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101.
Epiploic appendagitis and omental infarction: pitfalls and look-alikes   总被引:3,自引:0,他引:3  
Epiploic appendagitis and omental infarction are benign self-limiting conditions that are more frequent than generally assumed. Both disorders frequently mimic symptoms of an abdominal surgical emergency, often leading to clinical misdiagnosis of appendicitis or diverticulitis. Because a misdiagnosis can result in an unnecessary laparotomy, a correct diagnosis is of great importance. Ultrasound and computed tomography can be used to make a reliable diagnosis. This pictorial essay illustrates the various ultrasonographic and computed tomographic appearances of epiploic appendagitis and omental infarction and focuses on their radiologic differential diagnoses and pitfalls. Received: 22 February 2001/Accepted: 18 April 2001  相似文献   
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Background: Although managed care organizations (MCOs) may be optimal settings for implementing tobacco use cessation clinical guidelines, such guidelines remain poorly implemented in many MCO settings.Purpose: We examined issues related to the implementation of guidelines in MCOs, to provide examples of studies that have addressed issues related to guideline implementation and to suggest ways behavioral medicine researchers can play a role in examining issues of how guidelines can be better implemented.Methods: Surveys of clinical guideline implementation, studies from the Robert Wood Johnson Foundation addressing tobacco use cessation in a managed care database, selected to illustrate issues related to system-wide implementation.Results: Surveys show that effective tobacco use cessation interventions remain underutilized in MCOs. A few studies have evaluated and shown the benefit of insurance coverage for tobacco use and dependence treatments, clinician reimbursement and leadership incentives, practice feedback, and leveraging administrative data to create tobacco use tracking systems. The studies also point to the need for large-scale, multidisciplinary, methodologically rigorous studies that allow one to isolate the effects of promising strategies as well as to explore synergistic effects as different system changes are combined.Conclusions: Tobacco use cessation guidelines need to be better implemented in MCOs. Behavioral medicine research needs to move beyond treatment efficacy and effectiveness studies to focus on rigorous evaluations of these and other strategies to enhance guideline implementation and dissemination. This research was supported by grants from the Tobacco-Related Disease Research Program (Taylor) and from the Robert Wood Johnson Foundation (Taylor and Curry).  相似文献   
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Ohne Zusammenfassung  相似文献   
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During the past few decades, management of patients with myocardial infarction has dramatically evolved. High-risk patients are now identified by a variety of noninvasive tests, and aggressive use of reperfusion strategies has improved clinical outcomes. Despite the benefits of reperfusion, only a few patients are eligible to receive thrombolytic therapy. Mortality rates among patients excluded from thrombolytic trials (15% to 20%) have been far greater than those eligible for treatment (3% to 10%). Because most deaths occur within the first few days of infarction, interventions designed to reduce mortality should be performed acutely. Immediate catheterization allows identification of high-risk anatomy that may benefit from surgery and allows coronary angioplasty to be performed as a reperfusion strategy (when appropriate). Furthermore, catheterization allows documentation of ejection fraction, vessel patency, number of diseased vessels, and residual stenosis, all of which have been predictive of prognosis. Conversely, frequently repeated noninvasive diagnostic tests are associated with increased cost, are generally performed in low-risk patients, and 60% to 80% of patients with myocardial infarction ultimately require catheterization anyway. It is possible that early catheterization and percutaneous transluminal coronary angioplasty when indicated may effectively risk stratify patients (eliminating the need for noninvasive testing), may reduce morbidity and mortality, and shorten the length of hospital stay.  相似文献   
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The present study was designed to investigate the presynaptic alpha 2-adrenoceptor function to inhibit norepinephrine (NE) release in blood vessels of reduced renal mass salt hypertensive rats (Na-loaded HT). Isolated perfused mesenteric vasculatures were prepared from Na-loaded HT and normotensive control rats (NT-control), and the NE release and vascular responsiveness were examined. Periarterial nerve stimulation caused a significantly greater release of NE and pressor responses in Na-loaded HT than in NT-control. Yohimbine, a potent alpha 2-adrenoceptor antagonist, demonstrated the facilitatory effects on NE release during nerve stimulation. The effects were significantly attenuated in Na-loaded HT compared with NT-control. These results demonstrate that vascular sympathetic nervous activity might be enhanced in Na-loaded HT. Furthermore, the increased NE release from vascular adrenergic neurons in Na-loaded HT could partially depend on impaired presynaptic alpha 2-adrenoceptor-mediated modulation, which might contribute to the pathogenesis and maintenance of this form of salt-dependent hypertension.  相似文献   
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