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21.
Zusammenfassung Medikamente – insbesondere solche mit zentralnervöser Wirkung – können einerseits die Fahrsicherheit einschränken, andererseits kann durch eine Arzneimitteltherapie eine krankheitsbedingt eingeschränkte Fahrsicherheit gebessert bzw. eine Fahreignung wiederhergestellt werden. Für die verschiedenen verkehrsmedizinisch bedeutsamen Arzneimittelgruppen werden im Folgenden die relevanten Leistungseinbußen dargestellt. Die dem Arzt im Zusammenhang mit einer Arzneimitteltherapie obliegenden umfangreichen Beratungs- und Hinweispflichten für seinen Patienten werden ebenfalls vorgestellt. 相似文献
22.
重组合异种骨(RHB)骨形成蛋白(BMD)与去除抗原特性后的异种松质骨的复合物,是近年来医学研究的一个新成果。既具有BMP的高度诱导成骨作用,又具有松质骨的支架作用,十分便于临床使用、填充骨缺损。作者等应用RHB治疗16例骨缺损及骨不连,证实它是一种高效的成骨诱导物质,诱导生骨作用肯定,无明显副作用,临床使用方便,较自体骨移植愈合时间快,避免了取自体髂骨的痛苦。作者等认为,本生物制品颇值得大力推广应用。 相似文献
23.
A patient with cavernous transformation of the portal vein and a suspected hepatic mass lesion underwent an ultrasound-guided aspiration of the liver with a skinny needle. Two days later he became acutely ill. Bilirubin level peaked at 1375 mumol/L (80.4 mg/dL), and alkaline phosphatase level was 2290 IU/mL. There was no evidence of biliary obstruction. A biliary-vascular fistula was diagnosed by endoscopic retrograde cholangiography, and nasobiliary drainage was placed, leading to resolution of the symptoms and jaundice. A pressure gradient between the biliary tree and a venous collateral probably led to flow of bile into a blood vessel. Nasobiliary drainage should be considered as a potential therapy for acute biliary-vascular fistula. 相似文献
24.
目的总结钻颅碎吸治疗高血压性脑出血的疗效。方法利用配对方法与保守治疗病人进行对比。碎吸组反复穿刺血肿,调整血压。对照组采取降颅压,营养脑细胞等内科治疗。结果碎吸组病死率15.6%,对照组病死率27%,两组相比P<0.05,CT观察发现,碎吸治疗可加速血肿的吸收。半年后随访结果表明,碎吸治疗可降低致残率。结论钻颅碎吸术可作为治疗部分高血压性脑出血病人的理想选择。 相似文献
25.
乳酸氧化酶分离纯化的研究 总被引:2,自引:0,他引:2
粪链球菌发酵液经菌体破壁、丙酮分级沉淀、硫酸铵盐析、DEAE-纤维素柱色谱,Sephadex G-150分子筛和 Sephadex A-50柱色谱等分离步骤,制得较纯的乳酸氧化酶,可用于酶盒测定。 相似文献
26.
This paper presents a method of improving the TLD-100 dose reassessment performance. This method consists of applying numerical analysis techniques for evaluating the TLD-100 phototransferred thermoluminescence (PTTL) glow curve. From this analysis, a simple procedure for estimating the ultraviolet background components usually present in phototransferred thermoluminescence (TL) signals has been established. This procedure has been implemented in a computer program which performs the automatic evaluation of the glow curves and extracts the dose information contained in the PTTL curves. The use of this computer-aided evaluational method has enabled the extension of the working range of estimated absorbed dose down to 0.2-0.5 mGy with very adequate operational quality for doses even below the conventionally admitted lower reestimation limit (approximately 2 mGy). Because TL readout is a destructive process, the ability to reestimate doses can be important in any kind of dosimetric activity, such as operational dosimetry programs. The other commonly used dosimeter, film, uses a nondestructive readout and, therefore, presents some advantages over TLD when dose reassessment is necessary. With the reported improvements in the TLD-100 dose reassessment performance, the full range of absorbed doses covered by film dosimetry can now be reliably reassessed using TLD-100 dosimeters. 相似文献
27.
28.
目的研究可控性丝线的致栓效果及其治疗体表难治性海绵状静脉畸形的初步疗效。方法将丝线一端留置于不同管腔大小的静脉内,另一端挂于血管壁埋于皮下,实现其可控性,用经过不同处置的丝线,分别留置于兔耳缘静脉、股静脉,观察其引起血管栓塞的效果。选择致栓效果较好的丝线组,用于临床治疗难治性体表海绵状静脉畸形的患者。结果几种经不同处置的丝线,均能不同程度地起到闭塞血管的作用,对于管腔稍大,血流较快的静脉(兔股静脉),浸泡丝裂霉素并打结的丝线组,致栓效果最好;临床初步应用证实,可控性丝线治疗体表难治性静脉畸形,安全有效。结论可控性丝线静脉内留置术,是一种安全、有效、损伤小、操作简便的治疗体表难治性海绵状静脉畸形的新方法。 相似文献
29.
The effect of fraction time in intensity modulated radiotherapy: theoretical and experimental evaluation of an optimisation problem. 总被引:3,自引:0,他引:3
Xiangkui Mu Per-Olov L?froth Mikael Karlsson Bj?rn Zackrisson 《Radiotherapy and oncology》2003,68(2):181-187
BACKGROUND AND PURPOSE: In intensity modulated radiotherapy (IMRT), the complexity and the number of treatment fields have expanded. This may imply that the delivery time for each fraction becomes prolonged. In a number of IMRT techniques used in the clinic, the delivery time per fraction is usually 10-15 min, sometimes more than 15 min. In studies on human skin, prolonged delivery time is shown to cause significant reduction of radiation effects compared with acute irradiation. In this paper the effect of changes in fraction delivery time was studied by in vitro irradiation of mammalian cells. MATERIAL AND METHODS: Chinese hamster fibroblasts (V79-379-A) were used for simulating clinical situations. Most experiments were performed with 2Gy/fraction with 4-h intervals in 40-60 replicates. Each fraction was divided into different subfractions, simulating the delivery of a complicated treatment. The effect of changing the delivery time for each fraction was studied. Parameters for the cell survival curve and repair kinetics were determined experimentally. The same methods were also used for large fraction sizes (8Gy). The validity of the most widely used models in the literature, all derived from linear-quadratic formalism, were tested against the experimental results. RESULTS: The effect of prolonging the fraction time for 2-Gy fractions was underestimated by the biological models. The experiments showed that 10-min prolonged delivery time gave a ratio between surviving fractions at 2Gy (S-ratio) of 1.054 with a 95% confidence interval (CI) 1.030-1.080, while the models predicted 1.007 and 1.009. Extending the fraction time to 20 min gave an S-ratio of 1.063 with CI of 1.045-1.080, while the models predicted 1.012 and 1.014. For 8-Gy fractions, there was a good agreement between predications and experimental results. The ratio between surviving fractions at 8Gy is 1.370 with CI of 1.300-1.440, while the models predicated 1.37 and 1.35. CONCLUSIONS: The effect of prolonging fraction time at conventional dose/fraction is underestimated by biological models. Prolonging the fraction time will spare tissues with a fast DNA repair. There is a risk for sparing tumours. This should be considered when IMRT technique is implemented in the clinic. 相似文献
30.