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Background: Deficits of attention or its control secondary to brain damage have been proposed as all or part of the underlying mechanisms for the linguistic impairments that characterise aphasia (Clark & Robin, 1995; Granier, Robin, Shapiro, Peach, & Zimba, 2000; McNeil, 1982, 1988; McNeil, Odell, & Tseng, 1991; Murray, Holland, & Beeson, 1997a; Tseng, McNeil, & Milenkovic, 1993). McNeil, Doyle, Hula, Rubinsky, Fossett, and Matthews (2004) developed a set of tasks to quantify the difficulty that normal listeners have in understanding the language production of persons with varying amounts of aphasia. In their dual-task study, a significant decrement was found in the visual–manual tracking accuracy of normal older individuals while concurrently listening to the connected language of a person with moderate, as compared to mild, aphasia. No performance costs were observed on the listening tasks across three tracking difficulty levels. Possible reasons for the unidirectional performance cost were speculated and the present study was designed to investigate one of them.Aims: Using the same story comprehension task used in the previous study and the same visual–manual tracking task, but increased in difficulty, this study sought to investigate whether the increased demands of the tracking task were sufficient to elicit a concurrent cost on story comprehension performance.Methods & Procedures: A total of 24 normal participants performed the tracking and story comprehension tasks concurrently and in isolation. Story retell performance was evaluated within subjects across two tracking difficulty levels (easy and hard) and tracking performance was evaluated between subjects across three story difficulty levels (no story, mild difficulty, and moderate difficulty).Outcomes & Results: Tracking performance varied significantly across story task difficulty in the easy tracking condition, with participants demonstrating better tracking performance in the mild story condition than in either the moderate story or no story conditions. None of the comparisons made with the harder tracking condition reached significance. There was no effect of tracking difficulty on story comprehension as measured by subsequent story retell performance.Conclusions: The findings from this study replicate the findings from the McNeil et al. (2004) study that these dual-tasks show a reliable cost of story difficulty on concurrent tracking performance. Contrary to predictions, no effect of tracking difficulty on story retell performance was found, despite the increased tracking difficulty used compared to the previous study. While this finding does diminish the probability that insufficient tracking task difficulty was the source of the unidirectional costs in the previous study, it leaves a number of alternative explanations for the findings viable and unaddressed.  相似文献   
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Patient selection criteria for echocardiography with sedation in children are not well defined. We attempted to identify predictors of unplanned repeat echocardiography with sedation. This was a single-center, case–control study of echocardiograms performed in children aged 1–36 months. Cases underwent unplanned repeat examinations with sedation, while controls did not. Patient variables and study indications were compared. Logistic regression identified the most significant predictors. Cases (n = 104, median time to repeat echocardiogram 17 days, median age 12.9 months) were older than controls (n = 212, median age 5.0 months, P < 0.001). Significantly more cases than controls had structural cardiac disease (64 vs. 23 %) and anatomic complexity ≥moderate (38 vs. 5 %, P < 0.001 for both). Cases more often had Kawasaki disease (11 vs. 2 %), and controls more often had murmur (56 vs. 11 %, P < 0.001 for both). Logistic regression identified age 6 months to <2 years (OR 3.26, 95 % CI 1.70–6.28, P < 0.001), Kawasaki disease (OR 5.20, 95 % CI 1.46–18.50, P = 0.01), and known pre-echocardiogram anatomic complexity ≥moderate (OR 3.99, 95 % CI 1.64–9.66, P = 0.002) as significant risk factors. An indication for murmur was protective (OR 0.32, 95 % CI 0.13–0.76, P = 0.01). We identified several risk factors for unplanned repeat echocardiography with sedation in children, including age 6 months to <2 years, higher anatomic complexity, and Kawasaki disease. Murmur was a protective factor. These results may help pediatric echocardiography laboratories establish criteria for sedation.  相似文献   
