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51.
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We report a 15-year-old boy who presented with recurrent headaches associated with numbness, confusion, and speech difficulty. Brain magnetic resonance imaging (MRI) revealed diffuse bilateral white-matter hyperintensity on fluid-attenuated inversion-recovery and T2-weighted images in the internal capsule, periventricular and subcortical white matter, base of the pons, and middle cerebellar peduncles. Lesions were isointense on T1-weighted images and nonenhancing. Muscle biopsy showed changes consistent with a mitochondrial myopathy. Mitochondrial respiratory chain enzyme activity analysis revealed a significant reduction in complex II activity. Genetic testing was negative. We conclude that mitochondrial encephalomyopathy may present with unusual diffuse supratentorial and infratentorial white-matter changes on MRI.  相似文献   
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The aim of this study was to evaluate the effectiveness of a practice magnetic resonance unit, in preparing children to undergo magnetic resonance procedures without general anaesthesia (GA) or sedation. The records of children who attended the practice MRI between February 2002 and April 2004 were retrospectively reviewed. Each record was assessed as to whether the child had passed or failed the practice MRI intervention. Those children who were considered to have passed and were proceeded to a clinical non‐GA MRI had the report of the clinical scan reviewed. If the scan had been reported as non‐diagnostic because of movement artefact it was classified as a failed scan, otherwise it was considered a pass. One hundred and thirty‐four children undertook a practice MRI (age range 4.1–16.1 years, median age 7.7 years, 47% boys) and 120/134 (90%) passed the practice session. In all, 117/120 (98%) subsequently had a clinical non‐GA MRI and 110/117 (94%) passed (median age 7.8 years, 47% boys). Preparation is a safe and effective method to reduce the need for sedation and GA in children undergoing a clinical MRI scan. It provides a positive medical experience for children, parents and staff, and results in cost savings for the hospital.  相似文献   
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After a two week baseline, 209 asthmatic children (mean age 10 years, range 6-17) were randomly allocated to receive 4 mg nedocromil sodium (n = 110) or placebo (n = 99) four times daily for 12 weeks in addition to their current treatment. The children completed daily diary cards and visited the clinic at four week intervals. Statistically significant differences in favour of nedocromil sodium were seen for clinician assessment of asthma severity and diary card symptom scores, pulmonary function and inhaled beta 2 bronchodilator use. Total symptom score decreased by 50% from baseline in the nedocromil sodium group and by 9% in the placebo group during the final four weeks. Nedocromil sodium was considered very or moderately effective by 78% of children/parents (placebo 59%) and 73% of clinicians (placebo 50%). Nausea, headache and sleepiness, and dyspnoea led to withdrawal of one child from nedocromil sodium and placebo treatments, respectively. Reports of sore throat and headache were marginally greater with the nedocromil sodium treatment. It is concluded that nedocromil sodium was both effective and safe in the treatment of asthma in children.  相似文献   
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del Giglio A  Soares HP  Caparroz C  Castro PC 《Cancer》2000,89(11):2301-2308
BACKGROUND: The introduction of serotonin antagonists as antiemetics for prophylaxis of chemotherapy-induced nausea and vomiting represented a major step toward better patient tolerance and adherence to this type of treatment. Several published trials compared different serotonin antagonists without demonstrating clear superiority of any one of them. Because most of these trials compared ondansetron with granisetron, the authors conducted a meta-analysis to determine if the current data available show any therapeutic difference between them. METHODS: MEDLINE and CANCERLIT databases were searched from 1990 to May 1999, and pertinent article references also were surveyed, without restriction to English language. The authors included all randomized controlled trials (RCTs) that had more than 25 patients per arm and compared ondansetron to granisetron for prophylaxis of acute (A) (< 24 hours) and delayed (D) (> 24 hours) nausea (N) and vomiting (V) induced by highly (H) or moderately (M) emetogenic chemotherapy. Only the first chemotherapy cycle was considered for studies that involved a crossover design. RESULTS: Fourteen studies with 6467 evaluable patients among the 21 studies retrieved were selected for this meta-analysis. In none of the eight scenarios studied (AHV, AHN, AMV, AMN, DHV, DHN, DMV, and DMN) could the authors detect any significant differences in the antiemetic efficacy of any of these medications. CONCLUSIONS: The authors conclude that both granisetron and ondansetron have similar antiemetic efficacy for prophylaxis of chemotherapy-induced nausea and vomiting. Because the number of comparative studies that addressed the delayed nausea and vomiting scenarios is low, further RCTs are still needed to confirm these results.  相似文献   
58.
饶曼人  刘丰 《药学学报》1988,23(2):100-103
尼群的平20μg/kg iv显著降低麻醉犬血压的过程,冠状窦流量明显增加。持续3h,冠状窦氧含量增加,氧摄取率、心肌耗氧量、二氧化碳产生率降低,持续了3h以上,说明该剂适用于高血压伴心肌缺血。  相似文献   
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Sickle cell disease: imaging of cerebrovascular complications   总被引:3,自引:0,他引:3  
Moran  CJ; Siegel  MJ; DeBaun  MR 《Radiology》1998,206(2):311
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