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We aimed to assess whether measuring carotid intima-media thickness (CIMT) and oxidative stress markers such as protein carbonyls, malondialdehyde, nitrate and glutathione in plasma of elderly patients without and with coronary artery disease (CAD) identifies early risk for CAD. A total of 50 cases with cardiovascular risk factors over the age of 60 years without CAD, and 50 patients with angiographically documented CAD over the age of 60 years were included in the study. Control group consists of 200 healthy individuals without the risk factors. Demographic details were obtained from all the subjects and CIMT measured by high frequency ultrasound and oxidative stress markers such protein carbonyls, malondialdehyde and total glutathione were determined in plasma by spectrophotometric methods. The distribution of cardiovascular risk factors in without CAD and CAD cases were smokers (16 vs 56 %), hypertension (26 vs 64 %), diabetes (16 vs 56 %) and dyslipidemia (18 vs 58 %) and positive family history (4 vs 38 %). None of the control group had any cardiovascular risk factors. Among the CAD cases, 16 % had single vessel disease, 44 % had double vessel disease and 40 % had triple vessel disease. The CIMT was significantly increased in CAD cases as compared to cases without CAD and healthy controls. On the other hand, CIMT was significantly increased in cases without CAD as compared to healthy controls. CIMT also increased with the duration of diabetes in patients without CAD and severity of disease in CAD cases. The levels of oxidants like plasma malondialdehyde, protein carbonyls, were significantly elevated and antioxidant glutathione levels and nitrate levels were significantly reduced in cases with and without CAD as compared to healthy controls. Oxidative stress markers and CIMT was found to be significantly increased in patients with cardiovascular risk factors like diabetes, family history of CAD, dyslipidemia, hypertension and smoking when compared to patients without risk factors. In patients with diabetes, CIMT increased as duration of disease increases and also in poorly controlled diabetes. In CAD group, when number of vessel involvement (severity of coronary disease) increases, the CIMT also increases confirming that CIMT is a quantifiable risk factor for CAD.  相似文献   
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25-hydroxy vitamin D [25(OH) vit D] deficiency is a serious public health problem, particularly in the Indian sub-continent. The objective of the present study was to study the prevalence of 25(OH) vit D in different age groups. The data of 25(OH) vit D assay of 26,346 ostensibly healthy individuals, enrolled under executive health checkup at Medanta The Medicity, Gurgaon, over a period of 3 years, were extracted from the hospital information system and reviewed extensively. 25(OH) vit D deficiency (VDD) was defined as 25(OH) vit D < 20 ng/ml, insufficiency (VDI) as 25(OH) vit D between 20 and 40 ng/ml and 25(OH) vit D sufficiency (VDS) as 25(OH) D > 40 ng/mL. 25(OH) vit D deficiency (VDD + VDI) was observed in 93 % of the subject population. Maximum number of the subjects belonged to the age group of 41–60 years. 59 % had frank 25(OH) vit D deficiency when cut off level was <20 ng/mL. Mean value of 25(OH) vit D in our subjects was 21.4 ± 14.4 ng/mL. Significant difference in 25(OH) vit D level was observed in between male and female subjects. Simultaneously 25(OH) vit D levels were significantly lower in the patient visited hospital in winter-spring season than the summer-autumn season (p > 0.001). Our study demonstrates a high prevalence of 25(OH) vit D deficiency in an ostensibly healthy Indian population. There is a need for redefining our reference ranges according to our population and extensively improving the status of vitamin D.  相似文献   
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The burden of disease in patients with congestive heart failure is high. The future of BNP looks promising as it may be a better diagnostic tool for the diagnosis of CHF in developing countries in new millennium. Natriuretic peptide hormones, a family of vasoactive peptides with many favourable physiological properties, have emerged as important contenders for development of diagnostic tools and therapeutic agents in cardiovascular disease. Measurement of B-type natriuretic peptide has become as an easy-to-perform bedside test. The clinical and diagnostic significance of the measurement of plasma Nt-proBNP in the diseases of the cardiovascular system with particular emphasis on the assessment of patients with heart failure and their effects on predicting survival rate. The plasma levels of Nt-proBrain Natriuretic peptide responds more vigorously after myocardial infarction than those of other natriuretic peptides. This article is an attempt to give a short overview on the utility of BNP-blood levels for the diagnosis and treatment of heart failure  相似文献   
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Education and Information Technologies - Web recommendation systems are ubiquitous in the world used to overcome the product overload on e-commerce websites. Among various filtering algorithms,...  相似文献   
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Over the series of articles on circadian rhythms, we saw that living organisms exhibit daily rhythms in multiple behaviours and physiological processes. Although some rhythms may be passive responses to 24 h environmental cycles, many are regulated by endogenous-rhythmgenerating machinery called circadian clocks. We have introduced the concept of circadian clocks, their organization and the underlying molecular mechanisms. In this article, we will dwell upon one of the most fundamental questions pertaining to circadian clocks, ‘Why do we have them?’. The aim of this article is not to provide answers, but to discuss the efforts and strategies used to address this question and critically evaluate explanations proposed till date.  相似文献   
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This article illustrates the application of a pairwise comparison methodology to the doctoral program selection process. The first section includes a brief discussion of the pairwise comparison methodology better known in the literature as Saaty's Analytic Hierarchy Process. In the next section, a hierarchy for structuring and facilitating the doctoral program selection decision is described. This section is followed by an illustration of the methodology using the hierarchy for which four MBA students contemplating a doctoral program provided pairwise comparisons. Next, the results obtained above are discussed, and followed by our summary and conclusions.  相似文献   
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Fluctuation theorems are a group of exact relations that remain valid irrespective of how far the system has been driven away from equilibrium. Other than having practical applications, like determination of equilibrium free energy change from nonequilibrium processes, they help in our understanding of the second law and the emergence of irreversibility from time-reversible equations of motion at microscopic level. A vast number of such theorems have been proposed in literature, ranging from Hamiltonian to stochastic systems, from systems in steady state to those in transient regime, and for both open and closed quantum systems. In this article, we discuss about a few such relations, when the system evolves under Hamiltonian dynamics.  相似文献   
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