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91.
The results of study of the antiviral activity and pharmacokinetics of phenylimide of cis-aconitic acid (PCAA) is presented. The 20% increase of the antiviral activity of PCAA incorporated into liposomes in comparison with the antiviral activity of the pure substance was shown. Liposomes with PCAA were tropic to lymphocytes and macrophages with maximum fluorescence being observed in the spleen, while empty liposomes were accumulated mainly in the liver. After the treatment with liposomal PCAA the symptoms of herpetic meningoencephalitis became less severe with 100% survival of the experimental animals. In the control group of rabbits 50% of the animals died, and in the surviving animals blindness or paralysis developed.  相似文献   
92.
A series of heteroleptic bisphthalocyaninates [(15C5)4Pc]M(Pc) ((15C5)4Pc = 2,3,9,10,16,17,24,25-tetrakis(15-crown-5)phthalocyaninate; Pc = unsubstituted phthalocyaninate; M = La, Sm, Dy, Tm) was synthesized. The raise-by-one-story method was applied in the cases of Sm, Dy and Tm complexes, whereas for the La complex we have developed a new synthetic approach. The complex [(15C5)4Pc]La(Pc) is the first representative of heteroleptic lanthanum diphthalocyaninates. Homoleptic counterparts M[(15C5)4Pc]2 and M(Pc)2, M = La, Sm, Dy, Tm have also been prepared for comparative studies. The UV-Vis spectral properties of all synthesized heteroleptic compounds were investigated and compared to those of the homoleptic unsubstituted and crown-substituted diphthalocyaninates. Cation-induced dimerisation of heteroleptic complexes was studied. The observed spectral effects were explained in terms of excitonic coupling between chromophoric molecules. The unsymmetrical distribution of electronic density over macrocyclic ligands is established.  相似文献   
93.
The three-dimensional structure of yellow fluorescent proteins zYFP538 (zFP538) from the button polyp Zoanthus sp. was determined at a resolution of 1.8 angstrom by X-ray analysis. The monomer of zYFP538 adopts a structure characteristic of the green fluorescent protein (GFP) family, a beta-barrel formed from 11 antiparallel beta segments and one internal alpha helix with a chromophore embedded into it. Like the TurboGFP, the beta-barrel of zYFP538 contains a water-filled pore leading to the chromophore Tyr67 residue, which presumably provides access of molecular oxygen necessary for the maturation process. The post-translational modification of the chromophore-forming triad Lys66-Tyr67-Gly68 results in a tricyclic structure consisting of a five-membered imidazolinone ring, a phenol ring of the Tyr67 residue, and an additional six-membered tetrahydropyridine ring. The chromophore formation is completed by cleavage of the protein backbone at the Calpha-N bond of Lys66. It was suggested that the energy conflict between the buried positive charge of the intact Lys66 side chain in the hydrophobic pocket formed by the Ile44, Leu46, Phe65, Leu204 and Leu219 side chains is the most probable trigger that induces the transformation of the bicyclic green form to the tricyclic yellow form. A stereochemical analysis of the contacting surfaces at the intratetramer interfaces helped reveal a group of conserved key residues responsible for the oligomerization. Along with others, these residues should be taken into account in designing monomeric forms suitable for practical application as markers of proteins and cell organelles.  相似文献   
94.
Plasma Physics Reports - Results of experimental studies of toroidal Alfvén eigenmodes (TAEs) in the Globus-M spherical tokamak (R = 36 cm, a = 24 cm) are reported. The experiments were...  相似文献   
95.
The three-dimensional structure of yellow fluorescent proteins zYFP538 (zFP538) from the button polyp Zoanthus sp. was determined at a resolution of 1.8 Å by X-ray analysis. The monomer of zYFP538 adopts a structure characteristic of the green fluorescent protein (GFP) family, a β-barrel formed from 11 antiparallel β segments and one internal α helix with a chromophore embedded into it. Like the TurboGFP, the β-barrel of zYFP538 contains a water-filled pore leading to the chromophore Tyr67 residue, which presumably provides access of molecular oxygen necessary for the maturation process. The post-translational modification of the chromophore-forming triad Lys66-Tyr67-Gly68 results in a tricyclic structure consisting of a five-membered imidazolinone ring, a phenol ring of the Tyr67 residue, and an additional six-membered tetrahydropyridine ring. The chromophore formation is completed by cleavage of the protein backbone at the C α -N bond of Lys66. It was suggested that the energy conflict between the buried positive charge of the intact Lys66 side chain in the hydrophobic pocket formed by the Ile44, Leu46, Phe65, Leu204 and Leu219 side chains is the most probable trigger that induces the transformation of the bicyclic green form to the tricyclic yellow form. A stereochemical analysis of the contacting surfaces at the intratetramer interfaces helped reveal a group of conserved key residues responsible for the oligomerization. Along with others, these residues should be taken into account in designing monomeric forms suitable for practical application as markers of proteins and cell organelles.  相似文献   
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The occurrence of alleles and genotypes of polymorphic region −174G>C of the gene IL6 (rs1800795) in patients of Russian ethnicity with ischemic stroke (200 cases) and in the control of the same ethnicity similar in sex and age (140 control subjects) has been analyzed. Reliable differences were revealed in the carriage frequency of allele IL6*-174G in homozygous and heterozygous form (p = 0.0029, OR = 2.9, 95% CI: 1.4–5.8), which can be considered a risk factor for the development of ischemic stroke, and in the carriage frequencies of protective genotype IL6*-174C/C (p = 0.0029, OR = 0.35, 95% CI: 0.17–0.69), respectively. After the patients and the control subjects were divided by gender character, similar differences were observed only between women with ischemic stroke and those from the control group, and after division by age, they were only revealed in groups with members older than 60 years. Complex analysis of the association of ischemic stroke with the carriage of alleles and genotypes of IL6 SNP-174G>C in combination with SNP 4266A>G (Thr312Ala) of the gene FGA (rs6050) and -249C>T of the gene FGB (rs1800788) revealed protective combinations of IL6*-174C/C + FGA*4266A and IL6*-174C/C + FGB*-249C, which are slightly more reliably associated with ischemic stroke than the one protective genotype IL6*-174C/C and have nearly the same OR value. At the same time, combinations of alternative allele IL6*-174G and the same alleles FGA*4266A or FGB*-249C were revealed that are characterized by a decrease in both the significance level and the OR value as compared with the carriage of one risk allele IL6*-174G. When there is a combined carriage of the allele IL6*-174G with the genotypes FGA*4266A/A, FGB*-249C/C or with combinations of these alleles/genotypes, the neutralizing effect is enhanced. In other words, we observed the association of IL6, FGA and FGB allele combinations with ischemic stroke in which IL6 plays the key role and FGA and FGB have a modulating function. In analyzing the association of the alleles/genotypes of three polymorphic regions with the fibrinogen level in plasma, no reliable difference was revealed.  相似文献   
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