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1.

Background

Physicians treating nonvalvular atrial fibrillation (AF) assess stroke and bleeding risks when deciding on anticoagulation. The agreement between empirical and physician-estimated risks is unclear. Furthermore, the association between patient and physician sex and anticoagulation decision-making is uncertain.

Methods

We pooled data from 2 national primary care physician chart audit databases of patients with AF (Facilitating Review and Education to Optimize Stroke Prevention in Atrial Fibrillation and Coordinated National Network to Engage Physicians in the Care and Treatment of Patients with Atrial Fibrillation Chart Audit) with a combined 1035 physicians (133 female, 902 male) and 10,927 patients (4567 female and 6360 male).

Results

Male physicians underestimated stroke risk in female patients and overestimated risk in male patients. Female physicians estimated stroke risk well in female patients but underestimated the risk in male patients. Risk of bleeding was underestimated in all. Despite differences in risk assessment by physician and patient sex, > 90% of patients received anticoagulation across all subgroups. There was modest agreement between physician estimated and calculated (ie, CHADS2 score) stroke risk: Kappa scores were 0.41 (0.35-0.47) for female physicians and 0.34 (0.32-0.36) for male physicians.

Conclusions

Our study is the first to examine the association between patient and physician sex influences and stroke and bleeding risk estimation in AF. Although there were differences in agreement between physician estimated stroke risk and calculated CHADS2 scores, these differences were small and unlikely to affect clinical practice; further, despite any perceived differences in the accuracy of risk assessment by sex, most patients received anticoagulation.  相似文献   
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Aim There is a controversy as to whether dyslexic children present visuo-motor disabilities such as vergence and accommodative problems assessed with orthoptic tests. The purpose of this study is to re-examine this issue in a large population of children. Methods Extensive orthoptic evaluation was made in 57 dyslexic and 46 non-dyslexic (“normal”) age-matched children. Convergence and divergence capacities were evaluated at two distances (30 cm and 400 cm). Results Binocular vision measured with stereo-acuity tests was normal in dyslexics. In contrast, the near point of convergence was significantly more remote in dyslexics; most importantly, divergence at both far and near distance was significantly more reduced in dyslexics (median value 4 pD and 10 pD, respectively, at far and near) than in “normals” (median value 6 pD and 12 pD, at far and near). Conclusion The existence of the divergence deficit at far distance indicates the presence of deficit of divergence per se, independently from convergence and accommodation relaxation. This result is novel and corroborated by physiological studies indicating distinct control of convergence and divergence, both at the cortical and subcortical premotor level. We conclude that vergence deficits are frequently present in dyslexics, and that dyslexics should be re-educated; training should address distinctively convergence and divergence subsystems.  相似文献   
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The saccadic system has been traditionally regarded as two-dimensional (horizontal, vertical) and basically conjugate in the two eyes. However, saccades to disparate targets (e.g., targets in real three-dimensional space that are located in different directions and at different distances) are naturally disconjugate. We report here that memory-guided saccades to a disparate target flashed 1 s earlier become disconjugate following repeated trials. After 15 min of repetition, the disconjugacy persists even when the target to be remembered is no longer disparate. This suggests fast memory-based learning. Learning, however, fails to occur if, during the repetition trials, the memory delay is 2 s. These findings suggest that the saccadic system has access to a 3D representation of targets and is gifted with 3D short-term memory and learning capacity. Received: 7 July 1997 / Accepted: 25 May 1998  相似文献   
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We tested the ability of normal subjects to make changes in the conjugacy of their saccades. Subjects dichoptically viewed a grid the size of which was 10% larger in one eye. The grids were centred onto a flat screen at 57 cm or 1 m from the subject. Horizontal saccades immediately became larger in the eye viewing the larger grid. For some subjects this disconjugacy persisted even under subsequent monocular viewing. Such persistent changes occurred mainly in the field where the required disconjugacy was divergent for centrifugal saccades, convergent for centripetal saccades. Vertical saccades also developed compensatory disconjugacy; its amplitude was smaller but less variable. To explain these results we propose a fast associative learning mechanism that pairs peripheral disparity with saccades and is capable of producing saccade disconjugacy even in the absence of disparity. For horizontal saccades a secondary conditioning of monocular depth cues by the disparity would also be involved.  相似文献   
8.
BK virus nephropathy (BKVN) is now recognized as a major cause of renal allograft loss. Recent reports suggest that retransplantation in patients with graft loss due to BKVN is safe after return to dialysis. Since early transplantation is associated with improved outcomes, it would be advantageous if this procedure could be performed prior to ultimate graft loss. However, little data are available regarding the safety of this approach during active viremia. In this report, we describe successful preemptive retransplantation with simultaneous allograft nephrectomy in two patients with active BKVN and viremia at the time of surgery. With 21- and 12-month follow-up, respectively, both patients have stable allograft function and no evidence for active viral replication. We conclude that preemptive retransplantation can be considered in patients with failing allografts due to BKVN.  相似文献   
9.
BACKGROUND: There is concern that shrimp-allergic individuals may react to glucosamine-containing products as shrimp shells are a major source of glucosamine used for human consumption. OBJECTIVE: The purpose of this study was to determine whether shrimp-allergic individuals can tolerate therapeutic doses of glucosamine. METHODS: Subjects with a history of shrimp allergy were recruited and tested for both shrimp reactivity via a prick skin test and shrimp-specific IgE by an ImmunoCAP assay. Fifteen subjects with positive skin tests to shrimp and an ImmunoCAP class level of two or greater were selected for a double-blind placebo-controlled food challenge (DBPCFC) using glucosamine-chondroitin tablets containing 1,500 mg of synthetically produced (control) or shrimp-derived glucosamine. Immediate reactions, including changes in peak flow and blood pressure, and delayed reactions (up to 24 h post-challenge) via questionnaire were noted and assessed. RESULTS: All subjects tolerated 1,500 mg of both shrimp-derived or synthetic glucosamine without incident of an immediate hypersensitivity response. Peak flows and blood pressures remained constant, and no subject had symptoms of a delayed reaction 24 h later. CONCLUSION: This study demonstrates that glucosamine supplements from specific manufacturers do not contain clinically relevant levels of shrimp allergen and therefore appear to pose no threat to shrimp-allergic individuals.  相似文献   
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Summary An epidemiological survey of hereditary ataxias and paraplegias was conducted in Molise, a region of Italy (335, 211 inhabitants on 1 January 1989). Total prevalence was 7.5 x 10–5 inhabitants (95% confidence limits 4.8–11.1). There were 7 patients with Friedreich's disease, 5 with early onset cerebellar ataxia with retained tendon reflexes, 4 with ataxia-telangiectasia, 9 with hereditary spastic paraplegias (2 autosomal dominant and 7 autosomal recessive cases). There was no patient with autosomal dominant cerebellar ataxia.  相似文献   
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