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1.
This report describes a model for identifying sets of teaching abilities considered to be effective for medical school teaching staff, based on roles teachers assume and functions they are expected to perform as instructors. The specification of these teaching abilities was the first step in the development of a comprehensive course on Medical Instruction at the Basic Institute of Medical and Agricultural Biology of the State University of Sao Paulo, Botucatu, Brazil, where the senior author is employed. The work was based on the assumption that medical school teachers are expected to assume a variety of teaching roles and that identification and specification of the abilities that define their roles can result in more effective and efficient teaching.  相似文献   
2.
Mental fatigue and task control: planning and preparation   总被引:6,自引:0,他引:6  
The effects of mental fatigue on planning and preparation for future actions were examined, using a task switching paradigm. Fatigue was induced by "time on task," with subjects performing a switch task continuously for 2 hr. Subjects had to alternate between tasks on every second trial, so that a new task set was required on every second trial. Manipulations of response-stimulus intervals (RSIs) were used to examine whether subjects prepared themselves for the task change. Behavioral measurements, event-related potentials (ERPs), and mood questionnaires were used to assess the effects of mental fatigue. Reaction times (RTs) were faster on trials in which no change in task set was required in comparison with switch trials, requiring a new task set. Long RSIs were used efficiently to prepare for the processing of subsequent stimuli. With increasing mental fatigue, preparation processes seemed to become less adequate and the number of errors increased. A clear poststimulus parietal negativity was observed on repetition trials, which reduced with time on task. This attention-related component was less pronounced in switch trials; instead, ERPs elicited in switch trials showed a clear frontal negativity. This negativity was also diminished by time on task. ERP differences between repetition and switch trials became smaller with increasing time on task.  相似文献   
3.
ONSET AND TERMINAL ORIENTING RESPONSES AS A FUNCTION OF TASK DEMANDS   总被引:1,自引:0,他引:1  
The frequency of response and trials to habituation of the electrodermal onset and terminal orienting response were manipulated as a function of discrimination tasks involving either stimulus content (pitch) or duration. There were no significant differences between the groups on either measure for onset ORs; however, the duration task group demonstrated more TORs and required a greater number of trials to habituate than the content task group. The results, interpreted in terms of the development of cortical models, supported Stern's suggestion that OR and TOR habituation are related to the content and duration of the stimulus respectively.  相似文献   
4.
Objectives:The objective was to investigate effects of timed bright light treatment on subjective and objective measures of sleepiness during three consecutive night shifts among hospital nurses.Methods:Thirty-five nurses were exposed to bright light (10,000 lux) and red dim light (100 lux) during three consecutive night shifts in a counter-balanced crossover trial lasting nine days, which included three days before and three days after the three night shifts. Light exposure for 30 minutes was scheduled between 02:00–03:00 hours on night 1, and thereafter delayed by one hour per night in order to delay the circadian rhythm. Subjective sleepiness was measured daily (heavy eyelids, reduced performance) and every second hour while awake (Karolinska Sleepiness Scale, KSS). Objective sleepiness (Psychomotor Vigilance Task, PVT) was measured at 05:00 hours during each night shift. Beyond nocturnal light exposure on the night shifts, no behavioral restrictions or recommendations were given at or off work.Results:Bright light treatment significantly reduced heavy eyelids during night shifts. However, results on KSS and PVT were unaffected by bright light. There were no differences in subjective sleepiness during the three days following the night shifts.Conclusions:This bright light treatment protocol did not convincingly reduce sleepiness among nurses during three consecutive night shifts. Nor did bright light impede the readaptation back to a day-oriented rhythm following the night shift period. Too few consecutive night shifts, inappropriate timing of light, and possible use of other countermeasures are among the explanations for the limited effects of bright light in the present study.  相似文献   
5.
Summary The central changes associated with a period of strength training have been investigated in a group of 32 young healthy volunteers. Subjects participated in one of three 12 week training programmes, which required different degrees of skill and coordination. Study 1 consisted of unilateral isometric training of the quadriceps with the contralateral leg acting as a control, the apparatus providing firm back support and a lap strap. In Study 2 training consisted of unilateral concentric leg-extension with back support and hand-grips. In Study 3 subjects performed bilateral leg-extension with no back support. Measurements of maximum voluntary isometric strength were made at 2–3 week intervals and a continual record was kept of the weights lifted in Studies 2 and 3. The largest increase in isometric force was seen for the trained leg in Study 1 (approximately 40%). There was no significant change in strength in the contralateral untrained leg. In Studies 2 and 3 there was a large increase in training weights (about 200%) associated with smaller increase in isometric force (15–20%). It is concluded that a large part of the improvement in the ability to lift weights was due to an increased ability to coordinate other muscle groups involved in the movement such as those used to stabilise the body. The importance of these findings for athletic training and rehabilitation is discussed.  相似文献   
6.
7.
A recommendation from the Social Work Task Force was that all employers of social workers should conduct a regular “health check” of the social work profession to learn from practice as part of a continuous cycle of improvement. This article documents how the London Borough of Tower Hamlets has gone about this. I describe the methodological and practical pathway we followed so that others can see what we did and why we did it. Like other busy social work offices, we had to set out a plan of methodological action in order that we achieved the learning from practice to inform our health check, and it is the planning work that is engaged with in this article. We have found that by involving and engaging our staff in the health check work, we have gained more than we had set out to find. An organisational commitment to act on what social workers have told us about practice is offering the senior management team new ideas about the best ways of delivering professional and reflective support mechanisms for staff. Learning from practice is now one of the core functions for the new Principal Social Worker.  相似文献   
8.
Recommendations for the frequency of mammography screening vary across several professional advisory groups. In 2009, the United States Preventive Services Task Force Guidelines reduced screening to biennially for women 50-74 years old. Drivers of this change were false-positive results and unnecessary biopsies, exposure to radiation, and treatment of cancers that would never develop. Despite the recommendation, surveys show that screening has actually increased since the change. A review of the individual woman's risk and a more balanced approach addressing both the benefits and harms of screening is required so that patients can make an informed choice.  相似文献   
9.
Having an advisor offers medical students many advantages, including increased likelihood of matching into their top choices. Interestingly, students who choose emergency medicine (EM) as a specialty are more likely to seek advising. However, finding and optimally utilizing an EM faculty advisor is often challenging for the medical student. In this article, we tackle the different ways to seek advising, including the ‘virtual advisor program’ implemented by the Society for Academic Emergency Medicine, the ‘e-Advisor Program’ instigated by the Clerkship Director in EM Group, the ‘member exclusive mentorship program’ of the Emergency Medicine Residency Association, as well as peer-based mentoring. More so, we discuss the consensus recommendations developed by the Student Advising Task Force to guide both students planning to apply to EM and their advisors to ensure high-caliber advising.  相似文献   
10.

