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71.
The predominance of Th2 cytokine-secreting pattern in allergic asthma has been known as a cause and an accelerating factor, and Th1 suppresses these allergic phenomena, but the role of Th0 clones is obscure. Because Th1/Th2 differentiation has been determined by cytokine environment, we investigated how mite-specific helper T cells stimulated in different cytokine environments actually influenced IgE and IgG4 synthesis, which are known to be regulatory immunoglobulins for allergic response. Th0 clones, which were mainly established in the presence of IL-12, provided a great deal of help for IgG4 and IgG1 synthesis, but did not provide help for IgE synthesis, whereas Th2 clones helped IgE synthesis prominently, and IgG4 and IgG1 synthesis marginally. These characteristics of Th0 clones were also true for Th0 clones obtained from patients who were successfully treated with desensitization therapy. Furthermore, the differences in helper activity between Th0 and Th2 clones were not ascribed solely to soluble factors. These data indicate that IgE and IgG4 synthesis is differentially regulated by antigen-specific T cells, and that conversion or selection from Th2 to Th0 by the addition of IL-12 may exhibit therapeutic effects.  相似文献   
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The goal of this study was to test whether 1st-order information, which does not account for acceleration, is used (a) to estimate the time to contact (TTC) of an accelerated stimulus after the occlusion of a final part of its trajectory and (b) to indirectly intercept an accelerated stimulus with a thrown projectile. Both tasks require the production of an action on the basis of predictive information acquired before the arrival of the stimulus at the target and allow the experimenter to make quantitative predictions about the participants' use (or nonuse) of 1st-order information. The results show that participants do not use information about acceleration and that they commit errors that rely quantitatively on 1st-order information even when acceleration is psychophysically detectable. In the indirect interceptive task, action is planned about 200 ms before the initiation of the movement, at which time the 1st-order TTC attains a critical value. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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This study evaluated the meat quality of grazing suckling calves (GR), suckling plus supplemented calves (SUP) and weaned calves finished on concentrates (FIN) and the color evolution of meat packaged in film (FILM), modified atmosphere packaging (MAP) and vacuum packaging (VAC). Intramuscular fat was quite low for all treatments and GR meat had greater percentages of PUFA and lower SFA, MUFA and n6/n3 than SUP and FIN. FIN and SUP meat had more L* and was more tender when aged than GR. GR meat was tough and dark. The packaging system was more influential on meat color than the feeding management. VAC had the lowest values of metmyoglobin when aged. MAP had the greatest L* and hue angle and the lowest redness after 13 d of aging, thus MAP was the packaging with the shortest shelf life.  相似文献   
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The role of ferric oxide nanoparticles on the lubricating characteristics of passivating films formed on stainless steel (SS) was discussed in this study. The tribo-electrochemical behavior of mirror-like polished AISI 304 SS, used as an exemplary material, was evaluated in various electrolytes by means of a simulated chemical–mechanical polishing process in laboratory scale. It was clearly demonstrated that a suitable combination of abrasives (ferric oxide nanoparticles) and an oxidizer (nitric acid) can act as an effective lubricant that lowers the friction and wear of the AISI 304 SS surfaces. The excellent lubricating and anti-corrosion properties shown by a slurry containing a high content of ferric oxide nanoparticles at high nitric acid concentrations were attributed to the formation of a stable and robust passive film that was composed of chromium oxide and a mixture of iron oxides. The lack of ferric oxide nanoparticles in two solutions containing nitric acid of different concentrations led to pitting corrosion and abrasive wear. When low concentrations of both ferric oxide nanoparticles and nitric acid were used, wear-accelerated corrosion became the dominant mechanism that was caused by the presence of third-body wear particles in the contact zone.  相似文献   
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A temporal blackboard for a multi-agent environment   总被引:2,自引:0,他引:2  
The multi-agent system paradigm emerges as an interesting approach in the Knowledge Based System (KBS) field, when distributed problem-solving techniques are required for solving problems that can be represented as a collection of groups of cooperating intelligent individuals. A key concept in the multi-agent systems is the interaction between agents. On the other hand time plays a crucial role in a wide range of KBS applications. Temporal reasoning and representations consists of formalizing the notion of time and providing means to represent and reason about the temporal aspects of knowledge. This paper presents a framework for agent communication based on the blackboard paradigm which is able to manage temporal information, and it provides its multiple access and coherence management protocols.  相似文献   
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To analyse the relationship between age, glucose tolerance, beta-cell function, and insulin sensitivity in preclinical states of non-insulin-dependent (Type 2) diabetes mellitus (NIDDM), we have done a cross-sectional, age-stratified analysis of 86 non-diabetic first-degree relatives of NIDDM patients and 49 controls with similar age, sex, and BMI. A 5 mg kg ideal body weight-1 min-1 for 60 min of continuous infusion of glucose with model assessment (CIGMA) of serum glucose and C-peptide values at the end of the infusion was used to determine glucose tolerance and beta-cell function. Insulin sensitivity was estimated by modelling basal serum glucose and insulin values. Relatives and controls were divided into tertiles on the basis of age. Relatives had higher basal (5.3 vs 5 mmol l-1, p = 0.02) and achieved serum glucose (9.1 vs 8.4 mmol l-1, p = 0.01), lower beta-cell function (128 vs 145%, p = 0.007), and lower insulin sensitivity (37 vs 43%, p = 0.002). Beta-cell function declined with age in relatives (from 139% in young subjects to 134% in intermediate subjects and to 111% in older subjects, p = 0.002) and this decline was associated with an increase in basal serum glucose (from 5.1 to 5.3 and to 5.7 mmol l-1, p = 0.000) and achieved glucose (from 8.3 to 9.1 and to 9.3 mmol l-1, p = 0.038), without significant changes in insulin sensitivity. These trends were observed even after the exclusion of subjects with mild glucose intolerance. We conclude that both beta-cell dysfunction and insulin resistance are present in first-degree relatives of NIDDM. The progression of beta-cell dysfunction and glucose intolerance with age suggests that beta-cell dysfunction is the key factor in the apparition and progression of the disease.  相似文献   
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