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91.
顺铂对结直肠癌肿瘤浸润淋巴细胞杀伤活性的影响 总被引:1,自引:0,他引:1
为在临床选择有效的免疫化疗方案提供一定的理论依据,作者以结直肠癌肿瘤浸润淋巴细胞(TIL)和顺铂(CDDP)为研究对象,对16名手术治疗的结直肠癌患者,分别观察CDDP体内注射及体外预处理TIL和Raji细胞对TIL表面标志和杀伤活性的影响。流式细胞仪检测结果显示,静脉注射CDDP能增加结直肠癌TIL中CD3+/CD4+和CD3+/CD8+细胞含量,同时增强TIL体外杀伤Raji细胞的活性;而体外以CDDP处理Raji细胞能增强其对结直肠癌TIL杀伤的敏感性。作者认为,对于联合应用TIL和CDDP治疗结直肠癌的临床效果有必要进一步研究。 相似文献
92.
基础医学教师课堂教学质量评价 总被引:5,自引:0,他引:5
为了了解本科教师的教学质量和教学效果 ,教学专家和学生评价了 14 7位基础医学教师。结果显示 ,讲师以上职称教师的教学质量明显好于初级职称教师 (P<0 .0 5 ) ,高级职称教师教学的科学性、艺术性和思想性明显好于讲师和助教 (P<0 .0 5 )。文章还对教学中存在的问题和对策进行了讨论。 相似文献
93.
医院综合效益评价中的权数(三)——估计权数 总被引:2,自引:0,他引:2
在医院综合效益评价中,估计权数由评价专家根据经验对评价指标的重要程度的一种评估,这类数据通常用的AHP法进行处理。本文用AHP的递推算法计算估计权数,这种算法不仅计算简单,而且易达到一致性的要求,其估计的剩余误差小于AHP法。 相似文献
94.
Worksite health promotion programs have become increasinglyprevalent in the United States, and one or more health promotionprograms are found in two-thirds of all private worksites with50 or more employees. Reasons for recent growth in program frequencyinclude increased concern for worker health, rapidly escalatingemployer payments for health care benefits to workers, and growingevidence of a strong linkage between employee health and productivity.Published results of evaluations to date suggest that worksitehealth promotion programs can have positive impacts on healthbehaviors and health status. In addition, economic analysesare suggesting that some programs can affect the slope of healthcare costs and have the potential of high cost-effectivenesscompared to some clinical interventions. A number of researchchallenges remain, particularly understanding the influencesof the worksite environment and how employee health promotionprograms affect individual and organizational productivity. 相似文献
95.
Carolien J. Bouma Wiro J. Niessen Karel J. Zuiderveld Elma J. Gussenhoven Max A. Viergever 《Medical image analysis》1997,1(4):363-377
One prerequisite for standard clinical use of intravascular ultrasound imaging is rapid evaluation of the data. The main quantities to be extracted from the data are the size and the shape of the lumen. Until now, no accurate, robust and reproducible method to obtain the lumen boundaries from intravascular ultrasound images has been described. In this study, 21 different (semi-)automated binary-segmentation methods for determining the lumen are compared with manual segmentation to find an alternative for the laborious and subjective procedure of manual editing. After a preprocessing step in which the catheter area is filled with lumen-like grey values, all approaches consist of two steps: (i) smoothing the images with different filtering methods and (ii) extracting the lumen by an object definition method. The combination of different filtering methods and object definition methods results in a total of 21 methods and 80 experiments. The results are compared with a reference image, obtained from manual editing, by use of four different quality parameters—two based on squared distances and two based on Mahalanobis distances. The evaluation has been carried out on 15 images, of which seven are obtained before balloon dilation and eight after balloon dilation. While for the post-dilation images no definite conclusions can be drawn, an automated contour model applied to images smoothed with a large kernel appears to be a good alternative to manual contouring. For pre-dilation images a fully automated active contour model, initialized by thresholding, preceded by filtering with a small-scale median filter is the best alternative for manual delineation. The results of this method are even better than manual segmentation, i.e. they are consistently closer to the reference image than the average distance of all individual manual segmentations. 相似文献
96.
