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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
981.
Statistical and Fourier analysis methods of time series representing fluctuations of stock market in general and Indian stock markets in particular are well known. This work is motivated by a recent paper by Guharay [Operations Research and Financial Engineering, Princeton University, Princeton, NJ, preprint, 2002] where he has studied trends in the S & P 500 for various time periods using wavelet tools. Our paper deals with a few Indian and Saudi stock prices and return fluctuation for a certain period of time. The main objective of the analysis is to understand the dynamics of the Indian and Saudi stock markets. We look for similarities, point of abrupt changes, normalized data, return, volatility, graph, pure and noise part, correlation lengths, and signal-to-noise ratio. 相似文献
982.
R Abraham M Joseph John R Calton J Dhanoa 《Indian journal of clinical biochemistry : IJCB》2006,21(1):95-100
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
983.
Lakshmi Lavanya Reddy Swarup A. V. Shah Alpa J. Dherai Chandrashekhar K. Ponde Tester F. Ashavaid 《Indian journal of clinical biochemistry : IJCB》2016,31(1):87-92
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
984.
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
985.
Chandrawati Kumari Bijo Varughese Siddarth Ramji Seema Kapoor 《Indian journal of clinical biochemistry : IJCB》2016,31(4):414-422
Pre analytical process of extraction for accurate detection of organic acids is a crucial step in diagnosis of organic acidemias by GCMS analysis. This process is accomplished either by solid phase extraction (SPE) or by liquid–liquid extraction (LLE). Both extraction procedures are used in different metabolic laboratories all over the world. In this study we compared these two extraction procedures in respect of precision, accuracy, percent recovery of metabolites, number of metabolites isolated, time and cost in a resource constraint setup. We observed that the mean recovery from SPE was 84.1 % and by LLE it was 77.4 % (p value <0.05). Moreover, the average number of metabolites isolated by SPE and LLE was 161.8 ± 18.6 and 140.1 ± 20.4 respectively. The processing cost of LLE was economical. In a cost constraint setting using LLE may be the practical option if used for organic acid analysis. 相似文献
986.
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
987.
Winston Costa Pereira Muddanna S. Rao D. M. Vasudevan 《Indian journal of clinical biochemistry : IJCB》2003,18(2):161-168
Immunization with a proper dose of an antigenic stimulus leads to cell proliferation and antibody response of circulating
lymphocytes. We have previously observed that Secondary immunized spleenocytes resist ceramide-mediated apoptosisin vitro. Our present study is aimed at investigating thein vivo effect of immunization on apoptosis. Mice were subjected to either Primary or Secondary dose with Tetanus Toxoid. Unimmunized
spleenocytes served as controls. Unimmunized, Primary and Secondary immunized mice were later exposed to chemotherapeutic
drugs such as Etoposide/Methotrexate/Vincristine to induce apoptosis. Apoptosis was studied by using the Feulgen reaction
on 5μ thin parafin sections of spleen. It was observed that Secondary immunized mice showed a lower percentage of apoptosis
as compared to Primary or Unimmunized mice that was subjected to either of the chemotherapeutic drugs. It was thus concluded
that Secondary immunization inhibits the process of chemotherapeutic drug induced apoptosis in vivo. 相似文献
988.
Sameer Hinduja 《Ethics and Information Technology》2007,9(3):187-204
Accompanying the explosive growth of information technology is the increasing frequency of antisocial and criminal behavior
on the Internet. Online software piracy is one such behavior, and this study approaches the phenomenon through the theoretical
framework of neutralization theory. The suitability and applicability of nine techniques of neutralization in determining
the act is tested via logistic regression analyses on cross-sectional data collected from a sample of university students
in the United States. Generally speaking, neutralization was found to be weakly related to experience with online software
piracy; other elements which appear more salient are suggested and discussed in conclusion. 相似文献
989.
990.