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61.
A new and promising nitrosyl ruthenium complex, [Ru(NO)(bdqi-COOH)(terpy)](PF6)3, bdqi-COOH is 3,4-diiminebenzoic acid and terpy is 2,2′-terpyridine, has been synthesized as a NO donor agent. The procedure used for [Ru(NO)(bdqi-COOH)(terpy)](PF6)3 synthesis has, apparently, yielded the formation of two isomers in which the ligand bdqi-COOH appears to be coordinated in its reduced form (bdcat-COOH), which could have differences in their pharmacological properties. Therefore, it was intended to separate the two possible isomers by high-performance liquid chromatography (HPLC) and to characterize them by high resolution mass spectrometry (QTOF MS) and by magnetic nuclear resonance spectroscopy (NMR). The results obtained by MS showed that the ESI-MS mass spectra of both HPLC column fractions, e.g. peak 1 and peak 2, are essentially equal, showing that both isomers display nearly identical gas-phase behavior with clusters of isotopologue ions centered at m/z 573, m/z 543 and m/z 513. Regarding the NMR analysis, the results showed that the positional isomerism is located in the bdqi-COOH ligand. From the observed results it can be concluded that the synthesis procedure that has been used results in the formation of two [Ru(terpy)(bdqi-COOH)NO](PF6)3 isomers.  相似文献   
62.
The impacts of New Hope, a program to increase parent employment and reduce poverty, were measured 5 years after parents were randomly assigned to program or control groups. New Hope had positive effects on children's school achievement, motivation, and social behavior, primarily for boys, across the age range 6-16. In comparison to impacts measured 2 years after program onset, effects on achievement were robust, but effects on social behavior were reduced. The program produced improvements in family income and use of organized child care and activity settings, suggesting possible pathways by which the New Hope package of policies influenced children's behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
63.
Summary  Various diameters of polyaniline (PANI) nanofibers were easily made by varying the sweep rate in the electrochemical polymerization of the aniline monomer. At a sweep rate of 5 mV/s, the PANI nanofibers have an average diameter of 450 nm with a median of 440 nm. The fibers are short, on the order of a few microns in length, and exhibit a branched geometry. Increasing the sweep rate to 50 mV/s produced longer nanofibers with a smaller average diameter of 200 nm. Nanofibers synthesized at 100 mV/s were noted to be smaller with an average and median diameter of 100 nm. These results illustrate the ease in which the morphology of nanostructured PANI can be altered and indicate that the method has the potential to create multi-diameter fibers or mixed-morphology materials.  相似文献   
64.
Extracellular concentrations of dopamine (DA) and its metabolites dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) were examined concurrently, using in vivo microdialysis, in the nucleus accumbens and dorsal striatum of sexually active male rats during tests of locomotor activity, exposure to a novel chamber, exposure to sex odors, the presentation of a sexually receptive female, and copulation. DA increased significantly in the nucleus accumbens when the males were presented with a sexually receptive female behind a screen and increased further during copulation. Although DA also increased significantly in the dorsal striatum during copulation, the magnitude of the effect was significantly lower than that observed in the nucleus accumbens. In contrast, forced locomotion on a rotating drum, exposure to a novel chamber, and exposure to sex odors did not increase DA significantly in either region. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
65.
Saturated solutions rerely form when the anhydrous constituents of aluminous and portland cement are stirred in water or in lime solutions of increasing concentrations. Apart from monocalcium aluminate, concentration of ions in solution cannot exceed maximum supersaturation with respect to the hydrate most likely to precipitate. The present work shows such a behavior for β-C2S suspended in water and in lime solutions at low concentration. In more concentrated lime solutions, a short lifetime saturation state with respect to β-C2S seems to be reached.  相似文献   
66.
In 3 experiments the authors investigate how errors in perception produce errors in drawings. In Experiment 1, when Shepard stimuli were shown as a pair of tables, participants made severe errors in trying to adjust 1 part of the stimulus to match the other. When the table legs were removed, revealing a pair of parallelograms with minimal perspective cues, the illusion was weaker. The authors predicted that participants would err when drawing the table but not the parallelogram stimuli. The results of Experiment 2 support the prediction and establish a direct link between degree of perceptual distortion of the table stimuli and the severity of error in drawing. When drawing only the right-hand part of the figure, participants also erred to a greater degree in drawing the table than the parallelogram (Experiment 3). Collectively, the results suggest that perceptual distortion is linked with errors in drawing the table stimuli. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
67.
Drug-induced spoliation of hydrogels as contact lenses or as implants in the anterior eye is a frequent occurrence in clinical practice. This study explores the capacity of three commercial multipurpose solutions for contact lens care to reduce the spoliation of poly(2-hydroxyethyl methacrylate) (PHEMA) specimens exposed to a simulated aqueous humour formulation and to three topical drugs commonly administered after insertion of artificial corneas (Predsol, Optimol and Depo-Ralovera). ReNu MultiPlus (Bausch & Lomb), Complete Blink-N-Cleantrade mark Lens Drops (Allergan) and Complete Protein Remover Tablets dissolved in Complete ComfortPLUS (both from Allergan) were evaluated. All multipurpose solutions were able to dislodge passively the deposits formed on hydrogels in the simulated aqueous and in the presence of Predsol and Optimol, but none were effective against the deposits induced by Depo-Ralovera. A reduction of the calcium content in deposits caused by Predsol and Optimol was confirmed after treatment with the protein remover preparation, while the other multipurpose solutions caused the complete removal of the deposits. In experiments designed to evaluate the preventive action of the multipurpose solutions, no such effects were observed regardless of the drug involved. The prospect of using multipurpose solutions as eye drops following implantation of a hydrogel artificial cornea is a valid alternative for reducing device spoliation, however it appears to depend on the nature of the postoperative medication.  相似文献   
68.
Prenylation is a post‐translational modification wherein an isoprenoid group is attached to a protein substrate by a protein prenyltransferase. Hundreds of peptide sequences are in vitro substrates for protein farnesyltransferase (FTase), but it remains unknown which of these sequences can successfully compete for in vivo prenylation. Translating in vitro studies to predict in vivo protein farnesylation requires determining the minimum reactivity needed for modification by FTase within the cell. Towards this goal, we developed a reporter protein series spanning several orders of magnitude in FTase reactivity as a calibrated sensor for endogenous FTase activity. Our approach provides a minimally invasive method to monitor changes in cellular FTase activity in response to environmental or genetic factors. Determining the reactivity “threshold” for in vivo prenylation will help define the prenylated proteome and identify prenylation‐dependent pathways for therapeutic targeting.  相似文献   
69.
70.
The focus of the world's attention on environmental issues in recent years has stimulated responses in many countries which have led to a closer examination of energy conservation strategies for conventional fossil fuels. Buildings are important consumers of energy and thus important contributors to emissions of greenhouse gases into the global atmosphere. The development and adoption of suitable renewable energy technologies has an important role; a review of options indicates benefits and some problems. There are two key-elements to the fulfilling of renewable energy technology potential within the field of building design; firstly the instilling of appropriate skills and attitudes in building design professionals, and secondly the provision of the opportunity for such people to demonstrate their skills. This second element may only be created when the population at large, and clients commissioning building design in particular, become more aware of what can be achieved and what resources are required.  相似文献   
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