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31.
Students and parents rely on Web-based tools to navigate the college-choice process, yet little research has been done to understand this environment. While this shift has made the process easier to navigate for some, we contend that the move will grow an already large digital divide in the USA. We use Hossler and Gallagher's college-choice framework to examine the substance and function of three college-access Web portals. Our findings suggest these tools are likely to serve many students well in the process, but may exacerbate the digital divide with consequences for low-income students.  相似文献   
32.
Some research within developmental psychology shows a slow period of development in children's expressive drawings during the primary school years. Developmental researchers suggest that ‘educational factors’ could contribute to this dip in development but have not explored these factors. This study explores links between educational policy – in terms of the English National Curriculum – and the development of expression in child art. A Foucauldian style analysis of interviews is presented which investigates how ten primary school teachers working in two Staffordshire schools approach art. A specific concern is to explore how different understandings of art and teaching practices are shaped and managed by the curriculum. This allows links between the demands of the curriculum and the observed dip in expressive drawing development to be investigated.  相似文献   
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Alcohol consumption and health outcomes are complex and multidimensional. Ethanol (1.6g / kg body weight/ day) exposure initially affects liver function followed by renal function of 16–18 week-old male albino rats of Wistar strain weighing 200–220 g. Chronic ethanol ingestion increased in thiobarbituric acid reactive substances level and glutathione s-transferase activity; while decreased reduced gluatathione content and activities of catalase, glutathione peroxidase and glutathione reductase in a time dependent manner in the hemolysate. Though superoxide dismutase activity increased initially might be due to adaptive response, but decreased later. Elevation of serum nitrite level and transforming growth factor-b1 activity indicated that long-term ethanol consumption may cause hepatic fibrosis and can elicit pro-angiogenic factors. However, no alteration in vascular endothelial growth factor-C activity indicated that ethanol consumption is not associated with lymphangiogenesis. Therefore, we conclude that long-term ethanol-induced toxicity is linked to an oxidative stress, which may aggravate to fibrosis and elevate pro-angiogenic factors, but not associated with lymphangiogenesis.  相似文献   
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Non-alcoholic fatty liver disease and its more aggressive form, non-alcoholic steatohepatitis are entities that are becoming more and more interesting to the medical community in general. A total of 93 Non-alcoholic fatty liver disease patients (64 male and 29 female) within the age range between 28 to 63 years were studied. All of them showed elevated alanine aminotransferase level (104.07 ± 56.04). Aspartate aminotransferase level (58.13 ± 31.96) was elevated more than its normal level in 82% cases and AST to ALT ratio was found 0.59 ± 0.26. Predisposing factors were diabetes mellitus (37%), obesity (13%) and hyperlipidemia (41%). In addition, 32% of the subjects were overweight.18% of the patients had elevated serum bilirubin. Our findings recommend a lower cutoff value than suggested by the World Health Organization for overweight and obesity among this racial-ethnic group.  相似文献   
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Forty-five Grade 3 students from a reservation school in Western Canada were divided into two remedial groups and a no-risk control group. One remedial group was given a classroom-administered cognitive enhancement program (COGENT) throughout the school year. The second group received COGENT for the first half of the year followed by a pull-out cognitive-based reading enhancement program (PREP). Children were assessed across phonological awareness, rapid naming, reading, and cognitive ability at the beginning of the year, mid-term, and at the end of the school year. MANOVA results showed a significant interaction for reading measures, with students receiving classroom intervention over the school year making the greatest gains. Results are discussed in terms of group, remediation program, and individual participant improvements.  相似文献   
39.
Polyunsaturated fatty acids (PUFAs) possess anti-cancer action both in vitro and in vivo. In the present study, we detected cell viability with methyl thiazolyl tetrazolium (MTT) assay and cell membrane permeability with propidium iodide (PI) fluorescence dyeing, and calculated cell membrane fluidity change as fluorescence anisotropy. Fatty acid content in cells was measured by gas chromatography/mass spectroscopy (GC/MS), and the relationship between fatty acid composition and cell viability was studied. We observed that n-6 PUFA linoleic acid (LA) inhibited tumor cell growth at high concentrations (≥300 μmol/L), while low concentrations (100–200 μmol/L) seemed to promote cell proliferation. Analyses of cell membrane permeability, cell membrane fluidity, and cell fatty acid composition suggested that the anti-cancer action of LA could be related to changes in the ratio of n-6 to n-3 PUFAs. We observed that pre-incubation of cancer cells with 100 μmol/L LA for 24 h enhanced cell sensitivity to the cytotoxic action of LA, whereas undifferentiated cell line LoVo seemed to have a distinct path in LA-induced death. These results showed that one of the mechanisms by which supplementation of LA induces cancer cell death could be altering the ratio of n-6/n-3 PUFAs, and this may be related to cell differentiation status.  相似文献   
40.
Soil test crop response (STCR) correlation studies were carried out in Vindhyan alluvial plain during 2001 to 2004 taking IR-36 as test crop to quantify rice production in the context of the variability of soil properties and use of balanced fertilizers based on targeted yield concept. The soils were developed on gently sloping alluvial plain with different physiographic settings and notable variation in drainage condition. Soil properties show moderate variation in texture (loamy to clay), organic carbon content (4.4 to 9.8 g/kg), cation exchange capacity (10,2 to 22.4 cmol (p+)/kg) and pH (5.3 to 6,4), Soil fertility status for N is low to medium (224 to 348 kg/ha), P is medium to high (87 to 320 kg/ha) and K ranges from medium to high (158 to 678 kg/ha). Database regarding nutrient requirement in kg/t of grain produce (NR), the percent contribution from the soil available nutrients [CS (%)] and the percent contribution from the applied fertilizer nutrients [CF (%)] were computed for calibrating and fbrmulating fertilizer recommendations. Validity of the yield target for 7 and 8 t/ha was tested in farmers' fields and yields targets varied at less than 10%. The percent achievement of targets aimed at different level was more than 90%, indicating soil test based fertilizer recommendation approach was economically viable within the agro-ecological zone with relatively uniform cropping practices and socio-economic conditions.  相似文献   
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