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Phenomenon: Medical students, like physicians, experience negative emotions such as frustration when interacting with some patients, and many of these interactions occur for the first time during clinical clerkships. Students receive preclinical training in the social and behavioral sciences, often including learning about “difficult patient” interactions, yet little is known about their desire for training during clinical education. We explored students’ strategies in these difficult clinical interactions, whether they felt prepared by the curriculum, and what support they would have liked. These data inform proposed strategies for supporting clinical learning. Approach: We interviewed 4th-year students about interactions with patients toward whom they felt negative emotions and sought to identify strategies and supports needed in these interactions. Interviews ended when theoretical sufficiency was achieved. We used qualitative content analysis to organize strategies into themes about areas benefiting from curricular supports. We mapped students’ desired curricular support examples to cognitive apprenticeship teaching methods—modeling, coaching, reflection, scaffolding, exploration, and articulation—and aligned them with traditional pedagogical techniques. Findings: We interviewed 26 medical students (44 volunteered/180 invited). Their strategies formed five themes: finding empathy (with a subtheme of focusing on social determinants of health), using learned communication approaches, anticipating challenging interactions, seeking support, and considering it an opportunity for more responsibility. Students described ideal clinical teaching, including postinteraction debriefs with an emphasis on validating their emotional reactions and challenges. Students mentioned all cognitive apprenticeship teaching methods, most prominently modeling (observing supervisors in such interactions) and supported oral reflection. They also identified a need for faculty and resident development to enact these teaching methods. Insights: Although students use some learned strategies in interactions in which they feel negative emotions toward patients, they desire more preparation and support during their clinical rotations. Their desires map to traditional pedagogical techniques and to methods of cognitive apprenticeship. Our findings point to the need to use these techniques to enhance clinical learning for students who experience emotionally challenging patient interactions.  相似文献   
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A prospective cohort study was performed in 50 patients with dengue haemorrhagic fever (DHF) to determine the potential role of the contact activation system and factor XI activation (intrinsic pathway) in the coagulation disorders in DHF. To establish whether TAFI (thrombin-activatable fibrinolysis inhibitor) was involved in the severity of the coagulation disorders, the TAFI antigen and activity levels were also determined. Markers of contact activation (kallikrein--C1-inhibitor complexes), the intrinsic pathway of coagulation (factor XIa--C1-inhibitor complexes) and TAFI were measured and correlated to thrombin generation markers (thrombin--anti-thrombin complexes (TAT), prothrombin fragment 1+2 (F1+2)) and a marker for fibrinolysis [plasmin--alpha 2--anti-plasmin complexes (PAP)]. Activation of the intrinsic pathway of coagulation was clearly demonstrated by elevated levels of factor XIa--C1-inhibitor complexes, without evidence of contact activation, reflected by undetectable kallikrein--C1-inhibitor complexes. Both TAFI antigen and activity levels were decreased in all patients, which may contribute to the severity of bleeding complications in DHF because of the impaired capacity of the coagulation system to protect the fibrin clot from fibrinolysis. These findings in a human viral infection model are in accordance with earlier findings in bacterial sepsis.  相似文献   
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Contrast enhanced cross sectional echocardiography is a new method for the real-time evaluation of regional myocardial perfusion. Two patients with a history of anteroseptal myocardial infarction and echocardiographically detected septal dyskinesia were examined by this new method. The first patient had two severe stenoses of the left anterior descending coronary artery and normal echocontrast opacification of the interventricular septum caused by collaterals from the right coronary artery. The second patient had good patency of left anterior descending coronary artery and no septal opacification. Thus contrast enhanced cross sectional echocardiography can be used to assess the importance of collateral blood flow in the myocardium.  相似文献   
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We have infused recombinant factor VIIa into patients with hereditary factor VII deficiency with marked reductions in plasma concentrations of factor IX activation peptide (FIXP), factor X activation peptide (FXP), and prothrombin activation fragment F1+2. These investigations show substantial elevations in these markers of coagulation activation and thereby demonstrate that the factor VII-tissue factor pathway is largely responsible for the activation of factor IX as well as factor X in the basal state (ie, the absence of thrombosis or provocative stimuli). We have administered a monoclonal antibody purified factor IX concentrate to individuals with hemophilia B. These studies show an increase in the plasma levels of FIXP that were initially greatly decreased, but no change in FXP or F1+2. We have also infused highly purified factor VIII concentrate into patients with hemophilia A. The data demonstrate no significant changes in the plasma concentrations of FXP and F1+2. The above observations indicate that factor IXa generated by the factor VII-tissue factor pathway is unable to activate factor X under basal conditions. Based upon the above findings, we outline a model of blood coagulation system function under basal conditions, and suggest a process by which the generation of factor Xa and thrombin might be accelerated during normal hemostasis and in the setting of thrombotic disorders.  相似文献   
