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Necessary optimality conditions for efficient solutions of unconstrained and vector equilibrium problems with equality and inequality constraints are derived. Under assumptions on generalized convexity, necessary optimality conditions for efficient solutions become sufficient optimality conditions. Note that it is not required here that the ordering cone in the objective space has a nonempty interior. 相似文献
124.
Oncogenic MicroRNAs Biogenesis as a Drug Target: Structure–Activity Relationship Studies on New Aminoglycoside Conjugates
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125.
E. Herrmann Nguyen Thi Thu Chau O. Navratil G. Ohms L. Beyer 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract The new 1,1-disubstituted 3-diphenoxy(thio)phosphoryl-(thio)ureas, R1R2NC(X)NHP(0Ph)2, HA, with X,Y = O,S, were synthesized by addition of secondary mines to the corresponding P-iso(thio)cyanates. This reaction is reversible if X,Y = S. (PhO)2P(Y)Cl reacts with H2NC(X)NR2 in the presence of an HCl acceptor only if X,Y a 0. Side reactions are observed. Phosphorylated derivatives of biuret were isolated from such a reaction mixture. 相似文献
126.
A. F. Gogotov Do Chiem Tai L. V. Kanitskaya V. K. Stankevich 《Russian Journal of Applied Chemistry》2013,86(12):1832-1834
New approach to processing of phenols to enable their use as thermopolymerization inhibitors of unsaturated components of pyrocondensates is suggested. The method consists in a mild thermal treatment of a mixture of phenol, solvent, and kraft terpentine. A treatment of this kind results in that any (un)substituted phenol acquires inhibiting properties that compare well with those of the best phenolic inhibitors. 相似文献
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Recently, extracts from the pericarp of mangosteen, Garcinia mangostana L., exhibited various pharmacological properties such as anti-oxidative, anti-inflammatory, anti-bacterial and chemopreventive activities. Albeit it has diverse application, there is little information about its pharmacokinetic aspects. Thus, the present study was undertaken to develop the simultaneous determination of α- and γ-mangostins (α- and γ-MG), major and active compounds, from extracts for the application of pharmacokinetic studies in mice using combined liquid chromatography–tandem mass-spectrometry and microsampling systems. The intra- and inter-validation, precision, accuracy, stability, recovery and matrix effects of α- and γ-MG were conducted in mouse plasma. Based on the developed analytical methods, pharmacokinetic parameters of α- and γ-MG after intravenous and oral administration of mangosteen extract were calculated. In sample preparation steps, the biological samples were deproteinized by acetonitrile and chromatographic separation was accomplished on a C18 column. The detection was accomplished by multiple-reaction monitoring scanning after electrospray ionization source in the positive ionization mode. The optimized mass transition ion pairs (m/z) for quantitation were 411.062 → 354.900, 397.384 → 340.900, and 808.379 → 527.200 for α- and γ-MG and docetaxel (internal standard), respectively. The total run time was 5 min. The results provided a meaningful basis for the preclinical and clinical application of mangosteen extract. 相似文献
129.
Ayşegül Doğan Emirhan Nemutlu M. Aykut Özek Hakan Eroğlu Sedef Kır M. Sinan Beksaç 《Chromatographia》2013,76(21-22):1513-1519
Pregnancy alters pharmacokinetic profile of many drugs, because of altering body volume and metabolism rate. Therefore, dosage rates and concentrations of drugs must be controlled during pregnancy. Here, we identified the pharmacokinetic profile of pre-operatively given cefepime in caesarean section and gynecological operations using a simple, rapid, cost-effective and valid liquid chromatographic method. The chromatographic separation was performed using 40 mM, pH 3.2 phosphate buffer containing 6 % methanol as mobile phase at 0.30 mL min?1 flow rate. Gradient elution with methanol was applied to get shorter analysis time without any interference from plasma endogens. During analyses, temperature of column, autosampler and detector were set as 30, 10 and 40 °C, respectively. The detection wavelength was 260 nm and ceftizoxime was used as internal standard. At the optimum conditions, the cefepime analysis from plasma samples was completed in 7 min. Cefepime was extracted from plasma samples using perchloric acid with a very high recovery rate (99.3 %). The method was fully validated according to the Food and Drug Administration guidelines for bioanalytical method validation, and found to be selective, linear, repeatable, reproducible and robust. After validation studies, the method was applied to five caesarean-sectioned and four non-pregnant sectioned women treated with pre-operative, prophylactic single intravenous dose of cefepime (1 g Maxipime®) in order to determine pharmacokinetic profile of cefepime. Peak serum concentrations of cefepime in caesarean-sectioned women at the arterial port after infusion was 70.11 ± 10.74 μg mL?1. The mean elimination half-life, volume of distribution and calculated area under the concentration–time curve (AUC)0–∞ were 1.10 ± 0.23 h, 14.22 ± 2.29 L and 101.55 ± 10.99 μg h mL?1 for caesarean-sectioned women; and 1.14 ± 0.21 h, 14.76 ± 2.92 L and 104.71 ± 36.34 μg h mL?1 for non-pregnant sectioned women, respectively. The area under curve, elimination half-life, maximum plasma concentration and the mean distribution volume of cefepime were not changed in case of pregnancy. 相似文献
130.
1,3-diproyloxycalix[4]arene azacrown ether was successfully synthesized in the fixed 1,3-alternate conformation which was confirmed by a solid state structure. 相似文献