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31.
The microflora inhabiting the intestinal mucosa of the pike and the tegument surface of the intestinal parasite Triaenophorus nodulosus is investigated. By means of electron microscopy, the ultrastructural features of bacteria and pattern of their interaction
with the colonized surfaces are estimated. Specific distribution of microorganisms belonging to different morphotypes and
subdivided into subpopulations on the colonized surfaces is found. Predominance of gram-negative bacteria in all studied microbiocenoses
and abundance of nanobacteria in the “superficial” subpopulations are observed. The bacteria of “a deep population” associated
with the basal parts of microtrichiae and microvilli are described. It is concluded that the helminthes, the fish parasites
possess the normal microflora characterized by specific composition, by ultrastructural features of cells, and by patterns
of interaction with the helminth surface. The obtained data characterize the mechanisms of symbiotic interaction of prokaryotes
and eukaryotes in the system parasite-host-symbiotic microflora. 相似文献
32.
G G Ivanov V A Vostrikov M S Bogushevich O S Medvedev Zh D Bespalova 《Biulleten' eksperimental'no? biologii i meditsiny》1992,113(5):463-464
Results of the study of taurine and dipeptide Tyr-Tyr effect on the threshold values of functional lesions of the myocardium and heart defibrillation are reported. The experiments were carried out on 27 narcotized mongrel dogs weighing 12-30 kg. Defibrillation was performed using Lifepak-7 defibrillator (USA). Lesion threshold (LT), defibrillation threshold (DT) and electrotherapeutic index (ETI) as a LT:DT ratio were determined. In 14 experiments (control group) these parameters were evaluated during 3 h. In group 1 (6 experiments) taurine (100 mg/kg) was infused intravenously by the end of the 1st hour, in group 2--Tyr-Tyr (25 mg/kg). It was shown that infusion of taurine did not have a noticeable effect of the LT, DT and ETI values. Infusion of Tyr-Tyr resulted in an increase in LT and DT. The possibility to use dipeptide Tyr-Tyr in the complex of measures aimed at ceasing ventricular fibrillation is discussed. 相似文献
33.
M. E. Palkeeva M. V. Sidorova A. S. Molokoedov A. A. Az’muko Zh. D. Bespalova T. V. Sharf E. N. Mamochkina E. E. Efremov M. M. Rogova N. A. Mironova K. A. Zykov S. P. Golitsyn 《Russian Journal of Bioorganic Chemistry》2013,39(3):252-258
Fragments corresponding to the 83–98 sequence of the first extracellular loop and to the 168–192 and 171–182 sequences of the second extracellular loop of the M2-muscarinic receptor (antibodies to this receptor could be markers of early symptoms of heart disorders) were synthesized by solid phase method using the Fmoc-SPPS strategy. A new conformational antigen with the natural location of the disulfide bridge was prepared by selective formation of disulfide bond between the corresponding cysteine residues in the synthe-sized peptides and characterized. The comparative analysis of reactivity of the synthesized peptides towards sera from patients which had no organic heart disease was performed. A new conformational antigen was effectively bound to the sera from patients with idiopathic arrhythmias, but without symptoms of organic heart disease. 相似文献
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G A Tolstikov L A Baltina R M Kondratenko Kh M Nasyrov N Zh Baschenko 《Bioorganicheskaia khimiia》1989,15(3):392-398
Three triterpene glycopeptides, glycyrrhizic acid monomethly ester derivatives containing peptide fragment of N-acetylmuramoyldipeptide and its analogues, are synthesized. They possess high prednizolone-like antiinflammatory activity and display pronounced stimulative effect on humoral factors of immunity. 相似文献
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The ultrastructure of the mid-intestine of four sturgeon species and their hybrids was studied. Apart from enterocytes and
glandular goblet cells, the cells with microvilli, endocrine cells, and immunocompetent elements were revealed. Specific cells
responsible for the primary immune response, analogous to mammalian M-cells, were discovered in sturgeon fishes. The ultrastructural characteristics common for the mid-intestinal epithelium of
all the sturgeon fishes studied were determined. Species-specific features of intestinal epithelium of the parent species,
which were characteristic of the hybrids, were revealed. 相似文献
40.