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61.
Cognitive science has converged in many ways with cognitive psychology, but while also maintaining a distinctive interdisciplinary nature. Here we further characterize this existing state of the field before proposing how it might be reconceptualized toward a broader and more distinct, and thus more stable, position in the realm of sciences. 相似文献
62.
It is argued that simulating psychological processes by means of computer models is a valuable technique to increase our understanding of adolescent developmental processes. Modelling offers possibilities to test hypotheses that cannot be reached by designing empirical studies only and it allows us to investigate adolescent development as the complex and non-linear process that it is. 相似文献
63.
《Parkinsonism & related disorders》2014,20(11):1263-1267
IntroductionDisease progression in Parkinson's disease is often calculated in data from cross-sectional studies, where a severity score (e.g. UPDRS-motor score) is divided by disease duration. While this intuitively may seem a plausible approach, it is uncertain if these rates are similar to those calculated from longitudinal data. The aim of this study is to examine if progression rates calculated according to both methods yield the same results.MethodsWe calculated two progression rates in data from the PROPARK study: one where last follow-up SPES/SCOPA motor and activities-of-daily-living scores were divided by disease duration, and one in which baseline motor and activities-of-daily-living scores were subtracted from data collected at last follow-up, and where the difference was divided by the time that passed between both assessments. We subsequently calculated the rank order correlation between both approaches.ResultsWe found that progression rates calculated from cross-sectional data are 1.5–2 times higher than those calculated from longitudinal data, and that the correlation between both methods is <0.50.ConclusionProgression rates calculated from cross-sectional data not only overestimate actual progression, but also yield a different rank order. We also discuss potential explanations for the discrepancy between both methods and argue that the method of calculating progression rates in data from cross-sectional studies in PD should not be used. 相似文献
64.
《European journal of cancer (Oxford, England : 1990)》2014,50(17):2983-2993
BackgroundUsing potential surrogate end-points for overall survival (OS) such as Disease-Free- (DFS) or Progression-Free Survival (PFS) is increasingly common in randomised controlled trials (RCTs). However, end-points are too often imprecisely defined which largely contributes to a lack of homogeneity across trials, hampering comparison between them. The aim of the DATECAN (Definition for the Assessment of Time-to-event End-points in CANcer trials)-Pancreas project is to provide guidelines for standardised definition of time-to-event end-points in RCTs for pancreatic cancer.MethodsTime-to-event end-points currently used were identified from a literature review of pancreatic RCT trials (2006–2009). Academic research groups were contacted for participation in order to select clinicians and methodologists to participate in the pilot and scoring groups (>30 experts). A consensus was built after 2 rounds of the modified Delphi formal consensus approach with the Rand scoring methodology (range: 1–9).ResultsFor pancreatic cancer, 14 time to event end-points and 25 distinct event types applied to two settings (detectable disease and/or no detectable disease) were considered relevant and included in the questionnaire sent to 52 selected experts. Thirty experts answered both scoring rounds. A total of 204 events distributed over the 14 end-points were scored. After the first round, consensus was reached for 25 items; after the second consensus was reached for 156 items; and after the face-to-face meeting for 203 items.ConclusionThe formal consensus approach reached the elaboration of guidelines for standardised definitions of time-to-event end-points allowing cross-comparison of RCTs in pancreatic cancer. 相似文献
65.
喻斌 《中国中医药现代远程教育》2008,6(7):716-716
《药理实验方法学》是一门以实验研究为主要内容的一门学科,因此此门功课在教学中有自己的一些特点。在教学中应特别要注重对学生创新思维、综合科研能力的培养,为学生以后的科研工作大好基础。注重加强教与学的双向信息反馈以增加教师和学生的双向交流。同时有效利用多媒体技术能极大的活跃课堂气氛。 相似文献
66.
