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61.
Although antidepressants are generally effective in the treatment of major depressive disorder (MDD), it can still take weeks before patients feel the full antidepressant effects. Despite the efficacy of standard treatments, approximately two-thirds of patients with MDD fail to respond to pharmacotherapy. Therefore, the identification of blood biomarkers that can predict the treatment response to antidepressants would be highly useful in order to improve this situation. This article discusses inflammatory molecules as predictive biomarkers for antidepressant responses to several classes of antidepressants, including the N-methyl-d-aspartate (NMDA) receptor antagonist ketamine.  相似文献   
62.
We developed a water-in-oil-in-water (W/O/W)-type multiple emulsion of a new tacrolimus formulation. A potential approach to avoid the complications of systemic immunosuppression and simultaneously enhance immunosuppressive efficacy is to deliver immunosuppressive agents locally to the site of the target organs. The W/O/W emulsion is dispersed oil drops containing smaller water droplets that allow the delivery of drugs preferentially to the reticuloendothelial system (RES). Since the liver and the spleen are primary components of the RES, and the brain and the kidney have a poor RES, we hypothesized that a W/O/W emulsion of tacrolimus would prossess the pharmacokinetic benefits of local immunosuppression. We evaluated this hypothesis in a rat model. The tacrolimus levels of whole blood, the liver, spleen, brain, and kidney in rats given intravenous emulsions of tacrolimus (W/O/W group) were compared with a group administered tacrolimus alone (T group). There were no significant differences between the pharmacokinetic parameters of W/O/W group and T group based on whole blood data. However, the W/O/W group had significantly decreased tacrolimus levels in the brain and kidney, and significantly increased levels in the liver and spleen compared with the T group. These data suggest that the W/O/W emulsion is applicable as an intravenous drug carrier for local immunosuppression.  相似文献   
63.
Three-phase equilibrium (pressure–temperature) relation of hydrate+aqueous+fluid phases for the hydrogen (H2)+tetra-n-butyl phosphonium bromide (TBPB)+water ternary system was investigated in a temperature range of 281.90–295.94 K and a pressure range up to 170 MPa. The behavior of the three-phase coexisting curve indicates no structural transition in the present experimental region. The Raman spectra obtained in the H2+TBPB mixed semi-clathrate hydrate crystal reveal that H2 molecule occupies only small cage compartmentally and the TBPB molecule is encaged with a set of other large cages.  相似文献   
64.
Carbon-containing refractories are widely used in the steelmaking process due to their outstanding properties and, in order to improve their oxidation resistance, the so-called antioxidants have often been used. Al4SiC4 is pointed out as a novel additive that presents suitable properties such as Al, but without its drawbacks. Therefore, the effect of Al4SiC4 addition to Al2O3SiCSiO2C castables designed for lining blast furnace troughs was investigated in this work. Apparent porosity, oxidation, thermogravimetric, X-ray diffraction, hot elastic modulus tests and thermodynamic calculations were carried out in order to better understand the antioxidant effects and reaction mechanisms. Additionally, the collected results were compared with those from the compositions containing other commonly used antioxidants (Si, B4C and sodium borosilicate glass). The performance of the novel additive proved to be limited as most of the carbon source used reacted earlier than the Al4SiC4 action. As a consequence, intense carbon oxidation, along with the thermal expansion mismatch among the phases during the cooling step, intensified the deterioration of the evaluated refractory material.  相似文献   
65.
Reforming of CH4 with CO2 proceeds at 400 °C over a catalyst consisting of ruthenium metal and CeO2 highly dispersed on mordenite. The catalyst, Ru-CeO2/MZ, is highly active for the reforming of CH4 under the conditions at which a carbon formation reaction is thermodynamically apt to take place. The reforming selectively forms H2 and CO. An increase in the weight of the catalyst resulting from carbon deposits was scarcely observed. IR spectra for the catalyst indicate that the reforming proceeds via the formation of the intermediate species such as Ru-CO and Ru-CHx on the surface of ruthenium. The data of H2 adsorption support the idea that ruthenium is highly dispersed in Ru-CeO2/MZ.  相似文献   
66.
