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Objective To determine the efficacy of minocycline and rifampin-impregnated catheters compared to non-impregnated catheters in critically ill patients.Design Prospective, randomized, double-blind, controlled, multicenter trial.Setting Intensive care units of seven acute-care teaching hospitals in Spain.Patients Intensive care unit patients requiring triple-lumen central venous catheter for more than 3 days.Interventions At catheter insertion, 228 patients were randomized to minocycline and rifampin-impregnated catheters and 237 to non-impregnated catheters. Skin, catheter tip, subcutaneous segment, hub cultures, peripheral blood and infusate cultures were performed at catheter withdrawal. The rate of colonization, catheter-related bloodstream infection (CRBSI) and catheter-related clinical infectious complications (purulence at the insertion site or CRBSI) were assessed.Measurements and main results In the intention-to-treat analysis (primary analysis), the episodes per 1000 catheter days of clinical infectious complications decreased from 8.6 to 5.7 (RR =0.67, 95% CI 0.31–1.44), CRBSI from 5.9 to 3.1 (RR =0.53, 95% CI 0.2–1.44) and tip colonization from 24 to 10.4 (RR =0.43, 95% CI 0.26–0.73). Antimicrobial-impregnated catheters were associated with a significant decrease of coagulase-negative staphylococci colonization (RR =0.24, 95% CI 0.13–0.45) and a significant increase of Candida spp. colonization (RR =5.84, 95% CI 1.31–26.1).Conclusions The use of antimicrobial-impregnated catheters was associated with a significantly lower rate of coagulase-negative staphylococci colonization and a significant increase in Candida spp. colonization, although a decrease in CRBSI, increase in 30-day survival or reduced length of stay was not observed.Electronic Supplementary Material Supplementary material is available in the online version of this article at http://dx.doi.org/10.1007/s00134-004-2378-2This study was supported by a grant from Cook Europe.  相似文献   
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Ductal carcinoma in situ (DCIS) now represents up to 20% of breast cancer cases, yet its behaviour is still poorly understood. Morphological classifications go some way to predicting prognosis, but more sophisticated approaches are required to better tailor therapy to the individual. A number of biological molecules have been identified that appear to relate to prognosis and, in model systems, promote progression to invasive disease. Some of these, such as COX-2, provide real therapeutic opportunities, whilst other marker combinations are showing promise in categorising women according to risk. Gene expression studies have led to an emerging molecular classification of invasive breast cancer, and it is now evident that at least some of these molecular subtypes can be identified at the pre-invasive stage. The difference in frequency of these subtypes between DCIS and invasive cancer may hold clues as to the biological mechanisms underpinning disease transition. It is increasingly clear that the host microenvironment can have a major impact on disease behaviour, and as well as acting as potential predictive factors, the altered microenvironment phenotype also offers novel therapeutic opportunities.  相似文献   
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