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1.
The effect of UV light (lambda = 254 nm) on calf thymus DNP at low ionic strengths was studied. It was found that at the irradiation doses used the protein in the DNA-protein complex increases as the irradiation dose rises. Thermal treatment and acid hydrolysis resulted in a predominant release of histones H3 and H1 from the complex. Data from liquid high performance chromatography, amino acid analysis, thin-layer chromatography point to the induction by UV-light of a thymine-lysine bond, whose formation involves DNA thymines and histone lysine residues, predominantly H3 and H1 fractions. 相似文献
2.
Indomethacin and substance BW-755C in experiments on isolated myometrium striae of pregnant white rats exert an inhibiting effect on the contractile uterus function due to inhibition of cyclooxygenase or lipoxygenase ways of the arachidonic acid transformation. Prostaglandin F2 alpha is sensitive to functioning of the cyclooxygenase and lipoxygenase ways of the arachidonic acid transformation, while oxytocin--only lipoxygenase one. Conclusions rest on results from multiparametric analysis of the contractile uterus function suggested by authors and confirmed by the pattern recognition method--the Karunen-Loev orthogonal decomposition. 相似文献
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The effect of transcranial magnetic stimulation (TMS) of the right and the left frontotemporal areas on the short- and long-term verbal memory was studied in healthy subjects and patients with Parkinson’s disease. TMS with a magnetic induction of more than 1.2 T at 10 Hz was found to affect the short-term memory when applied to the left frontotemporal area and to have no significant effect on this type of memory when applied to the right frontotemporal area. In healthy subjects, TMS applied to the left or the right hemisphere did not affect the long-term memory. However, in patients with Parkinson’s disease, significant changes in the long-term memory were observed upon TMS of either the left or the right hemisphere. The effect was more evident on TMS of the right hemisphere.__________Translated from Fiziologiya Cheloveka, Vol. 31, No. 4, 2005, pp. 33–36.Original Russian Text Copyright © 2005 by Gimranov, Mal’tseva. 相似文献
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In vitro incubation of thymocytes with [2-14C]acetate results in a more intensive label incorporation into chromatin lipids as compared to nuclear lipids. The deleterious effect of gamma-irradiation leads to specific changes in [2-14C]acetate incorporation into the total fraction of phosphatidylcholine-phosphatidylserine and chromatin sphingomyelin. This is paralleled with an increase in the ratio of specific radioactivities of chromatin cardiolipin and nuclear cardiolipin. The changes in specific radioactivities of sphingomyelin, phosphatidylcholine-phosphatidylserine and cardiolipin suggest a role of phospholipids in the mechanisms of regulating the activity of intranuclear structures. 相似文献
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V B Gerazieva I G Mikha?lov T D Kanare?tseva 《Biulleten' eksperimental'no? biologii i meditsiny》1975,80(10):93-96
A change in the activity of succinic dehydrogenase, of the NAD- and NADP-diaphorases was studied in the dissociated culture of the cerebellum of neonatal rats under the effect of immune serum of the animals with an experimental allergic pertussis encephalomyelitis. There was revealed an increase in the activity of oligodendrocytes following a 3-hour exposure with the immune serum and a reduction of the activity of the enzymes under study in the same cells after a 12-hour exposure of the cultures with the serum. In difference from oligodendrocytes, the astrocytes displayed a high activity of all the enzymes under study after a 12-hour exposure. 相似文献
9.
V Ia Bykhovski? N I Za?tseva A F Mironov N S Osin E V Pecherskikh V D Rumiantseva G M Sukhin 《Prikladnaia biokhimiia i mikrobiologiia》2001,37(6):660-668
Methods of synthesis of coproporphyrin and uroporphyrin by using bacteria of the genus Arthrobacter are proposed. Metal complexes of coproporphyrin and uroporphyrin with Pt, Pd, and Zn were synthesized. Their structures were identified by spectrophotometry, IR spectrometry, 1H-NMR, mass spectrometry, and HPLC. Data showing the possibility to use coproporphyrin III-metal complexes as luminophores for fluorescence detection of tumors. The current and prospective uses of metal complexes of water-soluble natural porphyrins in advanced immunofluorescence assays are discussed. 相似文献
10.
S M Borodkin O M Grindel' G N Boldyreva V A Za?tsev V I Luk'ianov 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》1987,37(1):22-30
EEGs of 15 healthy subjects and 30 patients in early period after surgical ablation of tumours with basal localization, were investigated by means of monitor "Neuro-1" which allows to obtain in continuous regime characteristics of EEG dynamics according to power spectra and reveal the characteristics of intercentral relations of electrical brain processes by coherence and phase shifts. In healthy subjects in the period of transition from wakefulness to drowsiness highly coherent beta-rhythm (16-18 Hz) was revealed, preceeding typical picture of drowsiness and sleep. Study of the patients shows that certain characteristics of coherence and phasic shifts have an important prognostic value. Conclusion is made that for estimation of the functional state of healthy subjects during transition from wakefulness to drowsiness and of patients in early postoperative period the data on spectra of coherence are most informative. 相似文献