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1. The mean incidence of deaths from ascites in the UK in 1993 was 1.4% (0.7% in 1991 and 0.9% in 1992) and 0.8% from sudden death syndrome (SDS). In total, the economic loss to the UK Broiler Industry in 1993 as a result of these 2 conditions was 24 Pounds M. 2. Clear geographical differences emerged in the occurrence of ascites, with, not only the lowest incidences being observed in Northern Ireland, but also the peak of the mortality from ascites occurring much later in the rearing cycle than in other regions on the mainland. 3. In all regions the incidence of SDS was lower than that of ascites but the reason for this disparity remains to be established. 4. Some of the variables associated with the road transportation of day-old chicks from the hatchery to the farm appeared to influence the incidence of ascites. These included distance or time travelled, stocking density, internal lorry temperature and the length of time the lorry was heated before transport as well as the time the shed was heated before chick arrival. Temperature was also an important factor during growth (brooding and finishing). 5. Negative pressure-powered ventilation was preferred in most organisations but more ascites was seen with positive pressure ventilation. However, the lowest incidence of ascites occurred with natural ventilation. There was more ascites relative to shed orientation when the wind direction was from the west compared to the east. 6. This survey identifies the extent of the problem of broiler ascites in the UK and also highlights the importance of good management control of day-old chicks, not only following placement, but even before their arrival on the farm.  相似文献   
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The Central Medical Pharmaceutical Committee of the Health Insurance Council informs the medical profession annually about the effects of drugs through the Pharmacotherapeutical Compass. The 1998 edition now contains a chapter on pharmacokinetics as well. Compared with previous editions the main alterations of the contents concern an introduction and advice on the antidepressants, two protocols with respect to the medical treatment of patients suffering from epilepsy, advice with respect to oral drugs for the treatment of inflammatory bowel disease, an introduction and advice regarding the treatment of allergic rhinitis, the treatment of patients suffering from AIDS with antiretroviral drugs, the treatment of genital herpes, the taking of insulin lispro by patients with diabetes and the taking of bisphosphonates to prevent or to treat osteoporosis. Two corrections to the 1998 edition are given.  相似文献   
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The Pi typing methods acid starch-gel electrophoresis (ASGE) and isoelectric focusing (IEF) have been compared by three reference laboratories: 564 samples of phenotypes Pi M, MS and MZ were tested in each of the three laboratories with a 96% agreement on initial typing. The discrepancies are recorded and reasons for disagreement discussed. IEF is a reliable method for Pi typing and gives results comparable to those obtained by ASGE.  相似文献   
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Population-based psychiatric admission rates vary across geographic areas, but reasons for this variation are unknown. Insofar as Community Mental Health Centers (CMHCs) provide outpatient services that may deter the need for hospitalization, the presence and structural characteristics of CMHCs may have an impact on a population's psychiatric admission rates. This study uses small area analysis to examine how general hospital psychiatric admission rates are associated with CMHC characteristics. Based on a survey of all CMHCs in Iowa and corresponding small area variation data, it was found that population admission rates were higher in areas closer to the CMHC and lower in outlying catchment areas, adjusting for age, sex, and urban/rural differences in populations. There was little evidence that differences in staffing and service variables influenced admission rates, although greater CMHC staff coverage by social workers and psychiatric residents was associated with lower admission rates. The results suggest that CMHCs do not lower an area's hospitalization rate, and in fact, the presence of CMHCs may promote a "supplier-induced demand" phenomenon of higher admissions.  相似文献   
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Selective regression testing strategies attempt to choose an appropriate subset of test cases from among a previously run test suite for a software system, based on information about the changes made to the system to create new versions. Although there has been a significant amount of research in recent years on the design of such strategies, there has been very little investigation of their cost-effectiveness. The paper presents some computationally efficient predictors of the cost-effectiveness of the two main classes of selective regression testing approaches. These predictors are computed from data about the coverage relationship between the system under test and its test suite. The paper then describes case studies in which these predictors were used to predict the cost-effectiveness of applying two different regression testing strategies to two software systems. In one case study, the TESTTUBE method selected an average of 88.1 percent of the available test cases in each version, while the predictor predicted that 87.3 percent of the test cases would be selected on average  相似文献   
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We investigate how to represent the resulting multivariate information and multidimensional uncertainty by developing and applying candidate visual techniques. Although good techniques exist for visualizing many data types, less progress has been made on how to display uncertainty and multivariate information - this is especially true as the dimensionality rises. At this time, our primary focus is to develop the statistical characterizations for the environmental uncertainty (described only briefly in this article) and to develop a visual method for each characterization. The mariner community needs enhanced characterizations of environmental uncertainty now, but the accuracy of the characterizations is still not sufficient, and therefore formal user evaluations cannot take place at this point in development. We received feedback on the applicability of our techniques from domain experts. We used this in conjunction with previous results to compile a set of development guidelines.  相似文献   
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