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1.
Genetic variation in the angiotensin II type 1 receptor (AT1R) has an important effect on the outcome of acute coronary syndrome (ACS) initiated treatment with captopril. This study aims to investigate the impact of genetic polymorphism of AT1R (rs5186 and rs275651) on the ACS outcome in Iraqi patients treated with captopril. A total of 250 Iraqi individuals with ACS were included in this case—control study and they were divided into two study groups; Study group 1 included 125 participants who were prescribed captopril, 25 mg twice daily and study group 2 included 125 participants who received no captopril as part of their ACS treatment (control study). The AT1R gene (rs5186) CC genotype was found to be associated with ST-elevation myocardial infarction (STEMI) (Odd’s ratio (O.R) = 1.2, P = 0.7), while AC was associated with Non-ST-elevation myocardial infarction (NSTEMI) and unstable angina (UA) (O.R = 1.2, P = 0.8). AC genotype is more prone to have Percutaneous coronary intervention (PCI) after ACS attack (O.R = 1.2, P = 0.6). CC genotype had a risk to get less improvement (O.R = 1.6, P = 0.5), so might require higher doses of captopril during acute coronary insult. The AT1R gene (rs275651) AA genotype was associated with UA (O.R = 1.3, P = 0.9). AA and AT genotypes were more prone to have PCI after ACS attack (O.R = 3.9 P = 0.2, O.R = 3.5, P = 0.3 respectively) and thus requiring higher doses of captopril. We conclude that the AT1R rs5186, rs275651 genetic polymorphisms might partially affect the clinical outcome of ACS patients treated with captopril and might have captopril resistance which requires higher doses.  相似文献   
2.
In this ITEMS module, we introduce the generalized deterministic inputs, noisy “and” gate (G‐DINA) model, which is a general framework for specifying, estimating, and evaluating a wide variety of cognitive diagnosis models. The module contains a nontechnical introduction to diagnostic measurement, an introductory overview of the G‐DINA model, as well as common special cases, and a review of model‐data fit evaluation practices within this framework. We use the flexible GDINA R package, which is available for free within the R environment and provides a user‐friendly graphical interface in addition to the code‐driven layer. The digital module also contains videos of worked examples, solutions to data activity questions, curated resources, a glossary, and quizzes with diagnostic feedback.  相似文献   
3.
营销组合4P范式的不可替代性   总被引:8,自引:0,他引:8  
吴长顺  朱玲 《科技管理研究》2007,27(6):215-217,227
营销组合范式从4P发展至4C、4R,引起学者的热烈反应和广泛讨论。在前人研究的基础上,将4P、4C、4R从产品、定价、渠道、促销四个方面进行对比,得出4P理论是具有实操性的营销组合工具,能为消费者提供实际的价值方案,更符合营销工具的实质,是营销学不可替代的理论根基。  相似文献   
4.
The purpose of this paper is to examine whether the technical universities have been more successful in facilitating the spillover and commercialization of knowledge. We compare the impact of technical and general universities on the performance of knowledge-based firms. Based on a unique data set consisting of publicly held high technology firms, the empirical evidence suggests that, in fact, firm performance is not influenced by the type of university. Technical universities do not have a differential impact on firm performance from more general universities.  相似文献   
5.
赫斯特指数的计算过程需要对研究的时间序列数据进行分组,而不同的分组情况对赫斯特指数会产生不同的影响。以深圳股票市场1997-2001年的日收盘成分指数为例,表明组内数据为15个左右时计算的赫斯特指数的可信度较高,但不同的分组方法却不会使结论发生质的变化,仅是量的改变。  相似文献   
6.
重庆市主城区降雨侵蚀力特征分析   总被引:6,自引:0,他引:6  
文章根据重庆市自建气象站以来的降雨过程资料(1954~2001),对重庆市主城区降雨侵蚀力(R)及其特征进行了研究和分析。研究结果表明,研究区降雨侵蚀力主要集中在5月~9月,48年里研究区年降雨侵蚀力值变幅均较大,但从整体上来看,趋势保持平稳,其离差系数Cv和变化趋势系数r值分别为0.65和0.061; 研究区次降雨量与次降雨侵蚀力,月降雨量与月降雨侵蚀力均呈乘幂关系,而年降雨量与年降雨侵蚀力呈现指数关系; 为了解决在降雨资料不足的情况下对降雨侵蚀力的计算,文章利用不同的降雨资料与侵蚀力之间进行相关分析,最终确定了适合研究区的两种降雨侵蚀力简易算法。  相似文献   
7.
赫斯特指数的分析与应用   总被引:2,自引:0,他引:2  
基于重标极差(R/S)分析基础上的赫斯特指数(H)是用来描述和标度传统的有效市场假说(EMH)是否成立的一个指标,本文以我国深圳成分指数为研究对象,通过对深成指的赫斯特指数的研究,结果表明该股票指数遵循有偏的随机游走(分形布朗运动)而非传统的随机游走模式。  相似文献   
8.
In this paper, we investigate the relationship between location patterns, innovation processes and industrial clusters. In order to do this we extend a transactions costs-based classification into a knowledge-based taxonomy of clusters, along the lines suggested by a critical revision of the main assumptions underlying most of the existing literature on spatial clusters. Our arguments show that the transactions costs approach and the innovation and technological regimes framework are broadly consistent, and that real insights into the microfoundations, nature, and evolution of clusters can be provided by these classification systems.  相似文献   
9.
We investigate the impact of knowledge spillovers and R&D cooperation on innovation activities in three German regions. We begin by estimating the knowledge-production function in order to test for interregional difference with regard to the efficiency of innovation activities. In a second step, we analyze the contribution of spillovers from R&D effort of other private firms and of public research institutions to explain these differences. The inclusion of variables for R&D cooperation in the model indicates that R&D cooperation is only of relatively minor importance as a medium for knowledge spillover.  相似文献   
10.
Looking at micro-data on the networks of inventors of a French science university, we investigate whether the kind of cognitive relationships between researchers influences the geography of their collaborations.The hypothesis we test (and confirm empirically) is that academic knowledge diffuses in a restricted geographic area when the connected researchers belong to epistemic communities, whereas communities of practice entail less localised effects. We also show that institutionally mixed research teams do not impede large knowledge diffusion.  相似文献   
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