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21.
在城市发展和改造过程中,英国近代城市先后着手进行城市公共空间———公园建设,从而掀起了一场造园运动。这场运动既是英国城市发展的必然结果,同时也是解决城市环境问题、提高大众健康水平的需要。而公园等公共空间的建设,为居民提供了一个锻炼与休闲的空间,有利于提高居民的健康水平。健康的人居环境,为各阶层民众提供了聚会的场所,体现了社会成员和谐相处的精神,成为英国资本主义成熟的重要表现之一。  相似文献   
22.
目的:考察主动到心理咨询中心求助的大学生自我表露和孤独状况并与普通大学生的资料进行比较;考察来访者对咨询员的自我表露与其他目标人的表露之差异。结果发现:求询大学生与普通大学生的自我表露相比显著地低;求询大学生对咨询员的表露比其他目标人的表露显著地高;求询大学生的孤独感明显地高于普通大学生;心理咨询在大学生发展过程中起着重要的作用。  相似文献   
23.
企业改制是建立现代企业制度的必要途径。资产评估是企业改制中必不可少的重要环节。资产评估应明确评估目的、评估基准期、评估对象 ,掌握正确的评估方法和规范的评估程序。在企业改制中要特别注意设计稳妥的剥离方法 ,对非经营性资产和非经营性人员进行合理的剥离  相似文献   
24.
Summary Based on 14 case studies of highly effective therapies and the reasons they succeeded less frequently than they could, we propose a variety of steps to improve the health care system of the U.S.A. Whatever proposal emerges from current national debates until innovations are shown to be safe and effective, they should not be supported; when slightly better technologies are much more expensive than other good ones we need to consider appropriate choices carefully; simplified billing and bookkeping would reduce our costs; when a technology is rapidly introduced cautionnary measures may be needed; tracking immunization and repairing their omissions requires a new system; educational programs such as seen effective in hypertension should be applied in other areas such as vaccination; in organ transplantation the nation should consider “presumed consent”; our payment system sometimes creates perverse incentives and therefore needs review; and the preferences of the public in allocation of health resources need to be discovered once the public is informed about the issues. Research supported by Andrew W. Mellon Foundation.  相似文献   
25.
Beryllium is the strongest of the lightweight metals. Used primarily in military applications prior to the end of the Cold War, beryllium is finding new applications in many commercial products, including computers, telecommunication equipment, and consumer and automotive electronics. The use of beryllium in nondefense consumer applications is of concern because beryllium is toxic. Inhalation of beryllium dust or vapor causes a chronic lung disease in some individuals at concentrations as low as 0.01 microg/m3 in air. As beryllium enters wider commerce, it is prudent to ask what risks this might present to the general public and to workers downstream of the beryllium materials industry. We address this question by evaluating the potential for beryllium exposure from the manufacturing, use, recycle, and disposal of beryllium-containing products. Combining a market study with a qualitative exposure analysis, we determine which beryllium applications and life cycle phases have the largest exposure potential. Our analysis suggests that use and maintenance of the most common types of beryllium-containing products do not result in any obvious exposures of concern, and that maintenance activities result in greater exposures than product use. Product disposal has potential to present significant individual risks, but uncertainties concerning current and future routes of product disposal make it difficult to be definitive. Overall, additional exposure and dose-response data are needed to evaluate both the health significance of many exposure scenarios, and the adequacy of existing regulations to protect workers and the public. Although public exposures to beryllium and public awareness and concern regarding beryllium risks are currently low, beryllium risks have psychometric qualities that may lead to rapidly heightened public concern.  相似文献   
26.
To quantify the health benefits of environmental policies, economists generally require estimates of the reduced probability of illness or death. For policies that reduce exposure to carcinogenic substances, these estimates traditionally have been obtained through the linear extrapolation of experimental dose-response data to low-exposure scenarios as described in the U.S. Environmental Protection Agency's Guidelines for Carcinogen Risk Assessment (1986). In response to evolving scientific knowledge, EPA proposed revisions to the guidelines in 1996. Under the proposed revisions, dose-response relationships would not be estimated for carcinogens thought to exhibit nonlinear modes of action. Such a change in cancer-risk assessment methods and outputs will likely have serious consequences for how benefit-cost analyses of policies aimed at reducing cancer risks are conducted. Any tendency for reduced quantification of effects in environmental risk assessments, such as those contemplated in the revisions to EPA's cancer-risk assessment guidelines, impedes the ability of economic analysts to respond to increasing calls for benefit-cost analysis. This article examines the implications for benefit-cost analysis of carcinogenic exposures of the proposed changes to the 1986 Guidelines and proposes an approach for bounding dose-response relationships when no biologically based models are available. In spite of the more limited quantitative information provided in a carcinogen risk assessment under the proposed revisions to the guidelines, we argue that reasonable bounds on dose-response relationships can be estimated for low-level exposures to nonlinear carcinogens. This approach yields estimates of reduced illness for use in a benefit-cost analysis while incorporating evidence of nonlinearities in the dose-response relationship. As an illustration, the bounding approach is applied to the case of chloroform exposure.  相似文献   
27.