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Finestone HM, Blackmer J. Refusal to eat, capacity, and ethics in stroke patients: a report of 3 cases.Patients have the right to make decisions about their health care, including refusing a particular treatment or a life-sustaining activity such as eating. However, patients must be able to understand and appreciate the consequences of their actions. Brain injury caused by a stroke has the potential to affect people’s capacity to understand and appreciate their particular medical condition or its consequences. The purpose of this report was to describe the unique medical and ethical challenges presented by 3 rehabilitating stroke patients who refused to eat. Two patients had left-hemisphere strokes, with resultant aphasia. The third patient had a right-brain stroke and was able to state his position verbally but denied many of the consequences of his stroke. The refusal to eat and, therefore, possible impending death forced the attending physiatrist and rehabilitation team members to reevaluate the issue of capacity in the stroke patient. None of the patients died, and oral intake varied from fair to poor. This report elucidates the particular diagnostic, management, legal, and ethical issues surrounding the difficult but likely not uncommon issue of refusal to eat in stroke patients. It highlights the concept of capacity, which guides clinical decision making in such patients, and suggests specific clinical courses of action to take.  相似文献   
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PURPOSE: Photodynamic therapy (PDT) is a relatively new alternative modality for palliation of rectal cancer. Current source of light for PDT are laser systems that are expensive and not necessarily needed for PDT. We evaluated a new nonlaser light source for PDT, Versa-Light ® .METHODS AND RESULTS: In vitro PDT—CT26 murine colon carcinoma cells were incubated with aluminum phthalocyanine (AlPcS 4 ) for 48 hours and subjected to photoradiation using Versa-Light ® ,and viability was assessed. There was a significant decrease in viability of treated cells compared with controls. In vivo PDT—BALB/c mice were injected either subcutaneously or intrarectally with CT26 cancer cells. IP AlPcS 4 (2.5 mg/kg) was injected when tumors were visible. After 24 hours, mice were subjected to photoradiation. Massive tumor necrosis in response to PDT was observed. PDT also prolonged survival of treated mice. Patient treatment—A 70-year-old woman with recurrent local rectal carcinoma received intravenous Photofrin II ® (2 mg/kg). After 48 and 96 hours, she was subjected to direct photoradiation. After the first light session, there was complete macroscopic disappearance of the tumor. Biopsies up to 10 weeks after the treatment showed no cancer cells in the treated area. Sixteen weeks later, a randomized biopsy from previous tumor site showed carcinoma cells. CONCLUSIONS: We believe that Versa-Light ® ,is a good light source for PDT. It was effective in both in vitro and animal studies. It can also be safely used for clinical PDT.Supported by the Roni Udassin Memorial Fund of the Israel Cancer Society.  相似文献   
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Conjugate gaze deviation is associated with acute ischemic stroke (AIS), although previously only measured on a 2D plane. The current study evaluates 3D imaging efficacy to assess conjugate gaze deviation and correlate direction and strength of deviation to neuro-clinical findings.A retrospective analysis of 519 patients who had CT scans for suspected AIS at our institution. Direction and angle of eye deviation were calculated based on 2D axial images. Volumetric reconstruction of CT scans allowed for calculation of 3D conjugate gaze adjusted length (CGAL). Angle, direction, and vector strength of both 2D and 3D scans were calculated by an artificial intelligence algorithm and tested for agreement with hemispheric ischemia location. CGAL measurements were correlated to NIHSS scores. Follow up MRI data was used to evaluate the sensitivity and specificity of CGAL in the identification of AIS.The final analysis included 122 patients. A strong agreement was found between 3D gaze direction and hemispheric ischemia location. CGAL measurements were highly correlated with NIHSS score (r = .72, P = .01). A CGAL >0.25, >0.28, and >0.35 exhibited a sensitivity of 91%, 86%, and 82% and specificity of 66%, 89%, and 89%, respectively, in AIS identification. A CGAL >0.28 has the best sensitivity-specificity balance in the identification of AIS. A CGAL >0.25 has the highest sensitivity.Given CED''s correlation with NIHSS score a 1/4 deviation in the ipsilateral direction is a sensitive ancillary radiographic sign to assist radiologists in making a correct diagnosis even when not presented with full clinical data.  相似文献   
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