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本篇综述总结了帕金森病的诊断、鉴别诊断和病程监测的各领域的生物学标记物的研究进展。其中重点介绍了神经影像学和生物化学领域的生物学标记物,也是当前研究较为成熟的两大领域。神经影像学标记物以多巴胺能影像及非多巴胺能影像为代表,生物化学标记物为包括a一突触核蛋白在内的多种蛋白和激素,两者的结合能够有效提高疾病诊断的特异性和灵敏性。同时文章还介绍了当前研究的热点——帕金森病的前驱诊断手段,即在疾病典型的运动症状和非运动症状出现前便可预测帕金森病的诊断手段。  相似文献   
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Research progress in the anxiety disorders is predicated on a useful classification system. In this paper, we review the reliability and validity data for theDiagnostic and Statistical Manual of Mental Disorders, 3rd ed. (DSM-III) anxiety disorders and discuss the salient issues associated with both the conceptualization of anxiety disorders and the diagnostic criteria offered in the DSM-III. It is concluded that the diagnostic reliability for these disorders is, overall, satisfactory. A dearth of validity data, however, hinders progress in both the diagnosis and the treatment of the anxiety disorders. Nevertheless, the DSM-III work group has proposed several changes in the diagnostic criteria for the anxiety disorders. We find some of these proposed changes helpful in that they clarify current diagnostic criteria; changes in diagnostic criteria that alter the basic classification schema, however, seem to be premature.Preparation of this paper was supported in part by MIMH Research Grant 1368.On sabbatical leave from Indiana State University.  相似文献   
65.
从系统论分析肾病综合症的诊断治疗   总被引:1,自引:0,他引:1  
分析系统论方法主要基本原则在肾病综合症诊治中的指导性作用.揭示在医学科学研究中自觉、主动地运用辩证思维方法和系统论科学方法,可以拓展研究的新思路,为疾病的诊治提供最佳方案,对促进和指导医学研究发展有极其重要的意义.  相似文献   
66.
摘要:相对于参数化的方法,本研究根据题目测量模式关系开发出ICC指标,并提出基于理想得分的ICC指标法进行Q矩阵估计。Monte Carlo模拟研究与实证研究发现(1)基于理想得分ICC指标法估计Q矩阵具有很好的效果,当属性个数越少、基础题个数越多,估计效果越好。(2)相对于以往方法——D2统计量的方法,ICC-IR法效果更好,并且是一种非参数化的方法,计算简单快捷。(3)实证数据分析表明,ICC-IR法估计的Q矩阵在模型拟合度上也优于D2统计量方法。  相似文献   
67.
To provide more refined diagnostic feedback with collateral information in item response times (RTs), this study proposed joint modelling of attributes and response speed using item responses and RTs simultaneously for cognitive diagnosis. For illustration, an extended deterministic input, noisy ‘and’ gate (DINA) model was proposed for joint modelling of responses and RTs. Model parameter estimation was explored using the Bayesian Markov chain Monte Carlo (MCMC) method. The PISA 2012 computer-based mathematics data were analysed first. These real data estimates were treated as true values in a subsequent simulation study. A follow-up simulation study with ideal testing conditions was conducted as well to further evaluate model parameter recovery. The results indicated that model parameters could be well recovered using the MCMC approach. Further, incorporating RTs into the DINA model would improve attribute and profile correct classification rates and result in more accurate and precise estimation of the model parameters.  相似文献   
68.
The maximum likelihood classification rule is a standard method to classify examinee attribute profiles in cognitive diagnosis models (CDMs). Its asymptotic behaviour is well understood when the model is assumed to be correct, but has not been explored in the case of misspecified latent class models. This paper investigates the asymptotic behaviour of a two-stage maximum likelihood classifier under a misspecified CDM. The analysis is conducted in a general restricted latent class model framework addressing all types of CDMs. Sufficient conditions are proposed under which a consistent classification can be obtained by using a misspecified model. Discussions are also provided on the inconsistency of classification under certain model misspecification scenarios. Simulation studies and a real data application are conducted to illustrate these results. Our findings can provide some guidelines as to when a misspecified simple model or a general model can be used to provide a good classification result.  相似文献   
69.
Atypical forgetting functions have been demonstrated in several recent studies of delayed matching to sample, in which experimental conditions are altered partway through the retention interval. The forgetting functions are atypical in that accuracy or discriminability is not always a negatively accelerated monotonic function of increasing retention interval duration, but may increase at later times in the retention interval. Atypical forgetting functions reflect changes in levels of discrimination. A switch from a lower level to a higher level of discrimination, or vice versa, can occur at any time in the retention interval. The behavioral theories of remembering proposed by Nevin, Davison, Odum, and Shahan (2007), and White and Brown (2014), offer quantitative predictions of forgetting functions that differ in intercept or slope. Both theories are able to account for atypical forgetting functions, by assuming time‐independent changes in the mediating effect of attending to sample and comparison stimuli (in Nevin et al.'s model) or in the direct effect of the context of reinforcement of the conditional discrimination (in White & Brown's model). Despite differences in their main assumptions, the theories have an edge over any theory that assumes that forgetting is time‐dependent.  相似文献   
70.
Zebrafish (Danio rerio) is a common vertebrate animal model in biomedical research and is a promising species for studying how genes interact with environmental factors in determining behavior. The present study investigated how reinforcement parameters affect zebrafish behavior by assessing response acquisition with delayed reinforcement, which has been studied with other species (e.g., rats, pigeons, humans, etc.) but not with zebrafish. Twenty‐four experimentally naïve subjects were exposed to a tandem fixed‐ratio 1 differential‐reinforcement‐of‐other‐behavior x‐s schedule of reinforcement, where x varied across subjects. There were six different delay‐to‐reinforcement durations and sets of four fish were assigned to each delay duration. All of the fish assigned to a 0‐, 0.5‐, or 1‐s delay acquired responding. Two fish acquired responding with a 3‐s delay and one fish appeared to have acquired it with a 6‐s delay although the latter result was less clear. None acquired responding with a 12‐s delay. These results suggest that zebrafish behavior is sensitive to delays to reinforcement and the time frame over which reinforcement is effective may be limited approximately to 6 s. This time frame is shorter than that found with other species. Practical and theoretical implications of the present finding are discussed.  相似文献   
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