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Stevens' question "Who Gets Care?" is in the tradition of those arguing for increased access and a more equitable distribution of society's benefits. As such, it provides a framework for nursing scholarship concerned with social as contrasted with individual interventions. Nursing's Agenda for Health Care Reform advances the argument still further by questioning the ideology reinforced by the current system, and offering an alternative system, alternative services and agents. In so doing, the proposed agenda questions the dominant ideology and is, therefore, more accurately a radical departure from the status quo than a reform. While there are some implicit assumptions of both reform and radical change embedded within the work of those addressing a "curriculum revolution," the discussion would benefit from explicit expositions of both the social construction and social function of higher education.  相似文献   
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Platelet release by megakaryocytes is regulated by a concert of environmental and autocrine factors. We previously showed that constitutively released adenosine diphosphate by human megakaryocytes leads to platelet production. Here we show that adenosine diphosphate elicits, in human megakaryocytes, an increase in cytosolic calcium concentration, followed by a plateau, which is lowered in the absence of extracellular calcium, suggesting the involvement of Store-Operated Calcium Entry. Indeed, we demonstrate that megakaryocytes express the major candidates to mediate Store-Operated Calcium Entry, stromal interaction molecule 1, Orai1 and canonical transient receptor potential 1, which are activated upon either pharmacological or physiological depletion of the intracellular calcium pool. This mechanism is inhibited by phospholipase C or inositol-3-phosphate receptor inhibitors and by a specific calcium entry blocker. Studies on megakaryocyte behavior, on extracellular matrix proteins that support proplatelet extension, show that calcium mobilization from intracellular stores activates signaling cascades that trigger megakaryocyte adhesion and proplatelet formation, and promotes extracellular calcium entry which is primarily involved in the regulation of the contractile force responsible for megakaryocyte motility. These findings provide the first evidence that both calcium mobilization from intracellular stores and extracellular calcium entry specifically regulate human megakaryocyte functions.  相似文献   
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The patch-clamp technique was used to investigate the electrical response of cardiac microvascular endothelial cells to fluid stream applied through a microtube. The fluid stream induced a membrane current whose amplitude was dependent on flow rate. The I-V relationship of the flow-activated current showed a strong inward rectification and a reversal potential close to +30 mV, which gave a P(Na)/P(k)=3.47. The inward and outward components of the current nearly disappeared when extracellular Na(+)and internal K(+), respectively, were replaced by NMDG(+). Finally, the flow-activated current was fully blocked by 50 microM Gd(3+)and La(3+). These results show that cardiac microvascular endothelial cells respond to mechanical stimulation associated with flow by increasing their permeability to Na(+)and K(+). This mechanism is suggested to contribute to ionic homeostasis at high heart rates and during post-ischaemic reperfusion.  相似文献   
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BackgroundA relation between the side of motor onset and cognitive impairment in early PD has been reported, suggesting that the asymmetric degeneration affecting subcortical regions may play a pivotal role in lateralized cognitive function. However, evidences are controversial and all previous studies were performed on treated patients, though it is known that dopaminergic therapy can affect cognition in PD.MethodsSixty-nine early untreated PD patients underwent an extensive neuropsychological battery exploring memory, visuospatial and attention/executive functions. Patients were divided with respect of the side of onset (right vs. left) and further grouped according to motor phenotype (tremor vs. rigidity-bradykinesia). Multivariate analysis of variance has been carried out to compare clinical and neuropsychological data between subgroups.ResultsThere were no differences in any neuropsychological task between right-sided and left-sided onset subgroups, irrespective of tremor dominant or rigid-bradykinetic phenotype. Age at onset was significantly higher in patients with any cognitive impairment as compared with patients without (66.7 ± 3.2 vs. 56.3 ± 6.8 years, p = 0.001).ConclusionSide of motor onset is not a major determinant for developing lateralized cognitive deficits in newly diagnosed untreated PD patients.  相似文献   
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Summary The effect of cimetidine, an inhibitor of suppressor T lymphocytes, on the burst-promiting activity (BPA) of normal T lymphocytes has been studied. Cimetidine has been shown to increase the BPA of normal T lymphocytes, both when added to the culture and when T lymphocytes were preincubated for 1 h with it. Cimetidine had no direct effect on the in vitro growth of burstforming units (BFU-E). Our results show that CD 8 suppressor T lymphocytes inhibit the in vitro growth of BFU-E in normal conditions, either directly or through inhibition of BPA of CD 4 helper T lymphocytes. Cimetidine has proved to be a useful tool for investigating the hematological role of T-lymphocyte subsets in normal and pathological conditions.This work was supported by a grant of theMinistem delta Ricerca Scientifica e Tecnologica, Italy  相似文献   
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