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961.
Evidence is presented that lactoferrin (LF), an Fe3+-binding glycoprotein, possesses two DNA-binding sites with different affinities for specific oligonucleotides (ODNs) (Kdl = 8 nM; Kd2 approximately 0.1 mM). The high affinity site became labeled after incubation with affinity probes for DNA-binding sites; like the antibacterial and polyanion-binding sites, this site was shown to be located in the N-terminal domain of LF. Interaction of heparin with the polyanion-binding site inhibits the binding of ODNs to both sites. These data suggest that the DNA-binding sites of LF coincide or overlap with the known polyanion and antimicrobial domains of the protein. 相似文献
962.
V Krajca 《Activitas nervosa superior》1984,26(2):118-128
Use of the dynamic clusters method for automatic extraction of compressed information about recorded EEG signal is presented. The computer first divides the record into quasi-stationary segments by means of adaptive segmentation. Second, the extracted segments are classified by a method of dynamic clusters into homogeneous classes. One part of the used clustering algorithm permits to specify and draw the most typical class members, which may represent the whole studied EEG signal and may be used as input for the further phase of the automatic EEG analysis, i.e. for the classification of the whole EEG records. The above procedure was applied to a 75 sec long EEG record of anaesthetized cat intoxicated by CO. 相似文献
963.
S K Tandon A K Mathur J R Behari S V Chandra 《Acta biologica et medica Germanica》1975,34(11-12):1835-1842
Daily intraperitoneal administration of thorium nitrate produced progressive morphological and biochemical alterations with the increase in thorium concentration in rat testis. The degenerative changes in the seminiferous tubules increased with the duration of treatment and after 90 days calcification occurred in about 25% of the tubules and in the connective tissue of the tunica albuginea. The activity of adenosine triphosphatase and alkaline phosphatase increased markedly as a result of thorium administration. An attempt has been made to interrelate histopathological and enzymatic changes and the metal concentration in the testicular tissue. 相似文献
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The frequency of spontaneous reversion in r-mutants of phage T4 is determined in order to study the influence of mutant RNA polymerase on the level of spontaneous mutations in phage T4. The rate of spontaneous mutagenesis in the phage is found to be increased in strains with mutant RNA polymerase. 相似文献