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101.
Christopher C. Stahl Sarah A. Jung Alexandra A. Rosser Aaron S. Kraut Benjamin H. Schnapp Mary Westergaard Azita G. Hamedani Rebecca M. Minter Jacob A. Greenberg 《American journal of surgery》2021,221(2):369-375
BackgroundEntrustable Professional Activities (EPAs) contain narrative ‘entrustment roadmaps’ designed to describe specific behaviors associated with different entrustment levels. However, these roadmaps were created using expert committee consensus, with little data available for guidance. Analysis of actual EPA assessment narrative comments using natural language processing may enhance our understanding of resident entrustment in actual practice.MethodsAll text comments associated with EPA microassessments at a single institution were combined. EPA—entrustment level pairs (e.g. Gallbladder Disease—Level 1) were identified as documents. Latent Dirichlet Allocation (LDA), a common machine learning algorithm, was used to identify latent topics in the documents associated with a single EPA. These topics were then reviewed for interpretability by human raters.ResultsOver 18 months, 1015 faculty EPA microassessments were collected from 64 faculty for 80 residents. LDA analysis identified topics that mapped 1:1 to EPA entrustment levels (Gammas >0.99). These LDA topics appeared to trend coherently with entrustment levels (words demonstrating high entrustment were consistently found in high entrustment topics, word demonstrating low entrustment were found in low entrustment topics).ConclusionsLDA is capable of identifying topics relevant to progressive surgical entrustment and autonomy in EPA comments. These topics provide insight into key behaviors that drive different level of resident autonomy and may allow for data-driven revision of EPA entrustment maps. 相似文献
102.
Jessica E. Rabski Ashirbani Saha Michael D. Cusimano 《American journal of surgery》2021,221(2):388-393
BackgroundCompetency-based medical education requires evaluations of residents’ performances of tasks of the discipline (ie. entrustable professional activities (EPAs)). Using neurosurgical Faculty perspectives, this study investigated whether a sample of neurosurgical EPAs accurately reflected the expectations of general neurosurgical practice.MethodA questionnaire was sent to all Canadian neurosurgery Faculty using a SurveyMonkey® platform.ResultsThe proportion of respondents who believed the EPAs were representative of general neurosurgery competences varied significantly across all EPAs [47%–100%] (p < 0.0001). For 9/15 proposed EPAs, ≥75% agreed they were appropriate for general neurosurgery training and expected residents to attain the highest standard of performance. However, a range of 27–53% of the respondents felt the other six EPAs would be more appropriate for fellowship training and thus, require a lower standard of performance from graduating residents.ConclusionThe shift towards subspecialization in neurosurgery has implications for curriculum design, delivery and certification of graduating residents. 相似文献
103.
Tea is a famous beverage that is produced from leaves of Camellia sinensis. Amongst the six major tea categories in China, dark tea is the only one that involves microbial fermentation in the manufacturing process, which contributes unique flavors and functions for the tea. In the recent decade, the reports about the biofunctions of dark teas have increased rapidly. Therefore it may be the proper time to consider dark tea as one potential homology of medicine and food. In this viewpoint, our current understanding of the chemical constituents, biological activities and possible health beneficial effects of dark teas were introduced. Some future directions and challenges to the development perspectives of dark teas were also discussed. 相似文献
104.
目的:观察高良姜、大高良姜、红豆蔻黄酮类成分对胃溃疡寒证大鼠环核苷酸水平及交感神经-肾上腺轴的影响,探讨3味山姜属中药温热药性的物质基础。方法:采用灌服冰知母水煎液与15%冰乙酸制备大鼠胃溃疡寒证模型,以干姜姜辣素为阳性对照,采用酶联免疫吸附试验(ELISA)法测定腺苷酸环化酶(AC)、磷酸二酯酶2(PDE2)、环磷酸腺苷(cAMP)、环磷酸鸟苷(cGMP)、促肾上腺皮质激素(ACTH)、多巴胺β羟化酶(D-β-H)含量。结果:与空白组比较,胃溃疡寒证模型组大鼠胃组织AC、cAMP含量及cAMP/cGMP比值显著降低,PDE2含量显著升高(P<0.01)。与模型组比较,高良姜、大高良姜、红豆蔻高低剂量组大鼠胃组织AC含量升高;高良姜、大高良姜、红豆蔻高低剂量组大鼠胃组织PDE2含量显著降低,cAMP含量、cAMP/cGMP比值显著升高(P<0.01或P<0.05)。结论:3味山姜属中药黄酮类成分通过调节胃溃疡寒证大鼠环核苷酸水平从而促进交感神经-肾上腺轴功能活动的作用,也体现出黄酮类成分药性温热。 相似文献
105.
