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Background  

The archaeal exosome is formed by a hexameric RNase PH ring and three RNA binding subunits and has been shown to bind and degrade RNA in vitro. Despite extensive studies on the eukaryotic exosome and on the proteins interacting with this complex, little information is yet available on the identification and function of archaeal exosome regulatory factors.  相似文献   
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We hypothesize that the energy strategy of a cell is a key factor for determining how, or if, the immune system interacts with that cell. Cells have a limited number of metabolic states, in part, depending on the type of fuels the cell consumes. Cellular fuels include glucose (carbohydrates), lipids (fats), and proteins. We propose that the cell's ability to switch to, and efficiently use, fat for fuel confers immune privilege. Additionally, because uncoupling proteins are involved in the fat burning process and reportedly in protection from free radicals, we hypothesize that uncoupling proteins play an important role in immune privilege. Thus, changes in metabolism (caused by oxidative stresses, fuel availability, age, hormones, radiation, or drugs) will dictate and initiate changes in immune recognition and in the nature of the immune response. This has profound implications for controlling the symptoms of autoimmune diseases, for preventing graft rejection, and for targeting tumor cells for destruction.  相似文献   
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Summary Stability in storage and shipment of retinol, -tocopherol, vitamins B1, B2 and C in three foods was studied to assess the feasibility of certifying the vitamin content of three food RMs, whole milk powder (CRM 380), pork muscle (CRM 384) and freeze-dried haricot beans (CRM 383); these were recently certified for major dietary components and major elements. Interpretation of the long-term stability data was complicated by a dominant analytical variability over the measurement period. The long-term stability study (24 months) gave evidence of deterioration of vitamin B2 in pork muscle. The other vitamins studied seemed to be acceptably stable at –18°C and +4°C. Additional studies showed stability of retinol in milk powder for 34 months and of vitamin C in haricot beans for 31 months at –18°C and +4°C. Long-term storage seems to be possible at a temperature not higher than +4°C except for vitamin B2. A short-term stability study at +25°C and +30°C for 6 weeks showed acceptable stability of retinol and -tocopherol in milk powder (CRM 380) and of vitamin C in haricot beans (CRM 383). However, storage at +42°C induces degradation of retinol, -tocopherol and vitamin C.  相似文献   
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Molecular clips functionalized with two sodium or ammonium benzoate groups self-assemble in water by means of a hydrophobically driven dimerization reaction. Depending on the counter ions, this self-assembly stops at the stage of the dimer (sodium) or continues to generate largenanometer-sized aggregates (ammonium). The molecules in the latteraggregates are proposed to be `glued' together by multiplehydrogen bonds between the ammonium counter ions and the benzoategroups of the clips.  相似文献   
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A reversed-phase high-performance liquid chromatographic method for the separation of the most common and some less common genetic variants of the bovine caseins is described. When the method is used for analysing clarified skim milk, simultaneous identification of casein variants and major they protein variants can be effected in a single run. The potential of the method for quantitative application is discussed.  相似文献   
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In many practical situations scaling the data is necessary to solve linear programs. This note explores the relationships in translating the sensitivity analysis between the original and the scaled problems.  相似文献   
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Optical techniques are now broadly used in the field of experimental mechanics. The main advantages are they are non intrusive and no contact. Moreover optical techniques lead to full spatial resolution displacement maps enabling the computing of mechanical value also in high spatial resolution. For mesoscopic measurements, digital image correlation can be used. Digital holographic interferometry is well suited for quantitative measurement of very small displacement maps on the microscopic scale. This paper presents a detailed analysis so as to compare digital Fresnel holography and digital image-plane holography. The analysis is based on both theoretical and experimental analysis. Particularly, a theoretical analysis of the influence of the aperture and lens in the case of image-plane holography is proposed. Optimal filtering and image recovering conditions are thus established. Experimental results show the appropriateness of the theoretical analysis.  相似文献   
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Background  

Oral administration of BCG was the route initially used by Calmette and Guérin, but was replaced by intradermal administration in virtually all countries after the Lubeck accident. However, Brazil continued to administer oral BCG Moreau RDJ, which was maintained until the mid-1970s when it was substituted by the intradermal route. Although BCG vaccination has been used in humans since 1921, little is known of the induced immune response. The aim of this study was to analyse immunological responses after oral vaccination with M. bovis BCG Moreau RDJ.  相似文献   
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