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91.
We comment on the target article by Weingardt (this issue), which discusses recent advances in instructional design and technology (IDT) and their implications for dissemination of evidence-based practices. These arguments are extended to the topic of psychological intervention design, and possibilities for new intervention structures are briefly explored. Finally, comments are offered on maintaining a careful balance between technological and social processes in the effort to promote the dissemination of innovative and evidence-based psychological procedures.  相似文献   
92.
Publication Guidelines for Heart Rate Studies in Man   总被引:1,自引:0,他引:1  
Publication guidelines are provided for the collection, quantification, and analysis of heart rate data.  相似文献   
93.
Constrained optimization recently has been implemented in the LISREL software package, allowing formulation of parent-offspring transmission models in a simple and efficient manner. A reverse path model of parental transmission is described within the LISREL framework for application to twin and/or adoptive family data. The model incorporates genetic and environmental parameter constraints arising from assortative mating and cultural transmission. An illustration of the LISREL model is given using measures obtained from twins and parents involving fear of social criticism.  相似文献   
94.
利用CT扫描及CAD技术建立腰椎活动节段的有限元模型   总被引:9,自引:0,他引:9  
目的 :探讨腰椎活动节段有限元模型的建立。方法 :选取一正常自愿者L4~L5节段为研究对象 ,通过CT扫描、图像数字化处理及计算机辅助设计建立了腰椎活动节段的有限元模型 ,通过Super SAP有限元分析软件包对模型进行了应力分析。结果 :建立了L4~L5活动节段的有限元模型 ,并分析了生理载荷下腰椎活动节段不同组成部分的应力分布。结论 :为腰椎活动节段有限元模型的建立提供了一种简便、准确的方法 ,为分析和研究该模型在各种情况下的生物力学表现创造了条件  相似文献   
95.
Perceptual Speed and IQ Are Associated Through Common Genetic Factors   总被引:1,自引:0,他引:1  
Individual differences in inspection time explain about 20% of IQ test variance. To determine whether the association between inspection time and IQ is mediated by common genes or by a common environmental factor, inspection time and IQ were assessed in an extended twin design. Data from 688 participants from 271 families were collected as part of a large ongoing project on the genetics of adult brain function and cognition. The sample consisted of a young adult cohort (mean age 26.2 years) and an older adult cohort (mean age 50.4 years). IQ was assessed with the Dutch version of the WAIS-3R. Inspection time was measured in the so-called -paradigm, in which a subject is asked to decide which leg of the -figure is longest at varying display times of the -figure. The number of correct inspections per second (i.e., the reciprocal of inspection time) was used to index perceptual speed. For Verbal IQ and Performance IQ, heritabilities were 85% and 69%, respectively. For perceptual speed, 46% of the total variance was explained by genetic variance. No differences in heritability estimates across age cohorts or sexes were found. Across the whole sample, a significant phenotypic correlation was found between perceptual speed and Verbal IQ (0.19) and between perceptual speed and Performance IQ (0.27). These correlations were entirely due to a common genetic factor that accounted for 10% of the genetic variance in verbal IQ and for 22% of the genetic variance in performance IQ. This factor is hypothesized to reflect the influence of genetic factors that determine axonal myelination in the central nervous system.  相似文献   
96.
The mortality experience of a large refinery cohort (1937-1978) was examined by dividing it into three subcohorts according to hire dates: those hired before 1940, those hired during the period 1940-1945, and those hired after 1945. These three periods are approximately equivalent to before, during, and after World War II and span a total hiring period of more than 75 years. The results showed that a substantial portion of the cohort (3,330 or 27%) had been recruited during 1940-1945, and they contributed 980 or 28% of the total deaths. However, their mortality experience was quite different from the rest. A series of significant increases were seen among the external causes for accidents, suicide, and homicide. In terms of overall mortality and in contrast to the rest of the cohort, no "healthy worker effect" was seen (SMR = 1.00). They also showed increases in several types of cancer including cancers of the pancreas and prostate and leukemia. These unusual experiences cannot be explained either on the basis of their war-related deaths or on their period of employment (one-half were terminated within 1 year from date of hire), and data is insufficient to separate the role of hiring practices or their socioeconomic status. However, their life-styles were probably quite different judged from the fact that alcoholism-related deaths were increased as much as fivefold. Almost two-thirds of the total deaths occurred among 4,080 workers in the before 1940 subcohort. Further, the 5,117 workers of the after-1945 subcohort contributed only 5% of the total deaths. Thus, the results of the original refinery cohort (1937-1978) primarily reflect the experience of those employees hired before 1940. Given the same cohort method (historical prospective), cohort results vary widely according to different study designs, and this has implications for "generalizable" risk assessment or risk projections. A prospective study of new hires with 30 years of follow-up is rather inefficient because it would yield only a small number of deaths, with a strong healthy worker effect. The same is true for studies based on active workers with a short period of follow-up. Studies based on time of hire, however, provide a means for controlling time-related occupational exposures.  相似文献   
97.
