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71.
[目的]观察复方甘草酸苷对慢性乙型肝炎患者血清病毒学标志的影响.[方法]采用复方甘草酸苷联合拉米夫定治疗30例慢性乙肝患者,并与30例拉米夫定单药治疗患者比较,观察治疗后血清病毒学标志及肝功能指标的变化.[结果]治疗12周时联合治疗组血清HBeAg/抗-HBe转换率明显高于对照组;治疗12周和24周时联合治疗组肝功能指标复常率明显高于对照组.[结论]复方甘草酸苷治疗慢性乙型肝炎可能有助于患者在拉米夫定治疗过程中早期发生HBeAg/抗-HBe血清转换.  相似文献   
72.
丁广义割圆序列的线性复杂度   总被引:1,自引:0,他引:1  
Minimal polynomials and linear complexity of binary Ding generalized cyclotomic sequences of order 2 with the two-prime residue ring Zpq are obtained by Bai in 2005. In this paper, we obtain linear complexity and minimal polynomials of all Ding generalized cyclotomic sequences. Our result shows that linear complexity of these sequences takes on the values pq and pq-1 on our necessary and sufficient condition with probability 1/4 and the lower bound (pq - 1)/2 with probability 1/8. This shows that most of these sequences are good. We also obtained that linear complexity and minimal polynomials of these sequences are independent of their orders. This makes it no more difficult in choosing proper p and q.  相似文献   
73.
开拓者的形象与足迹--新疆兵团中短篇小说创作纵论   总被引:1,自引:0,他引:1  
文章论述了兵团中短篇小说的发展历程."文革"前的作品文献价值大于艺术价值.进入新时期以后,恢复了新文学现实主义的优良传统,小说的描写领域呈现不断拓展的态势,力求塑造出丰满的、具有立体感的人物形象.  相似文献   
74.
S. Negassi 《Research Policy》2004,33(3):365-384
The scope of this paper is to report new empirical evidence on the determinants of R&D co-operation. Indeed, the literature on the capabilities of firms emphasises the role of knowledge in the performance and evolution of firms who use knowledge developed in others to build their own knowledge capital. R&D co-operation between firms is one of the many strategies by which this knowledge may be transmitted. Several theoretical models have stressed that R&D co-operation is more likely when the level of spillovers is high. While this supposition is used in many theoretical models, it has rarely been tested before. Our results do not lend strong support to this intuition. Indeed, our spillover variables (national pure spillovers, national rent spillovers and imports of machine tools), which were supposed to match the theoretical notion of spillovers used in these theoretical models have a positive but not a significant role when explaining R&D co-operation. The R&D co-operation increases with size and with R&D intensity, but not with market share. It also increases with the budget spent on paying license fees and on acquiring patents and labour from foreign firms. In this study, we also analyse the determinants of innovation. In more precise terms, we compare the effects of R&D co-operation to those played by traditional internal factors and those exerted by external, pure and rent spillovers on the innovation capacity of the firms. Our results show that the commercial success of innovations of French firms depends mainly on size, market share, R&D intensity and human capital. Inward FDI from industrialised countries exerts a positive and significant effect. The finding highlights the important role of the absorptive capacity of firms. Spillover measurements, such as the acquisition of machine tools, foreign patents, licenses, and technological opportunities have a positive impact on innovation.  相似文献   
75.
76.
常喜 《科技广场》2007,(1):207-208
微型打印机是各种智能化仪表、仪器及各种单片机系统的重要输出设备。本文介绍应用89C51单片机控制微型打印机实现打印功能的设计和实现方法,并给出89C51单片机控制微型打印机的硬件设计及其C语言软件的实现。  相似文献   
77.
本文探讨了设计网上银行支付系统所需要的安全技术,对支付系统的安全性进行了研究,设计了支付系统应具备的功能,设计了系统模型和流程,给出了一种网上银行B2C电子支付系统的安全、可靠,便捷的解决方案.  相似文献   
78.
The standard empirical framework for analysing the R&D-patents relationship is widened both by examining the different role of in-house and contracted R&D in the innovative performance of firms, and by considering patents and utility models counts as measures of innovation output. Patents and utility models are considered to approximate for significant and incremental innovations, respectively. Applying count data econometrics to a panel data set of Spanish manufacturing firms surveyed in the period 1990-1996, a transcendental production function is estimated, which allows for non-constant elasticities of the R&D inputs. The results indicate that significant innovations are mainly gestated in-house, whereas contracted R&D seems more orientated towards innovations of incremental nature.  相似文献   
79.
根据对Elatostema gagnepainianum H. Schröter模式材料的研究,为它指定了后选模式,并将其处理为藤麻Procris crenata C. B. Robinson的新异名。  相似文献   
80.
Knowledge-relatedness in firm technological diversification   总被引:4,自引:0,他引:4  
This paper claims that knowledge-relatedness is a key factor in affecting firms’ technological diversification. The hypothesis is tested that firms extend the range of their innovative activities in a non-random way. Specifically, we test the extent to which firms diversify their innovative activities across related technological fields, i.e. fields that share a common knowledge base and rely upon common heuristics and scientific principles. The paper proposes an original measure of knowledge-relatedness, using co-classification codes contained in patent documents, and examines the patterns of technological diversification of the whole population of firms from the United States, Italy, France, UK, Germany, and Japan patenting to the European Patent Office from 1982 to 1993. Robust evidence is found that knowledge-relatedness is a major feature of firms’ innovative activities.  相似文献   
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