This study evaluates the dose-response relationship for inhalation exposure to hexavalent chromium [Cr(VI)] and lung cancer mortality for workers of a chromate production facility, and provides estimates of the carcinogenic potency. The data were analyzed using relative risk and additive risk dose-response models implemented with both Poisson and Cox regression. Potential confounding by birth cohort and smoking prevalence were also assessed. Lifetime cumulative exposure and highest monthly exposure were the dose metrics evaluated. The estimated lifetime additional risk of lung cancer mortality associated with 45 years of occupational exposure to 1 microg/m3 Cr(VI) (occupational exposure unit risk) was 0.00205 (90%CI: 0.00134, 0.00291) for the relative risk model and 0.00216 (90%CI: 0.00143, 0.00302) for the additive risk model assuming a linear dose response for cumulative exposure with a five-year lag. Extrapolating these findings to a continuous (e.g., environmental) exposure scenario yielded an environmental unit risk of 0.00978 (90%CI: 0.00640, 0.0138) for the relative risk model [e.g., a cancer slope factor of 34 (mg/kg-day)-1] and 0.0125 (90%CI: 0.00833, 0.0175) for the additive risk model. The relative risk model is preferred because it is more consistent with the expected trend for lung cancer risk with age. Based on statistical tests for exposure-related trend, there was no statistically significant increased lung cancer risk below lifetime cumulative occupational exposures of 1.0 mg-yr/m3, and no excess risk for workers whose highest average monthly exposure did not exceed the current Permissible Exposure Limit (52 microg/m3). It is acknowledged that this study had limited power to detect increases at these low exposure levels. These cancer potency estimates are comparable to those developed by U.S. regulatory agencies and should be useful for assessing the potential cancer hazard associated with inhaled Cr(VI).  相似文献   
28.
We discuss the issue of using benchmark doses for quantifying (excess) risk associated with exposure to environmental hazards. The paradigm of low-dose risk estimation in dose-response modeling is used as the primary application scenario. Emphasis is placed on making simultaneous inferences on benchmark doses when data are in the form of proportions, although the concepts translate easily to other forms of outcome data.  相似文献   
29.
目的:比较社区卫生服务中心及各级医院常见手术费用;社区卫生服务中心手术是否便捷、低耗,有无保留的必要。方法:调研南京市社区卫生服务中心及各级医院常见手术的单病种费用,社区卫生服务中心与各级医院的费用做统计分析比较。结果:社区卫生服务中心单病种手术平均住院费用明显低于与各级医院。结论:从经济学的角度分析,各级医院手术费用差别很大,在规范和安全的前提下,社区卫生服务中心保留基本的手术功能是符合社区居民需求和社区卫生服务自身发展需要的。  相似文献   
30.
福州市社区空巢老年人健康状况调查   总被引:9,自引:0,他引:9  
目的了解空巢老年人的健康现状及其影响因素,为老龄工作提供科学依据。方法2002年4~5月进行入户调查,采用分层整群抽取福州市鼓楼、台江、仓山三个区60岁及以上的社区老年人,共得到有效样本1767例,其中空巢老人696名。空巢老人躯体健康、生活自理能力(ADL)、经济状况、精神健康、社会健康5个维度的健康状况及其影响因素的调查是本次研究的主要内容。结果福州市社区空巢老年人占老年人总体比例的39%,其中男性多于女性;由logistic检验得出空巢老年人健康状况受年龄、性别、原职业、是否赞成非家庭养老方式、锻炼程度等因素的影响。结论倡导空巢老年人形成良好的生活饮食习惯与自我保健意识,加强对空巢老年人慢性病的防治,丰富老年人的精神生活、社会生活,提高对空巢老年人经济支持,完善社区为老服务,从而改善空巢老年人的健康状况。  相似文献   
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