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评价无支架异种生物瓣膜主动脉瓣替换术后2年左室功能的变化。将80例同期施行主动脉瓣替换病人分为2组,50例(年龄69.3±9.3岁)应用TorontoSPVTM瓣;30例(年龄71.6±7.7岁)作为对照组接受支架人工瓣膜替换。术前、术后1、6、12及24个月间记录M型及Doppler超声心动图,采用计算机图像数字分析,定量测定左室功能的变化。随访期间,Toronto组主动脉瓣跨瓣压差为0.8±0.6kPa(6.0±4.5mmHg),明显低于对照组2.3±0.9kPa(17.3±6.8mmHg);术后1个月,左室心肌质量下降25%,左室+Vcf及-Vcf明显增加(2.0±0.8/1.4±0.3s-1,P<0.01;2.8±1.2/1.8±0.7s-1,P<0.01)。术后6个月,左室功能进一步改善,心室肥厚的消退更趋完全,该变化在其后的随访期间保持稳定。结论:与支架瓣膜相比,无支架异种生物瓣膜具有较大瓣口开放面积及低跨瓣压差,这促进了术后左室功能的恢复及病理性肥厚的逆转 相似文献
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Richard S E Keefe Larry J Seidman Bruce K Christensen Robert M Hamer Tonmoy Sharma Margriet M Sitskoorn Stephanie L Rock Sandra Woolson Mauricio Tohen Gary D Tollefson Todd M Sanger Jeffrey A Lieberman 《Neuropsychopharmacology》2006,59(2):97-105
BACKGROUND: Neurocognitive deficits are severe in first-episode psychosis. METHODS: Patients (N = 263) with first-episode psychosis (schizophrenia, schizoaffective, or schizophreniform disorders) were randomly assigned to double-blind treatment with olanzapine (mean 11.30 mg/day) or haloperidol (mean 4.87 mg/day) for 104 weeks. A neurocognitive battery was administered at baseline (n = 246) and 12 (n = 167), 24 (n = 126), 52 (n = 89), and 104 (n = 46) weeks during treatment. Weighted principal component and unweighted composite scores were derived from individual tests. RESULTS: Both treatment groups demonstrated significant improvement on both composite scores. On the basis of the weighted composite score, olanzapine had greater improvement than haloperidol only at 12 (p = .014) and 24 (p = .029) weeks. For the unweighted composite, olanzapine had significantly better improvement compared with haloperidol only at week 12 (p = .044). At week 12 only, olanzapine improved performance on the Digit Symbol and Continuous Performance Test significantly more than haloperidol. CONCLUSIONS: Both antipsychotic agents appeared to improve neurocognitive functioning among first-episode psychosis patients with schizophrenia. A significantly greater benefit in terms of neurocognitive improvement was found with olanzapine than with haloperidol at weeks 12 and 24. 相似文献
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As part of its effort to assure a safe food supply, the Food and Drug Administration maintains a passive surveillance system for the reporting and followup of complaints related to food items. This surveillance system, called the Complaint Reporting System, records and investigates consumer complaints about the quality of a specific food item, its packaging, or unexpected effects following consumption of the food. This study, relying on data gathered from the 2,726 reports of discovery of a foreign object in a food item during fiscal year 1989, develops a profile of consumer complaints, focusing on those associated with resultant injury or illness. Fourteen percent of all reported cases of foreign object exposure cited resultant illness or injury. The most common foreign object reported in food is glass, and the most common injury is a laceration or abrasion of soft tissues of the perioral area, including the throat. There was a disproportionate representation of children younger than age 3 years with documented illness or injury. Only 3 percent of the complaints came from attending health professionals; 82 percent were self-reported. Practitioner awareness of the system is limited primarily because literature in this area is scant. The collection and investigation of reports of foreign objects in food are important because such reports provide early warnings of potential problems with manufacturers'' food items. Although data suggest that severe injury from foreign object ingestion is rare, continued monitoring is warranted. Health professionals are encouraged to report such injuries through the existing system. 相似文献