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We present 36 consecutive patients with intrinsic glioma of the pons. Tumors with exophytic expansion were excluded. There were 16 females and 20 males, ranging in age from 2 to 13 years, median 6 years. The most common presenting symptoms were cranial nerve dysfunction. unsteadiness of gait, and hemiparesis. Computed tomography (CT) showed a hypodense (17/21) or isodense (4/21) expansion of the pons. Five tumors had areas of contrast enhancement. Following information about prognosis and possible types of management, parents decided for or against radiation therapy: twentyfour children underwent irradiation and 12 did not. Median survival among children receiving a full course of irradiation was 280 days, compared to 140 days in an equivalent group of non-irradiated children. Hemiparesis presenting without cranial nerve symptoms and contrast enhancement on CT scan were poor prognostic factors, whereas sex, age, and duration of symptoms at diagnosis were unrelated to prognosis.  相似文献   
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We compared the efficacy of flecainide versus quinidine in preventing paroxysms of atrial fibrillation in a randomized open crossover study. Twenty-six patients with weekly attacks of atrial fibrillation during the last 3 months, objectified by 24-h holter monitoring or 12-lead electrocardiogram (ECG) were treated for a period of 3 months with flecainide 100 mg b.i.d. or quinidine 500 mg b.i.d. Efficacy was assessed by 24-h holter monitoring and a questionnaire at the end of each month. Dosage was adjusted to flecainide 100 mg t.i.d. or quinidine 500 mg t.i.d. if patients still had symptomatic paroxysms of atrial fibrillation according to a questionnaire or on holter monitoring. In 46% of the patients, flecainide 100 mg b.i.d. caused total abolition of supraventricular tachycardia; after dose adjustment it caused 50% total abolition. For quinidine, the figures are 16% (p less than 0.05) and 32% (NS), respectively. Side effects occurred with flecainide only after dose adjustment (23%), but on quinidine they occurred before (8%) and after dose adjustment (20%). We conclude that flecainide suppresses paroxysms of atrial fibrillation significantly more often as compared with quinidine in the lower dosage regimen. Optimal treatment dosage of flecainide is 100 mg b.i.d. After quinidine dose adjustment, the difference in efficacy is no longer significant. However, side effects necessitating discontinuation of quinidine developed in 20% of the patients as compared to none in patients treated with flecainide 100 mg b.i.d.  相似文献   
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Zusammenfassung Bei einem 55jährigen Mann wurde 7 Monate nach orthotoper Lebertransplantation eine Lungentuberkulose diagnostiziert. Die tuberculostatische Therapie erfolgte mit Isoniazid (3 x 0,2 g/Wo) und Ethambutol (1,6 g/d) über 11 Monate. Nach 3 Monaten waren keine Mycobakte rien mehr nachweisbar, und der Patient ist im 3. Jahr nach Transplantation ohne Zeichen einer aktiven Tuberkulose in gutem Gesundheitszustand bei guter Transplantatfunktion. Die Tuberculostatica-Dosierung sollte je nach Metabolisierungsleistung des Transplantats reduziert werden. Bei Beachtung dieses Kardinalpunktes könnte eine Tuberkulose nach Lebertransplantation erfolgreich behandelt werden.  相似文献   
