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PURPOSE: To compare measured visual field extent for a 6 degrees stimulus (typical size used in studies of infants) with a 1.5 degrees stimulus (similar to the largest size used in Goldmann perimetry) in young infants. METHODS: A total of 120 infants (60 each at 3.5 months and 7 months of age) and 24 adults were tested monocularly with a kinetic perimetry procedure using a black double-arc perimeter. Each subject was tested with either a 6 degrees or 1.5 degrees white sphere, which was mounted on a black wand and moved smoothly toward the intersection of the perimeter arms at 3.4 degrees /s. Visual field extent along each perimeter arm was defined as the median of 2 to 3 measurements of the position of the leading edge of the stimulus when the subject made an eye movement toward the stimulus. RESULTS: The 6 degrees stimulus produced larger measured visual field extent than the 1.5 degrees stimulus in 3.5-month olds (temporal field only) and in 7-month olds (nasal and temporal field), but not in adults. CONCLUSIONS: Using the testing conditions of the present study, increasing stimulus size beyond the largest used in a Goldmann perimeter (approximately 2 degrees) increases measured visual field extent in young infants, but not in adults. This may relate to differences in peripheral summation areas or to differences in attentional factors between infants and adults.  相似文献   
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Sickle cell disease (SCD) is a genetic disorder that is most prevalent among those of African American and Mediterranean descent. Hemoglobin SS is the most severe form of SCD and carries an increased risk for stroke. Although the initial treatment for stroke is an exchange transfusion, the use of routine, chronic transfusion therapy (CTT) has been shown to help prevent this neurological injury. The treatment plan is rigorous and time consuming, both of which impact one's quality of life (QoL). The purpose of this study was to explore QoL, from the child's perspective, as it is affected by CTT Semistructured interviews were performed on 10 children undergoing CIT: Five themes emerged from the data: (a) pain, (b) school issues, (c) disease knowledge, (d) transfusion therapy, and (e) having a stroke. Data from this study reveal that CTT does have an impact on QoL. This information is important to share with those making CTT treatment decisions.  相似文献   
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BACKGROUND: Our objective was to determine the cost-effectiveness of a comprehensive, risk-based triage system, composed of multiple critical pathways, with the use of early myocardial perfusion imaging (MPI) in low-risk patients. We found previously that a chest pain evaluation system that uses MPI in low-risk patients was safe and effective, but the cost-effectiveness of this approach was not studied. METHODS AND RESULTS: We compared two groups. The Acute Cardiac Team (ACT) group (n = 874) was assigned prospectively to 1 of 4 risk levels by emergency department (ED) physicians. Level 1, 2, and 3 patients were admitted; level 4 patients were evaluated in the ED. Level 3 and 4 patients underwent ED MPI. The control group (n = 713) represented consecutive patients evaluated in the prior year according to standard care and assigned retrospectively to an ACT level based on the presenting electrocardiographic and clinical data. Record and hospital administrative data were assessed for clinical variables, outcomes, lengths of stay, and all expenses incurred within 30 days of the index visit. The baseline characteristics of the two groups were similar, including age, sex, myocardial infarction prevalence, and 30-day revascularization rates within each level or between the two groups. Mean costs per encounter were reduced for the ACT patients for each level, which was significant when all patients were compared ($5,030 +/- $7,081 vs $6,044 +/- $10,432, P =.02). Use of MPI in the low-risk patients was associated with reduced costs (level 3, $4,958 +/- $4,948 vs $5,051 +/- $7,036; level 4, $1,529 +/- $2,664 vs $1,794 +/- $6,854) and was associated with a significantly lower angiography rate and shorter length of stay. CONCLUSIONS: Implementation of a comprehensive strategy for chest pain evaluation and triage reduced overall costs for patients with chest pain on presentation. Acute MPI in the ED setting did not increase net cost.  相似文献   
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On inpatient psychiatric units, nurses control the tone, pace, and activity level of the environment. But under the influence of factors such as high patient acuity and negative group contagion, a milieu can become unacceptably loud and chaotic. A volatile milieu is a potentially dangerous environment because patients' anxiety and agitation can quickly lead to acting out and aggression. This article focuses on how nurses can regain control of a milieu spiralling into chaos by tightening the structure of the routine, anticipating potential problems, and maintaining a confident calm manner. The charge nurse orchestrates the staff group's response to escalation through detailed planning, decisive interventions, and strategic use of every available resource.  相似文献   
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A cancer-specific self-reporting quality of life questionnaire has been validated. The questionnaire is designed to assess physical functioning, role functioning, cognitive functioning, emotional functioning, social functioning, pain, fatigue, emesis and quality of life by means of multi-item scales, and other disease- and treatment-related symptoms by means of single items. The questionnaire was completed by 126 head and neck cancer patients with a mean age of 67 years. The internal consistency (scale reliability) was satisfactory for all scales but one. Correlations between scales and items assessing the same underlying dimension were also satisfactory. The questionnaire discriminates between patient subgroups and between acute, subacute and late toxicity. Patient compliance was high. The questionnaire provided valuable information, and most of the scales/items functioned well. A few problems were found, especially with the modified visual analogue scales, and minor modifications will be made.  相似文献   
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The purpose of this study was to examine motor learning and retention given extensive practice in two fundamentally different movement sequences. One sequence was a memory-driven task (performing a series of whole body positions from memory) and the other a context-driven task (buttoning). Practice took place over 3 weeks, with performance measured weekly; retention was measured weekly for 3 weeks after practice. There were 7 people with Parkinson's disease (PD) and 7 age-matched neurologically healthy people who participated in this study. Both groups improved performance on both tasks with practice, with the majority of the change for the PD group occurring between 1 and 2 weeks of practice. Although those with PD did not necessarily perform as well as age-matched controls, they learned both sequences in a manner similar to age-matched controls, and exhibited retention across the 3-week retention interval. If people with PD are given sufficient practice they can learn and retain both memory-based and context-driven movement sequences as well as age-matched controls. The results provide support for maintaining physical activity and for intervention through movement therapy.  相似文献   
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Rats with lesions of the medial prefrontal, posterior parietal,or posterior temporal cortex were tested in five spatial navigationtasks, which varied in egocentric or allocentric demands, avisual discrimination task, and two delayed nonmatching-to-sampletasks. Rats with prefrontal lesions were impaired at every spatialnavigation task, whereas rats with posterior parietal lesionshad selective spatial navigation impairments. Rats with prefrontallesions were also impaired at a visual delayed nonmatching-to-sampletask, as they were unable to learn the task, even with no delay.The results are consistent with the idea that the basic planof mammalian cortex includes prefrontal, posterior parietal,and posterior temporal regions, each of which have generallysimilar functions across mammalian taxa. There are, however,species-typical differences that reflect specific ecologicalpressures on the development of the different regions.  相似文献   
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