Occupational stress management programmes: a practical overview of published effect studies 总被引:2,自引:0,他引:2
There are many occupational stress management programmes availablewhich are designed to prevent and cure the negative aspectsof job-stress. The focus of the programmes can be directed towardsthe individual worker, the working group, the organization ofthe work or the organization as a whole. Moreover, programmesshow a considerable variation with respect to the type of interventionsthey promote and their underlying assumptions, as well as theirduration and costs. In this paper, effect studies of occupationalstress programmes published between 1987 and 1994 are reviewed.The aim is to give a practical overview of the variety in occupationalstress programmes, their scope, applicability and the evidenceof their effectiveness. The paper updates the review by DeFrankand Cooper published in 1989. 相似文献
97.
Obstructive sleep apnoea is a relatively common sleep disorder that is popularly associated with snoring and excessive daytime sleepiness. It is a disorder with serious implications that has only in the last two decades received the attention of clinical specialists. The aim of this article is to review the role of the dental profession in the recognition and management of this disorder. 相似文献
98.
We study in this paper the resolution by single shooting of an optimal control problem with a bang‐bang control involving a large number of commutations. We focus on the handling of these commutations regarding the precise computation of the shooting function and its Jacobian. We first observe the impact of a switching detection algorithm on the shooting method results. Then, we study the computation of the Jacobian of the shooting function, by comparing classical finite differences to a formulation using the variational equations. We consider as an application a low thrust orbital transfer with payload maximization. This kind of problem presents a discontinuous optimal control, and involves up to 1800 commutations for the lowest thrust. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
99.
Evaluating projects funded by the Western Australian Health Promotion Foundation: first results 总被引:1,自引:0,他引:1
HOLMAN C. D'ARCY J.; DONOVAN ROBERT J.; CORTI BILLIE; JALLEH GEOFFREY; FRIZZELL SHIRLEY K.; CARROLL ADDY M. 《Health promotion international》1996,11(2):75-88
The paper describes output measures of performance of the WesternAustralian Health Promotion Foundation (Healthway), using asystem known as graduated project evaluation (GPE). Resultsare reported at the basic and process levels of evaluation on588 health and sponsorship projects, and at the impact levelbased on surveys of 5710 spectators and participants at 53 sport,arts and racing events sponsored by Healthway funds. At thebasic and process levels the average Healthway project reached7449 people directly and generated media coverage of healthmessages on 27.3 occasions. It secured, on average, 0.99 healthystructural reforms in recreational or cultural venues, involvedthe participation of local community members in project administrationin 38% of instances, and provided 1596 person-hours of healtheducation. Non-smoking, safe drinking, nutrition, exercise,sun protection, safe sex and injury prevention health messageswere promoted using 24 different types of sponsor benefits.Of the 5710 respondents surveyed post-event, 67% were awareof the promoted health message and 82% of these understood whatthe message meant. Four per cent of all respondents intendedto take action ranging from seeking information to adoptingthe health behaviour. A comparison of the cost-effectivenessof small and large sponsorship projects is given to illustratethe use of GPE to inform funding decisions. Smaller projectsoutperformed larger projects on all available indicators. Wediscuss the peculiar features of the health promotion foundationconcept, methods to improve its performance and implicationsfor future research. 相似文献
100.
The assessment of economic and quality-of-life outcomes of health care interventions is moving into a new era, with such assessments increasingly being made within the context of controlled clinical trials. Traditionally the measurement of many variables in economic evaluations, particularly costs, has been deterministic. In the context of clinical trials the measurement of variables is stochastic, with the standard principles of statistical inference being applied to analyse differences between treatments in terms of effectiveness. Economists participating in clinical research are therefore being called upon to specify the sample size for the economic component of the evaluation and to undertake statistical tests for differences in cost or cost-effectiveness. This paper discusses the current methodological issues surrounding stochastic measurement in clinical trials, discusses the additional issues raised by the assessment of economic and quality-of-life outcomes and specifies the challenges facing economists if they are to answer the questions now being posed about economic analysis by statisticians and clinical researchers. It is concluded that application of the standard principles of statistical inference to economic data is not straightforward and will require value judgements to be made about statistical significance and economic importance, which may differ from those already made in purely clinical studies. 相似文献