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991.
African American students continue to attend college at much lower rates than their white, Asian, and Latino counterparts. Although researchers have examined this issue from a multitude of vantage points, the voices of students—particularly students of color—have been limited in this research. Using a counter-storytelling narrative approach, this study examines what urban African American high school students identify as the critical factors affecting their educational trajectory and college-going prospects. Findings from the current study reveal that students identified inadequate resources, tracking, lack of AP courses, and poor teachers as factors that influenced their high school to college transition. This study provides much needed insight into the discourse on school reform from the most important constituent in schools—the students.  相似文献   
992.
993.
994.
The oxidative modification of lipoprotein especially low density lipoprotein (LDL) plays a key role in the initiation and progression of atherosclerosis. Serum apolipoproteinB (apoB) level is found to be an important marker for atherosclerosis. The present paper focuses on the measurement of serum apoB levels and the effect of Vitamin E, Vitamin C and reduced glutathione on the copper ion induced oxidation of LDL + VLDL (VLDL-Very Low Density Lipoprotein) lipoprotein fraction isolated from the serum of chronic renal failure (CRF) and renal transplanted patients. The level of apoB is significantly higher in the serum of transplanted patients when compared to CRF patients and normal subjects. The level of TBARS formed in oxidized LDL + VLDL lipoprotein fraction of CRF and renal transplanted patients are significantly increased than normal even in the presence of antioxidants but the level of TBARS produced, with antioxidants is comparatively lesser than that produced by oxidized lipoprotein fraction without antioxidants. It may be concluded than that produced by oxidized lipoprotein fraction without antioxidants. It may be concluded that oxidation of LDL can be prevented at an earlier stage by Vitamin E supplementation. The supplementation with Glutathione serves as the best method of preventing the lipoprotein oxidation among the renal diseased patients.  相似文献   
995.
To study the protective role of Arogh on isoproterenol induced myocardial damage in rats. The effect of Arogh pretreatment on isoproterenol induced myocardial damage was assessed by studying the levels of lipid peroxides and changes in the activity of marker enzymes such as creatine kinase, lactate dehydrogenase and transaminases in serum and heart tissue. In isoproterenol administered rats, a significant decrease was observed in the activity of marker enzymes in the heart with a corresponding increase in their levels in serum. Lipid peroxide levels increased significantly in the serum and heart. In rats pretreated with arogh, the level of lipid peroxides and the activity of marker enzymes were maintained at near normal values. Pretreatment with Arogh offered a protective effect against isoproterenol induced myocardial damage in rats as evidenced by LDH isoenzyme patterm and histopathological studies of heart tissue.  相似文献   
996.
997.
Two indigenous drugsPremna latifolia Roxb (Agnimandha) andImperata arundinacea Cyril (Darbha) were studied for their anticalculogenic effect at 20 and 100 mg concentrations. Both the concentrations were found to be equally effective in reducing the size of oxalate crystal growthin vitro over a period of 30 days. There was no change in infra red spectra while scanning electron microscope analysis showed development of cracks in the interior of the crystals and a tendency for rupture of crystals. Chemolysis appears to be the mechanism of action of the drugs.  相似文献   
998.
Exact solutions, based on couple-stresses plane strain theory of elasticity, are presented for the normal, shear and couple-stresses, displacements and rotations of an infinite-length (in z-axis) rectangular thin plate simply supported at two opposite edges (i.e.xL) and bent by a uniform load. Exact solutions reduce to classical values as l→0. Here l is defined as the new elastic material constant taking account of couple stresses.  相似文献   
999.
1000.
Although the inventions embodied in the Internet originated in a diverse set of industrial economies, the US was consistently the source of critical innovations and an early adopter of new applications. Why did other nations, including several that made important inventive contributions to the Internet, not play a larger role in its development, particularly in the creation of new business organizations, governance institutions, and applications? We argue that the role of the US “national innovation system” in the creation of the Internet echoes several key themes of US technological development before 1940. The presence of a large domestic market, a set of antitrust and regulatory policies that weakened the power of incumbent telecommunications firms, and a diverse private/public research community that was willing to work with both domestic and foreign inventions were important preconditions for US leadership in computer networking innovation.  相似文献   
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