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61.
Mohamed F. Abdel-Megeed Mohamed A. Saleh Youssef L. Aly Ibrahim M. Abdo 《Nucleosides, nucleotides & nucleic acids》2013,32(9-10):1985-1996
Abstract A series of some new acetylated S-glycosides of 2-thioxoquinazolin-4-ones, their thiono analogues and 3,1-benzothazin-2,4-dithione derivatives, including a D-glucose and a D-galactose derivatives and a D-xylose, and an L-arabinose derivatives have been synthesized. The conformation and configuration of these carbohydrate derivatives were determined by analysing their 1H and 13C NMR chemical shifts and coupling constants. The biological activity of these compounds has been studied. 相似文献
62.
Abdel Kader Mansour Yehia A. Ibrahim Nasser S. A. M. Khalil 《Nucleosides, nucleotides & nucleic acids》2013,32(10):2265-2283
Abstract The 6-β-arylvinyl-2- and 4-glucosyl-3-thioxo-2,3-dihydro-1,2,4-triazin-5(4H)-ones were synthesized with high selectivity using the recently developed amino protecting group strategy. The structure of these new glucosides was established chemically and spectroscopically. Also, some interesting chemical transformations and rearrangements were observed. 相似文献
63.
The aim of the present study was to characterize the enzymatic deinking of various types of waste paper. Studies on the optimization of enzymatic deinking have been performed previously using commercially available enzyme preparations containing cellulase and hemicellulase. The enzymatic deinking of different types of waste paper demonstrated a high efficiency of 86.6% on laser-printed paper, but a low deinking efficiency of 12.9% was obtained with newspaper. All enzymatic treatments significantly improved the drainage rate of the deinked waste paper. Enzymatic deinking increased the tensile index of magazine paper but reduced the tensile index of bubble jet-printed paper, photocopy paper and newspaper. Enzymatic hydrolysis caused a 21.1% reduction in the tear index for bubble jet-printed paper, but a 3.1% increase in the tear index was obtained for laser-printed paper relative to respective blank. In addition, enzymatic hydrolysis increased the burst index by 4.7% relative to blank for laser-printed paper. However, photocopy paper showed the highest reduction (8.3%) in the burst index relative to blank. Taken together, these results suggest that enzymatic hydrolysis is both advantageous and detrimental to the mechanical properties of deinked paper. Thus, the proper regulation of enzymatic hydrolysis is crucial to improve the quality of recycled paper. 相似文献
64.
Over many years of his life, the British naturalist Alfred Russel Wallace (1823–1913) explored the tropical forests of Malaysia, collecting numerous specimens, including hundreds of birds, many of them new to science. Subsequently, Wallace published a series of papers on systematic ornithology, and discovered a new species on top of a volcano on Ternate, where he wrote, in 1858, his famous essay on natural selection. Based on this hands-on experience, and an analysis of an Archaeopteryx fossil, Wallace suggested that birds may have descended from dinosaurian ancestors. Here, we describe the “dinosaur-bird hypothesis” that originated with the work of Thomas H. Huxley (1825–1895). We present the strong evidence linking theropod dinosaurs to birds, and briefly outline the long and ongoing controversy around this concept. Dinosaurs preserving plumage, nesting sites and trace fossils provide overwhelming evidence for the dinosaurian origin of birds. Based on these recent findings of paleontological research, we conclude that extant birds indeed descended, with some modifications, from small, Mesozoic theropod dinosaurs. In the light of Wallace’s view of bird origins, we critically evaluate recent opposing views to this idea, including Ernst Mayr’s (1904–2005) arguments against the “dinosaur-bird hypothesis”, and document that this famous ornithologist was not correct in his assessment of this important aspect of vertebrate evolution. 相似文献
65.
Lisa Kolden Midtb? Mohammad Madani Ibrahim Lene Secher Myrmel Ulrike Liisberg Aune Anita R?yneberg Alvheim Nina S. Liland Bente E. Torstensen Grethe Rosenlund Bj?rn Liaset Trond Brattelid Karsten Kristiansen Lise Madsen 《PloS one》2013,8(1)
Background
To ensure sustainable aquaculture, fish derived raw materials are replaced by vegetable ingredients. Fatty acid composition and contaminant status of farmed Atlantic salmon (Salmo salar L.) are affected by the use of plant ingredients and a spillover effect on consumers is thus expected. Here we aimed to compare the effects of intake of Atlantic salmon fed fish oil (FO) with intake of Atlantic salmon fed a high proportion of vegetable oils (VOs) on development of insulin resistance and obesity in mice.Methodology/principal findings
Atlantic salmon were fed diets where FO was partly (80%) replaced with three different VOs; rapeseed oil (RO), olive oil (OO) or soy bean oil (SO). Fillets from Atlantic salmon were subsequently used to prepare Western diets (WD) for a mouse feeding trial. Partial replacement of FO with VOs reduced the levels of polychlorinated biphenyls (PCB) and dichloro-diphenyl-tricloroethanes (DDT) with more than 50% in salmon fillets, in WDs containing the fillets, and in white adipose tissue from mice consuming the WDs. Replacement with VOs, SO in particular, lowered the n−3 polyunsaturated fatty acid (PUFA) content and increased n−6 PUFA levels in the salmon fillets, in the prepared WDs, and in red blood cells collected from mice consuming the WDs. Replacing FO with VO did not influence obesity development in the mice, but replacement of FO with RO improved glucose tolerance. Compared with WD-FO fed mice, feeding mice WD-SO containing lower PCB and DDT levels but high levels of linoleic acid (LA), exaggerated insulin resistance and increased accumulation of fat in the liver.Conclusion/Significance
Replacement of FO with VOs in aqua feed for farmed salmon had markedly different spillover effects on metabolism in mice. Our results suggest that the content of LA in VOs may be a matter of concern that warrants further investigation. 相似文献66.
