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81.
82.
Question of the Study In this study, safety and feasibility of thoracoscopic fenestration of pleuropericardial cysts under local and general anaesthesia is evaluated. Besides, a rare case of a pleural cyst, causing a superior vena cava syndrome, is described.Materials, Patients and Methods In a retrospective study, the results of thoracoscopic treatment of pleuropericardial cysts in three patients are presented. We performed videothoracoscopic fenestration of pleuropericardial cysts. One of these was performed under local anaesthesia. The two other cases were performed under general anaesthesia. After fenestration, talc poudrage of the inner lining of the cysts was performed in one case.Results Thoracoscopic fenestration appeared to be safe and effective. No recurrence was observed. One patient was lost to follow-up.Answer to the Question Thoracoscopic fenestration of pleuropericardial cysts is safe and effective. This procedure can be performed under local anaesthesia in selected cases. The role of talc poudrage of the cysts is unclear and needs further investigation.  相似文献   
83.
84.
The impact of late muscular injury after radiotherapy on the well being of patients, particularly those treated at a relatively young age, is often underestimated. To extend the present knowledge, a detailed comparative study of the radiation response of skeletal muscles was performed. The hind limb of rats was irradiated at the age of 30-60 days (young), at approximately 200 days (adult) or at the age of >360 days (old), with single doses ranging from 15-60 Gy. Muscular wet weight, volume and tibia length was followed up to 12 months post-treatment. Radiation treatment resulted in muscular wasting, which was more severe at higher doses. The radiation response depended strongly on the age of the animal at the time of treatment. Radiation induced muscle wasting and stunted tibia growth were more prominent in young animals than in adult or in old rats. ED50 values based on normalized wet weight were 12.5 (11.5-13.6) Gy for young animals and 22.5 (21.8-23.3) Gy for adult animals. The gastrocnemius muscle of young animals appears to be more radiosensitive than the gastrocnemius muscle of adult or old animals. Furthermore, in young animals, severe wasting of the muscles may already occur after relative low radiation doses (single dose of 15 Gy).  相似文献   
85.
肾康片质量标准的研究   总被引:4,自引:0,他引:4  
目的:研究肾康片的质量标准并控制该制剂的质量。方法:用薄层色谱法鉴别了肾康片中的黄芪,山茱萸,桑寄生及丹参,用薄层色谱法限量检查屯该制剂中的乌头碱,用双波长薄层扫描法测定了该制剂中黄芪甲苷的含量。结果:乌头碱限量符合中国药典测定,黄芪甲苷的平均回收率为97.5%,其RSD为1.43%。结论:本文的结果显示出这些方法可用于控制该制剂的质量,方法灵敏,简便,专属,准确。  相似文献   
86.
In the current study, negligible depletion solid-phase microextraction (nd-SPME) as a technique to determine tissue/blood (tissue/water and blood/water) partition coefficients was validated. With this method the free fraction of chemicals in water in the presence of different tissues was determined and, subsequently, the partition coefficients were calculated. Liver, blood, muscle, and fat tissues obtained from male Wistar-derived rats (U:Wu) were used without homogenization. Data obtained were compared with literature data for lindane, parathion, and paraoxon. The results show that the data in the present work differ by less than a factor of two from those reported in literature. In addition, the standard deviations obtained show that the technique is accurate. Therefore, we conclude that this accurate and automated method can be used to determine tissue/blood partition coefficients for semivolatile and nonvolatile chemicals.  相似文献   
87.
88.
虚拟现实技术在运动康复中的应用   总被引:1,自引:3,他引:1  
目的:介绍虚拟现实技术在运动功能障碍的康复性训练领域的应用和新发展,讨论虚拟现实技术应用于运动康复的优势和前景。资料来源:应用计算机检索外文期刊PsycINFO和PubMed数据库1996/2006与虚拟现实技术在康复训练中应用相关的文章,检索语种为“English”,检索词为“motor rehabilitation,virtual reality”。检索中文期刊CNKI数据库1996/2006相关的文献,检索语种为中文,检索词为“康复,虚拟现实”。资料选择:根据摘要和关键词对资料进行初选,选择全面介绍虚拟现实技术的文章,以及近几年将虚拟现实技术应用于空间感知障碍和运动功能受损患者康复训练的实验研究报告。资料提炼:在上述3个数据库中分别检索到相关英文文献121篇,以及中文文献21篇,按上述标准纳入18篇,再继续搜索已有文献引用和被引用的参考文献,最后得到相关的中英文文献30篇。资料综合:30篇文献中,4篇文章详细介绍了虚拟现实技术在运动康复领域的应用,26篇实验报告了应用虚拟现实对受损的运动功能进行康复性训练的成效。按照运动康复的种类将研究报告分为4类:平衡和姿态训练、行走训练、上下肢康复训练和日常生活技能训练。通过模仿练习,感知运动受损的患者可以在虚拟环境中完成针对性训练任务,学会运动技能。在虚拟环境中习得的运动技能可以迁移到现实世界的真实任务中。结论:与传统康复训练方法相比,虚拟现实具有更安全、更有趣、针对性强、康复速度快、疗效好等优势。作为一种有效的运动康复技术手段,虚拟现实技术有很好的发展前景。  相似文献   
89.
Weiss  HJ; Turitto  VT; Baumgartner  HR 《Blood》1986,67(2):322-330
Patients whose platelets are deficient in glycoprotein (GP) Ib, IIb- IIIa (thrombasthenia), or granule substances (storage pool deficiency, SPD) were studied to define further the properties of platelets that mediate platelet adhesion and thrombus formation on subendothelium. Both nonanticoagulated and citrated blood were exposed to everted, de- endothelialized rabbit vessel segments under controlled flow conditions and shear rates varying from 650 to 3,300 sec-1. Morphometry was used to measure platelet thrombus dimensions and the percentage of the subendothelial surface covered with contact (C) or spread (S) platelets. Adhesion was defined as C + S. The results in SPD demonstrated (1) reduced thrombus dimensions in delta-SPD (pure dense granule deficiency) in proportion to the magnitude of the dense granule defect; (2) an even greater reduction in thrombus dimensions in patients with combined deficiencies of alpha and dense granules (alpha delta-SPD); and (3) impaired platelet adhesion at several conditions in alpha delta-SPD and, in delta-SPD, a hematocrit-dependent impairment of adhesion in citrated blood at 2,600 sec-1. In thrombasthenia, platelets were present as a monolayer on the subendothelial surface in both nonanticoagulated and citrated blood, indicating an absolute requirement for GPIIb-IIIa in promoting platelet-platelet interaction at all shear rates and perfusion times. Two types of abnormalities in platelet-vessel wall interactions were observed. In nonanticoagulated blood, the percentage of platelets in the C phase was consistently increased at all shear rates, but C + S values were normal. These observations indicate that platelets deficient in GPIIb-IIIa do not spread normally on the subendothelial surface exposed to nonanticoagulated blood. With citrated blood, the C + S value in thrombasthenia was reduced at both 800 and 2,600 sec-1, as in von Willebrand's disease, and a similar degree of reduction (about 50%) was observed in normal blood treated with a monoclonal antibody to GPIIb- IIIa. The findings, together with theoretical considerations, are consistent with an hypothesis that GPIIb-IIIa mediates the spreading of platelets on subendothelium following the initial attachment through GPIb and that GPIIb-IIIa may be considered an adhesion site on the platelet membrane. Abnormalities of GPIIb-IIIa may, depending on the conditions of study, result in either increased values of C platelets or decreased values of C + S. The results of the study further suggest that a complex interaction of platelet granule factors and membrane GP mediate platelet adhesion and thrombus formation.  相似文献   
90.

