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41.
BACKGROUND: Delays in seeking treatment for signs and symptoms of acute myocardial infarction are longer for African Americans than for whites. OBJECTIVE: To determine factors associated with prolonged delay and the extent to which perceived racism influences prehospital delay in African Americans with acute myocardial infarction. METHODS: Sixty-one African Americans with acute myocardial infarction were interviewed within 1 month of hospital admission. Delay times were calculated on the basis of the interviews. Independent t tests and chi(2) tests were used to determine factors associated with prolonged delays. RESULTS: Median delay was 4.25 hours and did not differ significantly between women and men (4.42 vs 3.50 hours). Most patients (69%) experienced their initial signs and symptoms at home, often witnessed by family members or friends (70%). Delay was longer for insured patients than for uninsured patients (4.45 vs 0.50 hours). Single, widowed, or divorced patients had longer delay times than did married patients (5.33 vs 2.50 hours), and patients with diabetes delayed longer than did those without diabetes (7.29 vs 3.50 hours). Perceived racism did not differ significantly between patients who delayed seeking treatment and those who did not. CONCLUSIONS: Median delay times were substantially longer than the recommended time of less than 1 hour, reducing the benefit from reperfusion therapies. Education and counseling of patients and their families should be a major strategy in optimizing patients' outcomes and decreasing the time to definitive treatment.  相似文献   
42.
The practicality of using second-order fixed-interval schedules in studies of heroin reinforcement with rats was examined. Optimum rates of responding were obtained with a dose of 0.03 mg/kg/infusion and an interval duration of 3 min. In addition, schedules consisting of a only a single interval were shown to be practical, leading to response rates comparable to those obtained with cocaine or food as reinforcer.The views expressed in this publication are those of the author and do not necessarily represent those of the Addiction Research Foundation  相似文献   
43.
Public health law has been one of the leading contributors to the extension of life expectancy in the 20th century. Nonetheless, the legal infrastructure supporting public health law in the United States is underdeveloped and nonuniform. With national interest growing in public health agency accreditation, the individual legal approach taken by states may pose an obstacle to wholesale adoption of a proposed voluntary national model. This article describes the legal foundations supporting accreditation or assessment programs in states participating in the Multi-State Learning Collaborative, a project funded by the Robert Wood Johnson Foundation. The Turning Point Model State Public Health Act is recommended as one option to resolve the current impasse, assist in acceptance of a national accreditation model, and provide a common public health legal infrastructure.  相似文献   
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(18)F-Fluoride PET allows noninvasive evaluation of regional bone metabolism and has the potential to become a useful tool for assessing patients with metabolic bone disease and evaluating novel drugs being developed for these diseases. The main PET parameter of interest, termed K(i), reflects regional bone metabolism. The aim of this study was to compare the long-term precision of (18)F-fluoride PET with that of biochemical markers of bone turnover assessed over 6 mo. METHODS: Sixteen postmenopausal women with osteoporosis or significant osteopenia and a mean age of 64 y underwent (18)F-fluoride PET of the lumbar spine and measurements of biochemical markers of bone formation (bone-specific alkaline phosphatase and osteocalcin) and bone resorption (urinary deoxypyridinoline) at baseline and 6 mo later. Four different methods for analyzing the (18)F-fluoride PET data were compared: a 4k 3-compartmental model using nonlinear regression analysis (K(i-4k)), a 3k 3-compartmental model using nonlinear regression analysis (K(i-3k)), Patlak analysis (K(i-PAT)), and standardized uptake values. RESULTS: With the exception of a small but significant decrease in K(i-3k) at 6 mo, there were no significant differences between the baseline and 6-mo values for the PET parameters or biochemical markers. The long-term precision, expressed as the coefficient of variation (with 95% confidence interval in parentheses), was 12.2% (9%-19%), 13.8% (10%-22%), 14.4% (11%-22%), and 26.6% (19%-40%) for K(i-3k), K(i-PAT), mean standardized uptake value, and K(i-4k), respectively. For comparison, the precision of the biochemical markers was 10% (7%-15%), 18% (13%-27%), and 14% (10%-21%) for bone-specific alkaline phosphatase, osteocalcin, and urinary deoxypyridinoline, respectively. Intraclass correlation between the baseline and 6-mo values ranged from 0.44 for K(i-4k) to 0.85 for K(i-3k). No significant correlation was found between the repeated mean standardized uptake value measurements. CONCLUSION: The precision and intraclass correlation observed for K(i-3k) and K(i-PAT) was equivalent to that observed for biochemical markers. This study provided initial data on the long-term precision of (18)F-fluoride PET measured at the lumbar spine, which will aid in the accurate interpretation of changes in regional bone metabolism in response to treatment.  相似文献   
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47.
