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个体化下肢小腿假肢接受腔设计的生物力学评价技术研究   总被引:3,自引:0,他引:3  
作为传递体重、固定假肢的部件 ,接受腔对于小腿假肢使用的舒适性和方便程度有决定性的作用。本研究建立了基于有限元应力分析的小腿假肢生物力学评价技术平台 ,实现了小腿残端 /接受腔 3D几何建模与信息交互、三维有限元自动建模及应力分析。 3D模型与信息交互的实现基于得到广泛支持的OpenGL技术 ,有限元模型的构建采用了专门针对小腿残端 /接受腔结构特点的自动建模方法 ,通过构建档案数据库系统作为整个系统的操作平台。该技术平台可与现有的CAD/CAM系统相结合 ,为接受腔的个体化设计提供生物力学定量化依据。其临床应用将改善传统的设计流程 ,提高设计效率。同时 ,它也是未来构建接受腔设计专家 /智能系统的基础。  相似文献   
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Lung carcinoma remains one of the most frequent and aggressive human neoplasms. Fortunately, in the last decades, the increasing knowledge of the molecular mechanisms leading to cancer development has allowed the use of targeted therapies with improvement of prognosis in many patients. Clinical management has also changed after the introduction of endobronchialultrasonographic bronchoscopy that allows a conservative staging of lung tumors, avoiding the need of mediastinoscopy for lymph node staging. Lung pathologists and cytopathologists are facing the challenge of giving the more comprehensive prognostic and predictive information with ever smaller tissue or cytological samples. The aim of this review is to summarize the molecular testing for non-small cell lung carcinoma and how pathologists can contribute to the patient's outcome with a conscious management of biological samples.  相似文献   
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Using the UV-mimetic mutagen 4-nitroquinoline-1-oxide (4NQO) to induce genetic damage in human cells (lymphoblastoid lines and primary cultures of peripheral blood samples), chromosome aberrations were induced by treating the cells with 4NQO at 1 X 10(-5) M for 24 h. The overwhelming majority of chromosome aberrations was of the chromatid (S + G2) type instead of the chromosome (G1) type. The most common chromatid aberrations were simple breaks, isochromatid breaks, and chromatid exchanges. When the number of chromatid breaks per cell value was used as a measurement for 4NQO sensitivity, lymphoblastoid cells from a xeroderma pigmentosum patient showed the highest sensitivity, followed by the cells of two melanoma patients and normal persons. These preliminary results suggest that 4NQO may be employed to develop an assay system as a biomarker for determining UV sensitivity in the human population.  相似文献   
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碱离子水饮用后血小板聚集率的的变化(附30例报告)   总被引:1,自引:0,他引:1  
目的:报告30例饮用豪斯牌碱离子水前、后血小板聚集率的变化。方法:饮用碱离子水前、后(2~3月,>3~6月)作比浊法血小板聚集试验,以1分钟、5分钟及5分钟内最大聚集率(Max%)为指标,同时检测部分血粘度指标及凝血因子,并用自动生化仪检测血糖、血脂、主要电解质及部分肝、肾功能。结果:饮碱离子水后,血小板聚集率明显下降,而以疾病组(Max>80%)下降尤为明显,P均<0.001。饮碱离子水后血小板聚集率的下降,部分可能与损伤的血管内皮得到修复有关。主要电解质及部分肝、肾功能无明显异常改变。结论:由于心、脑血管血栓性疾病患者血小板聚集率多明显升高,饮碱离子水后血小板聚集率明显下降,且长期饮用对主要电解质及部分肝、肾功能无明显异常改变,作者认为碱离子水使用方例、安全、有效、价廉,因而对心、脑血管血栓性疾病防治方面可能是一种积极的辅助方法,值得临床进一步探索。  相似文献   
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BackgroundPrescribing errors are prevalent in hospital settings with provision of feedback recommended to support prescribing of doctors. Feedback on prescribing has been described as feasible and valued but limited by doctors, with pharmacists described as credible facilitators of prescribing feedback. Evidence supporting prescribing feedback has been limited to date. A formalised programme of pharmacist-led prescribing error feedback was designed and implemented to support prescribers.ObjectiveTo evaluate the impact of a prescribing feedback intervention on prescribing error rates and frequency of prescribing error severity and type.MethodProspective prescribing audits were undertaken across sixteen hospital wards in a UK teaching hospital over a five day period with 36 prescribers in the intervention group and 41 in the control group. The intervention group received pharmacist-led, individualised constructive feedback on their prescribing, whilst the control group continued with existing practice. Prescribing was re-audited after three months. Prescribing errors were classified by type and severity and data were analysed using relevant statistical tests.ResultsA total of 5191 prescribed medications were audited at baseline and 5122 post-intervention. There was a mean prescribing error rate of 25.0% (SD 16.8, 95% CI 19.3 to 30.7) at baseline and 6.7% (SD 9.0, 95% CI 3.7 to 9.8) post-intervention for the intervention group, and 19.7% (SD 14.5, 95% CI 15.2 to 24.3) at baseline and 25.1% (SD 17.0, 95% CI 19.8 to 30.6) post-intervention for the control group with a significant overall change in prescribing error rates between groups of 23.7% (SD 3.5, 95% CI, ?30.6 to ?16.8), t(75) = ?6.9, p < 0.05. The frequency of each error type and severity rating was reduced in the intervention group, whilst the error frequency of some error types and severity increased in the control group.ConclusionPharmacist-led prescribing feedback has the potential to reduce prescribing errors and improve prescribing outcomes and patient safety.  相似文献   
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Reducing student problem behavior remains a leading concern for school staff, as disruptive and aggressive behavior interferes with student achievement and the school climate. However, the multisystemic nature of schools makes it difficult for researchers and practitioners to identify factors influencing to students’ behavior. The current study examined student problem behavior through an ecological lens by taking into account individual (e.g., gender, ethnicity, prosocial behavior), classroom (e.g., class size, average classroom behavior), and school-level factors (e.g., location, school climate). Using data from 37 elementary schools, 467 classrooms, and 8,750 students, a series of hierarchical linear models were tested. Multilevel analyses revealed that while individual student characteristics had the largest influence on problem behavior, average prosocial behavior and concentration problems of students within the classroom, as well as teacher perceptions of the school climate significantly related to how students behaved. These findings support the use of classroom-based intervention programs to reduce student problem behavior.  相似文献   
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Racial differences in the prevalence of complex thoracic aortic atheroma were evaluated in 318 patients referred for transesophageal echocardiography after unexplained stroke or transient ischemic attack. African-Americans were found to have fewer complex thoracic aortic atheroma and fewer combined cardiac sources of embolus than Caucasian patients. This finding persists after adjusting for racial differences in atherosclerotic risk factors.  相似文献   
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