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101.
Living organisms ranging from bacteria to human beings exhibit 24-h rhythms in various behaviours and physiological processes. Matching of the period of such rhythms with that of the daily environmental cycles gives an impression that they are mere passive responses to environmental changes. Here, we discuss the change in our perception about daily biological rhythms, from their identity as rhythmic phenomena occurring as passive response to environmental changes, to the biological clocks. This is the first article in a series of articles on circadian rhythms which will cover discussion on the genetic and molecular basis, circadian organization and its adaptive significance.  相似文献   
102.
The Nobel Prize in Chemistry, 2012 has been awarded to Robert J Lefkowitz and Brian K Kobilka for their studies on G-Protein Coupled Receptors (GPCRs). GPCRs are receptor proteins present on the cell surface, which are involved in sensing molecules outside the cell and initiating a cellular response. They can sense a wide variety of ligands ranging from light to hormones and small peptides, triggering various physiological responses. Today we understand the molecular mechanisms by which these receptors work largely due to the contributions of Lefkowitz and Kobilka. Owing to the role of GPCRs in cell communication and involvement in various disease conditions, they are targets of over 40% of current drugs in the market. These findings have not only revealed how GPCRs work, but have also made a huge impact on the field of GPCR-associated drug discovery.  相似文献   
103.
In light of the focus placed on English education by the colonial government, and the petition signed by 70,000 local inhabitants of the Madras Presidency, Lord John Elphinstone, the Governor, made efforts to disseminate English education during his governorship (1837–1842). Spurred on by the petition, Elphinstone wrote two fundamental educational minutes, in 1839 and 1841, and established Madras High School. Later, the School was transformed into Presidency College and became the first home of the University of Madras. Elphinstone’s planning led to the first systematic effort by the Madras government to impart English education. Subsequently, Elphinstone emphasised the dissemination of secular education and inclusion of native people in educational administration. Against this background, this paper discusses the contribution of Elphinstone to the educational development of Madras. It also questions the historiographical neglect of Elphinstone and challenges the established post-colonial discourse that the establishment of English institutions was a ‘colonialist’ imposition.  相似文献   
104.
To maintain their global positioning, some of the world's most prominent institutions are pursuing strategic transnational alliances. In this paper I examine one such transnational alliance – that between the Massachusetts Institute of Technology and the government of Singapore. Using governmentality as a framework of analysis, the paper locates the Singapore‐MIT Alliance within the broader policy architecture that underpins Singapore's knowledge economy aspirations. The Alliance demonstrates some of the practical complexities involved in ‘leap‐frogging’ into the ‘value‐added’ realms of knowledge and service‐related production. It highlights the resistances, tensions and contradictions arising from leveraging off foreign expertise to build an education hub. The paper concludes with a discussion of the changing regimes of value arising from aspiring knowledge economies.  相似文献   
105.
Both (a) in-school factors such as over-focus on academic performance, absence of uniform, and corporal punishment, and (b) out-of school factors such as caring for ailing parents, child labour, etc., hinder participation of orphan and vulnerable children (OVC) in Free Primary Education (FPE) system in Nyanza Province, Kenya. In this context Concern Worldwide Kenya undertook an appreciative capacity building approach and appropriately positioned District Education Office (DEO) of the Ministry of Education and local civil society organisations (CSOs) to address in-school and out-of-school factors, respectively, to ensure quality education for OVC. The outcome of the programme is promising and has demonstrated the need for greater cooperation between CSOs and the government to develop creative strategies in overcoming the causes of marginalisation within the contexts of the growing AIDS pandemic and poverty in Kenya.  相似文献   
106.
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   
107.
This study was conducted to find out the level of oxidative stress and effect of supplementation of vitamin C, D and Calcium on levels of SOD, serum and urinary fluoride in children residing in endemic fluorosis area. For this the fluoride belt of Jaipur district was selected. The parameters selected were Super oxide dismutase, serum fluoride and urinary fluoride. The study was conducted on one hundred children, selected from four areas (25 from each area) consuming water containing 1.2, 2.4, 5.6 and 13.6 mg/l of fluoride. Drinking water fluoride, serum and urinary fluoride were measured by Ion selective electrode method. Serum SOD by Xanthine oxidase method using kit of Ransod (kit cat. No. SD125). The post treatment values showed a significant reduction in serum fluoride and SOD. Urinary fluoride levels increased significantly in post treatment stage. The results revealed a normal SOD levels in all groups but an increasing trend was observed with increasing fluoride concentration. Treatment with Calcium, Vitamin D and Vitamin C showed a significant reduction in serum fluoride and SOD and increase in urinary fluoride. A high positive correlation between pretreatment and post treatment group was observed in serum fluoride, SOD and urinary fluoride (P < 0.05). The study indicated an increasing oxidative stress in cases of fluorosis with increasing drinking water fluoride concentration. Treatment with Calcium, Vitamin D and Vitamin C resulted a significant reduction in serum fluoride and SOD and increase in urinary fluoride.  相似文献   
108.
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   
109.
110.
We have developed a biostrip for determination of urea in serum. The test strip is based on enzymatic assay where urease has been immobilized on the chromatographic paper along with chromogen, phenol red. The chromogen is easily soluble in water and does not require other components for the color change. Serum urea reacts with urease and water to liberate ammonia and carbon dioxide. The liberated ammonia changes the pH of the reaction medium, which is monitored by the chromogen phenol red. A single step working reagent strip has been developed and the reaction is completed within 50 seconds at room temperature. With this test strip urea concentration is measured in serum as low as 0.15 g/L. The speed and convenience of determining urea in serum by this strip instantly makes it well suited for individuals, physicians and emergency centres.  相似文献   
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