Four hundred twenty-eight white children (200 boys and 228 girls) ages 4.5-6.5 yr had spine, hip, and whole-body bone mineral density (BMD) and bone mineral content (BMC) measured by dual-energy X-ray absorptiometry(DXA) as part of the Iowa Bone Development Study. Anthropometric measurements, including height, weight, and body mass index (BMI) were determined for each child at the time the bone measurements were made. The age- and gender-specific height percentile based on the 2000 CDC Growth Charts (www.cdc.gov/growthcharts/) was determined for each child. These percentiles were used to classify children into four groups as defined by the 25th, 50th,and 75th percentile cutpoints. Percentile distributions were determined within each height quartile group to delineate percentiles (5th, 25th, 50th, 75th, 95th) for BMD and BMC. Gender differences in BMD and BMC were investigated before and after stratification into height groups. Boys had higher age-height-weight-adjusted means for most BMD and BMC measures except spine BMD. Bone measurements increased with height quartile, indicating that taller children have greater BMD and BMC compared to shorter children of the same age and gender. Within any given quartile,mean BMD and BMC measurements were similar for boys and girls, with the exception of hip BMD, for which values were consistently higher for boys (p < 0.05). In addition, whole-body BMC values were higher for boys in quartiles 1 and 3 (p < 0.05). These bone measures provide norms for young white children and serve as a reference for comparison with other racial and ethnic groups, as well as with childhood populations that are at risk for osteopenia because of chronic disease. Gender, age, and height are useful clinical predictors of BMD and BMC in young children.  相似文献   
48.
OBJECTIVE: The purpose of this study was to investigate the effects of therapy balls as seating on in-seat behavior and legible word productivity of students with attention deficit hyperactivity disorder (ADHD). Additionally, social validity was assessed to evaluate teacher and student opinions regarding the intervention. METHOD: A single subject, A-B-A-B interrupted time series design was employed across 3 students (2 males, 1 female) with ADHD. The study was conducted in a 4th grade inclusive classroom during daily language arts. During phases 1 and 3, the 3 participants and all other class members sat on chairs (in-seat on chair); during phases 2 and 4, everyone sat on therapy balls (in-seat on ball). Dependent variables were in-seat behavior and legible word productivity. Data were graphed and visually analyzed for differences between phases. RESULTS: Results demonstrated increases in in-seat behavior and legible word productivity for the students with ADHD when seated on therapy balls. Social validity findings indicated that generally the teacher and students preferred therapy balls. CONCLUSION: This study provides evidence that use of therapy balls for students with ADHD may facilitate in-seat behavior and legible word productivity.  相似文献   
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50.
BACKGROUND: It is common for older patients to present to accident and emergency (AE) departments after a fall. Management should include assessment and treatment of the injuries and assessment and correction of underlying risk factors in order to prevent recurrent falls. OBJECTIVES: To determine management of older patients presenting after a fall to the AE department of Groote Schuur Hospital in Cape Town, South Africa. METHOD: Hospital records were reviewed for a random sample of 100 patients aged 65 years and older presenting to the AE department after a fall, between December 2001 and May 2002. RESULTS: The mean age of the sample was 78.6 years (range 65-98 years); 72% of subjects were female. History of a previous fall, and history of drug or alcohol intake, were recorded in less than 20% of cases. Blood pressure and pulse rate were recorded in approximately 90% of cases, and pulse rhythm and postural blood pressure in 2%. Examination of the musculoskeletal system was done in 86% of cases and that of other systems in less than 50%; cognitive assessment was conducted in less than 30%. Radiological investigations were performed in 89% of cases, glucose and haemoglobin in 32%, renal profile and electrocardiogram in 5%, and urinalysis in 4%. Three-quarters of the patients were referred for further management: 52% to orthopaedic surgery, 12% to other surgical subspecialties, 6% to the general medical department, and 6% to other hospitals and clinics. No referrals were made to geriatric medicine, physiotherapy or occupational therapy. CONCLUSIONS: In managing elderly patients after a fall, the AE department focused on injuries sustained. Little effort was made to establish and manage risk factors, hence to prevent recurrent falls. Guidelines are needed for the management of such patients in AE departments.  相似文献   
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