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31.
基于百度指数关键词检索频度分析,选取9个医疗器械相关关键词,分析关键词的大众关注度与媒体关注度,以及关键词检索人群属性,如性别、年龄、职业和地区等的分布情况,并据此提出具有针对性的意见。  相似文献   
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Individuals with ASD often demonstrate superior performance on embedded figures tasks (EFTs). We investigated visual scanning behaviour in children with ASD during an EFT in an attempt replicating a previous study examining differences in visual search behaviour. Twenty-three children with, and 31 children without an ASD were shown 16 items from the Figure-Ground subtest of the TVPS-3 while wearing an eye tracker. Children with ASD exhibited fewer fixations, and less time per fixation, on the target figure. Accuracy was similar between the two groups. There were no other noteworthy differences between children with and without ASD. Differences in visual scanning patterns in the presence of typical behavioural performance suggest that any purported differences in processing style may not be detrimental to cognitive performance and further refinement of the current methodology may lead to support for a purported advantageous cognitive style.  相似文献   
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PurposeThe aim of this study was to assess the effect of overnight shifts (ONS) on radiologist fatigue, visual search pattern, and diagnostic performance.MethodsThis experimental study was approved by the institutional review board. Twelve radiologists (five faculty members and seven residents) each completed two sessions: one during a normal workday (“not fatigued”) and another in the morning after an ONS (“fatigued”). Each radiologist completed the Swedish Occupational Fatigue Inventory. During each session, radiologists viewed 20 bone radiographs consisting of normal and abnormal findings. Viewing time, diagnostic confidence, and eye-tracking data were recorded.ResultsSwedish Occupational Fatigue Inventory results demonstrated worsening in all five variables (lack of energy, physical exertion, physical discomfort, lack of motivation, and sleepiness) after ONS (P < .01). Overall, participants demonstrated worse diagnostic performance in the fatigued versus not fatigued state (P < .05). Total viewing time per case was longer when fatigued (35.9 ± 25.8 seconds) than not fatigued (24.8 ± 16.3 seconds) (P < .0001). Total viewing time per case was longer for residents (P < .05). Mean total fixations generated during the search increased by 60% during fatigued sessions (P < .0001). Mean time to first fixate on the fracture increased by 34% during fatigued sessions (P < .0001) and was longer for residents (P < .01). Dwell times associated with true- and false-positive decisions increased, whereas those with false negatives decreased.ConclusionsAfter ONS, radiologists were more fatigued with worse diagnostic performance, a 45% increase in view time per case, a 60% increase in total gaze fixations, and a 34% increase in time to fixate on the fracture. The effects of fatigue were more pronounced in residents.  相似文献   
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Background and ObjectiveTo combine the results of the best scientific evidence in order to compare the effects of cardiac resynchronization therapy (CRT) in heart failure patients with atrial fibrillation (AF) and in sinus rhythm (SR) and to determine the effect of atrioventricular nodal ablation in AF patients.MethodsThe electronic databases PubMed, B-On and Cochrane CENTRAL were searched, and manual searches were performed, for randomized controlled trials and cohort studies up to November 2012. The endpoints analyzed were all-cause and cardiovascular mortality and response to CRT.ResultsWe included 19 studies involving 5324 patients: 1399 in AF and 3925 in SR. All-cause mortality was more likely in patients with AF compared to patients in SR (OR=1.69; 95% CI: 1.20–2.37; p=0.002). There were no statistically significant differences in cardiovascular mortality (OR=1.36; 95% CI: 0.92–2.01; p=0.12). AF was associated with an increased likelihood of lack of response to CRT (OR=1.41; 95% CI: 1.15–1.73; p=0.001). Among subjects with AF, ablation of the atrioventricular node was associated with a reduction in all-cause mortality (OR=0.42; 95% CI: 0.22–0.80; p=0.008), cardiovascular death (OR=0.39; 95% CI: 0.20–0.75; p=0.005) and the number of non-responders to CRT (OR=0.30; 95% CI: 0.10–0.90; p=0.03).ConclusionsThe presence of AF is associated with increased likelihood of all-cause death and non-response to CRT, compared to patients in SR. However, many patients with AF benefit from CRT. Atrioventricular nodal ablation appears to increase the benefits of CRT in patients with AF.  相似文献   
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《Social neuroscience》2013,8(5-6):560-576
Previous behavioral research has revealed a positivity effect that occurs with aging, with older adults focusing more on positive information and less on negative emotional stimuli as compared to young adults. Questions have been raised as to whether this effect exists in the rapid detection of information or whether it operates only at later stages of processing. In the present study, we used eye-tracking and neuroimaging methodologies to examine whether the two age groups accomplished the detection of emotional information on a visual search task using the same mechanisms. Eye-tracking results revealed no significant age differences in detection or viewing time of emotional targets as a function of valence. Despite their general similarity in task performance, neuroimaging results revealed an age-related valence-based reversal in medial prefrontal cortex (MPFC) activity, with detection of negative compared to positive targets activating the MPFC more for younger adults, and detection of positive compared to negative targets activating the MPFC more for older adults. These results suggest that age-related valence reversals in neural activity can exist even on tasks that require only relatively automatic processing of emotional information.  相似文献   
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