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81.
The paper is devoted to analysis of the potentialities of radionuclide renography as a method for assessment of the effectiveness of radiotherapy of bladder cancer. The results obtained suggested close correlation between change of renal function and the results of irradiation. Normal renal function was observed in 3 patients, improvement--in 16 patients, and deterioration--in 8 patients whereas a complete effect of radiotherapy brought about the following figures: 5, 11 and 3, respectively. A conclusion was made of a high significance of renography parameters in objective assessment of the results of radiotherapy of bladder cancer in conjunction with other therapeutic modalities.  相似文献   
82.
Immunohistochemistry was used to study the changes in the number of G cells in the antral part of the stomach of rats (40 animals) with cystamine-induced duodenal ulcer treated with beta-endorphine. In the stomach of rats with cystamine-induced ulcer the number of G cells was discovered to be significantly increased, which was removed by an opioid peptide. Naloxone did not block the action of beta-endorphine. Thus, beta-endorphine changes the number of G cells, the drug action being not associated with opiate receptors.  相似文献   
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The cytoplasmic hemoglobin III from the gill of the symbiont-harboring clamLucina pectinata consists of 152 amino acid residues, has a calculated Mm of 18,068, including heme, and has N-acetyl-serine as the N-terminal residue. Based on the alignment of its sequence with other vertebrate and nonvertebrate globins, it retains the invariant residues Phe45 at position CD1 and His98 at the proximal position F8, as well as the highly conserved Trp16 and Pro39 at positions A12 and C2, respectively. The most likely candidate for the distal residue at position E7 is Gln66.Lucina hemoglobin III shares 95 identical residues with hemoglobin II (J. D. Hockenhull-Johnsonet al., J. Prot. Chem. 10, 609–622, 1991), including Tyr at position B10, which has been shown to be capable of entering the distal heme cavity and placing its hydroxyl group within a 2.8 Å of the water molecule occupying the distal ligand position, by modeling the hemoglobin II sequence using the crystal structure of sperm whale metmyoglobin. The amino acid sequences of the twoLucina globins are compared in detail with the known sequences of mollusc globins, including seven cytoplasmic and 11 intracellular globins. Relative to 75% homology between the twoLucina globins (counting identical and conserved residues), both sequences have percent homology scores ranging from 36–49% when compared to the two groups of mollusc globins. The highest homology appears to exist between theLucina globins and the cytoplasmic hemoglobin ofBusycon canaliculatum.  相似文献   
88.
Orthologs are genes from different genomes that originate from a common ancestor gene by speciation event. They are most similar by the structure of encoded proteins and therefore should have a similar function. Here I apply the principle used for detection of structural orthology for a genome-wide analysis of gene expression. For this purpose, I determine the mutual similarity rank in all-by-all comparison of among-tissues expression patterns. The expression of most part of human–mouse orthologs in homologous tissues is poorly correlated (average mutual coexpression rank is only 4835 out of 18,092). Genes from evolutionarily labile gene families, which experience rapid turnover of family composition, are among those with the strongest expression change. However, the revealed phenomenon is not limited to them. There is no or very weak relationship between protein sequence divergence and mutual coexpression rank. Also, generally there is no relationship between the ratio of nonsynonymous to synonymous nucleotide substitutions and coexpression rank. This relationship is tangible only within evolutionarily labile gene families. These results indicate that despite of a similar biochemical function of orthologs reflected in the conserved protein sequence, the physiological (systemic) context of this function can be changed. Also, these results suggest that gene biochemical function and its physiological role in the organism can evolve independently.  相似文献   
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To enhance the penetration of oligonucleotide ('oligo') into cells, the oligo was combined with the hydrophobic undecyl residue. Using the 'DNA-synthesator', we synthesized oligo, complementary to the loop-forming site of the RNA, encoding polymerase 3 of the influenza virus (type A), and combined it with the undecyl residue added to the 5' terminal phosphate group. It was found that the modified oligo effectively suppresses the influenza A/PR8/34 (H1N1) virus reproduction and inhibits the synthesis of virus-specific proteins in MDCK cells. Under the same conditions, the non-modified antisense oligo and modified nonsense oligo did not affect the virus development.  相似文献   
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Three new bisbenzimidazole (BBI) compounds, which differ from Hoechst 33258 mainly by substitution of a N-dimethylaminopro-pylcarboxamide group in place of the N-methyl-piperazine ring, were studied for their DNA- and AT-base pair specificity as well as for their ability to be quenched by incorporated 5-bromodeoxy-uridine (BrdU). Each of them had DNA binding specificity comparable to or greater than that of Hoechst 33258 and each had a greater specificity for AT-rich regions than did Hoechst 33258. The dependence of fluorescence of new dyes on the BrdU-incorporation into DNA is different from that of Hoechst 33258 and related compounds with piperazine ring. The quenching effect is much weaker, and two of the new compounds (BBI-1 and BBI-2) even show somewhat enhanced binding (fluorescence) at lower concentrations. Certain BBI dyes without piperazine ring may have some advantage over Hoechst for accurate DNA [AT-specific] measurements. The piperazine ring appears to play an important role in the yet unknown mechanism of Hoechst quenching by incorporated BrdU.  相似文献   
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