Objective

To compare the clinical relevance of medication alerts in a basic and in an advanced clinical decision support system (CDSS).

Design

A prospective observational study.

Materials and methods

We collected 4023 medication orders in a hospital for independent evaluation in two pharmacotherapy-related decision support systems. Only the more advanced system considered patient characteristics and laboratory test results in its algorithms. Two pharmacists assessed the clinical relevance of the medication alerts produced. The alert was considered relevant if the pharmacist would undertake action (eg, contact the physician or the nurse). The primary analysis concerned the positive predictive value (PPV) for clinically relevant medication alerts in both systems.

Results

The PPV was significantly higher in the advanced system (5.8% vs 17.0%; p<0.05). Significant differences were found in the alert categories: drug–(drug) interaction (9.9% vs 14.8%; p<0.05), drug–age interaction (2.9% vs 73.3%; p<0.05), and dosing guidance (5.6% vs 16.9%; p<0.05). Including laboratory values and other patient characteristics resulted in a significantly higher PPV for the advanced CDSS compared to the basic medication alerts (12.2% vs 23.3%; p<0.05).

Conclusion

The advanced CDSS produced a higher proportion of clinically relevant medication alerts, but the number of irrelevant alerts remained high. To improve the PPV of the advanced CDSS, the algorithms should be optimized by identifying additional risk modifiers and more data should be made electronically available to improve the performance of the algorithms. Our study illustrates and corroborates the need for cyclic testing of technical improvements in information technology in circumstances representative of daily clinical practice.  相似文献   
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