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11.
骨巨细胞瘤的MRI诊断价值 总被引:10,自引:0,他引:10
目的探讨骨巨细胞瘤的MRI表现特点及其病理基础。资料与方法搜集经手术病理证实的12例骨巨细胞瘤患者资料,分析其MRI征象并与病理结果对照。结果T1WI上肿瘤实体表现为低、等信号,T2WI上为不均匀高信号,Gd-DTPA增强扫描呈中度到明显强化。此外,MRI还可显示肿瘤内坏死、出血、含铁血黄素沉着等。结论MRI能够提供比较全面的影像学信息,可提高对骨巨细胞瘤诊断的准确性。 相似文献
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Mixed disulfide between lens crystallin and glutathione has been observed in human cataracts and could be formed in vitro by thiol-disulfide exchange reaction. The glutathionyl crystallins have been reported to become partially unfolded. The present paper reports the conformational destabilization by the mixed disulfide formation in calf alpha- and gamma-II crystallin. The conformational stability was studied by the denaturants urea and guanidine hydrochloride (Gdn-HCl), and by proteolytic degradation. The denaturation curves of both urea and Gdn-HCl shift to lower denaturant concentration for crystallins of glutathione mixed disulfide. The decrease in conformational stability is estimated to be 0.22- and 0.92 kcal mol-1 for modified alpha- and gamma-II crystallin, respectively. Proteolytic digestion also shows a faster rate of degradation for the modified crystallins. These results indicate that mixed disulfide destabilizes the crystallin conformation. The destabilization may make crystallins more susceptible to changes as observed in aging lenses. 相似文献
14.
本文对从事京剧打击乐的55人(110耳)进行了听力调查及动态观察。利用图表进行对比分析,发现110耳中高频听力损伤89耳,占81%;语频听力损伤32耳,占29.1%;其中伴有高频耳鸣78耳,占70.9%。动态观察30人(60耳),均为永久性听阈阈移。高频听力损伤最早出现的频率是4kHz,并见典型“V”谷,符合噪声性聋的诊断。 相似文献
15.
D Johnstone M Limacher M Rousseau C S Liang L Ekelund M Herman D Stewart M Guillotte G Bjerken W Gaasch 《The American journal of cardiology》1992,70(9):894-900
The Studies of Left Ventricular Dysfunction (SOLVD) trials were designed to evaluate the effects of enalapril on long-term mortality in patients with severe left ventricular (LV) dysfunction. Patients with LV ejection fractions less than or equal to 0.35 and symptoms of congestive heart failure (CHF) were enrolled in the treatment trial, whereas those with no history of overt CHF and taking no treatment directed for LV dysfunction were enrolled in the prevention trial. The baseline clinical characteristics of SOLVD patients were compared to characterize differences between patients in these 2 separate but concurrent trials. From over 70,000 patients screened with LV dysfunction, 4,228 patients were enrolled in the prevention trial and 2,569 patients in the treatment trial. Ischemic heart disease was the primary cause of LV dysfunction in both prevention (83%) and treatment (71%) trial patients. Prior myocardial infarction was present in 80% of the prevention and 66% of the treatment trial patients (p less than 0.001). In the prevention trial, infarction was recent (less than or equal to 6 months) in 27% patients and remote (greater than 6 months) in 57% patients. Treatment trial patients had proportionately more women (20 vs 13%; p less than 0.001) and non-Caucasians (20 vs 14%; p less than 0.001), as well as the coexisting risk factors of hypertension (42 vs 37%; p less than 0.001) and diabetes (26 vs 15%; p less than 0.001) than did prevention trial patients. Clinical characteristics of patients in both trials were influenced by the gender and race of enrolled patients. Similarly, coronary artery bypass surgery was performed less often in women and non-Caucasians.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
16.
输尿管硬镜处理复杂肾结石残余结石 总被引:2,自引:0,他引:2
目的:提高复杂肾结石的治疗水平。方法:采用输尿管硬镜在术中从肾实质切口,术后从肾造接口取肾内残余结石。结果:5例手术中取石,4例取净;11例手术后取石,其中3例一次取石,5例二次取石,3例三次取石,7例取净。结论:复杂肾结石术中、术后配合输尿管硬镜取石可有效处理残余结石。 相似文献
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目的探讨胃黏膜内pH值对胆源性胰腺炎病情预后评估及在决定手术冶疗中应用的价值。方法对确诊的146例胆源性胰腺炎患者经鼻插入胃黏膜二氧化碳张力计(TRIP-NGS导管)测定胃黏膜内pH值,每隔12小时测定一次,并进行APACHEⅡ评分,将2组数据与外科治疗进行相关分析。结果①pH值变化反映胆源性胰腺炎病情发展变化,与器官衰竭数呈负相关;②外科干预治疗与内科治疗比较差异有统计学意义(P〈0.05);③pHI〉7.25与pH〈7.25患者开腹手术病死率和细菌培养阳性率比较差异有统计学意义(P〈0.05)。结论pH值对胆源性胰腺炎外科治疗有指导意义。外科处理原则是:①胆道无梗阻,以内科保守治疗为主;②伴胆道梗阻,先行经内镜十二指肠乳头括约肌切开术、经内镜鼻胆管引流术、B超导引引流、腹腔灌洗等,如胆道引流不畅或pH值持续下降,则开腹手术。 相似文献
19.
Liang Ying-rui梁英锐Department of Pathology Hunan Medical University Changsha 《中华医学杂志(英文版)》1989,102(1):53-59
The cytoplasm of human bile ductule epithelia was found to be Type V collagen positive, demonstrating that the epithelia were able to generate this type of collagen. The ductules proliferated greatly with Type V collagen positive cytoplasm in piece-meal necrosis of chronic active hepatitis (CAH). The capillary-like bile ductules inside human hepatic lobules were identified. Our findings might explain the mechanism of fibroplasia in CAH. 相似文献
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