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Objectives: To determine whether the Mac‐technique test can detect kinking of the chest tube upon thoracostomy tube placement. Methods: This was a prospective observational study that was conducted October 2000 through October 2001 in an urban Level 1 trauma center. There were 103 consecutive nonrandomized adult trauma patients who required immediate tube thoracostomy during their initial resuscitation who were entered into the study. The Mac‐technique test was performed during standard tube thoracostomy insertion to the appropriate depth. The test involved grasping the external portion of the thoracostomy tube, turning it clockwise 180°, and then releasing the tube. If the tube spontaneously spun back to its original position, the test was considered positive, and the tube was considered kinked. If the tube did not spontaneously spin back and stayed in position upon release, the test was considered negative. Regardless of the results of this test, the tube was secured, and a postprocedure chest radiograph was obtained. The criterion standard for determining a kinked chest tube was its appearance on this chest radiograph. Results: A total of 103 chest tubes were placed by using the Mac‐technique test. The test was positive in eight placements; four tubes were kinked on chest radiograph. The Mac‐technique test was negative in 95 placements; four tubes were kinked on chest radiograph. The Mac technique had a sensitivity of 50% (95% confidence interval [CI] = 15.7% to 84.3%), a specificity of 95.8% (95% CI = 89.6% to 98.8%), a positive likelihood ratio of 11.9, a negative likelihood ratio of 0.52, and an odds ratio using Yates correction of 20.3 (95% CI = 4.1 to 102.1). Conclusions: On the basis of this study, a positive Mac‐technique test is useful to detect chest tubes that are likely to be kinked after insertion and before securing.  相似文献   
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Nicotinic acid effectively treats each of the common lipid abnormalities found in the metabolic syndrome, and much progress has recently been made in understanding its mechanisms of action.Early concern that nicotinic acid can precipitate or worsen diabetes has been eased with recent trials, which demonstrated its safety and effectiveness in insulin-resistant states. Furthermore, nicotinic acid prevents cardiovascular disease and death in persons with a high prevalence of risk factors for the metabolic syndrome. When used by an experienced physician and taken by a motivated patient, nicotinic acid can be safe and effective in treating the dyslipidemia of the metabolic syndrome.  相似文献   
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Quantitation in gated perfusion SPECT imaging: The Cedars-Sinai approach   总被引:1,自引:0,他引:1  
Cedars-Sinai’s approach to the automation of gated perfusion single photon emission computed tomography (SPECT) imaging is based on the identification of key procedural steps (processing, quantitation, reporting), each of which is then implemented, in completely automated fashion, by use of mathematic algorithms and logical rules combined into expert systems. Our current suite of software applications has been designed to be platform- and operating system-independent, and every algorithm is based on the same 3-dimensional sampling scheme for the myocardium. The widespread acceptance of quantitative software by the nuclear cardiology community (QGS alone is used at over 20,000 locations) has provided the opportunity for extensive validation of quantitative measurements of myocardial perfusion and function, in our opinion, helping to make nuclear cardiology the most accurate and reproducible modality available for the assessment of the human heart.  相似文献   
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Integrated surveillance of infectious multi-source diseases using a combination of epidemiology, ecology, genetics and evolution can provide a valuable risk-based approach for the control of important human pathogens. This includes a better understanding of transmission routes and the impact of human activities on the emergence of zoonoses. Until recently New Zealand had extraordinarily high and increasing rates of notified human campylobacteriosis, and our limited understanding of the source of these infections was hindering efforts to control this disease. Genetic and epidemiological modeling of a 3-year dataset comprising multilocus sequence typed isolates from human clinical cases, coupled with concurrent data on food and environmental sources, enabled us to estimate the relative importance of different sources of human disease. Our studies provided evidence that poultry was the leading cause of human campylobacteriosis in New Zealand, causing an estimated 58–76% of cases with widely varying contributions by individual poultry suppliers. These findings influenced national policy and, after the implementation of poultry industry-specific interventions, a dramatic decline in human notified cases was observed in 2008. The comparative-modeling and molecular sentinel surveillance approach proposed in this study provides new opportunities for the management of zoonotic diseases.  相似文献   
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Ohne Zusammenfassung  相似文献   
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BACKGROUND: A hypertensive response to exercise (HRE) is associated with false-positive stress echocardiograms and myocardial perfusion single photon emission computed tomography (myocardial perfusion imaging [MPI]) defects even in the absence of coronary artery disease (CAD). Transient ischemic dilation (TID) of the left ventricle on stress MPI is a marker of severe CAD and future cardiac events. This study evaluated the association between an HRE and TID. METHODS AND RESULTS: Blinded quantitative TID assessment was performed in 125 patients who had an HRE and a summed stress score (SSS) of less than 4, as well as 125 control patients with an SSS of less than 4 and without an HRE matched for age, gender, and resting systolic blood pressure. Cardiac comorbidities, pretest Framingham risk, and exercise results were recorded. TID was defined as a stress-to-rest volume ratio of 1.22 or greater. An HRE was associated with a high prevalence of TID and significantly more TID than no HRE (25.6% vs 11.2%; odds ratio, 3.00 [95% confidence interval, 1.41-6.38]). TID was more prevalent even in subgroups with a low pretest probability CAD, including those without diabetes mellitus or angina. On conditional logistic regression analysis, an HRE was found to be independently associated with TID after consideration of other clinical and exercise MPI variables (odds ratio, 2.72 [95% confidence interval, 1.01-7.31]). CONCLUSION: An HRE is associated with a high prevalence of TID in patients without other significant perfusion defects, possibly as a result of global subendocardial ischemia induced by the HRE.  相似文献   
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