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In this paper, we argue that understanding and addressing the problem of poor-quality medical products requires a more interdisciplinary approach than has been evident to date. While prospective studies based on rigorous standardized methodologies are the gold standard for measuring the prevalence of poor-quality medical products and understanding their distribution nationally and internationally, they should be complemented by social science research to unpack the complex set of social, economic, and governance factors that underlie these patterns. In the following sections, we discuss specific examples of prospective quality surveys and of social science studies, highlighting the value of cross-sector partnerships in driving high-quality, policy-relevant research in this area.  相似文献   
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介绍了《医疗器械监督管理条例》(以下简称《条例》)的法律属性与地位,详细分析了2021年版《条例》修订确立的风险管理、全程管控、科学监管、社会共治以及严格责任等监管原则,指出2021年版《条例》在将医疗器械注册人制度确立为医疗器械行业基本制度的同时规定了多项旨在满足临床急需的管理制度。阐述了2021年版《条例》的修订对产业创新发展和产业整体安全产生的深远影响,对医疗器械法规研究以及行业产业发展具有重要的意义。  相似文献   
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《Drug discovery today》2022,27(1):280-291
Positron emission tomography (PET) is an extensively used nuclear functional imaging technique, especially for central nervous system (CNS) and oncological disorders. Currently, drug development is a lengthy and costly pursuit. Imaging with PET radiotracers could be an effective way to hasten drug discovery and advancement, because it facilitates the monitoring of key facets, such as receptor occupancy quantification, drug biodistribution, pharmacokinetic (PK) analyses, validation of target engagement, treatment monitoring, and measurement of neurotransmitter concentrations. These parameters demand careful analyses for the robust appraisal of newly formulated drugs during preclinical and clinical trials. In this review, we discuss the usage of PET imaging in radiopharmaceutical development; drug development approaches with PET imaging; and PET developments in oncological and cardiac drug discovery.  相似文献   
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BackgroundStressors among nursing students arise from both academic activities and clinical placement. Understanding how nursing students perceive academic and clinical stressors and the clinical learning environment could help develop useful approaches to reducing levels of stress and contribute to the maintenance of a good learning environment. There is a paucity of studies that investigated associations between the clinical learning environment and the stress of nursing students.ObjectivesTo investigate the relationship between the perception of the clinical learning environment and stress in nursing students; to compare the perception of the clinical learning environment and stress in terms of the year and terms of the organization of supervision.DesignCross-sectional correlation studySettingsUniversityParticipantsThe sample consisted of 155 nursing students in the bachelor's degree program. During the four academic years, students of individual years of the bachelor's study program were included in the study after completing all clinical placements in a given academic year.MethodsThe following instruments were used for the data collection: Clinical Learning Environment, Supervision and Nurse Teacher evaluation scale, Perceived Stress Scale; Physio-Psycho-Social Response Scale and Coping Behaviour Inventory. Correlation analysis and multiple linear regression analysis using stepwise methods were used to determine the relationships between the variables.ResultsThe clinical learning environment is a strong predictor of students' perceptions of stress related to teachers and nursing staff. Types and degrees of stressful events during clinical practice varied between years of study. The experience with supervision was related to the overall perception of the clinical learning environment, but not to the students' physio-psychosocial status, types of stressful events during clinical practice and coping behaviors. Also, the differences in the students' physio-psychosocial status were not significant in terms of individual years of study and method of supervision.ConclusionsThere is a significant relationship between the clinical learning environment and the perception of academic stress. The attitude of the teacher and the medical staff can thus be important in influencing the level of stress in nursing students.  相似文献   
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摘要:目的 本文对甘肃省2018-2020年食源性疾病监测中分离的致泻大肠埃希菌从年度、季度、性别、年龄分布进行分析,并对分离株耐药状况进行研究,为由致泻大肠埃希菌引起的食源性疾病的防控及抗生素的使用提供政策和依据。方法 按照《食源性疾病监测工作手册》从食源性疾病病例监测样本中分离得到大肠埃希菌株,PCR方法进行分型,采用微量肉汤稀释法进行药敏试验。结果 2018-2020年甘肃省由致泻大肠埃希菌引起的食源性疾病呈下降趋势,患病率男性大于女性,19~45岁组大于其他年龄组。致泻大肠埃希菌对氨苄西林的耐药率最高(78.8%),对复方磺胺甲恶唑、头孢唑林、四环素3种抗生素的耐药率超过40%,对亚胺培南、头孢西丁、头孢他啶3种抗生素的耐药率低于10%。致泻大肠埃希菌的多重耐药率为69.8%。5种型别的致泻大肠埃希菌中EAEC占比为62.2%,各型别对氨苄西林、头孢唑林和头孢噻肟的抗生素敏感性存在显著性差异(P<0.05)。结论 甘肃省食源性疾病中致泻大肠埃希菌耐药形势严峻,各个市州应当完善食源性疾病中致泻大肠埃希菌的监测工作,并对抗生素的使用进行控制。  相似文献   
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An ovine iliac vein thrombosis model was devised to test a wall-contacting rotational thrombectomy device. Thrombosis was successfully induced in 9 sheep with an average clot length of 31 mm ± 12 and >60% vessel occlusion on angiography. The thrombus was subsequently removed, maintaining normal intraoperative pulmonary arterial pressure (5.9 mm Hg ± 3.6) and complete distal reperfusion after thrombectomy. Additionally, the sheep were without signs of vascular trauma or embolic complications on gross necropsy and histopathologic analysis. The findings from this study support the use of an ovine iliac deep vein thrombosis model for testing of a lower extremity thrombectomy device.  相似文献   
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