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The etiology of neuronal intestinal dysplasia remains largely unknown. There is, however, supporting evidence of the existence of Hirschprung's disease or chronic intestinal obstruction associated with neuronal intestinal dysplasia. With the aim of investigating the possible development of neuronal intestinal dysplasia linked to chronic intestinal obstruction, we have examined the enteric nervous system response to long-term obstruction in a rat model. Three different surgical techniques were tested in Wistar male rats. In animals that survived longer than the cutoff chronic intestinal obstruction point (6 weeks), full-thickness biopsies and acetylcholinesterase (AChE), NADH, hematoxylin-eosin, and anti-S100 protein stainings were performed. The results of our model indicate that chronic intestinal obstruction induced different degrees of enteric nervous system dysplasia, including histological features of neuronal intestinal dysplasia. The relationship between chronic intestinal obstruction and anomalies of the enteric nervous system, including neuronal intestinal dysplasia, needs to be further studied.  相似文献   
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Abstract  The general expectation that patients should be willing to trust nurses is rarely explored or challenged despite claims of diminishing public trust in social and professional institutions. Everyday meanings of trust take account of circumstance and suggest that our understanding of what it means to trust is contextually bound. However, in the context of health care, to trust implies a particular understanding which becomes apparent when abuses of this trust are reported and acknowledged as scandals. The predominant assumption in the literature that trust is something that occurs between equally competent adults cannot explain trust in nursing precisely because of the unequal power relationships between patients on the one hand and healthcare professionals on the other. Moreover, the tendency to conflate terms such as trust, reliance, confidence and so on suggests that confusion permeates discussions of trust in nursing. In this paper, I argue in support of Annette Baier's requirement of good will (or lack of ill will) as the essential feature of trust, and outline how this account (i) enables us to make the necessary distinctions between trust on the one hand and 'trust pretenders' on the other; and (ii) lays the foundations for understanding trust in relationships, such as those between patients and nurses, where power differentials exist.  相似文献   
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OBJECTIVE: The studies showing the superior characteristics of ITA graft and its impact on the clinical results of coronary artery surgery were performed with ITA harvested almost exclusively as a pedicle. This study assesses the impact of ITA skeletonization on its innervation and reactivity. METHODS: Segments of skeletonized and non-skeletonized ITA were stained with antibodies against protein S-100 to look for the presence of sympathetic nerve fibers. The functional studies were performed on segments of discarded human pedicled ITA that were divided into two 3mm rings, one skeletonized and another non-skeletonized. We compared concentration-effect relationships for the contraction to norepinephrine and endothelium-dependent relaxation to acetylcholine and bradykinin, as well as endothelium-independent relaxation to sodium nitroprusside in skeletonized and non-skeletonized segments of the same ITA. RESULTS: Skeletonized ITA was devoid of protein S-100 positive nerve fibers. It contracted stronger (maximal response 37.0+/-2.04 vs. 25.4+/-1.83mN (P<0.001)) and was twice as sensitive to norepinephrine: pD(2) 6.03+/-0.10 vs. 5.70+/-0.12 (P=0.035). The endothelium-dependent relaxation responses did not differ between skeletonized and non-skeletonized ITA rings. The skeletonized ITA rings appeared over 10 times more sensitive to sodium nitroprusside: pD(2) 6.66+/-0.20 vs. 5.59+/-0.37 (P=0.012)-potency ratio 11.61. The maximal responses did not differ significantly: 112.0+/-6.71 vs. 129.4+/-16.4% (P=0.33). CONCLUSIONS: Skeletonization results in sympathectomy of ITA. It has no effect on endothelium-dependent relaxation but increases reactivity of ITA to norepinephrine. This augmented response to alpha-agonist is small, in comparison with over a ten-fold increase in sensitivity to sodium nitroprusside. Pedicled and skeletonized ITA are functionally significantly different vessels when studied in vitro.  相似文献   
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Aim To elicit nurses' accounts of their involvement with nursing research and their interpretations of the meaning of these projects for their practice.
Background The links between research and practice development in health care are poorly understood and require further exploration in the light of the emerging research and development agenda within the National Health Service.
Methods Semi-structured interviews were conducted with 15 qualified nurses working on a Nursing Development Unit. The interviews were tape recorded, transcribed and analysed thematically.
Findings Data analysis identified two distinct groups—a core group of nurses actively engaged in the research projects and a peripheral group involved in data collection. The characteristics of the core group mirror the characteristics of those involved in non-research-based practice development activities.
Conclusions Engaging in research activities does not always result in the development of practice, however, there appears to be a link between practice development and critical thinking.  相似文献   
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Cutaneous T-cell lymphoma   总被引:1,自引:0,他引:1  
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BACKGROUND: Allergy to plant-derived foods is associated with birch pollinosis in central and northern Europe. Symptoms elicited are usually limited to the oropharyngeal system. By contrast, in the Mediterranean area, allergy to the same foods manifests more frequently with systemic reactions caused by nonspecific lipid transfer proteins (nsLTP), independently of an associated pollinosis. OBJECTIVE: We sought to investigate the pattern of immunoglobulin E (IgE) binding protein bands implicated in lettuce allergy, in particular the presence of an nsLTP. METHODS: Consecutive lettuce allergic patients were selected. Determination of serum-specific IgE, immunoblot, and inhibition experiments were performed in order to study the pattern of IgE binding proteins and the potential cross-reactivity to pollens. Inhibition studies with recombinant allergens were conducted to identify the lettuce allergens. The major allergen was subjected to N-terminal amino acid sequencing. RESULTS: Fourteen patients were diagnosed as being allergic to lettuce. All were sensitized to Platanus pollen. Ten of them showed specific IgE to a lettuce protein of 9-kDa. The IgE binding to this protein was completely inhibited by the cherry-LTP and peach extract. The N-terminal sequence of the 9-kDa protein showed a high degree of amino acid sequence identity to other nsLTPs. A clear partial cross-reactivity was observed between lettuce-LTP and Platanus-pollen extract. CONCLUSIONS: An LTP has been demonstrated to be a major allergen in patients suffering from lettuce allergy.  相似文献   
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