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排序方式: 共有1007条查询结果,搜索用时 15 毫秒
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Zarnowski R Jaromin A Certik M Czabany T Fontaine J Jakubik T Iqbal MC Grandmougin-Ferjani A Kozubek A Pietr SJ 《Zeitschrift für Naturforschung. C, Journal of biosciences》2004,59(5-6):321-326
The oil of Adenanthera pavonina L. seeds was analysed by chromatographic and instrumental means. The oil was found to be rich in neutral lipids (86.2%), and low in polar lipids (13.8%). The neutral lipids consisted mainly of triacylglycerols (64.2%). Unsaturated fatty acids were found as high as 71%, while the percentage of saturated fatty acids was only 29%. GC and GC/MS analyses revealed linoleic, oleic and lignocerotic acid to be predominant among all fatty acids in the A. pavonina oil, whereas stigmasterol was the major steroid identified within this study. Subsequently, the oil was used for preparation of submicron oil-in-water (o/w) lipid emulsions. Lipid emulsions were formulated by using soybean lecithin (SL) to investigate their particle size, Zeta potential and stability at the different oil and SL ratios. The results obtained indicate possible applications of the tested oil in pharmaceutical and medical fields as drug and cosmetic active ingredient carriers. 相似文献
44.
Pathogenicity islands, specialized secretion systems, virulence plasmids, fimbriae, pili, adhesins, and toxins are all classical bacterial virulence factors. However, many of these factors, though widespread among bacterial pathogens, are not necessarily found among bacteria that colonize eukaryotic cells in a pathogenic/symbiotic relationship. Bacteria that form these relationships have developed other strategies to infect and grow in their hosts. This is particularly true for Brucella and other members of the class Proteobacteria. Thus far the identification of virulence factors for Brucella has been largely dependent on large-scale screens and testing in model systems. The genomes of the facultative intracellular pathogens Brucella melitensis and Brucella suis were sequenced recently. This has identified several more potential virulence factors for Brucella that were not found in large screens. Here, we present an overall view of Brucella virulence by compiling virulence data from the study of 184 attenuated mutants. 相似文献
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Djinović V Momcilović M Grgurić-Sipka S Trajković V Mostarica Stojković M Miljković D Sabo T 《Journal of inorganic biochemistry》2004,98(12):2168-2173
A novel class of ruthenium (III) complexes of formulas K[Ru(sar)2Cl2].12H2O and K2[Ru(dmgly)Cl4].2H2O, containing bidentate chelates N-methylglycine (sarcosine, sar) or N,N-dimethylglycine (dmgly) and additional chloro ligands were synthesized. The complexes have been obtained by direct reaction of ruthenium(III) chloride with corresponding bidentate ligand followed by addition of base (KOH). These new complexes were characterized by elemental analysis, IR and electronic absorption spectroscopy. As astrocytomas, the most common of all brain tumors, are still very difficult to treat, we examined the influence of newly synthesized ruthenium-based complexes, as well as the earlier synthesized analogue platinum(IV) complexes [Pt(dmgly)2Cl2], [Pt(sar)2Br2] and [Pt(dmgly)2Br2], on rat astrocytoma C6 cells in vitro. Among these complexes only K2[Ru(dmgly)Cl4].2H2O and [Pt(dmgly)2Br2] markedly inhibited the viability of non-confluent C6 cells. Furthermore, only complex K2[Ru(dmgly)Cl4].2H2O was able to reduce viability in confluent C6 cultures. Importantly, this complex was not toxic to primary rat astrocytes or macrophages. Having in mind that appropriate chemotherapy should be effective against tumor cells without harming normal tissues, complex K2[Ru(dmgly)Cl4].2H2O could be a promising agent for developing therapeutics against astrocytomas. 相似文献
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Pituitary adenylate cyclase activating polypeptide (PACAP) has been shown to influence nervous system development. The aim of the present study was to investigate the effects of in ovo treatment with the PACAP antagonist PACAP6-38 during embryonic life (E8 and E16) on motor activity and social behavior in chicken. Our results showed that a single injection of PACAP6-38 during the first half of embryonic life caused subtle transient changes in general behavior and motor control when compared to saline-treated controls. Increased activity and reduced anxiety were observed also in a novel environment at 2 days after hatching. However, most of these behavioral differences disappeared by 2 weeks. PACAP6-38-treatment during the first half of embryonic life resulted in markedly reduced social behavior, which was still present at 2 weeks of age. Treatment during the second half of embryonic life resulted in no behavioral differences between control and PACAP6-38-treated chicken. PACAP content in different brain areas was not different between control and PACAP6-38-treated chicken at 5 days or 3 weeks of age, but it decreased significantly with age in both groups. In summary, our results show that PACAP6-38 treatment at E8 caused transient changes in motor behavior, and long-lasting reduction in social behavior. 相似文献
47.