The alumina–carbon composite fibers were obtained from poly[(acyloxy)aloxane] (PAA) with 3-ethoxypropanoic (EPA) and m-anisic acids (m-AA) legands. This preceramic polymer can be dissolved in p-xylene-methanol-EPA mixed solvent, and the concentrated solution exhibited an excellent spinnability. During the pyrolysis and sintering processes, aliphatic carboxylate in the side groups was easily decomposed and eliminated. The aromatic carboxylate, however, seems to be converted and migrated to a carbon domain in the alumina matrix into which aloxane repetition was converted. The fibers pyrolyzed up to 800 and 1000°C have electrical conductivities that monotonically increase with increasing temperature. The fiber pyrolyzed up to 1200°C showed the electrical conductivity in a rather complicated manner.  相似文献   
67.
Hydrodechlorination of chlorobenzenes on platinum (Pt)-supported γ-alumina and alumina Lewis superacid (AmLSA) catalysts was carried out at room temperature and ambient pressure using a fixed bed flow reactor and a semi-batch reactor. Both the catalysts indicated good activity for the hydrodechlorination, but the former was superior to the latter. The hydrodechlorinations of reactants C6H6−xClx (x=1, 2, 3) proceeded step-wisely to benzene and then cyclohexane via C6H6−yCly (y=x−1). The reactions seem to be promoted by the contribution of spillover hydrogen formed on the Pt-supported catalysts. The catalysts deactivated with reaction time and the amount of chlorine that accumulated on the Pt-supported γ-alumina catalyst in the hydrodechlorination of 1,4-dichlorobenzene for 3 h was near to that estimated from the converted reactant molecules. When the deactivated catalysts were treated in a stream of hydrogen above 503 K, the original activity was completely restored, but the deactivation phenomenon with reaction time was observed again.  相似文献   
68.
Consolidation-sedimentation behaviors of consolidated sediment under action of gravity were investigated using highly concentrated suspension of titanium dioxide particles under conditions of various pHs, initial heights, and initial concentrations. The average consolidation ratio of the consolidated sediment was analyzed on the basis of the simplified analytical solution obtained using the modified Terzaghi's model under the moving Lagrangian coordinate system. Although the solution pH strongly affects consolidation-sedimentation behaviors, the modified average consolidation coefficient was little influenced by the solution pH. Also, the consolidation coefficient increased in almost direct proportion to the total volume of solids per unit cross-sectional area, which changes the driving force of consolidation-sedimentation due to the overlying weight of the solid particles. The variations with time of the height of the consolidated sediment were adequately described using the analytical solution describing the average consolidation ratio with the aid of the relation that the equilibrium height was represented by a power function of the total volume of solids for a specified pH.  相似文献   
69.
Direct synthesis of H2O2 acid solutions was studied using a gas-diffusion cathode prepared from activated carbon (AC), vapor-growing-carbon-fiber (VGCF) and poly-tetra-fluoro-ethylene (PTFE) powders, with a new H2/O2 fuel cell reactor. O2 reduction to H2O2 was remarkably enhanced at the three-phase boundary (O2(g)-electrode(s)-acid(l)) at the [AC + VGCF] cathode. Fast diffusion processes of O2 to the active surface and of H2O2 to the bulk acid solutions were essential for H2O2 accumulation. Synergy of AC and VGCF was observed for the H2O2 formation. RRDE and cyclic voltammetry studies indicated that the surface of AC functioned as the active phase for O2 reduction to HO2, and VGCF functioned as an electron conductor and a promoter to convert HO2 to H2O2. A maximum H2O2 concentration of 353 mM (1.2 wt%) was accomplished under short-circuit conditions (current density 12.7 mA cm−2, current efficiency 40.1%, geometric area of cathode 1.3 cm2, reaction time 6 h).  相似文献   
70.
A magnetic field-assisted finishing process has been studied for high-aspect-ratio ion-etched silicon curvilinear micropore structures, which have potential application as mirrors for satellite-borne X-ray telescopes. The micropore sidewalls act as X-ray focusing mirrors, and lead to reductions in the mass-to-effective-area ratio of 10-1000 times, compared to traditional X-ray telescopes. This paper describes the processing principle for the surface finishing of the sidewalls of micropore structures (10, 20 μm and depth: 300 μm (aspect ratio ≈ 15, 30)), and the feasibility of achieving roughness ∼4 nm rms and improving the X-ray reflectivity of micropore sidewall surface are demonstrated.  相似文献   
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