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61.
62.
将一种快速、灵敏、可靠、简便的抗癌活性微量测定技术——~3H—TdR前体掺入技术用于复方中药抗癌制剂制备工艺筛选,短期内即拟定出较合理的工艺,经临床及14项生物学指标综合评定,该制剂疗效好,无明显的毒副作用。表明把一些快速、灵敏的医学检测技术引入药物制备工艺、质量标准及稳定性研究,可克服由于活性成分不清楚带来的一些困难,拓宽了研究途径,提高了研究水平。 相似文献
63.
Dr M. Weeke-Lüttmann 《European journal of epidemiology》1994,10(4):513-514
The epidemiological situation calls for almost yearly changes in the antigenic composition of influenza vaccine, thus necessitating fresh licensing procedures. Since the time for bringing a new vaccine onto the market should be relatively short, the following work of all parties involved must be done expeditiously: 1) WHO recommendations on new virus strains and their subsequent adaptation by the EEC (February/March); 2) Distribution of the new virus strains to the International Reference Centers for Influenza in the UK and USA (February/ March); the centers later issue reference materials for the determination of the haemagglutinin antigen concentration (April/May); 3) Production and testing of seed virus by manufacturers, as well as validation of the producer's inactivation process for the new virus strains (May/June); 4) Licensing of the vaccines by the National Control Authority (Paul-Ehrlich-Institute) (June/July); in the case of previously licensed products, the procedure is limited essentially to the approval of the detailed protocol of production and tests on the new virus strains, clinical studies not being required before licensing because of a lack of time; 5) Paul-Ehrlich-Institute's test for batch release, according to Directive 89/342/EEC, besides protocol approval, conducts material testing of the endotoxin and antigen content of each vaccine lot; the assay for the antigen quantification is especially laborious and sometimes must be repeated because of test invalidity. 相似文献
64.
突触小泡膜表面突起与微管联系的超微结构研究 总被引:1,自引:0,他引:1
本研究用透射电镜技术观察了大脑皮质(视区)和海马(CA1区和CA3区)的神经终末内的突触小泡和微管间的联系。结果揭示:在适当的超薄切片样品上,常显示出突触小泡膜表面上有短的突起,说明突触小泡是借其膜表面的短突与其它小泡和微管进行联系的。除小泡外,在微管的表面也见一些短突并与小泡发生接触。本文首次报道了用透射电镜方法观察脑内小泡-微管借表面短突连接的联系,提示突触小泡膜表面和微管表面的短突在轴浆运输机制中负有重要的作用。 相似文献
65.
66.
Abstract Daan's two process model is known to be one of the most powerful models, covering various situations from free-running to sleep deprivation. In this study, bifurcation properties of the model dynamics as function of a gap, D , between the threshold processes are clarified using a circle map. As a function of D , we will show that the model has the different types of the mutual entrainment regions that are intervened by the tangent bifurcation. The variable behavior of human circadian rhythm is suggested to be systematically understood based on the bifurcation properties of the two process model. 相似文献
67.
Objective: To explore patterns in the practice of nursing and patient outcomes.
Design: Qualitative field research.
Population, Sample, Setting: Populations were critical care nurses and critically ill adult patients in the 10-bed medical critical care unit of a 900-bed teaching hospital. A convenience-purposive sample of 27 nurses and 31 patients was studied in 1985.
Methods: Six months of participant observation, unstructured interviews, and the constant comparison method of grounded theory.
Findings: Markedly different patterns were found in expert and nonexpert practice. The substantive theory of conversion helped explain how the majority of nonexpert nurses advanced their practice. The metaphor of catalyzed conversion captures how a unit-based expert nurse serves as a catalyst to advance the practice of nonexperts. Presence, defined as the way of being within a given clinical context, differentiated nurses.
Conclusions: (a) Expert and nonexpert practices are substantively different, (b) Expert and nonexpert practice results in different patient outcomes, (c) Conversion helps explain changes in nonexpert practice.
Clinical Implications: A unit-based expert nurse can increase patient-focused care. 相似文献
Design: Qualitative field research.
Population, Sample, Setting: Populations were critical care nurses and critically ill adult patients in the 10-bed medical critical care unit of a 900-bed teaching hospital. A convenience-purposive sample of 27 nurses and 31 patients was studied in 1985.