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Objective To investigate the effects of tissue specific cytosine deaminase/5-fluorocytosine (CD/5-FC) thermotherapy on hepatic metastasis of colonic carcinoma in nude mice. Methods Forty-five nude mice were randomly divided into control group, 5-FC group and 5-FC thermotherapy group according to the random number table (15 mice in each group). Mice models of hepatic metastasis of colonic carcinoma were established by portal vein injection of LoVo/CEACD cells. The hepatic metastasis rate and number of metastatic nodules of the 3 groups were compared by ehi-square test and one-way ANOVA. The pathological changes in tumor tissues and apoptotic index of tumor cells were observed. The expression of the CD gene in tumor tissues was detected by fluorescent quantitative RT-PCR and Western blot. Results The number of metastatic nodules and liver metas-tasis rate were 4.6±1.3 and 100.0% in control group, 2.2±1.0 and 60.0% in 5-FC group, 0.5±0.8 and 13.3% in 5-FC thermotherapy group, with statistical difference among the 3 groups (F=25.898, χ2=5.208, 19.548, 5.168, P<0.05). The mean apoptotic indexes of tumor cells of the 3 groups were 4.6%, 9.9% and 17.4%, respectively. Vacuolar degeneration, cell necrosis, cytolysis and apoptotic bodies were mostly observed in the 5-FC thermotherapy group. The expression of CD gene in tumor tissue was detected in all the groups. Conclusion Tissue specific CD/5-FC thermotherapy has inhibitory effects on the hepatic metastasis of LoVo cells transfected with CD gene.  相似文献   
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碳纤维根管桩的研制   总被引:1,自引:0,他引:1  
目的研究高强度碳纤维增强复合树脂根管桩的加工成型工艺.方法用湿法制备碳纤维预浸料,在预成型模具中预成型,然后在成型模具中经特殊的工艺进行成型,最后用车床加工成预定形状的桩钉;并测试其弯曲强度、剪切强度和碳纤维含量.结果随着碳纤维含量的增加,根管桩的弯曲强度和剪切强度均逐渐增加.碳纤维含量达到67.13%时,弯曲强度和剪切强度分别达到406MPa和653.86MPa.结论高强度的碳纤维根管桩可以满足临床需要.  相似文献   
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目的 探讨以聚羟基乙酸(PGA)包裹特定形态的医用假体材料--多孔高密度聚乙烯(HDPE,商品名为MEDPOR)为支架,应用软骨细胞诱导骨髓基质干细胞(BMSCs),共培养构建特定形态的带内支撑组织工程化软骨医用假体的可能性.方法 以直径3 mm、长5 mm的圆柱形HDPE,外裹 1 mm厚PGA为支架,将体外分别培养的新生猪BMSCs和耳郭软骨细胞按7∶3混合,以10×10 7/ml细胞浓度接种于支架上,同时以相同浓度的单纯软骨细胞和单纯BMSCs分别接种,作为阳性对照组(PC组)和阴性对照组(NC组).经体外培养2周及在裸鼠皮下移植4、8周后取材 ,行大体观察、组织学、组织化学及免疫组化检测.结果 各组细胞均与材料黏附良好.实验组和阳性对照组均形成了大体形态良好的HDPE-软骨复合体,内支撑的HDPE与外层软骨结合紧密.组织学可见成熟的软骨陷窝结构,软骨渗入HDPE孔隙内部、异染基质及Ⅱ型胶原呈强阳性表达.结论 以HDPE为内支撑,外裹PGA的支架,接种混合细胞,可于皮下构建特定形态、组织学良好的HDPE-软骨复合体.  相似文献   
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Summary Background Pregnancy is prossible in female patients who underwent cardiac transplantation but is associated with unpredictable risks. Methods A 23-year old female patient underwent cardiac transplantation because of dilatative cardiomyopathy. Results Against our advice, she became pregnant 4 months after transplantation. Following an uneventful pregnancy, spontaneous vaginal delivery occurred 13 months after transplantation. The patient gave birth to a healthy new-born in good physical condition. Thereafter, the patient refused to attend any further routine follow-up control. 9 months after delivery, the patient was admitted to hospital in severe cardiac shock. Biopsy showed a serious, acute rejection which was treated with a course of methylprednisolone. Clinically, the patient recovered within 1 week, but died from acute myocardial infarction 1 day after discharge from hospital. Conclusions Only women without a history of rejection episodes, with good kidney function, good graft function, and high compliance should be counselled to become pregnant.   相似文献   
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目的探讨肾动脉狭窄介入治疗前后血清脑利钠肽BNP水平的变化及意义。方法采用回顾性调查方法,对肾动脉狭窄介入治疗前后血清脑利钠肽水平的变化进行分析。结果肾动脉狭窄介入治疗再通后,血清BNP水平出现下降(P〈0.01)。结论血清BNP水平的变化对肾动脉狭窄介入治疗后疗效的评价具有一定的临床指导意义。  相似文献   
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