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R Chakraborty 《American journal of human genetics》1991,49(4):895-7,899-903
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The acidic capsular polysaccharide isolated from Klebsiella K7 induced metachromasy in the cationic dye pinacyanol chloride indicating its chromotropic character. Interaction of the biopolymer with the cationic dye was studied by visible absorption spectrophotometry, and thermodynamic parameters of the interaction evaluated. The polymer induced a metachromatic blue shift in the spectrum from 600 nm to 495 nm. The spectral changes were studied during interaction of the dye with the polymer at different polymer/dye molar ratios (P/D = 0 approximately 50). Effects of co-solvents on the stability of the dye-polymer compound were studied. A complete reversal of metachromasy was observed upon addition of different alcohols and urea solution. Thermodynamic parameters obtained from the spectral data indicated chromotropic character of the polymer in interacting with the cationic dye molecules in solution. 相似文献
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A method was developed to optimize simultaneous selection for a quantitative trait with a known QTL within a male and a female line to maximize crossbred performance from a two-way cross. Strategies to maximize cumulative discounted response in crossbred performance over ten generations were derived by optimizing weights in an index of a QTL and phenotype. Strategies were compared to selection on purebred phenotype. Extra responses were limited for QTL with additive and partial dominance effects, but substantial for QTL with over-dominance, for which optimal QTL selection resulted in differential selection in male and female lines to increase the frequency of heterozygotes and polygenic responses. For over-dominant QTL, maximization of crossbred performance one generation at a time resulted in similar responses as optimization across all generations and simultaneous optimal selection in a male and female line resulted in greater response than optimal selection within a single line without crossbreeding. Results show that strategic use of information on over-dominant QTL can enhance crossbred performance without crossbred testing. 相似文献
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Experimental infection of hamsters with Leishmania donovani caused visceral leishmaniasis in which hematological changes occurred. The infected hamsters were anemic and reticulocyte counts were high. No significant change in the serum erythropoietin level was noted. Red cell membrane Na(+)-K(+)-ATPase and acetylcholinesterase activities increased. Osmotic fragility of the erythrocytes from infected animals increased. The level of 2,3-diphosphoglycerate of the red cells increased with the degree of anemia. 相似文献
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We formalise and present a new generic multifaceted complex system approach for modelling complex business enterprises. Our method has a strong focus on integrating the various data types available in an enterprise which represent the diverse perspectives of various stakeholders. We explain the challenges faced and define a novel approach to converting diverse data types into usable Bayesian probability forms. The data types that can be integrated include historic data, survey data, and management planning data, expert knowledge and incomplete data. The structural complexities of the complex system modelling process, based on various decision contexts, are also explained along with a solution. This new application of complex system models as a management tool for decision making is demonstrated using a railway transport case study. The case study demonstrates how the new approach can be utilised to develop a customised decision support model for a specific enterprise. Various decision scenarios are also provided to illustrate the versatility of the decision model at different phases of enterprise operations such as planning and control. 相似文献
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Cloning and sequence of beta tubulin cDNA from Giardia lamblia. 总被引:6,自引:1,他引:5