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We sought to assess the effect of an increase in cAMP on sodium channels on adult rat cardiac ventricular myocytes. Sodium channels were studied with the use of the radiolabeled sodium channel-specific toxin [3H] batrachotoxinin benzoate ([3H]BTXB). Forskolin, isoproterenol, prostaglandin E1, cholera toxin, and pertussis toxin each increased cAMP levels and decreased the number of [3H]BTXB binding sites without changing the affinity of [3H]BTXB for the sodium channel. The cAMP analog 8-bromo-cyclic AMP (8-Br-cAMP) reduced the number of [3H]BTXB binding sites from 19 fmol/10(5) cells to 11 fmol/10(5) cells. [3H]BTXB binding site down-regulation was reversible, cAMP dose-dependent, and time-dependent. To test the hypothesis that the cAMP effect was mediated by cAMP-dependent phosphorylation, we determined the effect of 8-Br-cAMP on [3H]BTXB binding after preincubation of myocytes with N-(2-(methylamino)ethyl)-5-isoquinolinesulfonamide dihydrochloride (H8), a protein kinase A inhibitor. H8 inhibited 70% of the decrease in the number of [3H]BTXB binding sites induced by 8-Br-cAMP. Thus increases in intracellular cAMP in cardiac myocytes reversibly induced a decrease in the number of [3H]BTXB binding sites via cAMP-dependent protein phosphorylation, possibly of the sodium channel.  相似文献   
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At the core of his political rhetoric, Donald Trump speaks about work: the experience of laboring, the agonies of the labor market, and the future of employment. This article considers how the anthropology of work can contribute to an analysis of the political moment. Many commentators, including Trump himself, have interpreted a vote for Trump as an act of labor nostalgia, a gesture of yearning for an industrial past. Such commentary describes Trump voters by describing the jobs that many of them once did—manufacturing jobs. But what if, instead, we considered the jobs that many Trump voters now do, that is, service jobs? What if Trump’s discourse, with its themes of domination and submission, offers an incisive response to the intimacies of power as lived by restaurant workers and customer service representatives? Could the election come into focus as an uprising in the service sector? This article takes two steps. First, it engages with literature from sociology and economics in order to point towards a crucial transformation in the US workplace since the 2008 financial crisis: the ascendancy of monopolistic corporations that defy the neoliberal model. Second, the article explores new developments in the service sector by assessing the work experience of Uber drivers. Trump’s rhetoric can be interpreted as a response to the 2008 crisis and the novel modes of service work that the crisis made possible—including Uber. As it faces the political consequences of today’s toil, the anthropology of work gains a new research agenda.  相似文献   
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Seedlings of Maranthes corymbosa (Blume) and Eucalyptus tetrodonta(F. Muell) were grown with or without CO2 enrichment (700µmolCO2 mol–1 The response of stomatal conductance (g2) toleaf drying, exogenous absclslc acid and calcium ions was investigatedin M. corymbosa. Reciprocal transfer experiments were also conductedwhereby plants were grown in one treatment and then transferredto the other before g, was measured. Stomatal conductance in M. corymbosa was more sensitive (a greaterpercentage decline in g2 per unit percentage decline in leaffresh weight) to leaf water status under conditions of CO2 enrichmentcompared to ambient conditions. However, the rate of reductionof g2 in response to exogenous abscisic acid was not influencedby CO2 treatment. In contrast, the rate of reduction of g2,in response to exogenous CaCl2 was decreased under conditionsof CO2 enrichment. Reciprocal transfer experiments showed that expo sure to CO2enrichment results in a short-term, reversible decline in g2,as a result of decreased stomatal aperture and a long-term,irreversible decline in g2 as a result of a decreased stomataldensity. Seedlings of E. tetrodonta were used to investigate the responseof g2 to light flux density, leaf-to-air vapour pressure difference(LAVPD), leaf internal CO2 concentration (C1 and temperature.Reciprocal transfer experiments were also conducted. CO2 enrichmentdid not influence the pattern or sensitivity of response ofg to LAVPD and C in E. tetrodonta. In contrast, the slope ofthe response of g2, to temperature decreased for trees grownunder elevated [CO2]a conditions and the equilibrium g2 attainedat saturating light was also decreased for plants grown underelevated [CO2a. conditions. Key words: Stomata, elevated CO2, tropical trees  相似文献   
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C-reactive protein levels are influenced by common IL-1 gene variations   总被引:15,自引:0,他引:15  
Elevated markers of systemic inflammation are associated with the development of acute coronary syndromes, but there is no current explanation for increased inflammation in overtly healthy individuals. The influence of genetic control of the inflammatory response on the observed variability is unknown. We studied the frequency of four polymorphisms in interleukin (IL) 1 genes, known to modulate inflammation, in 454 individuals undergoing coronary angiography and analysed their influence on plasma C-reactive protein (CRP) and fibrinogen levels. Females and smokers had higher levels of CRP than males (Pi = 0.001) and non-smokers (Pi = 0.001). Patients with genotype 2.2 for the IL-1B(+3954) polymorphism had twice the median CRP levels of patients who were genotype 1.1 (4.33 vs 2.01 mg/l; P = 0.001). Patients with genotype 1.2 or 2.2 at the IL-1A(+4845) polymorphism also had higher median CRP (2.92 vs 2.05 mg/l, Pi = 0.023). In multivariate analyses, CRP levels remained significantly associated with IL-1 polymorphisms after adjustment for smoking, gender and age. Fibrinogen levels had similar associations with the IL-1 genotypes. These data indicate that IL-1 gene polymorphisms known to affect the inflammatory response are highly related to plasma levels of CRP and fibrinogen in patients referred for coronary angiography.  相似文献   
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International Journal of Primatology - When studying animal behavior in the wild, some behaviors may require observation from a relatively short distance. In these cases, habituation is commonly...  相似文献   
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D Grant  C Stiller  J Duff  N McKenzie  W Wall  P Keown  C Ghent  W Kostuk  J Kutt  J Chin  et al. 《CMAJ》1986,135(3):197-203
Organ transplantation has become the treatment of choice for selected patients with end-stage failure of the heart, liver or kidneys. The expanding role for organ transplantation, however, has led to a corresponding increase in the complexity of patient management. In response to these changes, University Hospital, London, Ont., has established an interdisciplinary multi-organ transplant service (MOTS). MOTS coordinates donor organ procurement and patient management. Donor organs have been retrieved from as far south as Dalton, Georgia, as far west as Calgary and as far east as Halifax. As of Dec. 31, 1985, 485 transplants had been performed, including 387 kidney transplants, 51 heart transplants, 3 heart/lung transplants, 43 liver transplants (in adults and children) and 1 pancreas transplant. With current immunosuppressive protocols MOTS projects 1-year patient survival rates of 95% after kidney transplantation, 88% after heart transplantation and 81% after liver transplantation. Patient rehabilitation has been excellent.  相似文献   
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