Tayel Safaa I. Alhanafy Alshimaa M. Ahmed Solwan M. Eltorgoman Abdelmoneim A. Elsayed Ibrahim E. 《Molecular biology reports》2020,47(5):3807-3820
Molecular Biology Reports - The leptin is discharged from breast adipose tissue and is overexpressed in breast cancer (BC). Conflicting relation of leptin with BC was reported. We investigated this... 相似文献
67.
Buba Ibrahim Ahmed Aliya Abubakar Sani Yusuf Ringim Namwa Voncir 《Archives Of Phytopathology And Plant Protection》2013,46(7):650-658
Abstract Field experiments were carried out at the Teaching and Research Farm of the Abubakar Tafawa Balewa University, Bauchi during the rainy season of 2005. The study was carried out with sole objective of evaluating the efficacy of six selected plant materials (sweetsop, red pepper, garlic, neem, mahogany and gmalina) against the major insect pests of cowpea variety, Dan Sokoto. The experiment was laid down in randomised complete block design with seven treatments. Each treatment was replicated three times. The results of the study showed that all the plant materials used were significantly (p < 0.05) better than control where no plant material was used in controlling the population of B. tabaci, E. dolichi, M. sjostedti and C. tomentosicollis at 1, 2 and 3 days after application of the treatments. Similarly the effects of these plant materials on the number of seeds/pod showed a significant (p < 0.05) difference between plots treated with plant materials and control. On the grain yield of the crop, all the plant materials showed significant effect except mahogany and the control which were statistically similar. Furthermore, the order of level of control indicated that sweet sop has (70.7%), garlic (69.3%), neem (61.0%), red pepper (54.0%), ash (30.9%), and mahogany (3.5%). The result of the present finding therefore recommends the use of sweet sop, garlic and neem as they were found to be the most promising in the control of major cowpea insect pests. 相似文献
68.
Nabil Khattab Ron Johnston Tariq Modood Ibrahim Sirkeci 《Ethnic and racial studies》2013,36(9):1466-1481
This paper expands the existing literature on ethnicity and economic activity in Britain by studying the impact of religion and class. It argues that while the class location of the different South-Asian groups is important in determining their labour market outcomes, it does not operate independently from ethnicity; rather it is highly influenced by ethnicity in the process of determining the labour market participation of these groups. We use data obtained from the 2001 UK Census on Indian, Pakistani, and Bangladeshi men and women aged between twenty and twenty nine. Our findings confirm that class structure of the South-Asian groups is highly ethnicized, in that the ethno-religious background and class are interwoven to the extent that the separation between them is not easy, if not impossible. 相似文献
69.
Ibrahim Guner Duygu D. Uzun Muhittin O. Yaman Habibe Genc Remisa Gelisgen Gulcan G. Korkmaz Metin Hallac Nermin Yelmen Gulderen Sahin Yesari Karter Gonul Simsek 《Biological trace element research》2013,154(2):262-267
Intermittent hypoxia is the most common pattern of hypoxic exposure in humans. The effect of chronic long-term intermittent hypobaric hypoxia (CLTIHH) on bone metabolism is not investigated. We examined the effect of CLTIHH on bone metabolism and the role of nitric oxide (NO) in this process. The rats were divided into three groups in this study. The animals in groups I and II have been exposed to CLTIHH. The animals in group II were also treated with nitric oxide synthase inhibitor NG-nitro-l-arginine methyl ester. To obtain CLTIHH, rats were placed in a hypobaric chamber (430 mm Hg; 5 h/day, 5 days/week, 5 weeks). The group III (control) rats breathed room air in the same environment. At the begining of the experiments, bone mineral density (BMD) of the animals were measured, and blood samples were collected from the tail vein. After the 5-week CLTIHH period, the same measurements were repeated. Parathyroid hormone, calcium, phosphate, bone alkaline phosphatase (b-ALP), NO, interleukin 1 beta, interleukin 6, and tumor necrosis factor alpha levels were determined. The cytokines, NO levels, and BMD in CLTIHH-induced rats were higher compared with baseline and control values. The cytokines, b-ALP, and BMD increased while NO levels decreased in the group II compared with baseline values. BMD values of group II were lower than group I but higher than control group. Our results suggested that CLTIHH has positive effects on bone density. Intermittent hypoxia protocols may be developed for treatment and prevention of osteopenia and osteoporosis. 相似文献
70.
Sergej Tschernyschkow Sabine Herda Gerd Gruenert Volker Döring Dennis Görlich Antje Hofmeister Christian Hoischen Peter Dittrich Stephan Diekmann Bashar Ibrahim 《Progress in biophysics and molecular biology》2013