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The knowledge and skills that are required for radiological image interpretation are not well documented, even though medical imaging is gaining importance. This study aims to develop a comprehensive framework of knowledge and skills, required for two-dimensional and multiplanar image interpretation in radiology. A mixed-method study approach was applied. First, a literature search was performed to identify knowledge and skills that are important for image interpretation. Three databases, PubMed, PsycINFO and Embase, were searched for studies using synonyms of image interpretation skills or visual expertise combined with synonyms of radiology. Empirical or review studies concerning knowledge and skills for medical image interpretation were included and relevant knowledge and skill items were extracted. Second, a preliminary framework was built and discussed with nine selective experts in individual semi-structured interviews. The expert team consisted of four radiologists, one radiology resident, two education scientists, one cognitive psychologist and one neuropsychologist. The framework was optimised based on the experts comments. Finally, the framework was applied to empirical data, derived from verbal protocols of ten clerks interpreting two-dimensional and multiplanar radiological images. In consensus meetings adjustments were made to resolve discrepancies of the framework with the verbal protocol data. We designed a framework with three main components of image interpretation: perception, analysis and synthesis. The literature study provided four knowledge and twelve skill items. As a result of the expert interviews, one skill item was added and formulations of existing items were adjusted. The think-aloud experiment showed that all knowledge items and three of the skill items were applied within all three main components of the image interpretation process. The remaining framework items were apparent only within one of the main components. After combining two knowledge items, we finally identified three knowledge items and thirteen skills, essential for image interpretation by trainees. The framework can serve as a guideline for education and assessment of two- and three-dimensional image interpretation. Further validation of the framework in larger study groups with different levels of expertise is needed.  相似文献   
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Objective: To compare sun protection by Australian‐born and migrant mothers of three‐year‐old children. Methods: Australian‐born and migrant mothers taking part in the Environments for Healthy Living prospective birth‐cohort study were asked standard questions about their child's sun protection. Children were given a skin cancer susceptibility score based on grandparents' ethnic origin. Logistic regression was used to estimate odds ratios (ORs) to measure the association of sun protection of children according to mothers' migrant status adjusted for socio‐demographic characteristics. Results: A total of 613 Australian‐born and 224 migrant mothers of three‐year‐old children were studied. Mothers who had migrated less than four years ago were more likely to allow their three‐year‐old to spend more than two hours outdoors between 10 am and 3 pm compared to Australian‐born mothers (OR=2.80, 95%CI 1.20–6.57). Mothers from high latitude countries (>45 degrees) were more likely to apply sunscreen to their child than those from lower latitude countries (OR=3.15, 95%CI 1.03–9.61). Conclusions and implications: Strategies should aim to increase general awareness about the need for sun protection of young children, and recent migrants should be alerted to the harms of excessive sun exposure.  相似文献   
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Objective : To outline some of the key issues for injury‐related data linkage studies in Australia and describe potential applications of data linkage for injury surveillance and research. Methods : Narrative review of data linkage capacity and injury‐related data collection quality in Australia. Results : The establishment of national and state‐based data linkage centres in Australia has been a great leap forward for data linkage capacity for injury research. However, there are still limitations of using data linkage for injury surveillance and research. These are highlighted in the form of key perils and pitfalls, with examples provided. There is still much to be gained for injury research by using data linkage techniques to enhance the information available across the injury continuum, but data quality issues should always be acknowledged. Conclusions : Obtaining authorisation to link injury data collections for national research remains cumbersome. Streamlining of the application process is needed to ensure that injury research is able to be conducted in a timely fashion. Data quality and data linkage rates need to be considered when interpreting research findings. Implications : Streamlining of the application process for research that involves linking data collections would help ensure that research is conducted in a timely fashion.  相似文献   
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