Methods: Six months of participant observation, unstructured interviews, and the constant comparison method of grounded theory.
Findings: Markedly different patterns were found in expert and nonexpert practice. The substantive theory of conversion helped explain how the majority of nonexpert nurses advanced their practice. The metaphor of catalyzed conversion captures how a unit-based expert nurse serves as a catalyst to advance the practice of nonexperts. Presence, defined as the way of being within a given clinical context, differentiated nurses.
Conclusions: (a) Expert and nonexpert practices are substantively different, (b) Expert and nonexpert practice results in different patient outcomes, (c) Conversion helps explain changes in nonexpert practice.
Clinical Implications: A unit-based expert nurse can increase patient-focused care. 相似文献
68.
本文用OMEGA 500型Υ相机和MCS 560计算系统,即SPECT,R波门控采集心血池图象,在此基础上进行曲线分析,编制BASIC程序计算11项心功能指标。临床应用结果表明:PFR、LVFF、FFR是舒张期功能的优选指标,其它指标对心功能评价也都有显著意义。 相似文献
69.
MIA SON JEONG‐OK KONG SANG‐BAEK KOH JAEYOUNG KIM MIKKO HÄRMÄ 《Journal of sleep research》2008,17(4):385-394
We investigated the effects of 12‐hour shift work for five to seven consecutive days and overtime on the prevalence of severe sleepiness in the automobile industry in Korea. [Correction added after online publication 28 Nov: Opening sentence of the summary has been rephrased for better clarity.] A total of 288 randomly selected male workers from two automobile factories were selected and investigated using questionnaires and sleep‐wake diaries in South Korea. The prevalence of severe sleepiness at work [i.e. Karolinska Sleepiness Scale (KSS) score of 7 or higher] was modeled using marginal logistic regression and included theoretical risk factors related to working hours and potential confounding factors related to socio‐economic status, work demands, and health behaviors. Factors related to working hours increased the risk for severe sleepiness at the end of the shift in the following order: the night shift [odds ratio (OR): 4.7; 95% confidence interval (CI): 3.6–6.0)], daily overtime (OR: 2.2; 95% CI: 1.7–2.9), weekly overtime (OR: 1.6; 95% CI: 1.0–2.6), and night overtime (OR: 1.6; 95% CI: 0.8–3.0). Long working hours and shift work had a significant interactive effect for severe sleepiness at work. Night shift workers who worked for 12 h or more a day were exposed to a risk of severe sleepiness that was 7.5 times greater than day shift workers who worked less than 11 h. Night shifts and long working hours were the main risk factors for severe sleepiness among automobile factory workers in Korea. Night shifts and long working hours have a high degree of interactive effects resulting in severe sleepiness at work, which highlight the need for immediate measures to address these characteristics among South Korean labor force patterns. 相似文献
70.
枢椎齿突骨折的有限元分析 总被引:10,自引:3,他引:10
目的:建立枢椎的三维有限元(FE)模型,探讨在前、后方不同载荷下齿突的不同损伤机制和骨折类型。方法:对一例新鲜枢椎标本进行CT扫描,层厚1mm,扫描图像转换后输入微机,通过软件PRO/E重建枢椎的三维立体模型,再转入有限元软件MARK并赋予此模型物理材料属性,然后模拟齿突骨折的受力条件,在齿突中性矢状面对齿突施加不同角度的载荷,分析各种条件下枢椎模型的应力、应变分布,探讨相应条件下可能导致的枢椎齿突骨折类型。结果:(1)对于齿突前部斜向后下方载荷,应力集中区从齿突前上部斜贯穿至后下部;对于齿突前部斜向后上方载荷,应力集中区从齿突前下部斜贯穿至后上部;齿突腰部始终保持高应力;(2)在齿突后部载荷下,其应力集中情况与前部载荷相似,不过应力集中区位置有所偏下。结论:(1)在齿突中性矢状面,齿突前部载荷容易导致齿突腰部发生断裂,形成枢椎齿突Ⅱ型骨折,也可能导致基底部发生断裂,形成枢椎齿突Ⅲ型骨折;(2)齿突后部载荷更容易导致基底部发生断裂,形成枢椎齿突Ⅲ型骨折。 相似文献