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排序方式: 共有387条查询结果,搜索用时 15 毫秒
61.
AJ Ferreira WP Elias JS Pelayo R Giraldi MZ Pedroso IC Scaletsky 《Canadian Metallurgical Quarterly》1997,19(4):285-288
In the present study, in order to get a better insight into the mechanism of action of cyclophosphamide (CY) in rheumatoid arthritis (RA), we monitored the changes in lymphocytes' expression of leukocyte function associated antigen 1 (LFA-1). A group of 28 patients with refractory severe RA were treated with CY and methylprednisolone (MO) intravenously. Using flow cytometry we evaluated the changes in LFA-1 molecule expression on peripheral lymphocytes. In the analyzed group of patients the proportion of LFA-1 "dim" cells was reduced. After the treatment the ratio was partly normalized. Twelve months after cessation of the therapy high proportion of LFA-1 "dim" was observed only among CY/MP treated patients. The changes were related to clinical improvement. Based on the obtained data, it seems, that the treatment affecting the expression of LFA-1 may slow down lymphocyte migration and by that limit chronic inflammation within the synovium. 相似文献
62.
A. Tomala W.S.M. Werner I.C. Gebeshuber N. Drr H. Stri 《Tribology International》2009,42(10):1513-1518
The aim of present study was to find out the influence of oxygen and nitrogen containing ethanolamine oligomers on the tribological behavior. X-ray photoelectron spectroscopy (XPS) was used to obtain insight into the molecular mechanisms leading to the macroscopic lubricity. Monomolecular lubricant films were deposited onto ultra thin copper films sputtered onto silicon wafers. Surfaces covered with the three ethanolamine oligomers were investigated by XPS before and after tribological tests, performed with the translatorily oscillating test machine and Falex micro-tribometer.The structure of the molecular film is elucidated using angular resolved X-ray photoelectron spectroscopy with a prototype preparation chamber, permitting the transfer of samples from liquid to the analysis chamber under Helium protective gas preventing exposure to ambient conditions. Solutions with a concentration of 250 ppm of the respective ethanolamine oligomers in double distilled water were transferred into the adsorption device, which is an extension of the spectrometer. Results show that compounds bond to copper and steel surface by N atom present in ammonia group and hydroxyl group are oriented on the top layer of tribofilm, this highest group influence lubricity properties. 相似文献
63.
Jeremie Bouchaud 《集成电路应用》2012,(5):11-12
MEMS传感器除了传统应用如喷墨打印头、投影仪、麦克风、汽车等领域,它还广泛应用在手机、平板电脑等移动终端上,可为设备添加更多智能化功能。据IHS iSuppli公司的MEMS市场调查显示,2011年最大的十家MEMS厂商的合计营业收入为47亿美元,比2010年的42亿美元增长12%。德州仪器继续稳居全球最大的MEMS器件制造商地位,在激烈竞争中保住了冠军位置,惠普仍然屈居第二。十大MEMS厂商中其他几家按降序排列依次是博世、意法半导体、佳能、松下、电装、楼氏、ADI和爱普生。飞思卡尔半导体原来也位于十大厂商行列,但2011年排名第十一,跌出了前十之列。 相似文献
64.
Rhoda Alexander 《集成电路应用》2012,(6):4-5
虽然基于Android系统的平板电脑增长快速,但目前看来苹果仍将保持绝对领先的态势。随着英特尔超极本的推出以及Windows8面市,PC型平板或将成为平板市场上一股新的力量。据IHS iSuppli公司全球平板电脑市场追踪报告显示,2012年苹果公司将以其iPad系列产品轻松保持在全球平板电脑市场的绝对领先地位,尽管一众Android产品和基于PC的平板产品也在努力进入这个迅速增长的市场。今年包括媒体平板和PC型平板在内的平板电脑销量将增加到1.266亿台,比2011年的 相似文献
65.
Randy Lawson 《集成电路应用》2012,(2):8-8
由于价格压力沉重和电视销售低迷,去年电视主板上使用的半导体销售额萎缩,并迫使一些知名厂商永远退出该产业。不过随着新功能的推出,半导体企业仍存在增长机会。 相似文献
67.
Glomerulopathy with predominant fibronectin deposits (GFD) is a newly recognized autosomal dominant renal disease that leads to albuminuria, microscopic hematuria, hypertension, renal tubular acidosis type IV, and end-stage renal disease in the second to fourth decade of life. Light microscopy documents extensive deposits in the subendothelial space, which on electron microscopy consist of non-oriented 12 x 125 nm fibers. Deposits are strongly immunoreactive for antibodies to fibronectin. We examined the hypothesis that a genetic defect in the gene for fibronectin is responsible for the disease. In a 197 member pedigree, 13 relatives developed end-stage renal failure from the disease. In 99 individuals haplotype analysis was performed using 6 microsatellite markers spanning a > 56 cM interval in chromosome region 2q34, where fibronectin, villin, and desmin map in close proximity. Haplotype analysis resulted in exclusion of the whole range of 78 cM covered by the markers examined. This result excludes fibronectin, villin, and desmin from being the causative genes for GFD in this large kindred. 相似文献
68.
本文提出在ASIC综合技术中基于标准单元库的多级逻辑函数分解技术。分解过程利用单元库函数真值矩阵及各分解部分用标准单元实现的难易程度、逻辑级数来评价、引导分解得到的多级逻辑易于用标准单元组合实现。使用的标准单元类型具有较大程度的相似性,有利于基于标准单元布局布线软件进一步减少芯片面积。 相似文献
69.
SH Kim KH Chang IC Song MH Han HC Kim HS Kang MC Han 《Canadian Metallurgical Quarterly》1997,204(1):239-245
An experiment is reported examining the relation of implicit grammar learning and series completion tasks to a standard measure of psychometric intelligence, the Wechsler Adult Intelligence Scale-Revised (WAIS-R; D. Wechsler, 1981). The results replicate and extend an earlier study by A. S. Reber, F. F. Walkenfeld, and R. Hernstadt (1991) and provide the following support for the differences between explicit and implicit tasks: (a) The implicit task was less strongly related to Full Scale IQ, and (b) the implicit task appeared to be independent of age. The implicit and explicit tasks exhibited a quite different pattern of relations to the factors known to underlie WAIS-R performance. Although both tasks showed significant links with a Perceptual Organization factor, only the series completion task showed a significant link with the Attention factor. 相似文献
70.
PURPOSE: Supraspinal sensorimotor maps contain adjacent representations of the hand and face. These experiments were designed to determine whether interactions between the representations could be detected at the periphery. METHODS: Simultaneous EMG recordings were made from orbicularis oculi and wrist flexor during three conditions, with 50 repetitions each: during exposure to an auditory cue; responding to the auditory cue by wrist flexion; and performing a self-paced wrist flexion in the absence of an auditory cue. RESULTS: In 8 of 10 healthy volunteers, the rectified, averaged EMGs showed small but consistent increases in orbicularis oculi activity during wrist flexion in the two tasks involving that movement, but not in the auditory task alone. CONCLUSION: In one or more of the central sensorimotor maps, voluntary activation of the wrist flexor representation is accompanied by liminal activation of a nearby facial representation which projects to the motoneurons of orbicularis oculi. 相似文献