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Nucleotide sequences of Plasmodium knowlesi DNA that are cleaved by mung bean nuclease (Mbn) at low enzyme concentration (0.2 units enzyme per micrograms DNA) are listed. They are tandemly repeated purine/pyrimidine (RpY) stretches of DNA with (ApT) dimers predominating. Most cut sites are within almost 100% RpY tracts. The enzyme cleaves at many points within the RpY stretch and usually hydrolyzes the 5'-ApT-3' linkage. These alternating RpY target sites are flanked by homopurine and homopyrimidine stretches. At least one Mbn target site lies next to an in vivo transcribed region. 相似文献
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Agnieszka Fischer Danuta Wiechuła Lidia Postek-Stefańska Jerzy Kwapuliński 《Biological trace element research》2009,132(1-3):19-26
The study shows the results of research on the concentrations of metals (Cd, Pb, Mn, Cu, Cr, Fe, Zn, Na, K, Mg, and Ca) in deciduous and permanent teeth with respect to their location in the oral cavity (maxilla, mandible). It has been found that the concentrations of metals were significantly higher in the deciduous teeth than in permanent ones. Regression analysis and principal component analysis revealed an increased dynamics of the processes of binding the elements by the hydroxyapatite of deciduous teeth. Higher concentrations of the metals were found in the maxilla permanent and deciduous teeth than in the mandible ones. 相似文献
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T Torlińska M Grzymis?awski J Paluszak P Sosnowski L Torliński J Ko?lik 《Acta physiologica Polonica》1987,38(4):353-360
Short (7 days) T3-treatment has no influence on the plasma glucose and FFA concentration and blood lactate level, as well as on the hepatic glycogen content in the rats. The rise in T3 levels, observed in our study, was accompanied by a fall in T4 concentrations, indicating suppression of the endogenous T4 production. On the other hand, glycogenolytic activity of rat serum in vitro is the highest in the system: control liver slices-serum of rats pretreated with T3 as compared to the system: control liver slices-control serum. These observations may lead to conclusions, that serum of rats pretreated with T3 contains factors exhibiting the greater ability to mobilize glucose from liver slices than the control serum (euthyroid). The possibility, that pretreatment with T3 may cause a decrease in the number and/or affinity of beta-adrenergic receptors in the rat liver, is discussed. 相似文献
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