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U Mura A M Osman A S Mohamed D Di Martino P L Ipata 《Comparative biochemistry and physiology. B, Comparative biochemistry》1987,87(1):157-160
The preservation of purine ring as purine bases appears to be a common feature of camel liver. Hepatic guanine appears to be actively converted into GMP in the camel rather than further degraded. The limiting step of guanine degradation appears to be the lack of hepatic guanase activity. Higher purine bases over uric acid ratios were found in camel urine with respect to those of zebu. 相似文献
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As business imperatives change and new high-capability information technologies (IT) appear, organizations recognize the need to remain at the forefront of change by reengineering their business processes and implementing enabling responsive IT infrastructures. However, experience in this context indicates a lack of comprehension of essential elements and their mutual relationships that can contribute to the success of business-process change-implementation efforts. This article proposes a framework for managing IT for effective business-process redesign (BPR) implementation. After establishing BPR principles, components, and the relationship of BPR to some organizational and technological approaches, it presents the role and benefits of IT in BPR. The article then discusses in detail the core elements of the framework. Its theme is that an IT infrastructure that covers issues of BPR strategy development, IT strategic alignment, IT infrastructure development, IT sourcing, legacy systems reengineering, IS integration, and IS function competence is essential and critical for effective implementation. 相似文献
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In experimentally infected insects, the sex ratio of first generation nematodes of five species of Steinernema was female-biased (male proportion 0.35-0.47). There was a similar female bias when the worms developed in vitro (0.37-0.44), indicating that the bias in these species is not due to a lower rate of infection by male infective juveniles (IJs). Experimental conditions influenced the proportion of males establishing in insects, indicating that male and female IJs differ in their behaviour. However, there was no evidence that males are the colonising sex in any species, contrary to what has previously been proposed. Time of emergence from the host in which the nematodes had developed influenced sex ratios in experimental infections. In three species (Steinernema longicaudum, Steinernema glaseri and Steinernema kraussei), early emerged nematodes had a higher proportion of males than those that emerged later, with the reverse trend for Steinernema carpocapsae and Steinernema feltiae. In a more detailed in vitro study of S. longicaudum, the proportion of males was similar whether or not the nematodes passed through the developmentally arrested IJ stage, indicating that the female bias is not due to failure of males to exit this stage. The sex ratio in vitro was independent of survival rate from juvenile to adult, and was female-biased even when all juveniles developed, indicating that the bias is not explained by failure of males to develop to adults. The female-biased sex ratio characteristic of Steinernema populations appears to be present from at least the early juvenile stage. We hypothesise that the observed female bias is the population optimal sex ratio, a response to cycles of local mate competition experienced by nematodes reproducing within insect hosts interspersed with periods of outbreeding with less closely related worms following dispersal. 相似文献
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Mangoes (Mangifera indica) are grown in many warm regions of the world; for example, in Australia, Brazil, India, South America, and the United States (California and Florida), and along the shores of the Mediterranean sea (Egypt, Italy, and Spain). In Egypt, many varieties yielding delicious fruits are grown in large quantities (50,000 tons annually). Mango kernels are used for feeding mammals and chickens. Starch has been isolated from mango and its physical properties studied.The aim of the present work was to study the polysaccharides present in mango kernels. 相似文献
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Thirty-eight genera and 81 species of fungi were isolated and identified from 120 samples of 24 kinds of spices collected from different places at Assiut Governorate, Egypt. Predominant genera wereAspergillus (25 species) andPenicillium (7 species) of whichA. flavus, A. niger, A. ochraceus, A. fumigatus, A. flavus var.columnaris, A. terreus, P. chrysogenum andP. corylophilum were the most commonly occurring. 相似文献
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Toxigenesis of Gibberella zeae strains NHL-F-1372 and NHL-F-1373 was compared in liquid and rice culture. Growth of both strains in glucose-yeast extract-peptone medium (GYEP) for 25 days resulted in peak levels of fusarenon X (FX) ranging from 40–200 mg/L with lower levels of nivalenol (NIV) (10 mg/L). Growth of these strains in modified Fries medium amended with 4% corn steep liquor (CSL) resulted in a much lower total 8-ketotrichothecene yield than in GYEP, with NIV being the primary compound produced. Although FX appeared initially in this latter medium, the toxin disappeared concurrently as the pH exceeded 8.0. Growth rates and total mycelial accumulation were lower in GYEP cultures than in the modified Fries with CSL cultures. Appearance of FX and NIV in modified Fries medium with CSL paralleled the order of appearance of these compounds in rice, but the total trichothecene yield in rice was much higher. In general, growth and toxigenesis by the nivalenol-producing fusaria in liquid and rice cultures was qualitatively similar to that previously found for deoxynivalenol-producing isolates.Michigan State University Agricultural Experiment Station Article No. 11700. 相似文献
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Abstract: cis -Methyldioxolane (CD) is a muscarinic receptor agonist. [3 H] CD has been used to label a subpopulation of muscarinic receptors described as exhibiting high agonist affinity. Pharmacological evidence suggests that the population of receptors labeled by [3 H] CD consists of m2 and/or m4 subtypes; however, no studies have directly addressed the subtype selectivity of [3 H] CD. The present study characterizes binding of this ligand to individual human receptor subtypes expressed in transfected Chinese hamster ovary cells. Results indicate that [3 H] CD binds with high affinity only to Hm2 receptors but not to all Hm2 receptors. Twenty-eight percent of Hm2 receptors bound [3 H] CD with a K D of 3.5 ± 0.5 nM. Binding was eliminated in the presence of guanosine 5'- O -(3-thiotriphosphate), indicating that the Hm2 receptors labeled by [3 H] CD are those that are associated with GDP-bound G protein. Binding of [3 H] CD by only a subpopulation of Hm2 receptors is in agreement with data generated from studies of [3 H] CD binding in mammalian brain. Because muscarinic receptors have been implicated to play a role in the pathogenesis of both Alzheimer's and Parkinson's disease, as well as the neurotoxicity of organophosphorus compounds, knowledge of the binding specificity of the muscarinic agonist [3 H] CD should aid research in these areas. 相似文献
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