Background

Vitiligo is an autoimmune disease with varying pathological features. Activation of the CCL20-CCR6 axis plays an important role in chronic inflammatory diseases. However, whether CCL20-CCR6 and Th1/17 cells are indicative of active vitiligo is unclear.

Objective

To investigate the potential role of CCL20 and the involvement of Th1/17 and Tc1/17 cells in the mechanism in vitiligo.

Methods

One hundred patients with vitiligo, and 20 healthy controls were included. The serum and blister fluid IL-17, IFN-γ, CCL20, and CXCL10 were studied using enzyme-linked immunosorbent assays. The numbers of Th1/17 cells and Tc1/17 cells in circulation were quantified using flow cytometry. CCR6 mRNA in peripheral blood mononuclear cells (PBMCs) was analyzed by real-time polymerase chain reaction and the protein level was confirmed by western blotting. CCR6 and CCL20 expression in lesions was analyzed by immunohistochemistry.

Results

The serum CCL20 level was significantly elevated in patients with vitiligo. The level of serum CCL20 was higher in active than in the stable stage, which correlated positively with the Vitiligo European Task Force spreading score and the Vitiligo Area Scoring Index score. Patients with active vitiligo had elevated numbers of circulating Th1/17 cells and Tc1/17 cells, and upregulated expression of CCR6 in PBMCs and lesions. After effective treatment, the level of CCL20 in sera and blister fluid was significantly decreased, as were the numbers of circulating Th1/17 cells and Tc1/17 cells.

Conclusion

CCL20 might be a vital biomarker of active vitiligo, and circulating Th1/17 and Tc1/17 cells are involved in the pathogenesis of vitiligo.  相似文献   
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