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61.
Involvement of Protein and Ribonucleic Acid in the Association of Deoxyribonucleic Acid with Other Cell Components of Escherichia coli 总被引:2,自引:1,他引:1
Cells of Escherichia coli were labeled with precursors of ribonucleic acid (RNA), deoxyribonucleic acid (DNA), and protein, lysed with detergent, and examined by starch-block electrophoresis and CsCl density gradient centrifugation. A large amount of the DNA was seen to remain at positions of low electrophoretic mobility and light density along with tryptophan and arginine-containing proteins and some RNA. Addition of labeled, phenol-extracted DNA to unlabeled cells prior to lysis and electrophoresis showed that only a small amount of the DNA became associated during or after lysis. Sonic treatment of a lysate removed most of the DNA to a position of electrophoretic mobility and density similar to that of free DNA, whereas pronase and ribonuclease released only a part of the DNA. We concluded that binding of DNA to cell membranes or other cell components occurs in the cell prior to lysis and involves protein and probably a specific type of RNA. 相似文献
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Connie Suk-Han Ho Bonnie Wing-Yin Chow Simpson Wai-Lap Wong Mary M. Y. Waye Dorothy V. M. Bishop 《PloS one》2012,7(10)
The Simple View of Reading (SVR) in Chinese was examined in a genetically sensitive design. A total of 270 pairs of Chinese twins (190 pairs of monozygotic twins and 80 pairs of same-sex dizygotic twins) were tested on Chinese vocabulary and word reading at the mean age 7.8 years and reading comprehension of sentences and passages one year later. Results of behavior-genetic analyses showed that both vocabulary and word reading had significant independent genetic influences on reading comprehension, and the two factors together accounted for most but not all of the genetic influences on reading comprehension. In addition, sentence comprehension had a stronger genetic correlation with word reading while passage comprehension showed a trend of stronger genetic overlap with vocabulary. These findings suggest that the genetic foundation of the SVR in Chinese is largely supported in that language comprehension and decoding are two core skills for reading comprehension in nonalphabetic as well as alphabetic written languages. 相似文献
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Summary Methods for isolation of hybrids of industrial yeast strains, obtained by PEG-mediated protoplast fusion, using mitochondrial mutations to antibiotic resistance and to the petite condition as markers, are described. One of the industrial prototrophic strains, carrying a rescuable mutation to antibiotic resistance, was converted to the petite form, and protoplasts obtained from it were fused with protoplasts from antibiotic-sensitive prototrophic strains of brewing and distiller's yeasts or with an auxotrophic laboratory strain carrying several chromosomal mutations. The parent of the petite strain was also able to metabolize starch, which was used as an additional character for confirming the hybrid nature of the strains isolated on the basis of their antibiotic resistance.Presented in part at the 5th International Protoplast Symposium held at the Attila Josef University, Szeged, Hungary, July 9–14, 1979 相似文献
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Pamela McElwee Katherine Calvin Donovan Campbell Francesco Cherubini Giacomo Grassi Vladimir Korotkov Anh Le Hoang Shuaib Lwasa Johnson Nkem Ephraim Nkonya Nobuko Saigusa Jean‐Francois Soussana Miguel Angel Taboada Frances Manning Dorothy Nampanzira Pete Smith 《Global Change Biology》2020,26(9):4691-4721
Interlocked challenges of climate change, biodiversity loss, and land degradation require transformative interventions in the land management and food production sectors to reduce carbon emissions, strengthen adaptive capacity, and increase food security. However, deciding which interventions to pursue and understanding their relative co‐benefits with and trade‐offs against different social and environmental goals have been difficult without comparisons across a range of possible actions. This study examined 40 different options, implemented through land management, value chains, or risk management, for their relative impacts across 18 Nature's Contributions to People (NCPs) and the 17 Sustainable Development Goals (SDGs). We find that a relatively small number of interventions show positive synergies with both SDGs and NCPs with no significant adverse trade‐offs; these include improved cropland management, improved grazing land management, improved livestock management, agroforestry, integrated water management, increased soil organic carbon content, reduced soil erosion, salinization, and compaction, fire management, reduced landslides and hazards, reduced pollution, reduced post‐harvest losses, improved energy use in food systems, and disaster risk management. Several interventions show potentially significant negative impacts on both SDGs and NCPs; these include bioenergy and bioenergy with carbon capture and storage, afforestation, and some risk sharing measures, like commercial crop insurance. Our results demonstrate that a better understanding of co‐benefits and trade‐offs of different policy approaches can help decision‐makers choose the more effective, or at the very minimum, more benign interventions for implementation. 相似文献
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James J. Lewis Katherine L. Fielding Alison D. Grant Violet N. Chihota Flora Popane Mariette Luttig Dorothy Muller Leonie Coetzee Gavin J. Churchyard 《PloS one》2013,8(11)