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The 5-year “Preventing Alcohol Trauma: A Community Trial” project in the United States was designed to reduce alcohol-involved injuries and death in three experimental communities. The project consisted of five mutually reinforcing components: (1) Community Mobilization Component to develop community organization and support, (2) Responsible Beverage Service Component to establish standards for servers and owner/managers of on-premise alcohol outlets to reduce their risk of having intoxicated and/or underage customers in bars and restaurants, (3) Drinking and Driving Component to increase local DWI enforcement efficiency and to increase the actual and perceived risk that drinking drivers would be detected, (4) Underage Drinking Component to reduce retail availability of alcohol to minors, and (5) Alcohol Access Component to use local zoning powers and other municipal controls of outlet number and density to reduce the availability of alcohol. This paper gives an overview of the rationale and causal model, the research design and outline of each intervention component for the entire prevention trial.  相似文献   
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Lesions in the distal portion of coronary arteries are technological challenges with currently available percutaneous transluminal coronary angioplasty (PTCA) equipment. A study was performed at multiple centers to determine if new "fixed-wire" devices with a modified distal tip (a 2-cm flexible tip and 1-cm standard tip) would be useful in these situations. Three hundred twenty-three patients were included in the study, 75% male, mean age 63 ± 11 years. Four hundred ninety-three lesions were attempted; the overall success rate was 85%. Forty-six (14.2%) clinical complications occurred including: 5 deaths (1.1%); 2 nonfatal myocardial infarctions (0.6%); and 6 emergency coronary artery bypass grafting procedures (2.6%). A device malfunction was noted in 32 patients (9.9%), and included: 8 balloon ruptures or perforations (2.0%); 6 bent or damaged tips (1.9%); and 4 shaft/manifold leaks (1.2%). Two-month follow-up assessment for restenosis was done in 352 of 371 (95%) patients and at that time 89% were asymptomatic, had a negative functional test, or patent PTCA site by angiography. The new fixed-wire PTCA catheters with 1- and 2-cm flexible tips hold promise for dilating lesions in distal locations with an acceptable rate of complications. Additional investigation is needed to determine their role in the treatment of coronary artery disease with PTCA.  相似文献   
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We have examined the effect of preoperative i.v. administrationof three different histamine type 2 (H2) antagonists (cimetidine400 mg, ranitidine 80 mg and famotidine 20 mg) or metoclopramide10 mg i.v. on the duration of neuromuscular block produced byan intubating dose (1 mg kg–1) of suxamethonium. The studywas conducted blindly in 70 post partum patients, weighing between45 and 120 kg, scheduled for tubal ligation. The duration ofneuromuscular block following suxamethonium was measured froma chart recording of train-of-four (TOF) electromyographic responses.The time from onset of 95% block to 25% recovery ("block time") was not significantly different between the groups receivingcimetidine (A), ranitidine (B), famotidine (C), and control(E). However, there was prolongation of neuromuscular blockin patients receiving suxamethonium and metoclopramide (D).  相似文献   
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The Effects of Magnetic Resonance Imaging on Implantable Pulse Generators   总被引:2,自引:0,他引:2  
The effects of magnetic resonance imaging were assessed on four dual chamber and two single chamber pulse generators. The tests were performed with a resistive, water-cooled magnet operating at 0.15 T. The 6.4-MHz radiofrequency (RF) field was operated at a maximum power of 1,000 watts with a period adjusted from 130 to 500 ms. Reed switch closure occurred in all six pulse generators tested when placed near the entrance of the magnetic resonance imaging scanner, and the generators reverted to asynchronous operation unless programmed to the "magnet off" mode. None of the pulse generators exhibited any alterations in programmed parameters or in the ability to be reprogrammed after RF pulsing. When the RF field was turned on, there was no change in the asynchronous paced cycle length in four pulse generators; however, during RF scanning there was rapid cardiac stimulation at the RF pulse period in one single chamber and one dual chamber pulse generator.  相似文献   
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