Equations have been developed that relate the concentration (or a parameter directly proportional to concentration, such as optical absorbance) of a weakly ionizable solute in a water-immiscible phase, in equilibrium with an aqueous phase, to the pH of the aqueous phase, the partition coefficient of the unionized solute and the phase volume ratio. These relationships have been used in the design of experimental methods for determining partition coefficients, which require measurement of solute concentration in only one phase. Data obtained in this way permit ready recognition of deviations from assumptions made in the development of the model; these assumptions include insolubility of the ionized solute in the water-immiscible phase and lack of interaction between buffer components and solute. Conditions for optimal liquid—liquid extraction of weakly ionizable solutes are more easily recognized. With these techniques, the negative logarithm of the acid dissociation constant (pKa) and the logarithm of the octanol—water partition coefficient (log P) have been measured for warfarin (pKa = 5.15 ± 0.04; log P = 2.82 ± 0.06), strychnine (pKa = 8.29 ± 0.02; log P = 2.23 ± 0.04), phenol (pKa = 9.88 ± 0.02; log P = 1.75 ± 0.05), procaine (pKa = 8.11 ± 0.04; log P = 1.10 ± 0.08), and ephedrine (pKa = 9.92 ± 0.01; log P = 1.65 ± 0.04) at 21°C.  相似文献   
98.
【目的】 总结科技期刊封面设计流程管理模式并探讨其中的相关问题,为同行提供经验借鉴。【方法】 从版面、设计风格等方面对科技期刊封面图片的特征进行归纳。以中国激光杂志社期刊封面为例,总结封面设计流程管理模式,探讨封面设计过程中的相关问题。【结果】 期刊应对封面的主题策划、生产流程、版权保护等方面进行有效的流程管理。此外,就封面设置及风格、元素文化、版权意识、与设计公司合作等问题进行思考总结。【结论】 科技期刊可通过合理的封面设计流程,将科技与艺术融合,更准确地传播前沿科技成果,并弘扬中国传统文化。  相似文献   
99.
【目的】 探索中文科技期刊封面发展的可行途径。【方法】 分析我国科技期刊封面设计现状以及制约中文科技期刊封面发展的瓶颈,并以《协和医学杂志》为例,介绍其封面设计团队的建立和运营经验,展示封面设计在其期刊品牌建设中发挥的作用。【结果】 中文科技期刊在编委人才梯队化建设过程中,通过主动发现和利用青年人才,能够建立稳定的封面设计团队,呈现高水平的封面设计,进而显著提升期刊品牌影响力。【结论】 封面质量建设对提升期刊品牌影响力具有重要作用,紧密结合中文期刊自身发展特点,善于借助可利用的优势资源,是中文科技期刊突破封面发展瓶颈的可行途径。  相似文献   
100.
目的 分析中药治疗糖尿病肾脏疾病(DKD)随机对照试验中结局指标的使用情况和其他试验设计要素,为中药治疗DKD临床试验的设计及核心指标集的构建提供依据。方法 计算机检索知网、万方、维普、中国生物医学等7个医学数据库及2个临床试验注册中心(clinicaltrials.gov、chinadrugtrials.org.cn)近5年收录的中药治疗DKD随机对照试验,运用Cochrance手册对纳入的文献进行偏倚风险评估,对结局指标及其他试验设计要素进行统计与分析。结果 共纳入97项随机对照试验(RCTs),包含5项试验注册方案,研究发现,97项研究总体偏倚风险较高;DKD Ⅲ期(36项,41.38%)和气阴两虚兼血瘀证(16次,26.23%)为应用最多的DKD分期及中医证型;92项RCTs的疗程最多96周,最少2周,其中52项(56.52%)研究疗程为12周;92项RCTs及5项注册试验共采用152种结局指标,使用1 040次,共分为8大类,实验室检查(血液)、实验室检查(尿液)、临床疗效、中医证候积分、生活质量量表、生命体征、其他指标及其他事件,应用频率较高的依次是血肌酐(68次,70.10%)、临床有效率(55次,56.70%)、空腹血糖(51次,52.58%)、尿素氮(48次,49.48%)、总胆固醇(47次,48.45%)、24 h尿蛋白定量(43次,44.33%)等;56项RCTs及2项注册试验共采用安全性指标53种,频数227次,使用频率较高的依次是,不良反应(49次,84.48%)、肝功能(28次,48.28%)、血常规(24次,41.38%)、心电图(17次,29.31%)、尿常规(14次,24.14%);10项RCTs及5项注册试验报告了主要结局指标;54项RCTs报告了临床有效率指标。结论 目前中药治疗DKD的RCTs结局指标设计尚不规范,未来应积极构建突显出中医药特色的核心结局指标集,提升临床研究的质量,提高试验结果的应用价值。  相似文献   
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