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41.
Biological activities of the RNA replicative form of phage f2, a natural interferon inductor and poly-I -- poly-C, a synthetic polyribonucleotide complex were studied comparatively. Differences in the comparative interferonogenic and antiviral activity of the inductors were as dependent on the type of the cell system. It was shown that DEAE-dextran increased the interferon-inducing activity of RFf2 in the cell culture by 4 to 8 times. The dynamics of the interferonogenic and antiviral activity of RFf2 in the L-929 cell culture was studied. Interferon appeared in the culture fluid in 6--8 hours and reached its maximum titers (128 IU50/ml) by the 24th hour, the maximum protection of the cells being also developed by the 12th--24th hour, reaching on an average 51 g PFU/ml. It was shown in the experiments with green marmosets that administration of RFf2 in the form of aerosol in a dose of 2.3 mg/kg induced interferon production in the blood serum the titers of which amounted to 80--160 IU50/ml 24 hours after the administration.  相似文献   
42.
The summarized data on the biological activity of acridoneacetic acid, a low-molecular interferon inducer are presented: the amount and type of induced interferon, producer cells, interaction with viruses; the antiviral, antitumoral and anti-inflammatory activity of the preparation has been demonstrated. The specific features of interferon induction by virus (a biological inducer), in contrast to acridoneacetic acid (a chemical inducer) have been noted. The possible mechanisms of interferon induction by low-molecular interferonogen are considered. A number of interferonogens, salts of acridoneacetic acid, proposed as medicinal preparations are considered. The results of the clinical use of Cycloferon, a medicinal form of acridoneacetic acid, are presented.  相似文献   
43.
Isopentenyl diphosphate isomerase (IPP isomerase) in many organisms and in plastids is central to isoprenoid synthesis and involves the conversion between IPP and dimethylallyl diphosphate (DMAPP). It is shown that Synechocystis PCC6803 is deficient in IPP isomerase activity, consistent with the absence in its genome of an obvious homologue for the enzyme. Incorporation of [1-(14)C]IPP in cell extracts, primarily into C(20), occurs only upon priming with DMAPP in Synechocystis PCC6803 and in Synechococcus PCC7942. Isoprenoid synthesis in these cyanobacteria does not appear to involve interconversion of IPP and DMAPP, raising the possibility that they are not within the plastid evolutionary lineage.  相似文献   
44.
The occurrence rate of HGV/GBV-C RNA, genotypic variety of isolates and various risk factors of infection with HGV/GBV-C were evaluated in 500 patients of the narcological dispensary of Novosibirsk. The occurrence rate of HGV/GBV-C RNA among all examined blood sera was 33.6%. At the same time in blood sera with HCV markers the occurrence rate of HGV/ GBV-C was 42.9% and in sera with negative results for markers HCV--25%. For gene typing of obtained isolates the direct sequencing of the amplification products of fragment NS3B and the phylogenetic analysis of the sequences thus obtained were used. Almost all isolates subjected to gene typing belonged to genotype 2, widespread in Europe, and only 1 isolate was classified with genotype 4. Statistically significant (p<0.05) risk of HGV/GBV-C infection among the examined subjects was linked with the intravenous use of drugs (OR 2.15), risky sexual behavior (OR 1.8) and the presence of virus hepatitis C (OR 2.26).  相似文献   
45.
Interferon-inducing activity of polyanions (dextran Sulfate, native DNA, polyphosphate, polypentose, polyanetole sulfate, heparin) was studied. Dextran sulfate applied parenterally and enterally was found to be capable of inducing endogenous interferon production in white mice. The maximal titers of interferon (160 units/ml) were seen in the blood serum of mice upon administering the preparation in a dose of 20 mg/kg body mass. No substantial differences were discovered in the time course of interferon production whatever the route of administration.  相似文献   
46.
47.
It has been shown that the immunostimulant inosiplex (IP) is capable of inducing interferon production in mice and of stimulating interferon induction by high-molecular inducers. The combined use of IP and poly (G)-poly (C) or dsRNA (RFf2) leads to a longer interferon circulation in the blood. All the combination schemes ensuring the effect of interferon production prolongation were tested for anti-viral activity. The prophylactic administration of the drugs permitted the attainment in mice of the increased resistance to experimental influenza.  相似文献   
48.
The Russian Federation prohibited the distribution of herbal mixtures with synthetic aminoalkylindoles JWH-018 and JWH-073, agonist cannabinoid receptors, on January 22, 2010. The lack or low content of their native compounds in urine requires detailed identification of their metabolites, which are excreted with urine and are present in blood. Using gas and liquid chromatography-mass spectrometry, we identified a series of metabolites in urine samples from humans and rats that were products of the following reactions: (a) mono- and dihydroxylation of the parent compounds with hydroxyl groups located at aromatic and aliphatic residues, (b) carboxylation, (c) N-dealkylation and (d) N-dealkylation and hydroxylation. The prevailing urinary metabolites in humans are monohydroxylated forms, while N-dealkylated and N-dealkyl monohydroxylated forms are found in rats. Twenty-six samples of herbal smoking mixtures with JWH-018, purchased in Russia, were analysed.  相似文献   
49.
Microbiology - Biogenic sulfide production in oilfields results in lower quality of oil and gas and in corrosion of oil-producing equipment. Bactericidal agents are not used at the Karazhanbas...  相似文献   
50.
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