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971.
972.
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   
973.
Mucopolysaccharidosis type IIID (MPS IIID) is a lysosomal storage disorder resulting from lack of activity of the lysosomal hydrolase N-acetylglucosamine 6-sulfatase (6S) (EC 3.1.6.14). The syndrome is associated with systemic and central nervous system (CNS) heparan sulfate glycosaminoglycan (HS-GAG) accumulation, secondary storage of lipids, and severe, progressive dementia. In this investigation, caprine MPS IIID, established as a large animal model for the human disease, was used to evaluate the efficacy of enzyme replacement therapy (ERT). Recombinant caprine 6S (rc6S) (1 mg/kg/dose) was administered intravenously to one MPS IIID goat kid at 2, 3, and 4 wks of age. Five days after the last dose, the uronic acid (UA) content and the composition of uncatabolized HS-GAG fractions in the brain of the ERT-treated MPS IIID kid were similar to those from a control, untreated MPS IIID animal. However, hepatic uronic acid levels in the treated MPS IIID kid were approximately 90% lower than those in the untreated MPS IIID control; whereas the composition of the residual hepatic HS-GAG was identical to that in the untreated animal. Marked reduction of lysosomal storage vacuoles in hepatic cells of the treated MPS IIID kid was observed, but ERT had no effect on CNS lesions. No residual 6S activity was detected in brain or liver. This preliminary investigation indicates that other treatment regimens will be necessary to ameliorate MPS III-related CNS lesions.  相似文献   
974.
AIMS: Early invasive lobular breast carcinoma (ILC) is associated with few symptoms and signs. The individual sensitivity of clinical examination, mammography, ultrasonography, cytology and core biopsy have each been reported to be of limited value. The aim of this study was to evaluate the accuracy of triple assessment in the pre-operative detection of patients identified to have ILC from their surgical pathology. METHODS: Pure ILC was defined as tumours containing at least 90% lobular features. The triple assessment of 273 patients diagnosed primarily at our institution were reviewed. RESULTS: 87.5% of women were symptomatic and 12.5% were screen detected. The mean patient age was 59 (range 30-81) years and the median tumour size was 26 (range 5-110) mm. The main mammographic abnormalities were a spiculated lesion (33.3%), an ill-defined mass (33.3%) or architectural distortion (23.5%). The sensitivities for detecting ILC of each modality were: clinical examination (76.6%), mammography (79.8%), ultrasound examination (93.9%), fine-needle aspiration cytology (FNAC) (60.5%) and core biopsy (90.8%). Combining the three modalities of clinical examination, imaging and cyto/pathology increased the pre-operative detection rate of ILC. CONCLUSION: Triple assessment is useful in the diagnosis of ILC. As the features of ILC may be subtle, a high index of suspicion is required to facilitate early diagnosis.  相似文献   
975.
Doppler ultrasound grading of internal carotid artery (ICA) stenosis using the two parameters of spectral analysis and internal carotid to common carotid artery peak systolic velocity (ICA/CCA PSV) ratio is well established. The improvements in B‐Mode ultrasound image quality now make direct ultrasound NASCET‐style stenosis measurement possible. We demonstrate that longitudinal B‐mode imaging can produce accurate North American Symptomatic Carotid Endarterectomy Trial (NASCET) style measurements which have good correlation with angiographic images. Ultrasound B‐mode stenosis measurement provides a third parameter which can be used in conjunction with the two Doppler parameters for the assessment of ICA stenosis. Taking the highest grade of stenosis of the three parameters produces a sensitivity of 100% for the detection of greater than 50% and greater than 80% stenosis with specificity of 66 and 90%, respectively. The performance of satisfactory B‐mode imaging against digital subtraction angiography (DSA) was very encouraging. When the B‐mode stenosis measurement showed a normal ICA, the positive predictive value (PPV) of the DSA being normal was 94%. When the B‐mode stenosis measurement was 35% or less, the PPV of the DSA stenosis being 35% or less was 93%. These excellent results support the use of good quality B‐Mode NASCET style stenosis measurement as the initial ultrasound measurement, with Doppler ultrasound only being performed when the B‐mode stenosis measurement is greater than 35% or if the B‐mode image is unsatisfactory. This approach would save considerable time enabling better utilization of ultrasound resources.  相似文献   
976.
