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Background: It has recently been reported that reusable dispensers for surface disinfection tissues may be contaminated, especially with adapted Achromobacter species 3, when products based on surface-active ingredients are used. Fresh solution may quickly become recontaminated if dispensers are not processed adequately. Methods: We evaluated the abilities of six manual and three automatic processes for processing contaminated dispensers to prevent recolonisation of a freshly-prepared disinfectant solution (Mikrobac forte 0.5%). Dispensers were left at room temperature for 28 days. Samples of the disinfectant solution were taken every 7 days and assessed quantitatively for bacterial contamination. Results: All automatic procedures prevented recolonisation of the disinfectant solution when a temperature of 60–70°C was ensured for at least 5 min, with or without the addition of chemical cleaning agents. Manual procedures prevented recontamination of the disinfectant solution when rinsing with hot water or a thorough cleaning step was performed before treating all surfaces with an alcohol-based disinfectant or an oxygen-releaser. Other cleaning and disinfection procedures, including the use of an alcohol-based disinfectant, did not prevent recolonisation.Conclusions: These results indicate that not all processes are effective for processing reusable dispensers for surface-disinfectant tissues, and that a high temperature during the cleaning step or use of a biofilm-active cleaning agent are essential.  相似文献   
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Nitric oxide (NO) is a powerful vasodilator, involved in both physiological functions and pathophysiological alterations of various regulatory processes, for example, the maintenance of vascular tone and inflammation. The recently demonstrated impact of exogenous NO on the central nervous system extends its role under normal and pathological conditions. At times neuroprotective, at times neurotoxic, NO is capable of different effects depending upon the extent of cerebral damage, the cellular redox state, and the spatiotemporal coordinates and concentration at which it is synthesized. This review provides new insights into the short‐ and long‐term effects of endogenous and exogenous NO in brain injury. ANN NEUROL 2013;73:442–448  相似文献   
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BACKGROUND: In rodents, the development of alcoholic liver disease (ALD) after chronic alcohol feeding was shown to depend on the activity of enzymes that are necessary for production of reactive oxygen species (ROS) in phagocytes. The aim of this study was to determine the formation of ROS by resting and challenged phagocytes of patients with different stages of ALD in the presence of ethanol concentrations commonly found in the blood of alcohol abusers. PATIENTS AND METHODS: The release of ROS and the phagocytosis of bacteria by neutrophils and monocytes obtained from 60 patients, who were categorized in three groups due to the severity of ALD, were compared to that of 28 healthy controls. ROS release by these phagocytes was measured after challenging with endotoxin and the addition of ethanol (22 and 44 mM). RESULTS: Resting neutrophils but not monocytes from patients with severe stages of ALD produced significantly more ROS than those of healthy controls. Basal values of ROS production from neutrophils correlated closely to markers of the severity of ALD. ROS formation was depressed dose-dependently by ethanol in the healthy controls but not in alcohol abusers. CONCLUSIONS: Changes in the ROS metabolism of phagocytes found in this study might contribute to both the development of ALD and the impaired immune response occurring in patients with severe ALD.  相似文献   
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