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41.
Favorable early results with mechanical angioplasty devices and laser-assisted balloon angioplasty have resulted in aggressive marketing and a rapid increase in the use of these devices for the treatment of femoropopliteal occlusive disease. Recent reports, however, have questioned the durability of these less invasive procedures. Since 1986 we have been involved in the clinical investigation of the Kensey dynamic angioplasty instrument and laser-assisted balloon angioplasty. One hundred two balloon angioplasty procedures assisted by the Nd:YAG laser (n = 56) and the Kensey dynamic angioplasty instrument (n = 46) were performed for the treatment of femoropopliteal occlusive lesions. Both Kensey dynamic angioplasty instrument and laser-assisted balloon angioplasty groups were similar with regard to age, operative indication, preoperative ankle-brachial index, lesion length, and distal runoff. Mean follow-up was 19 months in the Kensey dynamic angioplasty instrument group and 15 months in the laser-assisted balloon angioplasty group. Technically successful recanalization was achieved in 67% of Kensey dynamic angioplasty instrument-assisted balloon angioplasty procedures and 82% of laser-assisted balloon angioplasty procedures. Early hemodynamic and clinical improvement was obtained in 59% of Kensey dynamic angioplasty instrument-assisted balloon angioplasty procedures and 57% of laser-assisted balloon angioplasty procedures. Two-year clinical success by life-table analysis was 37% in the Kensey dynamic angioplasty instrument group and 19% in the laser-assisted balloon angioplasty group. The level of subsequent surgical revascularization was not altered in any patient by Kensey dynamic angioplasty instrument-assisted balloon angioplasty or laser-assisted balloon angioplasty.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Despite a great proliferation of new media and technologies, the traditional live lecture is still highly regarded among scientists as an effective means of teaching and communication--and the 'lantern slide' remains the most popular lecturer's aid. Here are a few thoughts on how to create good slides and how to make the best use of them.  相似文献   
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Virus diversity and escape from immune responses are the biggest challenges to the development of an effective vaccine against HIV-1. We hypothesized that T-cell vaccines targeting the most conserved regions of the HIV-1 proteome, which are common to most variants and bear fitness costs when mutated, will generate effectors that efficiently recognize and kill virus-infected cells early enough after transmission to potentially impact on HIV-1 replication and will do so more efficiently than whole protein-based T-cell vaccines. Here, we describe the first-ever administration of conserved immunogen vaccines vectored using prime-boost regimens of DNA, simian adenovirus and modified vaccinia virus Ankara to uninfected UK volunteers. The vaccine induced high levels of effector T cells that recognized virus-infected autologous CD4+ cells and inhibited HIV-1 replication by up to 5.79 log10. The virus inhibition was mediated by both Gag- and Pol- specific effector CD8+ T cells targeting epitopes that are typically subdominant in natural infection. These results provide proof of concept for using a vaccine to target T cells at conserved epitopes, showing that these T cells can control HIV-1 replication in vitro.  相似文献   
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Sotalol was compared with amiodarone in this open randomizedmulticentre study of patients with ventricular tachycardia orfibrillation not associated with acute myocardial infarctionrefractory to or intolerant of Class I drugs. 16 of 30 patientstreated with amiodarone completed 12 months on therapy, fivewere withdrawn because of recurrent ventricular tachycardiaand nine because of presumed adverse drug reactions, complianceproblems or protocol violation. Four of those who were withdrawndied within 12 months. Sixteen of 29 patients completed 12 months on sotalol, one waswithdrawn because of ventricular tachycardia and nine becauseof presumed adverse drug reactions, poor compliance or the needfor coronary artery surgery. Three died on treatment and twoafter withdrawal but within 12 months of entering the study. When the results are analysed by intention to treat there wasno significant difference in antiarrhythmic efficacy or in theincidence of side-effects severe enough to warrant withdrawalfrom the trial. There was an increase in left ventricular ejectionfraction in those treated with sotalol, which, because of itspharmacokine-tics, is an attractive alternative to amiodaronefor patients with malignant ventricular arrhythmias who cantolerate ß-adrenergic blockade.  相似文献   
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The autoimmune nature of chronic immune thrombocytopenic purpura (ITP) in adults is widely accepted. In contrast, the pathogenetic mechanism in acute and chronic ITP in children is not known. In this report, we studied 39 children with destructive thrombocytopenia, 15 patients with acute ITP and 24 patients with chronic ITP. Platelet autoantibodies to platelet glycoprotein IIb/IIIa were detected in 14 of 24 patients (58.3%) in the chronic ITP group and in four of 15 (26.7%) with acute ITP. Binding ratios (+/- SD) of positive patients were significantly greater (P = .01) in chronic ITP (8.0 +/- 9.1) when compared with those of acute ITP where the binding ratios were only slightly above the normal range (1.9 +/- 0.4). The results show that autoantibodies against platelet glycoproteins are present in the majority of children with chronic ITP confirming the autoimmune nature of this disorder. The minimal elevation seen in the positive children with acute ITP suggests a different pathogenetic mechanism. These data suggest that this approach may be useful in differentiating acute from chronic ITP patients.  相似文献   
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