977.
The objective was to evaluate the safety and effectiveness of endoscopic thoracic sympathectomy (ETS) for treatment of a variety of sympathetic disorders, including hyperhidrosis, splanchnic pain, reflex sympathetic dystrophy, and Raynaud upper extremity ischemia. Sixty-three ETS procedures were performed in 34 patients at the University of Maryland Medical System between March 1992 and August 1999 (14 male patients, 20 female patients; mean age 22 years). The indications for surgery were hyperhidrosis in 26 patients, upper extremity ischemia in 3 patients, splanchnic pain and reflex sympathetic dystrophy in 2 patients each, and facial blushing in 1 patient. Preoperative symptoms resolved completely or improved significantly in 97.1% (33/34) of patients. One patient with left reflex sympathetic dystrophy had symptoms that recurred shortly after surgery. There were no major complications; one patient with hyperhidrosis reported significant compensatory hyperhidrosis. These findings suggest that ETS is a safe and effective procedure for treatment of a variety of sympathetic disorders. Its application for hyperhidrosis is very effective, and its treatment of splanchnic pain, reflex sympathetic dystrophy, and Raynaud syndrome are rewarding. With increasing experience, ETS should become established in the repertoire of the thoracic surgeon.  相似文献   
978.
Meta-analysis of benzodiazepine use in the treatment of insomnia   总被引:17,自引:2,他引:15       下载免费PDF全文
OBJECTIVE: To systematically review the benefits and risks associated with the use of benzodiazepines to treat insomnia in adults. DATA SOURCES: MEDLINE and the Cochrane Controlled Trials Registry were searched for English-language articles published from 1966 to December 1998 that described randomized controlled trials of benzodiazepines for the treatment of insomnia. Key words included "benzodiazepines" (exploded), "randomized controlled trial" and "insomnia." Bibliographies of relevant articles were reviewed for additional studies and manufacturers of benzodiazepines were asked to submit additional randomized controlled trial reports not in the literature. STUDY SELECTION: Articles were considered for the meta-analysis if they were randomized controlled trials involving patients with insomnia and compared a benzodiazepine with placebo or another active agent. Of the 89 trials originally identified, 45 met our criteria, representing a total of 2672 patients. DATA EXTRACTION: Data were extracted regarding the participants, the setting, details of the intervention, the outcomes (including adverse effects) and the methodologic quality of the studies. DATA SYNTHESIS: The meta-analyses of sleep records indicated that, when compared with placebo, benzodiazepines decreased sleep latency by 4.2 minutes (non-significant; 95% confidence interval (CI -0.7 to 9.2) and significantly increased total sleep duration by 61.8 minutes (95% CI 37.4 to 86.2). Patient-reported outcomes were more optimistic for sleep latency; those randomized to benzodiazepine treatment estimated a sleep latency decrease of 14.3 minutes (95% CI 10.6 to 18.0). Although more patients receiving benzodiazepine treatment reported adverse effects, especially daytime drowsiness and dizziness or light-headedness (common odds ratio 1.8, 95% CI 1.4 to 2.4), dropout rates for the benzodiazepine and placebo groups were similar. Cognitive function decline including memory impairment was reported in several of the studies. Zopiclone was not found to be superior to benzodiazepines on any of the outcome measures examined. INTERPRETATION: The use of benzodiazepines in the treatment of insomnia is associated with an increase in sleep duration, but this is countered by a number of adverse effects. Additional studies evaluating the efficacy of nonpharmacological interventions would be valuable.  相似文献   
979.
980.
Fetal valproate syndrome and autism: additional evidence of an association   总被引:12,自引:0,他引:12  
Autism has been described in association with a variety of medical and genetic conditions. We previously reported on a patient whose clinical phenotype was compatible with both fetal valproate syndrome (FVS) and autism. Here we present five additional patients with FVS and autism. In all five of our patients, there was evidence of cognitive deficits, manifestations of autism, and typical phenotypic characteristics of FVS. The association between this known teratogen and autism has both clinical and research implications.  相似文献   
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