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21.
Summary The nature of antigen Dd, an antigen present in the extracts of human dandruff which precipitates human sera selectively, and antibodies reacting with it are reported.This work was supported through U.G.C. Grant No. F.23-230/75/SR II. H.K. participated in this study, first as J.R.F. of U.G.C. and then as S.R.F. of I.C.M.R. We are grateful to Dr Baruch S. Blumberg for his invaluable suggestions and to Professor H. Walter for the gift of IgG, IgM and IgA immune sera.  相似文献   
22.
A topoisomerase II inhibitor, novobiocin, and a deacetylase inhibitor, butyrate, synergistically transformed human liver cells into fibroblast-like cells. This morphological change was associated with an increased production of procollagen type III peptide and a simultaneous assembly of actin, tubulin, vimentin and cytokeratin. Novobiocin and butyrate had no marked effect on the phosphorylation state of cytokeratin proteins, but synergistically enhanced [3H]acetate uptake. From these results, it can be speculated that protein acetylation plays an important role in inducing the assembly of cytoskeletal proteins and the morphological transformation of human liver cells.  相似文献   
23.
F K Gyoeva  V I Gelfand 《Nature》1991,353(6343):445-448
Intermediate filaments in most types of cultured cells coalign with microtubules. Depolymerization of microtubules results in collapse of vimentin and desmin intermediate filaments to the nucleus where they form a perinuclear cap. Collapse can also be induced by microinjection of antibodies against intermediate filament or microtubule proteins. Thus, two filament systems interact with each other. But the molecules mediating this interaction are unknown. One of the candidates for this role is a microtubule motor kinesin. Recent data showed that kinesin is involved in the plus end-directed movement of the membranous organelles along microtubules such as radial extension of lysosomes in macrophages and centrifugal movement of pigment in melanophores. Here we report that injection of the anti-kinesin antibody into human fibroblasts results in the redistribution of intermediate filaments to a tight perinuclear aggregate but had no effect on the distribution of microtubules. Thus, kinesin is involved not only in organelle movement but also in interaction of the two major cytoskeletal systems, intermediate filaments and microtubules.  相似文献   
24.
本文用扫描电镜(SEM)和示差扫描量热法(DSC)研究了XeCl准分子激光辐照Fe_(81.5)P_(18.4)Yb_(0.1)非晶合金的晶化特征。结果发现,辐照样品的断面上有类冲击波纹样的层状规则的晶粒分布,其晶粒尺寸由辐照表面向样品内部逐渐减小,最后是近纳米尺度的微晶排布,样品的热稳定性也明显改善。  相似文献   
25.
Summary Using flurbiprofen, a chiral anti-inflammatory and analgesic 2-arylpropionic acid derivative, the enantiomers of which are not converted to each other (less than 5%) in rats or man, we obtained evidence that prostaglandin synthesis inhibition is primarily mediating the anti-inflammatory activity but prostaglandin synthesis independent mechanisms contribute to the analgesic effects. Thus, the S-form inhibited prostaglandin synthesis, inflammation and nociception in rats. The R-form had much less effect on prostaglandin synthesis and did not affect inflammation. It did, however, block nociception in rats almost as potently as the S-form. S-flurbiprofen, in contrast to the R-form, was clearly ulcerogenic in the gastrointestinal mucosa. These results indicate additional molecular mechanisms of analgesia and suggest the use of R-arylpropionic acids as analgesics.  相似文献   
26.
翟展胜 《太原科技》2003,(2):62-62,64
通过分析影响光缆接续质量的因素,从减少本征影响、克服技术因素、优化综合处置、减弱和避开环境影响4方面针对性地提出了实际施工中应采取的施工方法,以控制和减小不利影响,提高光缆工程的接续质量,为建设高质量传输线路提供有力保证。  相似文献   
27.
The genetic engineering of production traits in domestic animals   总被引:1,自引:0,他引:1  
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28.
We develop in this paper an efficient way to select the best subset threshold autoregressive model. The proposed method uses a stochastic search idea. Differing from most conventional approaches, our method does not require us to fix the delay or the threshold parameters in advance. By adopting the Markov chain Monte Carlo techniques, we can identify the best subset model from a very large of number of possible models, and at the same time estimate the unknown parameters. A simulation experiment shows that the method is very effective. In its application to the US unemployment rate, the stochastic search method successfully selects lag one as the time delay and five best models from more than 4000 choices. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
29.
30.
1 Results Classic oxidants require rigorous control of the experimental conditions added with the problem of lack of selectivity. Catalysis by transition metals with environmentally safe oxidants provides synthetic routes to minimize pollution by giving environmental benign by-products. Fe (Ⅵ) is a powerful and a selective oxidant with Fe(Ⅲ) as a by-product, while hydrogen peroxide is clean with water as the only by-product. Separation of sodium or potassium ferrates requires tedious processes. Associat...  相似文献   
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