Objective: To establish a method for directional screening of the cytotoxic components from the medicinal herb of Achnatherum inebrians by a combination of surface plasmon resonance (SPR) biosensor and chromatographic isolation technology.
Methods: Under the guidance of bioactive assessment based on binding abilities between objects and the α-Mannosidase (α-Man) target, the active components from different solvents extracts, different polar extraction parts and fractions were screened orderly and directionally using SPR. Components with a high binding ability to α-Man can be precisely oriented in a narrower fractions range and are easy to isolate. Three human cancer cells were used to evaluate the cytotoxic activity of component with the highest affinity to α-Man.
Results: Eight compounds were isolated and identificated from A. inebrians for the first time. Deoxyvasicinone possessed the highest affinity to α-Man among them. Moreover, deoxyvasicinone showed good effects on inhibited proliferation of human hepatoma cells HepG2 (IC50 = 5.7 μmol/L), human breast cancer cells MCF7 (IC50 = 7.21 μmol/L) and human lung cancer cells HCC827 (IC50 = 0.75 μmol/L), respectively. In particular, its inhibitory effect on HCC827 was stronger than the positive drug gefitinib (IC50 = 1.65 μmol/L).
Conclusion: A comprehensive strategy of directional screening potential cytotoxic components from herb based on biomolecular interaction and chromatography was established. Deoxyvasicinone as an effective anti-cancer component was initially isolated from A. inebrians. It is expected that this screening strategy could provide new perspectives for rapid screening and identification of active components from natural plants with the complex matrix. 相似文献
106.
107.
目的 建立清热消炎宁胶囊(Qingre Xiaoyanning Capsules,QXC)UPLC指纹图谱及多指标成分定量分析方法,结合化学模式识别技术对多批次制剂进行质量评价。方法 通过优化样品前处理及色谱检测方法,建立合适UPLC指纹图谱和含量测定条件。色谱柱为UPLC HSS T3柱(50 mm×2.1 mm,1.8μm);乙腈-0.1%甲酸水溶液为流动相梯度洗脱;检测波长280 nm;柱温40℃;体积流量0.5 mL/min。采用层次聚类分析(hierarchical cluster analysis,HCA)、主成分分析(principal component analysis,PCA)、正交偏最小二乘-判别分析(orthogonal partial least squares-discriminant analysis,OPLS-DA)和聚类热图分析对20批清热消炎宁胶囊进行质量评价。结果 清热消炎宁胶囊UPLC指纹图谱及含量测定方法学考察结果均符合测定要求,获得21个共有峰,运用对照品比对方式指认了7个色谱峰;20批样品的相似度均大于0.954,样品间一致性及稳定性良好;... 相似文献
108.
109.
随着全球化学品产量增加, 人群暴露及健康风险加重, 对化学品毒性测试和安全性评价提出更高的要求。21世纪毒性测试愿景和策略的提出大力推动了毒性测试的变革。新时代毒性测试通过运用新模型、新方法和新策略, 结合交叉学科和高新技术优势, 得到了长足发展。提高化学物毒性测试效率的同时, 也实现了更全面、多层次、高质量的数据获取和毒性评价, 为毒作用模式、毒作用机制和毒性通路的探索提供有力支持。本期重点号围绕当前毒性测试替代新方法, 邀请多位学者对高内涵分析、3D细胞培养技术、Ex vivo试验、单细胞测序、斑马鱼实验方法进行介绍和阐述, 以期为推动我国化学物毒性测试评估实现跨越发展开拓崭新思路。 相似文献
110.
目的 了解扬州市食品中化学污染物及有害因素的污染状况,确定风险因子的可能来源及分布,为食品安全防控工作提供数据依据。方法 依据每年扬州市《食品安全风险监测方案》,2015—2019年在扬州市辖区内采集食品样品,并进行相关化学污染物及有害因素的检测。结果 5年共检测23大类1 311份食品样品208个指标,样品合格率为97.79%;其中8类29份食品样品中13个指标超标,样品超标率为2.21%。不合格指标为蔬菜中农药残留和镉、茶叶和水果中农药残留、水产动物中总砷、藻类中铅、粉丝和油条中含铝添加剂、小麦制品中脱氧雪腐镰刀菌烯醇、蜂蜜中甲硝唑。结论 扬州市食品中的化学污染情况总体较好,但部分食品中仍存在污染物超标现象,应引起相关部门的重视。 相似文献