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81.
82.
In electrophysiological experiments in Wistar rats it was shown that preventive immunization of animals with bovine serum albumin conjugated with dopamine or 5-hydroxytryptamine or with bovine serum albumin alone partly protects against the development of experimental MPTP-induced depressive syndrome. Signs of depressive-like state such as decrease in REM-sleep latency and the development of epileptiform activity in caudate putamen were not observed in immunized animals, whereas REM-sleep proportion in the total sleep structure was increased. Changes in the spectral characteristics of brain electric activity and sleep structure during development of experimental MPTP-induced syndrome in immunized rats are antigen-specific and reflect the functional shifts in neurotransmitter systems, both in those which are the target of the immune action and those sensitive to alterations in the immune state of a body.  相似文献   
83.
The amount and composition of fatty acids in the fungus Stilbella aciculosa associated with the marine macroorganism Apostichopus japonica (trepang) were determined by gas-liquid chromatography and gas chromatography-mass spectrometry. In the culture liquid of S. aciculosa, prostaglandins (PG) of groups E and F were revealed by UV spectroscopy. This finding was confirmed by the presence of direct precursors of PG, polyunsaturated eicosapentaenoic and docosahexaenoic acids, in the culture liquid. The biomass of this fungus contained PG of group B.  相似文献   
84.
AIM: Evaluation of the diagnostic value of pheno- and genotypic characteristics of B. cepacia strains collection. MATERIALS AND METHODS: Phenotypic and genetic methods of identification and differentiation of 25 strains of the B. cepacia complex. RESULTS: Polyphasic taxonomic approach utilizing multiple diagnostic tests was used for accurate identification of Burkholderia species. Algorithm for identification of microorganisms from the B. cepacia complex was developed. CONCLUSION: Combined use of phenotypic and molecular genetic tests, such as recA gene PCR, is recommended for differentiation of the B. cepacia complex genomovars.  相似文献   
85.
The therapeutic efficacy of enterocin S760, a broad spectrum antimicrobial peptide produced by Enterococcus faecium LWP760 was tested on mice infected with Bacillus anthracis M-71 to induce anthrax (second Tsenkovsky's vaccine). Intraperitoneal four-, two- or one-fold administration of the peptide in a dose of 25 mg/kg for 10 days for prophylactic (1 hour after the contamination) and therapeutic (24 hours after the contamination) purposes prevented or cured the infection in 90-100% of the mice versus the 100-percent lethality in the control (untreated animals). The antimicrobial activity of enterocin S760 against B. anthracis M-71 in vivo correlated with activity in vitro. Enterocin S760 is considered a novel promising antimicrobial for the treatment of grampositive and gramnegative infections.  相似文献   
86.
The cultural, physiologo-biochemical adhesive and antagonistic properties of B. subtilis strains with good prospects for use as biotherapeutic preparations were studied. For further studies B. subtilis strain No. 1719 was chosen. In experiments on non-inbred white mice the animals were treated by the preparation Cifran used for their selective decontamination from opportunistic microflora and for the creation of the state of dysbiosis. The influence of the spore-forming microbe on the parietal microflora of the large intestine of the animals was shown. Reliable data on the changes in the number of microorganisms (CFU/ml) per 1 cm of the surface of the large intestine were established. As markers making it possible to evaluate the action of biotherapeutic and other medicinal remedies, easily determinable ratios of lac+/lac- of bacteria and Staphylococcus aureus/Staphylococcus spp. was proposed.  相似文献   
87.
We have found that intravenous administration of cannabinoid receptor (CB) agonist HU-210 (0.05 mg/kg), increases cardiac resistance against arrhythmogenic effect of epinephrine, aconitine, coronary artery occlusion and reperfusion in rats. Pretreatment with CB2-receptor antagonist, SR144528 (1 mg/kg), completely abolished the antiarrhythmic effect of HU-210. However this effect of HU-210 was not attenuated by pretreatment with CB1-receptor antagonist, SR141716A (3 mg/kg). We also found that HU-210 (0.05 mg/kg) decreased the relationship between infarction size and area of ischemia. It is concluded that CB2 receptor stimulation promotes an increase in the cardiac resistance against arrhythmogenic influences and probably increases myocardial tolerance of both ischemic and reperfusion damages in rats.  相似文献   
88.
Using a TV installation for studying the microcirculation (with 30-160-fold magnification), the density of microvascular network in the pia matter of the rat brain sensomotor cortex was determined after intracerebral transplantation of mesenchymal stem cells (MSC) or (as control) of the MSC cultivation nutrition medium, or of saline. The results have shown that intracerebral transplantation does not change density of microvascular network in the pia mater of the ipsilateral hemisphere. Transplantation of the MSC led to a 1.8-fold increase of density of the pia matter of the contralateral hemisphere as compared with control animals; the number of arterioles in the same zone was 2.5-fold higher than in intact rats.  相似文献   
89.
Transgenic mice carrying bovine satellite DNA IV were obtained. The size of the transgene integrated into the mouse genome was approximately 390 kb (about 100 transgene copies) as determined by a semiquantitative PCR. Restriction analysis with isoschizomeric restrictases HpaII and MspI, showed that the alien DNA was methylated. In the genome of a transgenic founder male, two integration sites for satellite DNA IV were revealed by in situ hybridization and in situ PCR. These sites are situated on two different chromosomes: in pericentromeric heterochromatin and within a chromosomal arm. In transgenic mice, de novo formation of heterochromatin regions (C-block and the CMA3 disk within the centromeric heterochromatin of another chromosome) was revealed by C-banding and staining with chromomycin A3. This formation is not characteristic of mice, because their chromosomes normally contain no interstitial C-blocks or sequences intensely stained by chromomycin A3.  相似文献   
90.
The investigation is aimed to study qualitative and quantitative composition of phospholipids, cholesterol content and lipids unsaturation index in plasma membranes of Guerin's carcinoma cells sensitive or resistant to doxorubicin. The comparison of infrared spectra and phospholipids unsaturation index showed that the unsaturation level of fatty acids in plasma membrane from resistant cells was lower than that from sensitive carcinoma cells. 31P-NMR spectroscopy of plasma membranes phospholipids shows the increase of phosphatidylserine and sphingomyeline content in plasma membrane isolated from resistant tumor as compared with sensitive tumor. The levels of phosphatidylcholine and phosphatidylethanolamine were equal in drug-resistant and drug-sensitive carcinoma strains. Changes in plasma membrane from resistant cells result in elevation of plasma membrane microviscosity and phosphatidylserine level increase can suggest the activation of P-glycoprotein-mediated efflux of doxorubicin.  相似文献   
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