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101.
A research study and discussion of antiinterferon immunoglobulin in the treatment of rheumatoid arthritis and systemic lupus erythematosus, and its possible value in the treatment of allergic diseases, autoimmune diseases and other diseases where it is presumed there may be an autoimmune genesis.  相似文献   
102.
高温焙烧高钛渣工艺的试验研究   总被引:3,自引:1,他引:3  
以云南地区钛铁矿富集得到的高钛渣为原料,置于加热装置内焙烧,在1000℃下加热处理20min,利用XRD、SEM研究了高温焙烧对高钛渣相组成和微观结构的影响.结果表明:在高温条件下高钛渣中的锐铁型TiO2转化为金红石型TiO2.提出了一种高温焙烧高钛渣的新工艺,从生产源头消除了对环境的污染,实现钛资源的可持续发展.  相似文献   
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组合圆锥-圆柱形壳形式的钢贮罐是一种常见的用于储存液体的压力罐。大部分此类压力罐的破坏都由于钢壳的失稳而引起。引起这些破坏的主要原因是没有适当的设计方法来对这类结构进行设计。在本次研究中,提出了简化的设计方法,以保证静水加载的组合钢罐在发生屈曲时的安全。应用非线性有限元模型进行数值模拟,对大变形和几何缺陷对钢罐稳定性的破坏作用进行分析。采用有限元计算结果与非线性回归分析建立函数,将壳的总应力与膜应力关联起来。采用算例说明了所提议设计方法的应用。  相似文献   
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To investigate the extent to which inhibitory interneurons control impulse flow through the dentate gyrus during spatial learning in an exploration task, dentate field potentials were recorded in response to paired stimulation of the perforant path while rats rested or explored. Recurrent inhibition of the granule cells was measured as the reduction of the second waveform when a population spike was present in the first. Both the population spike and the field EPSP (fEPSP) were suppressed at interstimulus intervals shorter than approximately 40 msec. Consistent differences were observed between potentials recorded at equivalent brain temperature in the exploration and resting (reference) conditions. During exploration, the fEPSP of the second (test) waveform was reduced further compared with reference potentials with a similar response to the first (conditioning) stimulus. This reduction was observed only when the first pulse elicited a population spike. The population spike of the second waveform was facilitated compared with reference potentials with similar fEPSP slopes. These observations suggest that exploration is coupled to increased inhibition on the perforant-path terminals or the dendrites of the granule cells, whereas the inhibition on the somata is decreased. The two phenomena were not correlated and followed different time courses. The suppression of the fEPSP decayed gradually, although it was still present at 15 min, whereas the facilitation of the population spike was stable. Together, these changes, which likely involve different populations of interneurons, may focus and amplify incoming signals from the entorhinal cortex.  相似文献   
108.
The paper presents experimental and clinical findings of the new antiarrhythmic drug nibentan. The agent was found to be a class-III antiarrhythmic agent in terms of its electrophysiological effects and an inhibitor of the delayed rectifier potassium current in terms of its effects on the ionic channels of cardiomyocytes. The clinical trial of nibentan shows that the drug is highly effective (in 70-100% of cases) in patients with atrial flutter and fibrillation and in those with supraventricular tachycardia and it is less effective in suppressing ventricular premature contractions and tachycardia. The rate of arrhythmogenic effects produced by the drug was inversely related to its antiarrhythmic action. Nibentan has been approved for clinical use.  相似文献   
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The nucleotide sequences of the genomic RNAs of two hordeiviruses, poa semilatent virus (PSLV) and lychnis ringspot virus (LRSV), were determined. The genome organization of both viruses is similar to that of the type hordeivirus, barley stripe mosaic virus (BSMV). Comparisons of the amino acid sequences of the hordeivirus replicase components revealed a high level of sequence similarity to those of soil-borne wheat mosaic virus (SBWMV), peanut clump virus (PCV), and Indian peanut clump virus. The cysteine-rich gamma b proteins of hordeiviruses are similar to those of SBWMV, PCV, and tobraviruses. Analysis of cis-acting elements in the genomes of the three hordeiviruses revealed conservation of putative core elements of subgenomic RNA promoters. Complex patterns of conservation were also found in the 5'-untranslated regions of hordeivirus genomic RNAs alpha, beta, and gamma.  相似文献   
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