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排序方式: 共有98条查询结果,搜索用时 15 毫秒
1.
Platelets play a vital role in the progression of atherosclerosis and thrombosis, a major cause of death worldwide. Platelets are activated by many triggers like elevated LDL in blood resulting in aggregation and formation of plaque. The purpose of this study was to investigate the effect of LDL and signal transduction inhibitor on the activation of platelets in Ischaemic risk subjects. Platelets from IHD and hyperlipidemic subjects were hypersensitive to ADP, as higher levels of platelet aggregation were observed in these groups. LDL from IHD hyperlipidemic subjects was more effective in activating platelets from any other group. Ox-LDL was more effective in activating platelets than native-LDL as monitored by level of platelet aggregation induced by PAF and thrombin. Calcium channel blocker, nifedipine and verapamil inhibited platelet aggregation at micromolar level. Protein kinase inhibitor, staurosporine was effective in inhibiting ADP induced aggregation at nanomolar level.  相似文献   
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Gödel’s proof     
In 1931, the great Austrian mathematician Kurt Gödel proved “all consistent axiomatic formulations of number theory include undecidable propositions”. This discovery of Gödel and its proof had enormous repercussions in mathematics and computer science. The proof hinged upon the writing of a self-referential mathematical statement, in the same way as the liar’s paradox — I am lying — is a self-referential statement. In this three-part article, we describe Gödel’s discovery and his famous proof.  相似文献   
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The present study was conducted to investigate the oxidant–antioxidant status in iron deficient pregnant anemic women. One hundred thirty pregnant women with iron deficiency anemia (IDA) were divided into three groups, namely mild (50), moderate (50) and severe (30) anemic along with pregnant healthy women as controls (50). The complete blood count, plasma lipid peroxidation products, enzymatic and non-enzymatic antioxidants were measured according to respective protocols. The levels of complete blood count, iron, ferritin along with antioxidant enzymes namely catalase, superoxide dismutase, glutathione peroxidase, glutathione reductase and reduced glutathione were significantly reduced in all IDA groups. However, the level of oxidized glutathione, lipid peroxides, protein carbonyls, conjugated dienes were found significantly increased in all anemic patients. Antioxidant vitamins, namely C, E and A were also found significantly decreased in IDA patients. On the basis of our results, it may be concluded that IDA tends to increase the pro-oxidant components, which may result in various complications including peroxidation of vital body molecules resulting in increased risk for pregnant women as well as fetus.  相似文献   
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Cultural Studies of Science Education - The M(East) ward of Mumbai is home to one of Asia’s largest open landfill sites. Waste, therefore, is a source of livelihood for millions of people...  相似文献   
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University Technical Colleges (UTCs) are newly established (since 2010–11) technical and vocational secondary schools in England, catering for young people aged 14–19. The schools focus strongly on delivering vocational, alongside Science, Technology, Engineering and Mathematics (STEM)-focused academic, qualifications. The colleges have been introduced as a new means of improving technical and vocational education and training—a sector which in England has faced problems of low quality and low esteem—and in a wider international context of STEM-trained worker shortages. University Technical Colleges have been advertised as offering state-of-the-art vocational learning, involving access for students to the latest equipment and technologies in key industrial sectors, alongside extensive project-based learning in partnership with employers. However, how have UTC students fared in these respects since the beginning of the coronavirus pandemic and associated lockdowns in 2020? In this paper we report on results from a survey of 252 students across two UTCs in England, exploring the technical and vocational learning experiences of these students during the exceptional 2019–20 academic year. Findings from the survey reveal lost learning and training opportunities during the pandemic, particularly where courses with practical elements relied on specific equipment and facilities that became inaccessible during lockdown. The survey also highlights disruptions to apprenticeship arrangements, work experience plans and other engagement with employers. Students in some instances have been effectively forced to stay on in education owing to reduced apprenticeship and employment opportunities for school-leavers. We find evidence of students adapting their aspirations and career goals to the new economic circumstances.  相似文献   
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Clonorchis sinensis or the Chinese liver fluke is one of the most prevalent parasites affecting a major population in the oriental countries. The parasite lacks lipid generating mechanisms but is exposed to fatty acid rich bile in the liver. A secretory phospholipase A2, an enzyme that breaks down complex lipids, is important for the growth of the parasite. The enzyme is also implicated in the pathogenesis leading up to the hepatic fibrosis and its complications including cancer. The five isoforms of this particular enzyme from the parasite therefore qualify as potential drug targets. In this study, a detailed structural and ligand binding analysis of the isoforms has been done by modeling. The overall three dimensional structures of the isoforms are well conserved with three helices and a β-wing stabilized by four disulfide bonds. There are characteristic differences at the calcium binding loop, hydrophobic channel and the C-terminal domain that can potentially be exploited for drug binding. But the most significant feature pertains to the catalytic site where the isoforms exhibit three variations of either a histidine-aspartate-tyrosine or histidine-glutamate-tyrosine or histidine-aspartate-phenylalanine. Molecular docking studies show that isoform specific residues and their conformations in the substrate binding hydrophobic channel make unique interactions with certain inhibitor molecules resulting in a perfect tight fit. The proposed ligand molecules have a predicted affinity in micro-molar to nano-molar range. Interestingly, few of the ligand binding interaction patterns is in accordance to the phylogenetic studies to thereby establish the usefulness of evolutionary mechanisms in aiding ligand design. The molecular diversity of the parasitic PLA2 described in this study provides a platform for personalized medicine in the therapeutics of clonorchiasis.

Electronic supplementary material

The online version of this article (doi:10.1007/s12291-013-0377-1) contains supplementary material, which is available to authorized users.  相似文献   
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Numerous classical genetic studies have proved that genes are contributory factors for obesity. Genes are directly responsible for obesity associated disorders such as Bardet–Biedl and Prader–Willi syndromes. However, both genes as well as environment are associated with obesity in the general population. Genetic epidemiological approaches, particularly genome-wide association studies, have unraveled many genes which play important roles in human obesity. Elucidation of their biological functions can be very useful for understanding pathobiology of obesity. In the near future, further exploration of obesity genetics may help to develop useful diagnostic and predictive tests for obesity treatment.  相似文献   
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