contexts in which body contact and touch can be part of personal relations. I describe how these body contacts signify important social relations and establish community identity. Further, I will analyse how patterns of body contact on the one hand change during childhood, and on the other hand produce changes in the status of a social persona. The last point to be investigated is the meaning of touch as a sign for public representations.  相似文献   

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Paalme  Tiina  Kukk  Henn  Kotta  Jonne  Orav  Helen 《Hydrobiologia》2002,(1):469-476
The decomposition of two macroalgal species Cladophora glomerata (CHLOROPHYTA) and Pilayella littoralis (PHAEOPHYTA) was studied in the laboratory and field conditions. These species are known to cause the extensive macroalgal blooms in the whole coastal range of the Baltic Sea. The objective of the experiments was to determine decomposition rates of the macroalgae, follow the changes in tissue nutrient content and validate the role of benthic invertebrates in this process. In the laboratory conditions, the differences in the decomposition rates of the algae were mainly due to the oxygen conditions. The weight loss of C. glomerata was slightly higher in anaerobic conditions than in aerobic conditions. If 99% of initial dry weight of P. littoralis was lost in aerobic conditions then only 20% was lost in anaerobic conditions. In general, the loss of phosphorus and nitrogen in algal tissues followed the weight loss. As an exception, the amount of nitrogen changed very little during the decomposition of C. glomerata. In field conditions, the photosynthetic activity exceeded the decomposition rate of C. glomerata at lower temperatures in spring. The decomposition of P. littoralis was estimated at 49% of its initial dry weight. The addition of benthic invertebrates had no effect on the decomposition process. In summer, the decomposition rates were estimated at 65% for C. glomerata and 68% for P. littoralis being in the same order of magnitude as observed in laboratory conditions. If the decomposition of C. glomerata was faster at the end of the experiment, the most significant losses of weight of P. littoralis took place during the first 2 weeks of deployment. Idotea baltica significantly contributed to the loss of C. glomerata. The decomposition rate of P. littoralis was reduced by the presence of Mytilus edulis and increased by Gammarus oceanicus.  相似文献   

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This overview attempts to cover, from a personal viewpoint, the development of the heparin field during the last four decades. In particular, it emphasizes the metamorphosis of heparan sulfate (HS), from a disturbing contaminant in heparin production to the present-day key player in cell and developmental biology. Our understanding of the structural properties of the polysaccharides has been greatly promoted by studies of their biosynthesis. We now have a fairly detailed view of the various enzymatic reactions, that convert the initial [4GlcA1-4GlcNAc1-]n polymer into sulfated products with highly variable proportions of GlcA/IdoA and of N-acetyl, N-sulfate and O-sulfate substituents. It is also recognized that the variously substituted domains of the polysaccharide serve to interact, in more or less specific fashion, with a multitude of proteins, and that these interactions are essential to the biological functions of the proteins. Molecular genetics has unravelled the gene structures for almost all of the enzymes required to synthesize a heparin or HS chain, and has shown that several of these proteins exhibit genetic polymorphism. While differences in substrate specificity between enzyme isoforms may help to explain the structural variability of, in particular, HS chains, we still only partly understand the key features of heparin/HS biosynthesis and its regulation.  相似文献   

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While racialized youth are often central in debates on citizenship, multiculturalism and belonging, those ascribed as ‘British Chinese’ are constructed as model minorities, lacking a hybridized culture but insulated from racism, and thus invisible in these discussions. This article argues, however, that the model minority discourse is itself a specific form of contemporary racialization that revives ‘yellow peril’ discourses on the capacities of particular ‘Oriental’ bodies. Drawing on ethnographic fieldwork, it examines how young people challenge these constructions, by drawing on popular culture to organize and participate in what they call ‘British Chinese’ and, more provocatively, ‘Oriental’ nightlife spaces. It analyses how through these spaces participants forge a sense of identity that allows them to reimagine themselves as racialized subjects. It demonstrates how these spaces constitute transient sites of experimental belonging, facilitating new cultural politics and social identifications that at once contest reified conceptions of British Chineseness yet also create new exclusions.  相似文献   

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The distribution of Alu-family DNA repeats (AFRs) in chromosomes of phytohaemagglutinin-stimulated peripheral blood lymphocytes of four normal donors and non-stimulated bone marrow cells of four patients with acute leukemia (ALL and ANLL) was studied by in situ hybridization using DNA of recombinant phage lambda containing multiple inserts of AFR as a probe. Over some chromosome bands (14cen, 16p13, 16cen) from normal donors and from leukemic patients clusters of silver grains were detected. Over other three bands (3q26, 8p11-p12 and 14q24) the clusters were found only in chromosomes from the four acute leukemia patients, and were absent from chromosomes of healthy donors. The results suggest non-random long-range distribution of AFRs in human chromosomes, and somatic variations in the distribution of the repeats.  相似文献   

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