灰关联聚类分析方法碘乏病防治效果评价中的应用

本文以灰色系统理论为基础,创立了碘缺乏病防治效果评价分析方法,并通过实例证实其评价方法的简洁性、灵活性和有效性,其结论可为指导防治工作提供依据。     

Risk Assessment of Virus in Drinking Water

The reevaluation of drinking water treatment practices in a desire to minimize the formation of disinfection byproducts while assuring minimum levels of public health protection against infectious organisms has caused it to become necessary to consider the problem of estimation of risks posed from exposure to low levels of microorganisms, such as virus or protozoans, found in treated drinking water. This paper outlines a methodology based on risk assessment principles to approach the problem. The methodology is validated by comparison with results obtained in a prospective epidemiological study. It is feasible to produce both point and interval estimates of infection, illness and perhaps mortality by this methodology. Areas of uncertainty which require future data are indicated.     

An Analysis of Changes in the Risk of Mortality from Chronic Obstructive Lung Disease, 1968-1977

Nonlinear hazard models are used to examine temporal trends in the age-specific mortality risks of chronic obstructive lung diseases for the U.S. population. These hazard functions are fit to age-specific mortality rates for 1968 and 1977 for four race/sex groups. Changes in the parameters of these models are used to assess two types of differences in the age pattern of the rates between 1968 and 1977. The first measure of trend in the age-specific mortality rates is the temporal change in the proportionality constant in the function used to model their age variation. By allowing only this proportionality parameter to vary between 1968 and 1977, it is possible to determine an age-constant percentage increase or decrease. The second measure reflects the absolute displacement in terms of years of life of the fitted mortality curves for the two time points. This second index can be interpreted as the acceleration or deceleration of mortality risks over the life span, i.e., the number of years that is needed for mortality rates to achieve the same level as in the comparison group. The analysis showed that the age changes in chronic obstructive lung disease mortality rates differed by race/sex group and for both measures of change over the period. Adjustment of the fitted curves for the effects of individual variability in risk was significant for three of four groups.     

Learning Experiences of Older Volunteers in a Community-based Social Program for People with Dementia

Abstract

This qualitative study aimed to explore older adults’ perspectives on volunteering in an activity-based social program for community-dwelling people with dementia called Stepping Stones. Semi-structured interviews were individually conducted with eight older adults who had volunteered in Stepping Stones. Interpretative phenomenological analysis was used to analyze interview data. Four themes related to learning experiences of older volunteers in Stepping Stones emerged. These themes include (a) self-growth and confidence in working with people with dementia; (b) understanding dementia, people with dementia, and needed support for people with dementia and their families; (c) desire not to develop dementia, while recognizing that anything can happen in old age; and (d) exercising person-centered approaches and taking on advocacy roles. Findings suggest that older volunteers gain feelings of personal growth and confidence in working with people with dementia, better understanding, and enhanced attitudes toward people with dementia through volunteering in an activity-based social program for people with dementia. Older adults will be able to fill the needs of community programs for people with dementia, while experiencing benefits from volunteering and learning in later life. Further research is needed to examine to what extent having previous dementia experiences make their experiences and learning different.     

Joint coverage probability in a simulation study on continuous-time Markov chain parameter estimation

Parameter dependency within data sets in simulation studies is common, especially in models such as continuous-time Markov chains (CTMCs). Additionally, the literature lacks a comprehensive examination of estimation performance for the likelihood-based general multi-state CTMC. Among studies attempting to assess the estimation, none have accounted for dependency among parameter estimates. The purpose of this research is twofold: (1) to develop a multivariate approach for assessing accuracy and precision for simulation studies (2) to add to the literature a comprehensive examination of the estimation of a general 3-state CTMC model. Simulation studies are conducted to analyze longitudinal data with a trinomial outcome using a CTMC with and without covariates. Measures of performance including bias, component-wise coverage probabilities, and joint coverage probabilities are calculated. An application is presented using Alzheimer's disease caregiver stress levels. Comparisons of joint and component-wise parameter estimates yield conflicting inferential results in simulations from models with and without covariates. In conclusion, caution should be taken when conducting simulation studies aiming to assess performance and choice of inference should properly reflect the purpose of the simulation.     

当前呼吸内科临床实习中的问题与对策

临床实习是将医学生培养成为临床医生最重要的环节之一。但现阶段医学生在呼吸内科的临床实习中面临着一些问题,如实习管理松懈、带教老师轻视教学、医学实习生面临“考研”、“择业”压力忽视呼吸内科实习,以及呼吸内科学科自身的一些原因等。文章分析了影响当前呼吸内科实习质量“教”与“学”的多方面因素,提出解决呼吸内科临床实习的一些建议。     

Using a grey relational analysis in an improved Grunow–Finke assessment tool to detect unnatural epidemics

The Grunow–Finke epidemiological assessment tool (GFT) has several limitations in its ability to differentiate between natural and man-made epidemics. Our study aimed to improve the GFT and analyze historical epidemics to validate the model. Using a gray relational analysis (GRA), we improved the GFT by revising the existing standards and adding five new standards. We then removed the artificial weights and final decision threshold. Finally, by using typically unnatural epidemic events as references, we used the GRA to calculate the unnatural probability and obtain assessment results. Using the advanced tool, we conducted retrospective and case analyses to test its performance. In the validation set of 13 historical epidemics, unnatural and natural epidemics were divided into two categories near the unnatural probability of 45%, showing evident differences (p < 0.01) and an assessment accuracy close to 100%. The unnatural probabilities of the Ebola virus disease of 2013 and Middle East Respiratory Syndrome of 2012 were 30.6% and 36.1%, respectively. Our advanced epidemic assessment tool improved the accuracy of the original GFT from approximately 55% to approximately 100% and reduced the impact of human factors on these outcomes effectively.     

中华鳖皮肤溃烂病的病原研究

从病鳖肝脏、颈、腿部皮肤溃烂处分离得到菌株M－3、M－6、J－8、J－10株细菌。经人工感染试验证明这四株菌为鳖皮肤溃烂病的病原菌。对菌体形态特征、培养特性和生理生化反应的鉴定证明J-8、J-10为温和气单胞菌（Aeromonassobira），M-3、M-6为摩根氏菌（Morganella，mor－ganii）。     

鸡传染性法氏囊病非免疫器官病理组织学观察

将 4 0只 1日龄雅康蛋用公雏饲喂至 30日龄 ,随机分为感染组和对照组 ,感染组鸡用传染性法氏囊野毒进行点眼、滴鼻和肌注 ,并于感染后 4 8h、72h、96h剖杀 ,取非免疫器官按常规石蜡切片 ,H·E染色 ,光镜观察。结果表明 :雏鸡感染传染性法氏囊病毒后 ,非免疫器官均发生了不同程度的病理变化 ,且随感染时间的延长 ,其病变程度越严重 ,其中以肝、肾的实质细胞变性、坏死较为严重 ,并伴有炎症时的血管反应及间质增生