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1.
结合国内外低碳土地利用的研究背景和实践,分析出不同土地利用方式碳排放效应,并对城市土地低碳化与集约化利用进行定性与定量分析,并采用鄂州市实际构建低碳理念下城市土地集约利用评价指标体系,对鄂州市2000-2013年土地利用状况进行分析评价.由此,总结鄂州市再加入低碳因素后土地集约利用的变化规律,并提出相关建议.  相似文献   
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With the progress of science and technology, human beings explore the energy under-ground with thousands of meters. As a thermophysical parameter, initial formation temperature (IFT) plays an essential...  相似文献   
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在教学过程中通过对练习题: 的求解、分析、综合和归纳得: (1) 式中P_n(X)_9 Q_n(x)均为n次多项式,其中Q_n(x)的各项系数待定。 (2) 式中P_n(x)为n次多项式,f_(n-1)(x)为各项系数待定的(n-1)次多项式,μ_n为待定常数。  相似文献   
4.
论述了高师图书馆实施综合素质教育的意义和挑战,提出了共建具有专业特色的教育基地、优化整合教育资源、全面推进素质教育等培养高素质人才,落实人才强国战略的新举措。  相似文献   
5.
The autosomal recessive disorder Shwachman-Diamond syndrome, characterized by bone marrow failure and leukemia predisposition, is caused by deficiency of the highly conserved Shwachman-Bodian-Diamond syndrome (SBDS) protein. Here, we identify the function of the yeast SBDS ortholog Sdo1, showing that it is critical for the release and recycling of the nucleolar shuttling factor Tif6 from pre-60S ribosomes, a key step in 60S maturation and translational activation of ribosomes. Using genome-wide synthetic genetic array mapping, we identified multiple TIF6 gain-of-function alleles that suppressed the pre-60S nuclear export defects and cytoplasmic mislocalization of Tif6 observed in sdo1Delta cells. Sdo1 appears to function within a pathway containing elongation factor-like 1, and together they control translational activation of ribosomes. Thus, our data link defective late 60S ribosomal subunit maturation to an inherited bone marrow failure syndrome associated with leukemia predisposition.  相似文献   
6.
Summary A study was undertaken on the variations of the redox potential level produced by streptomycinin vitro andin vivo. We have been able to show that, owing to an oxidative effect, streptomycin produces an increase of the redox potential level. This oxidative effect varies in degree according to the condition of the patient.We also found that in the blood and in the spinal fluid of patients suffering from tubercular meningitis factors are present which inhibit the action of streptomycin.The results of our findings lead to the conclusion that the dose of streptomycin must be varied according to the condition of the patient if the constant level required for an efficient therapy is to be maintained in the blood and in the spinal fluid.  相似文献   
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Summary By condensing 2:4:5-triamino-6-hydroxy-pyrimidine with dihydroxyacetone (diacetate), diaminoacetone or acetone-1,3-di (p-formylaminobenzoic acid) not the expected 8- or 9-oxymethyl resp. -aminomethyl-pteridines but 8-or 9-methyl-pteridines were obtained. With p-tolyl-d-isoglucosamine not a tetrahydroxybutyl-pteridine but a trihydroxybutyl-pteridine was formed. For an explanation of these results it is supposed that from the dihydro-pteridines formed at first by intramolecular splitting off of H2O or R·NH2 aromatization takes place.  相似文献   
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Refsum disease is a rare, inherited neurodegenerative disorder characterized by accumulation of the dietary branched-chain fatty acid phytanic acid in plasma and tissues caused by a defect in the alphaoxidation pathway. The accumulation of phytanic acid is believed to be the main pathophysiological cause of the disease. However, the exact mechanism(s) by which phytanic acid exerts its toxicity have not been resolved. In this study, the effect of phytanic acid on mitochondrial respiration was investigated. The results show that in digitonin-permeabilized fibroblasts, phytanic acid decreases ATP synthesis, whereas substrate oxidation per se is not affected. Importantly, studies in intact fibroblasts revealed that phytanic acid decreases both the mitochondrial membrane potential and NAD(P)H autofluorescence. Taken together, the results described here show that unesterified phytanic acid exerts its toxic effect mainly through its protonophoric action, at least in human skin fibroblasts. Received 4 August 2007; received after revision 26 September 2007; accepted 10 October 2007 J. C. Komen, F. Distelmaier: These authors contributed equally to this work.  相似文献   
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