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911.
It was demonstrated that the nuclear matrix of rat liver possesses the protease activity. The specific activity of nuclear matrix proteases exceeds that of intact nuclei 7-fold. The optimum activity of nuclear matrix proteases is observed at pH 8-9. The protease activity of the nuclear matrix is inhibited by p-chloromercuribenzoate, N-ethylmaleimide, EDTA, phenylmethylsulfonyl fluoride. This suggests that thiol, serine and metalloproteases are associated with the nuclear matrix. 相似文献
912.
I E Ganelina L M Kukui J P Nikolaewa T E Schumilowa W E Cholmogorow K W Timofeew A L Schurigin 《Folia haematologica (Leipzig, Germany : 1928)》1982,109(3):470-482
We observed 70 male patients with a seriously proceeding Chronic myocardial ischemia. They were hospitalised because of frequent, permanent and serious attacks of stenocardia at rest and in stress situations. More than 2/3 of these patients had suffered from a myocardial infarct. In the course of two weeks an intensive therapy with all modern preparations for vasodilatation was made. This therapy proved to be unsuccessful. Nearly all patients were administered more than 10 tables of nitroglycerin per day and, in addition, they were injected analgetics as a compensation of attack. The ultraviolet own blood irradiation (UVB) had a positive therapeutic effect in all patients. There was a good success in 46 patients, in all patients satisfactory results could be registered. The effect of therapy was evident by the decrease of administration of nitroglycerin required, by an increase in the degree of stress capacity, and by an easier treatment of stenocardia attacks. The observation time for patients amounted to 2-8 months. The success of therapy remained in 38 patients. After this time the success of therapy could partially be regained by a repeated number of irradiation series. Then, it remained positive in 9 of 22 patients who had been followed-up for 10 months. The half decay period of eliminating 131I from an intradermal depot could be normalised under the influence of ultraviolet own blood irradiation. This ultraviolet own blood irradiation had no significant influence on the fibrinogen level, fibrinolytic activity, and erythrocyte aggregation (examined in 11 patients). A 2 1/2-fold diminution of monomer fibrin complexes in the blood could be observed. The titre of antistreptolysin-O was increased in all patients who had got over the infarct. It had completely normalised a week after finishing the ultraviolet own blood irradiation. Spectroscopic examinations of the blood and plasma made after ultraviolet own blood irradiation revealed that this irradiation will not only affect the properties of Hb, but will also cause a photochemical transformation accompanied by a destruction of some plasma proteins, of the membrane of formed blood elements, and a photosynthesis of biochemically active compounds. The mechanism of action of ultraviolet own blood irradiation is complicated and requires further exact investigations. Even today, however, this method can be recommended as a complex therapy in patients with severe myocardial ischemia. 相似文献
913.
914.
915.
W Firshein 《Journal of molecular biology》1972,70(3):383-397
916.
917.
Density gradient analysis of newly replicated DNA from synchronized mouse lymphoma cells 总被引:3,自引:0,他引:3
The replication of DNA in synchronous cultures of mouse lymphoma cells was investigated by use of CsCl density gradient centrifugation. We found that the buoyant density of newly replicated DNA depended upon the particular stage of S phase in which synthesis occurred. In early S phase, newly replicated DNA exhibited buoyant densities which were slightly higher, on the average, than that of pre-existing DNA. As S phase progressed, newly replicated DNA shifted to lower buoyant densities, until, near the end of S phase, densities less than pre-existing DNA were observed. These observations are discussed in terms of their possible relevance to base compositional differences between nucleotide sequences made in early as opposed to middle or late S phase. 相似文献
918.
M R Kopantseva M Z Liudvig I I Uspenski? N A Tamarina V A Tsatrian L I Korochkin 《Zhurnal obshche? biologii》1990,51(1):125-140
A comparative electrophoretic study or ejaculatory bulb proteins in 29 different Drosophila species has been carried out. In all analyzed species, ejaculatory bulb contains a major component (designated as PEB). It has molecular mass of 61-65 kDa in the species of virilis group, 33-36 kDa in species of obscura group, and 34-56 kDa in species of melanogaster group. Using immunoblotting technique, we have demonstrated that PEB is introduced into organs of female sex tract during mating. The nature and significance of revealed interspecific differences in PEB proteins has been discussed. 相似文献
919.
920.
Physiological and molecular genetic mechanisms regulating hydrolytic enzyme gene expression in cereal grains 总被引:1,自引:0,他引:1
Ronald W. Skadsen 《Physiologia plantarum》1998,104(3):486-502