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Journal of Thrombosis and Thrombolysis - The extended use of thromboprophylaxis with direct oral anticoagulants (DOACs) for more than 30 days has been evaluated as an alternative...  相似文献   
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目的 探讨智慧课堂融合任务驱动教学法在《医学影像学》教学中的应用效果。方法 选取2018 年9 -12 月大连医科大学2015 级本科临床专业4 个班的学生,分为研究组64 名学生(接受智慧课堂融合任务驱动教学法教学),对照组64 名学生(接受传统授予式教学法教学)。教学结束后,通过随堂测试评价教学效果,内容包括学生客观考核与主观考评。应用SPSS 19.0 软件对数据进行统计分析。结果 研究组学生客观考核成绩(82.39±9.59)高于对照组(70±11.55),差异具有统计学意义(P < 0.05);研究组学生在激发学习兴趣(82.9% 比10.6%)、培养影像诊断思维能力及阅片技能(91.3% 比5.6%)、培养独立思考与解决问题能力(88.5% 比7.8%)、培养自主学习与科研创新思维(86.7% 比9.2%)均高于对照组学生,具有统计学意义(P < 0.01);两组学生对智慧课堂融合任务驱动教学法改革的认同感或对教学改革的期待(93.3% 比85.4%)无统计学意义。结论 智慧课堂融合任务驱动教学法,提高《医学影像学》教学质量显著,有助于激发学生的学习兴趣,培养学生的影像学诊断思维模式、良好的阅片习惯及技能。  相似文献   
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Background

Prohibition of tobacco sales to minors is a provision of the World Health Organization Framework Convention on tobacco control. This measure is effective to reduce youth tobacco use, if the legislation adopted is properly implemented and enforced. Through the examples of France and Quebec, the objective of this study is to compare legislative frameworks prohibiting tobacco sales to minors, their enforcement, and possible impact on underage smoking.

Methods

Identification of legislative instruments, reports from public health authorities, and articles addressing the focused question was performed trough Medline and Google.

Results

Selling tobacco products to minors under 18 years of age has been banned by the law since 1998 in Quebec and 2009 in France. In 2011, in France for individuals aged 17, compliance with the law was 15%. In 2017 in France, 94% of 17-year-old daily smokers regularly bought their cigarettes in a tobacco store. Law enforcement controls and sanctions are non-existent. In 2013 in Quebec, 23% of underage smoking students usually bought their own cigarettes in a business. The compliance rate with the prohibition law rose from 37% in 2003 to 92.6% in 2017. An approach of underage “mystery shoppers” attempting to purchase tobacco products and dedicated inspectors has been implemented, and progressive sanctions are applied in case of non-compliance. In 2013, 12.2% of Quebec high school students and, in 2017, 34.1% of French 17 year olds reported using tobacco products in the last 30 days.

Conclusion

Only an improved law enforcement, through the training of tobacco retailer's, inspections and effective deterrent penalties for non-compliance, leads to an effective legislative measure in terms of public health.  相似文献   
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Dysplastic naevi (DN) are benign lesions with atypical features intermediate between that of common melanocytic naevi (CMN) and malignant melanoma (MM). Debate remains over whether DN represent progressive lesions from CMN. Through gene expression profiling and analysis of molecular gene signatures, our study revealed progressive increases in immune activation and regulation, along with pathways implicated in melanomagenesis, from CMN to DN to MM. Using criteria of 1.5‐fold change and false discovery rate ≤0.05, we found differential expression of 7186 probes (6370 unique genes) with the largest difference detected between DN and MM from the standpoint of genomic melanoma progression. Despite progressive increases in the T‐helper type 1 (Th1)‐inducing gene (IL‐12), RT‐PCR indicated impaired Th1 or cytotoxic T‐cell response (decreased IFN‐γ) in MM. Concordantly, our results indicated progressive increases in molecular markers associated with regulatory T cells, exhausted T cells and tolerogenic dendritic cells, including detection of increased expression of suppressor of cytokine signalling 3 (SOCS3) in dendritic cells associated with MM. All together, our findings suggest that the increased immunosuppressive microenvironment of melanoma may contribute to unhampered proliferation of neoplastic cells. In addition, the detection of increased markers associated with tolerogenic dendritic cells in MM suggests that targeting these suppressive immune cell types may represent an alternative avenue for future immunotherapy.  相似文献   
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