W. B. F. Brouwer N. J. A. van Exel B. van Gorp W. K. Redekop 《Quality of life research》2006,15(6):1005-1021
The societal perspective in economic evaluations dictates that costs and effects of informal care are included in the analyses.
However, this incorporation depends on practically applicable, reliable and valid methods to register the impact of informal
care. This paper presents the conceptualisation and a first test of the CarerQol instrument, aimed at measuring care-related
quality of life in informal caregivers. The instrument combines the information density of a burden instrument (encompassing
seven important burden dimensions) with a valuation component (a VAS scale for happiness). The instrument was tested in a
Dutch sample of heterogeneous caregivers (n = 175) approached through regional caregiver support centres. This first test describes the feasibility as well as convergent
and clinical validity of the CarerQol instrument. The seven burden dimensions related well with differences in VAS scores.
In all instances, the average CarerQol-VAS scores decreased as the severity of problems increased. Multivariate analyses showed
that the seven burden dimensions explained 37–43% of the variation in CarerQol-VAS scores, depending on the model used. The
CarerQol seems a promising new instrument to register the impact of informal caregivers in economic evaluations. 相似文献
67.
This study examined the efficiency of different time series analysis techniques to extract information on the coupling of spontaneous phasic physiological responses. We compared four bivariate approaches, cross-spectral, cross-covariance, cross-covariance with prewhitening, and dynamic factor analysis, in their ability to yield unbiased estimates of (a) shared variance, (b) covariance, (c) strength of relationship, and (d) interchannel time-lag in empirical and simulated interbeat interval-electrodermal activity (IBI-EDA) time series. All methods produced similar estimates of the grand-averaged IBI-EDA dynamics, but only the measures of covariance produced reliable and unbiased estimates of the interindividual distribution of IBI-EDA coupling. We conclude that the extraction of phasic response patterns during continuous and unrestricted experimental situations may considerably facilitate psychophysiological research. 相似文献
68.
Disabilities impact individuals across all demographic groups, resulting in multiculturalism within the culture of disability. Several years ago researchers within the area of disabilities studies noted a tendency to overlook the cultural heterogeneity
within their samples of individuals with disabilities and called for greater awareness. It is unclear to what degree research
psychologists as well as other disciplines have heeded the call to adopt a cultural lens when studying populations with disabilities.
A methodological and content review of sexuality and disability studies was conducted to evaluate how researchers are conceptualizing
and presenting cultural data. Recent articles in four leading disability journals from 2002 to 2006 were reviewed, yielding
54 studies and over 11,000 participants. The content analysis found tremendous inconsistency in the collection style and reporting
of cultural information (e.g. gender, race, ethnicity, socio-economic status, sexual orientation). Results indicate ethnic
minorities may continue to be under-recruited and understudied in the disability and sexuality literature. 相似文献
69.
目的:建立一套稳定的利用MALDI-TOF MS进行恶性肿瘤血清蛋白质组学分析方法。方法:通过对血清样品采集、保存条件的优化,标准蛋白质的选择,样品的前处理和上样分析等多种条件的优化,确定各个相关参数的选择。结果:经实验条件的比较与优化发现,血液样本采集1 h后经2000 g离心分离血清,分装成若干份,冻存于-80℃冰箱备用,样本前处理方法参照说明书进行;质谱分析条件为应用线性模式,采集范围800-10,000Da,利用多点采集的方法,8点采集,累加至400shots,保存备用。结论:通过优化实验条件,初步建立了利用MALDI-TOF MS进行血清蛋白质组学分析的一整套研究方法,生物质谱分析结果的整体稳定性和重复性可满足统计学和临床医学实验室分析要求。 相似文献
70.
作者采用癌灶多点取材法,对食管癌患考癌细胞DNA含量进行了分析。结果表明,患者癌细胞DNA异倍体和多异倍体检出率和随机一点取材法相比,分别增加了50%和3.5倍。用该取材法还可以检测患者的DNA倍体异质性和DNA干系的分布情况。 相似文献