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71.
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   
72.
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   
73.
Using switching detection and variational equations for the shooting method   总被引:1,自引:0,他引:1  
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   
74.
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   
75.
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   
76.
Previous studies of cerebral structure in substance abusers yielded controversial results, largely due to issues of subject selection and/or limitations of experimental techniques. The purpose of the present study was to assess whether the ventricle-to-brain ratio (VBR), determined volumetrically by magnetic resonance imaging (MRI), differed in polysubstance abusers (n = 10), as compared with age-matched controls (n = 10). Subjects were male volunteers 21–39 years of age. The values of VBR in the polydrug abuse group were not larger than those in control group, nor was there any tendency toward relative ventriculomegaly in the substance abusers. Therefore, the present findings provide no evidence that polysubstance abuse produces abnormalities of gross brain structure in relatively young and physically healthy men.  相似文献   
77.
The performance of the CELL-DYN 1700® (Abbott Diagnostics, Abbott Park, IL, USA) was evaluated in a tertiary care hospital laboratory using the guidelines proposed by the German Society of Clinical Chemistry. Precision, accuracy, linearity, background counts, and carry-over were satisfactory for all measured standard parameters including haemoglobin concentration, haematocrit, red blood cell count, mean corpuscular volume (MCV), red cell distribution width (RDW), white blood cell count and platelet count. With 259 selected normal and abnormal blood samples the results of the CELL-DYN 1700® (CD1700) compared very well (r > 0.96 for all parameters with exception of RDW) with those obtained with the Bayer Diagnostic H-1 and the Hoffmann-La Roche Cobas Argos systems. This study considered in particular the performance of the CD1700 three-part leucocyte differential. For those samples without instrument-generated suspect flags, the neutrophil and lymphocyte percentages were highly correlated with the results of the H-1 blood cell counter (r = 0.97 and 0.98, respectively) and with manual 400-cell differentials (r = 0.91 and 0.88, respectively). In contrast, the CD1700 mid-fraction which comprised the composite total of mono cytes, eosinophils, basophils and precursor white cells (when present) could not be directly compared to the differentials from the H-1 system or from manual microscopy. For those samples with CD1700 instrument suspect flags, the neutrophil and lymphocyte differential results also compared well with both the H-1 (r = 0.93 and 0.93, respectively) and manual estimates (r = 0.89 and 0.87, respectively). In conclusion, the CD1700 is an accurate haematology analyser for cellular blood counts and three-part leucocyte differentiation.  相似文献   
78.
This introduction traces the increasing awareness of the prevalence of child sexual abuse over the last 20 years, examines the nature and consequences of such abuse and summarizes current information on the use of group treatment and its evaluation with sexually abused children and adolescents and their parents. Four examples of group treatment with different populations of abused children are described in this issue.  相似文献   
79.
Conventional treatments have not slowed down the ever expanding low back pain (LBP) problem. Traditional treatment has most probably contributed to the growth of the problem. Therefore, in a search for new solutions, 'functional restoration' has been devised. In connection with chronic LBP the term has been associated with a full-day program lasting from 3 to 5 weeks. it includes multidisciplinary treatment of patients in groups with intensive physical and ergonomic training, psychological pain management, back school, as well as teaching in social/work related issues. The key concepts are 'acceptance of the pain', 'activity', 'self-responsibility', 'multidisciplinary' and 'quantitative functional evaluation (QFE)'. The latter is aimed so that the participants can feel the physical improvement, encouraging them to be able to go back to work, or at least to lead a more active life style. Several controlled studies suggest a lasting effect in terms of regaining their ability to work and improving pain behavior for a good part of disabled chronic LBP patients. However, it is noteworthy that randomized studies seemingly show poorer results than studies not employing randomized controls.  相似文献   
80.
The Italian mental health reform nine years on   总被引:2,自引:0,他引:2  
It is 9 years since the mental health reform was passed by the Italian Parliament. The author presents a data-based evaluation of the effects of the Italian mental health reform. There are still many problems to be resolved: More than 30,000 inpatients are still in psychiatric hospitals and little is known of the fate of those discharged in recent years. District mental health services are still lacking, especially in the south of the country; Psychiatric units in the general hospital function much the same way as the "old" psychiatric hospitals. The pattern of mental health services consumers have changed: They are younger with less severe psychiatric diagnosis and come from a higher social background.  相似文献   
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