The mechanisms involved in the mediation of the inhibitory effects of ethanol on gastric emptying were studied in adult male rats. The gastric emptying was determined by measuring the amount of phenol red recovered from the stomach after intragastric administration. Intragastric administration of a 2.5 g kg(-1) body weight dose of ethanol resulted in inhibition of the gastric emptying. Prior intraperitoneal treatment with lorglumide (CR-1409), a selective CCK-A receptor antagonist, abolished the inhibitory effect of ethanol on the gastric emptying. This observation furnishes evidence indicative of the involvement of type A CCK receptors in the mediation of the inhibitory effect of large doses of ethanol on the gastric emptying. 相似文献
48.
Forgács E Cserháti T Miksik I Echardt A Deyl Z 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2004,800(1-2):259-262
The retention time of 22 barbituric acid derivatives was measured on a narrow-bore porous graphitized carbon (PGC) column using water-dioxane mixtures as mobile phases. The capacity factor (k), theoretical plate number (N), and asymmetry factor (AF) were calculated for each solute in each mobile phase. The relationships between chromatographic characteristics and physicochemical parameters of solutes were elucidated by stepwise regression analysis (SRA). SRA indicated that the binding of barbiturates to the PGC surface is of mixed character electrostatic and apolar interactive forces are equally involved. Sterical correspondence between the surface of the stationary phase and the solutes also exert a significant influence on the retention behavior. 相似文献
49.
Mikó T Ligneau X Pertz HH Arrang JM Ganellin CR Schwartz JC Schunack W Stark H 《Bioorganic & medicinal chemistry》2004,12(10):2727-2736
Recent bioisoteric replacements in histamine H3 receptor ligands with an exchange of the imidazole moiety by a piperidino group as well as of the trimethylene chain in 4-((3-phenoxy)propyl)-lH-imidazole derivatives (proxifan class) by an alpha,alpha'-xylendiyl linker represents the starting point in the development of 1-(4-(phenoxymethyl)benzyl)piperidines as a new class of nonimidazole histamine H3 receptor antagonists. According to different strategies in optimization of imidazole-containing antagonists the central benzyl phenyl ether moiety was replaced by numerous other polar functionalities. Additionally, the ortho- and meta-analogues of the lead were synthesized to determine the influence of the position of the piperidinomethyl substituent. The new compounds were tested in an in vitro binding assay for their affinities for cloned human H3 receptors stably expressed in CHO-K1 cells and for their oral in vivo potencies brain in a functional screening assay in the brain of mice. Additionally, activities of selected compounds were determined in the guinea-pig ileum functional test model. In contrast to the analogues ortho-substituted compounds all other compounds maintained respectable affinities for the human H3 receptor (-log Ki values 6.3-7.5). Despite the results from other classes of compounds the 4-methyl substituted derivatives generally displayed higher affinities than the corresponding 4-chloro substituted compounds. In vivo only the inverse phenyl benzyl ether (3) showed worthwhile antagonist potencies. 相似文献
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