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Reliable discrimination between sinus tachycardia (ST) and pathologic tachycardia has been a major problem for automatic implantable antitachycardia devices. In patients whose sinus response to activity is as rapid or faster than their pathologic tachycardia (rate crossover), these unsophisticated devices deliver the programmed tachycardia response to either the pathologic or sinus tachycardia. Over a one-year period, 50 Intermedics Intertach Model 262–12 antitachycardia pulse generators were implanted to evaluate the specificity of a new group of tachycardia recognition algorithms. Patients were subjected to exercise testing and noninvasive programmed stimulation to demonstrate the efficacy of this new approach. The five recognition algorithms tested were various combinations of the following criteria: high rate HR), sudden onset (SO), rate stability (RS), and sustained high rate (SHR). False positive rates (tachycardia response inappropriately triggered by ST) were as follows: HR (93%); HR + SO (3%); HR + RS (63%); HR + (RS or SHR) (87%); HR + HS + SO (8%). Pair-wise significance testing between HR only and HR + SO (p < 0.001), HR + RS (p = 0.01) and HR + SO + RS (p < 0.001), demonstrated a significant reduction in the rate of false positives through the use of the sudden onset and rate stability criteria in concert with the standard high rate criterion. 相似文献
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Bulimia is a distinct diagnostic eating disorder with its most noted manifestation being the rapid ingestion of large quantities of food followed by its elimination through the mouth. Because of the dental implications of highly acidic stomach contents chronically being regurgitated, the dentist is in a unique position to help identify the patient with bulimia. Dental erosion is not only the most easily noted but also the most destructive of the many oral problems caused by bulimia. This report of case describes a preventive dental prosthesis that can be used by the patient with bulimia to protect those teeth that are most affected by dental erosion. The construction of the prosthesis is easily completed with materials in the dental office and provides a great service to the patient with bulimia. 相似文献
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TODD F. HEATHERTON LYNN T. KOZLOWSKI RICHARD C. FRECKER KARL-OLOV FAGERSTROM 《Addiction (Abingdon, England)》1991,86(9):1119-1127
We examine and refine the Fagerström Tolerance Questionnaire (FTQ; Fagerström, 1978). The relation between each FTQ item and biochemical measures of heaviness of smoking was examined in 254 smokers. We found that the nicotine rating item and the inhalation item were unrelated to any of our biochemical measures and these two items were primary contributors to psychometric deficiencies in the FTQ. We also found that a revised scoring of time to the first cigarette of the day (TTF) and number of cigarettes smoked per day (CPD) improved the scale. We present a revision of the FTQ: the Fagerström Test for Nicotine Dependence (FTND). 相似文献
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