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991.
A. Bhise P. V. Krishnan R. Aggarwal M. Gaiha J. Bhattacharjee 《Indian journal of clinical biochemistry : IJCB》2005,20(2):4-9
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
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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
994.
Are preservice teachers prepared to teach struggling readers? 总被引:1,自引:0,他引:1
Reading disabilities such as dyslexia, a specific learning disability that affects an individual’s ability to process written
language, are estimated to affect 15–20% of the general population. Consequently, elementary school teachers encounter students
who struggle with inaccurate or slow reading, poor spelling, poor writing, and other language processing difficulties. However,
recent evidence may suggest that teacher preparation programs are not providing preservice teachers with information about
basic language constructs and other components related to scientifically based reading instruction. As a consequence preservice
teachers have not exhibited explicit knowledge of such concepts in previous studies. Few studies have sought to assess preservice
teachers’ knowledge about dyslexia in conjunction with knowledge of basic language concepts. The purpose of the present study
was to examine elementary school preservice teachers’ knowledge of basic language constructs and their perceptions and knowledge
about dyslexia. Findings from the present study suggest that preservice teachers, on average, are able to display implicit
skills related to certain basic language constructs (i.e., syllable counting), but fail to demonstrate explicit knowledge
of others (i.e., phonics principles). Also, preservice teachers seem to hold the common misconception that dyslexia is a visual
perception deficit rather than a problem with phonological processing. Implications for future research as well as teacher
preparation are discussed. 相似文献
995.
This article reports on a collective self-study from our multiple and unique experiences of teaching self-study research in the Netherlands and the United States. Through the methodology of dialog, we merged what we learned from our individual studies which resulted in six guidelines for a pedagogy for teaching self-study research. Without claiming that the six guidelines have full applicability to all teaching contexts, we offer instead a discussion of the complexities and value of framing a pedagogy of self-study research. This study provides a conceptual, theoretical, and practical base for further studies to build a knowledge base on this topic. 相似文献
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There are two indisputable findings in science education research. First, students go to school with some intuitive beliefs
about the natural world and physical phenomena that pose an obstacle to the learning of formal science. Second, these beliefs
result from the confluence of two factors, namely, their everyday experience as they interact with the world around them and
a set of operational constraints or principles that channel both perceptually and conceptually the way these experiences are
perceived and interpreted. History of science suggests that the theories of early scientists through which they sought to
explain physical phenomena relied mostly on ideas that closely fitted their experiences of the relevant phenomena. This characteristic
of the early scientific ideas is the root of the epistemological difficulties that early scientists faced in their attempts
to explain the phenomena. In this paper, we focus on the early theories in optics (from ancient Greek to the late Islamic
scientific traditions) and argue that students face some of the same epistemological problems as early scientists in explaining
vision and optical phenomena for the reason that students’ intuitive beliefs are also closely tied to particular phenomena
and as a result the underlying notions are fragmentary and lack the necessary generality that would allow them to cover many
disparate phenomena. Knowledge of these epistemological problems can help the instructor to identify the key elements for
a better understanding of the formal theory of optics and, in turn, lead to a more effective instruction. 相似文献