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991.
Stent supported angioplasty is being performed in an increasing number of patients and, with advances in device technology, more morphologically complex lesions are being treated. In such a setting, it is extremely important to deliver the device to the target lesion. We describe a new technique that allows successful stent delivery in complex right coronary anatomy using the Judkins right guiding catheter. Cathet Cardiovasc Intervent 2001;53:405-409.  相似文献   
992.
PURPOSE: Our study compares clinical and therapeutic courses (corticosteroid response, corticosteroid amount, complications) in people with giant cell arteritis before and over 75 years, during the first year of treatment. METHODS: A series of 164 patients was retrospectively analysed (mean age: 73.3 years) among the two subgroups: before 75 and over 75 years. Patient received (monitoring of reduction in the corticosteroid dosage) a 240 mg intravenous bolus of methylprednisolone followed by 0.5 or 0.7 mg/kg/d of prednisone, or 0.7 mg/kg/d of prednisone without the bolus. RESULTS: Corticosteroid response was identical for the two groups, before and over 75 (patients with corticoresistance: 15% vs 11.4%; NS) and giant cell arteritis-related complications were equivalent (n = 2 vs n = 2; NS). Corticosteroid load was slightly lower in the elderly group (cumulative dose of corticosteroids during the first year of treatment 5.2 g vs 5.8 g; P = 0.03). Patients with rheumatic side effects (collapses of vertebral bodies, mainly) were more frequent in the elderly group (15.5% vs 4.3%; P = 0.01), in spite of a limited mean follow-up period (10.7 months). CONCLUSION: Even if steroid response was identical in the therapeutic course of giant cell arteritis, rheumatic side effects appeared more frequent in the elderly group (over 75 years). In order to obtain a corticosteroid-sparing effect, new studies are necessary to evaluate a reduced initial dosage of corticosteroids.  相似文献   
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The THIN-B metallo-beta-lactamase, a subclass B3 enzyme produced by the environmental species Janthinobacterium lividum, was overproduced in Escherichia coli by means of a T7-based expression system. The enzyme was purified (>95%) by two ion-exchange chromatography steps and subjected to biochemical analysis. The native THIN-B enzyme is a monomeric protein of 31 kDa. It exhibits the highest catalytic efficiencies with carbapenem substrates and cephalosporins, except for cephaloridine, which acts as a poor inactivator. Individual rate constants for inactivation by chelators were measured, suggesting that inactivation occurred by a mechanism involving formation of a ternary complex.  相似文献   
997.
The role of the AcrAB-TolC pump in macrolide and ketolide susceptibility in Escherichia coli and Enterobacter aerogenes was studied. Efflux pump inhibitor restored erythromycin, clarithromycin, and telithromycin susceptibilities to multidrug-resistant isolates. No modification of telithromycin accumulation was detected in E. aerogenes acrAB or tolC derivatives compared to that in the parental strain. Two independent efflux pumps, inhibited by phenylalanine arginine beta-naphthylamide, expel macrolides and telithromycin in E. aerogenes.  相似文献   
998.
Malalignment, in particular femoral component malrotation, is a commonly accepted failure mode in total knee arthroplasty. The general objective of this paper is twofold: firstly, it accentuates clinical observations of the effects of rotational malalignment in total knee arthroplasty. Secondly, it discusses the relevant parameters of existing knee joint models with regards to rotational malalignment and its biomechanical background, thereby setting a basis for future studies. To summarise, when modelling malalignment in total knee arthroplasty, the following aspects should be considered: Friction between the implant components, ligamentous and capsular structures, deformable body to model the PE inlay, and an in vivo validation of the model. Because of the large variance in anthropometrical data between individuals, future knee joint models should also incorporate individual data.  相似文献   
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OBJECTIVES: Candidiasis can be associated with the formation of biofilms on bioprosthetic surfaces and the intrinsic resistance of Candida albicans biofilms to the most commonly used antifungal agents has been demonstrated. In this study, we report on the antifungal activity of caspofungin at two different concentrations, on C. albicans and Candida parapsilosis biofilms with different ages of maturation. METHODS: Fifteen strains of C. albicans (10 strains susceptible to fluconazole in vitro and five strains resistant to this antifungal agent) and six strains of C. parapsilosis (all were susceptible to fluconazole in vitro) were studied. The antifungal activity of caspofungin was assessed by looking for a significant inhibition of the metabolic activity of yeasts within biofilms. Biofilms of Candida were produced in vitro, on silicone catheters. RESULTS: Caspofungin used at MIC did not modify the metabolic activity of C. albicans, whatever the maturation age of the biofilms. The same concentration of caspofungin significantly reduced the metabolism (P相似文献   
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