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V. K. Bozhenko E. V. Khmelevskii A. M. Shishkin V. N. Vasil'ev A. G. Zakharov V. I. Kiselev 《Bulletin of experimental biology and medicine》1994,117(3):297-299
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
3.
Silvia Samarin Lovric Viktor Avbelj Roman Trobec Darko Zorman Peter Rakovec Sergej Hojker Borut Gersak Metka Milcinski 《European journal of cardio-thoracic surgery》2004,26(4):736-741
OBJECTIVE: Complete allograft denervation occurs during heart transplantation. Partial ventricular sympathetic reinnervation may develop one year or later after transplantation and can be measured with iodine-123-meta-iodobenziylguanidine (MIBG) uptake. Aim of this study was to assess sinus node sympathetic reinnervation measured with heart rate variability and ventricular sympathetic reinnervation evaluated with MIBG. METHODS: Twelve patients and 14 healthy controls were included. In patients, MIBG scintigraphy with early and late imaging was performed. Heart to mediastinum ratio (HMR) was calculated and patients were divided in groups with (HMR>1.3) and without left ventricular reinnervation (HMR<1.3). Bipolar ECG with high sampling rate and resolution was recorded over 8.5 min in supine position and in upright position after 10 min interval. R-R intervals in time domain and heart rate variability in frequency domain through spectral power analysis of R-R intervals were analysed to evaluate sinus node reinnervation. Spectral power in low frequency range (0.04-0.15 Hz) above 4.5 ms(2) was considered as sinus node sympathetic reinnervation. RESULTS: Six (50%) patients had evidence of left ventricular sympathetic reinnervation on scintigraphy. Sinus node sympathetic reinnervation based on heart rate variability was detected in 6 (50%) patients in supine, and in 4 (33%) patients in upright body position. Four patients groups were discerned: (1) with ventricular and sinus node sympathetic reinnervation, (2) with sinus node sympathetic reinnervation, (3) with ventricular sympathetic reinnervation and (4) without atrial or ventricular sympathetic reinnervation. Ventricular reinnervation process was time dependent and sinus node reinnervation was not. CONCLUSIONS: Simultaneous ventricular sympathetic reinnervation assessed by MIBG and sinus node sympathetic reinnervation assessed by heart rate variability in supine as in upright position were detected only in two patients (17%). The results of our study show that eventual sinus node sympathetic reinnervation and left ventricular sympathetic reinnervation do not occur simultaneously. 相似文献
4.
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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Lyudmila G. Yechevskaya Gennadii D. Bukatov Vladimir A. Zakharov Andrey V. Nosov 《Macromolecular chemistry and physics.》1987,188(11):2573-2583
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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Alexandr G. Potapov Vladimir A. Zakharov Tatijana B. Mikenas Sergeyi A. Sergeev Alexandr M. Volodin 《Macromolecular chemistry and physics.》1997,198(9):2867-2873
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
9.
Ilia Frolov Vladimir Kleiner Boris Krentsel Robert Mardanov Kalyan Munshi Gennady Bukatov Vladimir Zakharov Sergey Sergeev 《Macromolecular chemistry and physics.》1993,194(8):2309-2321
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
10.
A. F. Zakharov 《Bulletin of experimental biology and medicine》1958,45(2):240-243
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