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The dynamics of125I distribution is studied in rats with induced tumors of the prostate and mammary gland for intravenous administration of125I-3D-G. It is found that 80% of the activity is eliminated in the first 24 hours. A relatively high level of125I accumulation is found in necrotically altered regions of the tumor. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, № 3, pp. 294–295, March, 1994.  相似文献   
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A study of 30 patients with infectious-allergic myocarditis, accompanied with chronic heart failure made use of echocardiography, hemodynamic assessment by cardiac catheterization, endomyocardial biopsy. A relationship is demonstrated between hemodynamic changes and the lesion of cellular ultrastructural apparatus, mitochondria, in particular. Patients with first-stage heart failure associated with infectious-allergic myocarditis showed incomplete diastole, while systolic changes were found in patients with severe manifestation of circulatory insufficiency.  相似文献   
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The monomer composition and sequence distribution in ethylene-propylene copolymers (EPCs) obtained with supported titanium/magnesium (TMC) and vanadium/magnesium (VMC) catalysts as well as with titanium trichloride was studied by means of 13C NMR spectroscopy. Based on these data ethylene-propylene reactivity ratios were determined. The EPCs obtained on these catalysts are inhomogeneous in composition; the soluble fractions contain larger amounts of propylene. The microstructures of copolymers obtained on TMCs and TiCl3 are similar. For EPCs obtained on VMCs, propylene “head-to-head” or “tail-to-tail” inversions and a more homogeneous distribution of propylene are observed.  相似文献   
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ESR was used for studying the interaction between the stable nitroxyl radical TEMPO (2,2,6,6-tetramethylpyperidin-1-oxyl) and the titanium-magnesium catalysts TiCl4/MgCl2 and TiCl4/MgCl2 · nD (D is either diisobutyl phthalate or 2,2-diisobutyl-1,3-dimethoxypropane), as well as TiCl4/MgCl2 · nD treated with triethylaluminium. In all cases, only part of the surface titanium complexes (18–53 mol-%) exhibit Lewis acid properties and can interact with TEMPO. The portion of titanium complexes with acidic properties depends on the composition and preparation of the catalysts, and it decreases upon treatment with triethylaluminium.  相似文献   
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In order to find out correlations between the structure of an external donor and the obtained polymer, the effects of different external donors on the activity and stereospecificity of the MgCl2/TiCl4 catalytic system in the bulk polymerization of 4-methyl-1-pentene (4MP) were carefully studied. Different silane compounds of the structure RnSi(OR')4-n (where: n = 1–3, R = alkyl/phenyl, R = alkyl) and Al(i-Bu)3 (TIBA) were used as external donors and cocatalyst, respectively. The effect of the donor/TIBA mole ratio on the activity and stereospecificity of the catalytic system was studied. Some major effects were observed for the three different external donors, namely, Me3Si(OMe), Me2Si(OMe)2, and Me3Si(OBu)3, in the 4MP polymerization process. It was observed that the effect of the external silane donor on the polymerization strongly depends upon the size of the alkoxy and hydrocarbon (alkyl/phenyl) groups which are attached to the silicon atom. A selective deactivation of the non-stereospecific centers, as well as a transformation of the non-stereospecific into isospecific centers, is assumed to occur. On the basis of the obtained results and literature data available for the propene polymerization, the concept of structural conformity between the ligand-surrounded active center and the monomer molecule was carried forward.  相似文献   
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Summary Temporary growth and the following resolution of the Brown-Pearce tumor transplanted subcutaneously into the rabbit's ear causes development of complete immunity to the secondary transplantation of this tumor into the testicle.Vaccination by saline extract of Brown-Pearce tumor or by an extract of the tumor prepared with normal rabbit serum produces no immunity in rabbits.Presented by Active Member Acad. Med. Sci. USSR N. N. Zhukov-Verezhnikov  相似文献   
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