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Fibrosarcoma is a rare tumour in children. The potential of malignancy has been questioned. We present three cases of fibrosarcoma in children. The follow-up periods range from 10 to 37 years. The first patient had pulmonary metastases at the time of diagnosis in 1958. The primary tumour in fossa ischio-rectalis was resected in 1960. Lung metastases were resected in 1960 and 1989. Radiotherapy was given in 1992. He is still alive with metastases 37 years after the first manifestation of disease. The second patient had a primary tumour and several local recurrences in the mandible. He is alive without evidence of disease 4 years after resection of pulmonary metastases and 21 years after resection of the primary tumour. The third patient has no signs of recurrence or metastasic spread 10 years after a wide excision of subcutanous tumours of the left upper arm. The cases demonstrate a special tumour-entity of low-grade malignancy, which show a good prognosis and a wide spectrum of biological behaviour.  相似文献   
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Objective

To determine the extent to which thin-section and volumetric three-dimensional CT can depict airway reactivity to bronchostimulator, and to assess the effect of different airway sizes on the degree of reactivity.

Materials and Methods

In eight dogs, thin-section CT scans were obtained before and after the administration of methacholine and ventolin. Cross-sectional areas of bronchi at multiple levels, as shown by axial CT, proximal airway volume as revealed by three-dimensional imaging, and peak airway pressure were measured. The significance of airway change induced by methacholine and ventolin, expressed by percentage changes in cross-sectional area, proximal airway volume, and peak airway pressure was statistically evaluated, as was correlation between the degree of airway reactivity and the area of airways.

Results

Cross-sectional areas of the bronchi decreased significantly after the administration of methacholine, and scans obtained after a delay of 5 minutes showed that normalization was insufficient. Ventolin induced a significant increase in cross-sectional areas and an increase in proximal airway volume, while the effect of methacholine on the latter was the opposite. Peak airway pressure increased after the administration of methacholine, and after a 5-minute delay its level was near that of the control state. Ventolin, however, induced no significant decrease. The degree of airway reactivity did not correlate with airway size.

Conclusion

Thin-section and volumetric spiral CT with three-dimensional reconstruction can demonstrate airway reactivity to bronchostimulator. The degree of reactivity did not correlate with airway size.  相似文献   
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PURPOSE: The purpose of this paper is to review the effect of intralesional corticosteroid therapy in the treatment of 155 head and neck hemangiomas. METHODS: In the past 10 years, we have treated 155 proliferating head and neck hemangiomas with intralesional corticosteroid injections. Three to 6 injections of triamcinolone acetonide (10 mg/mL) in monthly intervals were given. Using slides and chart review, the results were assessed 1 month after completion of the treatment. RESULTS: Eighty-five percent of the lesions showed greater than 50% reduction in volume. Varied treatment response was noted in different classes of hemangioma. Eighty percent of the superficial, 75% of the deep, and 60% of the combined hemangiomas show more than 50% reduction in volume. Further growth was not found after treatment. The postinjection complication rate was 6.4% in this series. There were 2 patients with cushingoid appearance, 5 with cutaneous atrophy, and 3 suffered from anaphylactic shock. We found that lesions showing less than 50% reduction in volume were located mostly in the perioral area. CONCLUSIONS: Intralesional corticosteroid injections are safe and effective in arresting hemangioma proliferation. Superficial hemangiomas yield the best results.  相似文献   
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Studies using a variety of investigative methods, including functional brain imaging and electroencephalography (EEG), have suggested that changes in central nervous system (CNS) dopamine function result in altered visual system processing. The discovery of abnormal retinal blue cone, but not red cone, electroretinogram in association with cocaine withdrawal and Parkinson's disease suggests that visual system response to blue light might be a marker for CNS dopamine tone. As there are numerous sex-related differences in central nervous system dopamine function, we predicted that blue and red light stimulation would produce sex-specific patterns of response in primary visual cortex when studied using the blood oxygen level dependent (BOLD) functional magnetic resonance imaging (fMRI) technique. We analyzed the BOLD response to red and blue light in male and female human volunteers (N=20). Red and blue light responses in primary visual cortex (V1) to stepped intensities of red and blue light were compared by sex for threshold to detectable BOLD signal increase and for stimulus intensity vs. BOLD signal response. Near threshold, males and females showed similar BOLD signal change to red light, but males showed a threefold greater increase (0.52%) to blue light stimulation when compared to females (0.14%). Log-linear regression modeling revealed that the slope coefficients for the red light stimulus intensity vs. signal change curve were not significantly different for males and females (z=0.995, P=0.320), whereas the slope coefficients for the blue light stimulus intensity vs. signal change curve were significantly larger in males (z=2.251, P=0.024). These findings support a sex and color-dependent differential pattern of primary visual cortical response to photic stimulation and suggest a method for assessing the influence of specific dopamine agonist/antagonist medications on visual function.  相似文献   
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纳洛酮治疗原发性脑干损伤   总被引:10,自引:0,他引:10  
目的 :观察纳洛酮治疗原发性脑干损伤的疗效。方法 :83例原发性脑干损伤病人分为纳洛酮组 38例 ,在常规治疗基础上加用纳洛酮 0 .3mg·kg- 1加入氯化钠注射液 5 0 0mL中静脉滴注 ,qd× 3d ,3d后减为 4 .8mg·d- 1,qd× 7d ,10d为一个疗程 ;常规治疗组 4 5例 ,单用常规治疗。按格拉斯哥昏迷评分标准观察病人症状。结果 :常规治疗组和纳洛酮组的昏迷时间分别为 (30±s 4 )d和 (2 0±4 )d ,死亡分别为 16例和 6例 ,恢复良好分别为 12例和 2 3例 ,中残分别为 7例和 6例 ,重残分别为 10例和 3例、植物生存各 1例 ;2组昏迷时间及疗效比较 ,P <0 .0 1。结论 :纳洛酮在原发性脑干损伤的治疗中能降低死亡率 ,缩短昏迷时间 ,减少残存率。  相似文献   
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