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941.
Images of Newton     
Fara P 《Endeavour》2000,24(2):51-52
  相似文献   
942.
The present study was undertaken in 100 subjects, 30 diabetics without complication (group I), 40 diabetics with retinopathy (group II) and 30 non diabetic as normal control group (group III). Blood sugar levels, magnesium, cholesterol and triglyceride were analyzed from plasma and serum. The results were correlated with degree of diabetic control from the levels of glycosylated hemoglobin. Serum magnesium levels in group II were found to be significantly lowered than in group I. There was also significant difference in magnesium levels of group I and group III. We found a significant correlation between the glycosylated hemoglobin and magnesium levels in our study. The results also indicate that the patients with diabetic retinopathy showed significant rise in serum cholesterol and triglyceride. Probably hypomagnesemia and increased serum cholesterol and triglyceride levels are responsible for microvascular changes in diabetes leading to retinopathy. The purpose of this study was thus to gather information about the degree of control of diabetes and magnesium status.  相似文献   
943.
The ubiquitous fungus Aspergillus fumigatus causes allergic rhinitis, asthma, sinusitis and allergic bronchopulmonary aspergillosis. A number of major allergens from A. fumigatus are purified, but their structure-function role in the pathogenesis of disease is not known. Such information is essential for devising alternative therapy of fungal allergic diseases. In the present study, N-terminal and C-terminal deletion mutants ofAsp f 3 were constructed and their immunopathological responses studied in a mice model of allergy. Three mutants viz,Asp f 3 (aa 33–168), (aa 1–142), and (aa 23–142) were made by deleting certain amino acids from epitopic regions of full lengthAsp f 3, a major allergen of A. furnigatus. TheAsp f 3 and three mutated proteins were expressed in pET vector. The C-terminal deletion mutantAsp f 3 (aa 1–142) induced elevated IFN-γ but low levels of IL-4 by spleen cells. This mutant also showed significant downregulation of peripheral blood eosinophils and lung inflammation in immunized mice. The N-terminal deletion mutantAsp f 3 (aa 33–168) also exhibited an immuno-suppressive effect in terms of IgE production and induction of Th2 cytokine. The results indicate thatrAsp f 3 and its deletion mutants induced distinct immune-inflammatory responses in mice on challenge with these proteins. The non-IgE binding deletion mutants ofAsp f 3 (aa 1–142 and aa 33–168) could deviate Th2 immune response with a concomitant reduction in airway inflammation and infiltration of inflammatory cells.  相似文献   
944.
From January 1992-January 1998, 1404 patients attended the “Breast Clinic” of R.N.T. Medical College M.B. Hospital, Udaipur. Out of these, 11% and 81% patients had breast cancer (B.C.) and benign breast cancer (B.B.D.) respectively. The oxidative load in B.C. was 2.32 times higher than controls, but comparable to B.B.D. β-Carotene deficiency was uncommon in patients, whereas vitamin A deficiency was almost equally common in both B.C. and controls. Most of the patients had almost depleted levels of α-tocopherol and ascorbic acid but their TBAR levels were in normal range. The data in the present study when compared with B.B.D. and other local normal subjects point out: a) oxidative burden in B.C. is a consequence and not the cause of the disease, (b) oxidative stress could be one of the etiological factors in tumor expression, which need not to be malignant and c) α-tocopherol and ascorbic acid are not importantly responsible for higher oxidative burden in B.C.  相似文献   
945.
This paper investigates the role of government R&D subsidy programs in stimulating knowledge spillovers. R&D subsidies are an effective public policy instrument when knowledge spillovers exist yet ex ante it is difficult to identify projects that have the greatest potential to increase innovation and economic growth. This paper derives a set of project and firm attributes that the literature finds generate knowledge spillovers and uses data on project proposals to estimate the degree to which a government R&D program conforms. We find that projects that were awarded R&D subsidies were more likely to have attributes such as participation in new research joint ventures and connections to universities and other firms. Following the post-award activities of firm, we find that receipt of a government R&D subsidy increased the funding from other sources when compared to firms that were not awarded funding.  相似文献   
946.
947.
The present study comprised 100 patients of essential hypertension who were screened for fasting hyperinsulinemia, which was detected in 77% cases. Twenty such hyperinsulinemic cases were subjected to 4 weeks of dietary control phase followed by 6 weeks of omega-3 fatty acids substitution [either 0.6 g/d (group 1) or 1.2 g/d (group 2)]. The mean basal fasting plasma insulin levels were significantly higher (p<0.001) in patients of hypertension when compared to normal controls (126.51±80.36 and 19.35±12.61 μU/ml respectively). At the end of 4 weeks of diet control only, no significant change was observed in any parameter. After substitution of omega-3 fatty acid, a significant reduction of fasting plasma insulin levels in both group 1 (29%) and group 2 (22.8%) was observed (p<0.001). Significant reduction of systolic and diastolic blood pressure (16.4% and 25% respectively), serum cholesterol, triglycerides and low density lipoprotein was also noted in both groups (p<0.001), while high density lipoprotein increased by ∼8 mg% in both groups. Thus omega-3 fatty acid substituion in low dose along-with curtailment of dietary omega-6 fatty acid may be used as an adjunctive measure in the management of essential hypertension.  相似文献   
948.
949.
950.
In previous work it was established that the U.K. tractor industry was characterised by a high degree of technical change and that this was brought about by a process of more or less continuous incremental innovation. What was lacking was an analysis of how much technical change had been introduced and an indication of the role played by technical change in determining the performance of the U.K. tractor industry internationally. This paper concludes that on the average technical change in the industry had increased by as much as 150 percent during the years 1959–1977, though there is some indication that the rate of change might now be slowing somewhat.In order to determine the relative importance of technical change a method was developed to operationalise the distinction between price and non-price competition as well as the idea of intrinsic (technical) and associative (non-technical) factors as constituents of the latter. Based on cross-sectional data for the year 1978, it has been possible to show that British manufacturers tend to produce moderately priced tractors of low to medium technical sophistication: that German manufacturers produced the most technically sophisticated tractors; that the Italian manufacturers are not generally more sophisticated, technically, than the British producers except with respect to their development of four-wheel drive; and that COMECON-based producers combine a very low price with some degree of technical sophistication. Finally, it has been possible to show that the tractors with the highest sales are among the less sophisticated in each of the power ranges investigated and that new entrants used technical sophistication as an element of their entry strategy. The answer to the question of what allows the market leader to be market leader required the development of measures for associative non-price factors, such as the availability of a dealer network brand loyalty, resale prices of tractor models, etc. By performing a regression analysis on these measures along with previously derived measures of quality-adjusted price and relative technical sophistication it has been possible to show that market leadership is achieved as a result of a balance of a number of factors, the most important of which are the size of the dealer network, warrants cost, advertising, technical sophistication and price.  相似文献   
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