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111.
本文以系统论为视角,在两化融合的内涵基础上,运用系统科学的原理和分析方法,分析了两化融合的系统性特征,然后根据分析两化融合关系作用机理,构建出基于系统论视角的两化融合影响要素系统模型,并针对该系统模型,从动力、支撑和环境等方面分析影响工业化与信息化融合的关键要素, 相似文献
112.
Microhabitat characteristics of blue grouse ( Dendragapus obscurus ) were analyzed in breeding and wintering habitats in southeastern Idaho. Breeding habitats typically were open sagebrush ( Artemisia spp.), mixed shrub, mountain mahogany ( Cercocarpus ledifolius ) , and maple ( Acer grandidentatum ) stands on east to south facing aspects of slopes below 2100 m elevation. Breeding blue grouse selected areas with approximately a 50:50 or greater open to cover ratio. Blue grouse selected areas with higher tree coverage than available on average within the mixed shrub vegetation type. Hens with broods preferred sites with relatively tall (>50 cm) herbaceous vegetation. During autumn and winter, blue grouse preferred high elevation (>2285 m) stands of open (50% tree cover) conifer. Douglas-fir ( Pseudotsuga menziesii ) were preferred as winter roost trees. Sites selected in winter had significantly more Douglas-fir than those selected in autumn. 相似文献
113.
对华罗庚、丘成桐、吴文俊、谷超豪四位中国数学大师的创新精神进行了全面的分析与阐释,在此基础上得到几点重要启示. 相似文献
114.
Lathrop SK Bloom SM Rao SM Nutsch K Lio CW Santacruz N Peterson DA Stappenbeck TS Hsieh CS 《Nature》2011,478(7368):250-254
The instruction of the immune system to be tolerant of self, thereby preventing autoimmunity, is facilitated by the education of T cells in a specialized organ, the thymus, in which self-reactive cells are either eliminated or differentiated into tolerogenic Foxp3(+) regulatory T (T(reg)) cells. However, it is unknown whether T cells are also educated to be tolerant of foreign antigens, such as those from commensal bacteria, to prevent immunopathology such as inflammatory bowel disease. Here we show that encounter with commensal microbiota results in the peripheral generation of T(reg) cells rather than pathogenic effectors. We observed that colonic T(reg) cells used T-cell antigen receptors (TCRs) different from those used by T(reg) cells in other locations, implying an important role for local antigens in shaping the colonic T(reg)-cell population. Many of the local antigens seemed to be derived from commensal bacteria, on the basis of the in vitro reactivity of common colon T(reg) TCRs. These TCRs did not facilitate thymic T(reg)-cell development, implying that many colonic T(reg) cells arise instead by means of antigen-driven peripheral T(reg)-cell development. Further analysis of two of these TCRs by the creation of retroviral bone marrow chimaeras and a TCR transgenic line revealed that microbiota indigenous to our mouse colony was required for the generation of colonic T(reg) cells from otherwise naive T cells. If T cells expressing these TCRs fail to undergo T(reg)-cell development and instead become effector cells, they have the potential to induce colitis, as evidenced by adoptive transfer studies. These results suggest that the efficient peripheral generation of antigen-specific populations of T(reg) cells in response to an individual's microbiota provides important post-thymic education of the immune system to foreign antigens, thereby providing tolerance to commensal microbiota. 相似文献
115.
基于计算机网络的现代远程教育是随着现代信息技术的发展而产生的一种新型教育方式,发展远程教育是现代教育的需要.论及了我国目前远程教育存在的问题及对发展远程教育的思考. 相似文献
116.
Summary Treatment of 3T3 cell plasma membranes with glycosidase enzymes decreased their ability to inhibit cell growth and also decreased their binding to 3T3 cells. This suggests that carbohydrate is required for complete function of inhibitory activity and that inhibition is associated with membrane adhesion. 相似文献
117.
Monoclonal antibodies distinguish between storage and secreted forms of eosinophil cationic protein 总被引:6,自引:0,他引:6
The toxic effects of eosinophils on parasites and cells are due largely to the secretion of various granule proteins, following stimulation. In order to study this secretory process (degranulation) further, we have raised mouse monoclonal antibodies against both human eosinophil granule extracts and secretion products. From immunocytochemical studies it appears that one antibody, EG1 , recognized both the storage and secreted forms of eosinophilcationic protein (ECP), whereas antibody EG2 only bound to ECP during secretion (and extraction). This antibody also bound to eosinophil protein-X (EP-X). As both antibodies stained eosinophils in formalin-fixed tissues, they were used to demonstrate sites of eosinophil activation and secretion in chronic urticaria. The capacity of monoclonal antibodies to detect differences between storage and secreted forms of proteins is an important property of these reagents with many potential applications in cell biology. 相似文献
118.
J. D. Gupta V. J. Peterson J. D. Harley 《Cellular and molecular life sciences : CMLS》1973,29(6):664-665
Résumé Dans le cristallin et les erythrocytes de poussins à l'état embryonnaire et quelques jours après l'éclosion, l'activité de l'ATPase est beaucoup plus intense que chez d'autres animaux. Ce fait correspond bien à la forte incorporation de Rb86 dans leur cristallin.
This work was supported by grants from the National Health and Medical Research Council of Australia, the Clive and Vera Ramaciotti Foundation and the Helena Rubinstein Foundation. Inc. J. D. G. was supported by a fellowship from ATN Channel 7, Sydney. 相似文献
This work was supported by grants from the National Health and Medical Research Council of Australia, the Clive and Vera Ramaciotti Foundation and the Helena Rubinstein Foundation. Inc. J. D. G. was supported by a fellowship from ATN Channel 7, Sydney. 相似文献
119.
我国工业化与城市化关系的互动与协调 总被引:1,自引:0,他引:1
巴春生 《曲靖师范学院学报》2003,22(1):6-9
城市化是人类社会发展的必然趋势,是人类社会明进步的基本标志,世界各国实现城市化的历史与现实表明:工业化是城市化的直接原因和物质载体,而城市化又是工业化的必然结果。两相互联系,相互促进。我国要实现城市化的历史重任,必须正确处理工业化与城市化的关系,促进工业化与城市化的协调发展。 相似文献
120.