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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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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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Cutaneous T-cell lymphoma   总被引:1,自引:0,他引:1  
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Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Um die Ausbreitung von SARS-CoV‑2 (schweres akutes Atemwegssyndrom-Coronavirus-Typ&nbsp;2) zu verlangsamen, haben Bund...  相似文献   
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The policy and health service background to this discussion are the radical changes in cancer services currently underway in the wake of the Calman-Hine Report and the wider changes ushered in by the NHS and Community Care Act 1990 (UK). Using the changing face of hospice care as the focus, the authors explore some of the potential issues and dilemmas involved in providing supportive care for cancer patients and their families. Three 'themes', or areas of concern, are highlighted: links between services, changing organizational factors, and increasing 'medical imperialism'. Potential benefits and drawbacks of the changing ethos and organizational structures are discussed. Interview data are used as 'triggers' for the presentation of the authors' own reflections on developments in the hospice and cancer services' arenas. The paper draws on interview data collected in the pilot phase of a 3-year study on the psycho-social needs of cancer patients and their informal carers in north-west England. Twenty-nine interviews were conducted with a range of professionals involved in the provision of cancer services in Lancaster and Kendal. In the spirit of 'gathering thoughts' and facilitating debate, a commentary on developments in the hospice sector is offered rather than any firm conclusion.  相似文献   
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Intracardiac tuberculomas are extremely rare, and cardiac involvement in tuberculosis accounts for only 0.5% of extrapulmonary tuberculosis. We report for the first time incremental value of live/real time three‐dimensional transesophageal echocardiography over two‐dimensional transesophageal echocardiography in the assessment of a tuberculoma involving the left atrium and left atrial appendage.  相似文献   
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