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Neurohydatidosis     
Early and non‐invasive evaluation of hydatid infestation of brain and spine is of paramount importance, especially in endemic areas. We present a spectrum of imaging findings in neurohydatidosis with a brief review of literature.  相似文献   
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OBJECTIVE: Chronic hypertension is associated with an increased risk for tissue injury that may be mediated in part by endothelium and inflammatory cells. To clarify a possible underlying mechanisms, we examined leukocyte migration in the microcirculation and concomitant parenchymal cell death. METHODS: The mesentery of spontaneously hypertensive rats (SHRs) and their normotensive controls, Wistar Kyoto (WKY) rats, was examined with digital fluorescence microscopy after topical stimulation with an inflammatory mediator (f-met-leu-phe, 10(-8)M). The migratory pathways of individual leukocytes were traced, and at the same time cell death was detected by use of a life-death indicator (propidium iodide) over a period of 3 hours. RESULTS: Both WKY and SHR had a progressively increasing number of leukocytes migrating across the endothelium in postcapillary venules into the tissue parenchyma. But parenchymal cell death was detected in a random pattern in the mesentery tissue, without correlation to the migratory positions of the leukocytes. Although mature SHR rats (about 17 weeks) exhibited the same level of cell death as age-matched WKY rats, older WKY rats (about 30 weeks) had significantly lower levels of cell death, whereas the SHR rats maintained the same number of parenchymal cell death as mature animals. CONCLUSIONS: These results suggest that in the presence of an inflammatory mediator, the SHR may exhibit a stronger response to an inflammatory mediator than normotensive WKY rats in a fashion that is age, but not blood pressure, dependent. Parenchymal cell death does not correlate with migration of activated leukocytes at the microvascular level.  相似文献   
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Mucormycosis is a rare fungal infection of childhood, occurring mainly in patients with chronic illnesses such as diabetes and malignancies. The fungus seldom grows in culture and confirmation of the diagnosis depends on histologic examination of infected tissues. To date, the reported natural history of the disease has been rapid progression and a fatal outcome. Therefore, the importance of early diagnosis by tissue biopsy and early treatment with surgical debridement and systemic antifungal therapy cannot be overemphasized. The pulmonary system is the most common site for mucormycosis in patients with leukemia. We report what we believe to be the first successfully treated case of isolated muscular mucormycosis occurring in a child with biphenotypic acute leukemia. The diagnosis was made promptly by tissue examination at the time of surgical debridement. The patient was also given systemic amphotericin-B therapy.   相似文献   
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Roxatidine acetate, a new H2 receptor antagonist, was compared with ranitidine in the treatment of duodenal ulcers in a double-blind multicentre study. Eighty-four patients with endoscopically proven duodenal ulcer were randomized to receive 150 mg roxatidine acetate or 300 mg ranitidine at bedtime. Repeat endoscopy was performed after 4 weeks (25–33 days) and if the ulcer had not healed, another endoscopy was performed after a further 4 weeks of treatment. Using per protocol analysis 73.6% of ulcers treated with roxatidine healed at 4 weeks compared to 72.2% of ulcers treated with ranitidine (P=NS). The healing rates at 8 weeks were 92% with roxatidine and 83.3% with ranitidine (P=NS). Using equivalence tests, the healing rate of roxatidine was found to be equivalent to that of ranitidine within a 20% region. Roxatidine users took significantly less antacids than ranitidine users (P < 0.05). There were no significant adverse effects due to roxatidine or ranitidine. Roxatidine is a safe effective drug in the treatment of duodenal ulcers with a healing rate comparable to that of ranitidine.  相似文献   
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BaCKGROUND: Due to the aging general population, deceased donors > or =55 years will form an increasingly larger proportion of the deceased kidney donor pool. METHODS: Using data from the United States Renal Data System, we determined the change in graft survival between 1996 and 2000 among 32,557 recipients of donors aged <55 years and > or =55 years in univariate and multivariate survival analyses. We identified donor risk factors for graft loss that might influence the decision to accept or reject donors <55 and > or =55 years. The initial glomerular filtration rate established 6 months after transplantation (initial GFR), and the stability of GFR in the first post-transplant year (GFR at 12 months post-transplantation-GFR at six months post-transplantation) were compared between recipients of donors <55 and > or =55 years and the association of these factors with graft survival was determined. RESULTS: In 2000, one-year graft survival in donors > or =55 years was 86.7%. Between 1996 and 1999 the projected graft half life improved from 11.4 to 14.5 years for recipients of donors <55 years (P < 0.01); however, there was no improvement for recipients of donors > or =55 years (8.2 to 9.2 year, P= 0.46). Among donor factors studied, only cold ischemic time >24 hours identified recipients of donors > or =55 years at risk for graft loss. Compared to recipients of donors <55 years, recipients of donors > or =55 years established a lower initial GFR (42 vs. 56 mL/min/1.73 m(2), P < 0.0001), and had less stable GFR in the first post-transplant year (-1.5 vs. -0.6 mL/min/1.73 m(2), P <.0001). Recipients from donors > or =55 years with initial GFR > or =50 mL/min/1.73 m(2) and no drop GFR during the first post-transplant year had graft survival that was superior to that of donors <55 years with either initial GFR <50 mL/min/1.73 m(2) or a drop in GFR during the first post-transplant year. CONCLUSION: Donors > or =55 years are a valuable resource. Despite improvements in immunosuppression, rejection, and delayed graft function, the projected increase in long-term graft survival among recipients of donors <55 years was not shared among recipients of donors > or =55 years. Recipients of donors > or =55 years had lower initial GFR, and less stable GFR during the first post-transplant year. Limiting cold ischemic time to <24 hours may improve outcomes among recipients of donors > or =55 years. Future studies to maximize initial GFR and minimize early loss of GFR in recipients of donors > or =55 years may lead to improved outcomes from deceased donors > or =55 years.  相似文献   
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