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951.
Homocysteine(Hcy) has been implicated as a novel risk factor of Coronary Artery Disease (CAD) among Asian Indians, but many studies done in India failed to reveal any direct correlation. It has also been reported that Folic acid and Vitamin B12 levels inversely affect serum levels of homocysteine. In this study, we looked at the levels of homocysteine among patients with CAD. The effect of Vitamin B12, Folate and other risk factors on homocysteine levels were also evaluated. Mean homocysteine levels in cases (22.81±13.9, n=70) were significantly higher (p=<0.001) than the controls (7.77±7.3, n=70). However no statistically significant correlation could be deduced between homocysteine Vitamin B12, and Folate. Cumulative analysis have indicated an increase in homocysteine levels among patients with CAD with every additional risk factor.  相似文献   
952.
Acute coronary syndrome (ACS) is a term for a range of clinical signs and symptoms suggestive of myocardial ischemia. It results in functional and structural changes and ultimately releasing protein from injured cardiomyocytes. These cardiac markers play a major role in diagnosis and prognosis of ACS. This study aims to assess the efficacy of heart type fatty acid binding protein (h-FABP) as a marker for ACS along with the routinely used hs-TropT. In our observational study, plasma h-FABP (cut-off 6.32 ng/ml) and routinely done hs-Trop T (cutoff 0.1 and 0.014 ng/ml) were estimated by immunometric laboratory assays in 88 patients with acute chest pain. Based on the clinical and laboratory test findings the patients were grouped into ACS (n = 41) and non-ACS (n = 47). The diagnostic sensitivity, specificity, NPV, PPV and ROC curve at 95 % CI were determined. Sensitivity of hs-TropT (0.1 ng/ml), hs-TropT (0.014 ng/ml) and h-FABP were 53, 86 and 78 % respectively and specificity for the same were 98, 73 and 70 % respectively. Sensitivity, specificity and NPV calculated for a cut-off combination of hs-TropT 0.014 ng/ml and h-FABP was 100, 51 and 100 % respectively. These results were substantiated by ROC analysis. Measurement of plasma h-FABP and hs-TropT together on admission appears to be more precise predictor of ACS rather than either hs-Trop T or h-FABP.  相似文献   
953.
The web creates manyopportunities for encroachment on intellectualproperty including trademarks. Our principaltask in this paper is an investigation into anunusual form of such encroachment: theimproper use of metatags. A metatag is a pieceof HTML code that provides summary informationabout a web page. If used in an appropriatemanner, these metatags can play a legitimaterole in helping consumers locate information. But the ``keyword'' metatag is particularlysusceptible to manipulation. These tags can beeasily abused by web site creators anxious tobait search engines and bring scores ofvisitors to their sites. The law aboutmetatags is far from settled and many legalscholars are uncomfortable with the conclusionthat the unauthorized use of a trademark in ametatag represents infringement. How should weassess this practice known as ``spamdexing'' froma normative perspective? Is it commercial fairplay or something more sinister? We make thecase here that there are salient moral problemswith spamdexing since it exploits thereputational goodwill of trademark owners andconfuses consumers. It violates basic moralduties and it flouts the golden rule principle. Hence unauthorized use of a competitor'strademark in a metatag is not morallyacceptable.  相似文献   
954.
This paper examines the meaning of context in relation to ontology based query expansion and contains a review of query expansion approaches. The various query expansion approaches include relevance feedback, corpus dependent knowledge models and corpus independent knowledge models. Case studies detailing query expansion using domain-specific and domain-independent ontologies are also included. The penultimate section attempts to synthesise the information obtained from the review and provide success factors in using an ontology for query expansion. Finally the area of further research in applying context from an ontology to query expansion within a newswire domain is described.  相似文献   
955.
This paper investigates the effects of a magnetic field on the free convective flow of a viscous, incompressible, dissipative fluid through a porous medium, occupying a semi-infinite region of the space bounded by an infinite vertical and porous plate. The plate is subjected to a normal suction velocity and the heat flux at the plate is constant. The magnetic field is of uniform strength and is applied perpendicular to the plate. An analytical solution to the problem is obtained. The influence of the magnetic parameter (M) and permeability parameter (K) is discussed for the case of air (P = 0.71) when the plate is subjected to a constant suction velocity and is being cooled by free convection currents.  相似文献   
956.
In this paper, we focus on the potential innovative benefits to corporate venture capital (CVC), i.e. equity investments in entrepreneurial ventures by incumbent firms. We propose that corporate venture capital programs may be instrumental in harvesting innovations from entrepreneurial ventures and thus an important part of a firm's overall innovation strategy. We hypothesize that these programs are especially effective in weak intellectual property (IP) regimes and when the firm has sufficient absorptive capacity. We analyze a large panel of public firms over a 20-year period and find that increases in corporate venture capital investments are associated with subsequent increases in firm patenting.  相似文献   
957.
The performance of parallel query processing in a cluster of index servers is crucial for modern web search systems. In such a scenario, the response time basically depends on the execution time of the slowest server to generate a partial ranked answer. Previous approaches investigate performance issues in this context using simulation, analytical modeling, experimentation, or a combination of them. Nevertheless, these approaches simply assume balanced execution times among homogeneous servers (by uniformly distributing the document collection among them, for instance)—a scenario that we did not observe in our experimentation. On the contrary, we found that even with a balanced distribution of the document collection among index servers, correlations between the frequency of a term in the query log and the size of its corresponding inverted list lead to imbalances in query execution times at these same servers, because these correlations affect disk caching behavior. Further, the relative sizes of the main memory at each server (with regard to disk space usage) and the number of servers participating in the parallel query processing also affect imbalance of local query execution times. These are relevant findings that have not been reported before and that, we understand, are of interest to the research community.  相似文献   
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OBJECTIVES: The United Arab Emirates is witnessing a rapid development in population and infrastructure, leading to an expansion in the educational field and the health care system, including universities, hospitals and research institutes. One potential outcome of this development is an increase in biomedical research publications. This was examined in this study. METHOD: Searches were made of three databases; PubMed, Current Contents and embase. All records from these databases related to the Emirates were downloaded and cross-referenced. Duplications were removed as well as erroneous records. A total of 1369 publications during 1998-2004 were obtained. RESULTS: Analysis of these records revealed that the Faculty of Medicine and Health Sciences, located at the federal University, was responsible for 48% of all biomedical publications. All hospitals together accounted for 24%, while other universities and other research institutes accounted for 13 and 14% respectively. Further analysis revealed that there had been no further growth in the number of publications since 1998. This is in contrast to the increasing number of institutions that have been set up in the 1998-2004 period; from 29 to 112. CONCLUSION: The Emirates are witnessing a rapid development in universities, colleges, hospitals and research centres. The ratio of publications, as yet, has not kept up with this development. The enormous growth in institutes, however, may, in time, herald an Arabian renaissance in scientific activity and related publications.  相似文献   
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