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排序方式: 共有332条查询结果,搜索用时 15 毫秒
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目的 探讨中西药和膳食补充剂相关的药物性肝损伤(DILI)患者肝组织病理学特点。方法 2017年1月1日~2020年12月31日上海中医药大学附属曙光医院诊治的DILI患者38例,均接受肝活检和结构化专家观点评估法(SEPO)评估,并验证药物性肝损伤组织病理学评分(DILI-PSS)的诊断价值。结果 38例DILI患者应用化学药品和生物制品14例(36.8%)、中草药12例(31.6%)、化学药品和生物制品合用中草药9例(23.7%)、膳食补充剂3例(7.9%);肝组织脂肪变性20例(52.6%),胆汁淤积22例(57.9%),胆管损伤15例(39.4%),嗜酸性粒细胞浸润11例(28.9%),肝细胞花环9例(23.7%),肉芽肿6例(15.8);少量坏死11例(28.9%),较多25例(65.8%),大量2例(5.3%);应用DILI-PSS诊断的AUROC为0.775 (95%CI:0.669~0.880,P<0.05),其灵敏度为81.6%,特异度为65.8%。结论 DILI患者肝组织有一定的病理学特征表现,应用DILI-PSS可能有助于诊断DILI,需要进一步研究。  相似文献   
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We examine the influence of harmful alcohol use on mental health using a flexible two‐step instrumental variables approach and household survey data from nine countries of the former Soviet Union. Using alcohol advertisements to instrument for alcohol, we show that problem drinking has a large detrimental effect on psychological distress, with problem drinkers exhibiting a 42% increase in the number of mental health problems reported and a 15% higher chance of reporting very poor mental health. Ignoring endogeneity leads to an underestimation of the damaging effect of excessive drinking. Findings suggest that more effective alcohol polices and treatment services in the former Soviet Union may have added benefits in terms of reducing poor mental health. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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王雨田  何玉成  闫桂权  杨雪 《中草药》2020,51(6):1669-1676
中药材专业市场交易量逐渐下降,产地市场交易成为趋势。研究产地市场整合程度有利于了解中药材市场的运行情况,对于合理规划中药材生产和提高市场效率具有重要意义。选取大宗中药材金银花、枸杞子、板蓝根和太子参研究中药材市场整合程度,利用2013—2019年价格指数,运用协整检验、误差修正模型和格兰杰因果检验进行实证分析。结果表明,我国中药材产地市场长期整合程度较高;中药材产地市场的短期整合程度远不及长期整合程度。为此提出4点政策建议:完善中药材价格信息平台、打造非道地产区中药材优质品牌、加快建成中药材质量追溯体系和建设中药材现代物流体系。  相似文献   
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基于脑电信号的情感识别,对于相关情感疾病的诊断与治疗有着重要的临床和科研意义。如何有效地提取特征,提高识别率,减少计算时间是研究的重点。从研究脑通道间定向信息交互的角度出发,结合对瞬时因果效应的补偿算法,提出以变尺度符号化补偿传递熵(VSSCTE)为特征的情感分析方法,并以此构建情感因效性脑网络,使用网络测度与ReliefF特征优化选择算法进行通道选择。结果显示,在使用DAEP数据集中处理后的127个压力状态和125个平静状态的数据时,较传统的二元传递熵方法,VSSCTE的特征提取方法在压力和平静情感二分类上的准确率提升约15%,达到96.74%;进行脑电通道优化后,当通道数由32个降至15个时,分类准确率仅下降约2%(分类准确率为94.36%),计算时间从51.27 s降至23.84 s。所提出的VSSCTE脑电特征提取方法可以有效分析情感变化时脑区之间的信息交互,为情感分析和计算提供新的思路。  相似文献   
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目的 观察1型糖尿病(T1DM)患儿静息态fMRI双侧海马效应连接的变化。方法 对1型T1DM患儿(n=18,T1DM组)和健康儿童(n=13,对照组)行静息态fMRI数据采集,以双侧海马为ROI进行Granger因果分析。结果 与对照组比较,以左侧海马为种子点,T1DM组左侧海马对双侧额中回、岛盖部额下回、三角部额下回、中央后回、辅助运动区、脑岛、前扣带和旁扣带脑回、内侧扣带和旁扣带脑回、缘上回,左侧内侧额上回、中央前回,右侧背外侧额上回的外向流显著减弱;以右侧海马为种子点,T1DM组右侧海马对双侧辅助运动区、内侧扣带和旁扣带脑回,左侧的额中回、岛盖部额下回、三角部额下回、内侧额上回、中央后回、前扣带和旁扣带脑回、缘上回外向流显著减弱。结论 T1DM患儿海马功能可能受到损伤,导致额叶、辅助运动皮层、扣带皮层对海马信息的提取能力减弱;与右侧海马相比,左侧海马可能对认知处理的参与度更高;海马外向流减弱对T1DM相关认知损害具有早期警示作用。  相似文献   
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Oral lichen planus (OLP) is a variant of lichen planus (LP), a common chronic mucocutaneous inflammatory disease. Cutaneous lesions of LP are self‐limiting, but OLP lesions are non‐remissive, alternating periods of exacerbation and quiescence, and only symptomatic treatments exist for OLP. The precise etiology and pathogenesis of OLP are hardly understood, which is a major obstacle to the development of new therapeutics for this disease. OLP is considered a T‐cell‐mediated inflammatory disease. Although various antigens have been considered, what actually triggers the inflammatory response of T cells is unknown. Suggested predisposing factors include genetic factors, stress, trauma, and infection. The aim of this review was to determine whether microbial infection can cause OLP. We first reviewed the association between OLP and microbial factors, including viral, fungal, and bacterial infections. In addition, each microbial factor associated with OLP was assessed by modified guidelines of Fredricks and Relman to determine whether it establishes a causal relationship. In conclusion, no microbial factor yet fulfills the guidelines to establish the causality of OLP. By focusing on the unclarified issues, however, the potential roles of microbial factors in the pathogenesis of OLP will be soon elucidated.  相似文献   
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Abstract

Perhaps no other topic in risk analysis is more difficult, more controversial, or more important to risk management policy analysts and decision-makers than how to draw valid, correctly qualified causal conclusions from observational data. Statistical methods can readily quantify associations between observed variables using measures such as relative risk (RR) ratios, odds ratios (OR), slope coefficients for exposure or treatment variables in regression models, and quantities derived from these measures. Textbooks of epidemiology explain how to calculate population attributable fractions, attributable risks, burden-of-disease estimates, and probabilities of causation from relative risk (RR) ratios. Despite their suggestive names, these association-based measures have no necessary connection to causation if the associations on which they are based arise from bias, confounding, p-hacking, coincident historical trends, or other noncausal sources. But policy analysts and decision makers need something more: trustworthy predictions – and, later, evaluations – of the changes in outcomes caused by changes in policy variables. This concept of manipulative causation differs from the more familiar concepts of associational and attributive causation most widely used in epidemiology. Drawing on modern literature on causal discovery and inference principles and algorithms for drawing limited but useful causal conclusions from observational data, we propose seven criteria for assessing consistency of data with a manipulative causal exposure–response relationship – mutual information, directed dependence, internal and external consistency, coherent causal explanation of biological plausibility, causal mediation confirmation, and refutation of non-causal explanations – and discuss to what extent it is now possible to automate discovery of manipulative causal dependencies and quantification of causal effects from observational data. We compare our proposed principles for causal discovery and inference to the traditional Bradford Hill considerations from 1965. Understanding how old and new principles are related can clarify and enrich both.  相似文献   
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