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排序方式: 共有5121条查询结果,搜索用时 15 毫秒
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In this paper, we present a series of studies performed in the last decade that examined the contribution of e-books reading to the language and literacy of young Hebrew-speaking children. Children worked with two e-books designed by the researchers to achieve this aim. We present the effect of reading these e-books on the language and literacy of young children: (a) in general, (b) in different socio-economic statues (SES) groups, (c) among children at risk for learning disabilities (ALD). Language progress was measured by phonological awareness, word meaning, story production and comprehension, and literacy progress was measured by letter naming, word reading and word writing. Results showed that the e-book reading supported all language and literacy skills, except letter naming. The progress of most skills appeared after three reading sessions. Children from middle- and low-SES families benefited from reading the e-books and in some cases, low-SES children were contributed more than those from a middle SES. ALD children improved their vocabulary, phonological awareness and concept about print when provided with an educational e-book. Further research and pedagogical implications for software developers and educators are discussed. 相似文献
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Abidov A Kaluski E Hod H Leor J Vered Z Gottlieb S Behar S Cotter G;Israel Working Group on Intensive Cardiac Care 《The American journal of cardiology》2004,93(1):76-80
Right bundle branch block and complete atrioventricular (AV) block are conduction disorders (CDs) that have been observed in 14% of patients admitted with ST-elevation acute myocardial infarction. CDs carry a poor prognosis, with a threefold increase in the mortality rate, mainly due to cardiogenic shock and recurrent fatal myocardial infarction at 1-year follow-up. According to multivariable analysis, CD was the second strongest predictor of death, after high Killip class. Compared with patients without CD, the 1-year outcome of patients with CD was identically worse, irrespective of whether CD appeared during admission, disappeared, or remained constant. Similar adverse outcomes were seen in patients with complete AV block and right bundle branch block. 相似文献
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Barash H Gross E Edrei Y Pappo O Spira G Vlodavsky I Galun E Matot I Abramovitch R 《Hepatology (Baltimore, Md.)》2008,48(4):1232-1241
Liver diseases and regeneration are associated with hemodynamic changes denoting pathological alterations. Determining and monitoring physiological and pathological liver changes is essential for diagnostic and therapeutic objectives. Our aim was to determine the feasibility of functional magnetic resonance imaging (fMRI) during hypercapnia and hyperoxia for monitoring liver pathology. Liver fMRI images were acquired in rodents following acute bleeding, partial hepatectomy, and fibrosis. Results were quantitated and confirmed by histology. Changes induced by hyperoxia and hypercapnia following hemorrhage significantly correlated with the percentage of blood loss, reflecting lower liver perfusion and diminished vessel responsiveness to gas saturation. Hepatectomy resulted in an early decline in signal intensity changes due to hyperoxia, suggesting a decrease in liver perfusion and blood content. Following hepatectomy, signal intensity changes due to hypercapnia increased, signifying a change in liver perfusion from a mainly portal to a more arterial source. Two weeks after induction of fibrosis, signal intensity changes due to hypercapnia became much lower and those due to hyperoxia were much higher than those in normal livers, reflecting the increased perfusion due to the inflammatory process as confirmed by histologic analysis. With fibrosis progression, signal intensity changes induced by hypercapnia and hyperoxia were gradually attenuated, indicating structural and functional alterations of the liver vasculature during fibrosis. CONCLUSION: In various liver pathologies, fMRI response to hypercapnia and hyperoxia is sensitive to changes in liver hemodynamic status involved in hepatic damage or recovery; thus, this technique may offer an additional noninvasive diagnostic tool for evaluation and follow-up of liver diseases by means of examining perfusion-related alterations. 相似文献
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D'Souza S Levy E Mack D Israel D Lambrette P Ghadirian P Deslandres C Morgan K Seidman EG Amre DK 《Inflammatory bowel diseases》2008,14(3):367-373
BACKGROUND: Some dietary foods are considered protective (vegetables and fruits), whereas others (fatty foods) are thought to enhance the risk for Crohn's disease (CD). The evidence, however, is inconsistent. METHODS: We postulated that specific dietary patterns may influence the risk for CD. A case-control study was carried out. Newly diagnosed CD cases with population and/or hospital-based controls < or =20 years were selected from 3 tertiary hospitals across Canada. Pre-disease diet was assessed using a validated food frequency questionnaire (FFQ) administered within 1 month of diagnosis. Factor analyses and unconditional logistic regression (adjusted) was used to determine gender-specific dietary patterns and assess associated risks for CD. Odds ratios (ORs) and corresponding 95% confidence intervals (95% CIs) were estimated. RESULTS: A total of 149 cases and 251 controls were included. The mean age (range) of the cases was 13.3 (2.6-20 years). There were more boys (61.1%). Four dietary patterns each were observed among both boys and girls. Pattern 1 in girls, characterized by meats, fatty foods, and desserts, was positively associated with CD (OR 4.7, 95% CI 1.6-14.2). Pattern 2, common to both boys and girls, was characterized by vegetables, fruits, olive oil, fish, grains, and nuts and was inversely associated with CD in both genders (girls: OR 0.3, 95% CI 0.1-0.9; boys: OR 0.2, 95% CI 0.1-0.5). CONCLUSIONS: Our results suggest that specific dietary patterns could be associated with higher or lower risks for CD in children. Larger prospective studies are required to confirm these findings. 相似文献
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In vivo fragmentation of heparan sulfate by heparanase overexpression renders mice resistant to amyloid protein A amyloidosis 下载免费PDF全文
Li JP Galvis ML Gong F Zhang X Zcharia E Metzger S Vlodavsky I Kisilevsky R Lindahl U 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(18):6473-6477
Amyloid diseases encompass >20 medical disorders that include amyloid protein A (AA) amyloidosis, Alzheimer's disease, and type 2 diabetes. A common feature of these conditions is the selective organ deposition of disease-specific fibrillar proteins, along with the sulfated glycosaminoglycan, heparan sulfate. We have generated transgenic mice that overexpress human heparanase and have tested their susceptibility to amyloid induction. Drastic shortening of heparan sulfate chains was observed in heparanase-overproducing organs, such as liver and kidney. These sites selectively escaped amyloid deposition on experimental induction of inflammation-associated AA amyloidosis, as verified by lack of material staining with Congo Red, as well as lack of associated polysaccharide, whereas the same tissues from control animals were heavily infiltrated with amyloid. By contrast, the spleens of transgenic mice that failed to significantly overexpress heparanase contained heparan sulfate chains similar in size to those of control spleen and remained susceptible to amyloid deposition. Our findings provide direct in vivo evidence that heparan sulfate is essential for the development of amyloid disease. 相似文献