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51.
52.
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   
53.
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   
54.
Pulse electric current sintering is used to prepare a compact from resinificated hydrous silk powder. Compacts with no remnant silk powders are formed with 20 wt% added water, 20–40 MPa molding pressure, and >353 K molding temperature. The latter two are much lower than those used for conventional hot pressing. No dependence on molding pressure and temperature are found in XRD or FT‐IR analysis, except for a compact molded at 473 K, for which silk fibroin decomposition is confirmed by DSC, EGA‐MS, and molecular weight measurements. The compact's three‐point bending strength depends on the molding temperature, except for the temperature at which silk fibroin decomposes. The maximum three‐point bending strength resembles that of general‐purpose epoxy resin and is much higher than that of PLA.

  相似文献   

55.
56.
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   
57.
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   
58.
Preparation of anodes for oxygen evolution in seawater electrolysis was carried out. Manganese-molybdenum double oxides, Mn1−xMoxO2+x, prepared by anodic deposition from MnSO4-Na2MoO4 solutions showed the 100% oxygen evolution efficiency at a current density of 1000 A m−2 in 0.5 M NaCl at 30 °C and pH 12, but an increase in solution temperature resulted in dissolution of the oxides as molybdate and permanganate ions. In order to increase the stability of the electrodes at higher temperatures the addition of iron to the manganese-molybdenum oxides was performed by anodic deposition in MnSO4-Na2MoO4-FeNH4(SO4)2 solutions. The electrodes thus prepared showed the 100% oxygen evolution efficiency at 1000 A m−2 in 0.5 M NaCl at 30-90 °C, when proper amounts of molybdenum and iron were contained. The iron addition also enhanced the oxygen evolution efficiency. The electrodes were not composed of oxide mixtures but triple oxides, Mn1−xyMoxFeyO2+x−0.5y, consisting of Mn4+, Mo6+ and Fe3+. The formation of the triple oxides seemed responsible for enhancement of both oxygen evolution efficiency and stability.  相似文献   
59.
To synthesize Ti3SiC2 samples, pulse discharge sintering (PDS) technique was utilized to sinter elemental powders of Ti/Si/C with stoichiometric and off-stoichiometric ratios in a temperature range of 1200–1500 °C. The results showed that high purity Ti3SiC2 could not be obtained from the Ti/Si/C powder with molar ratio of 3:1:2, and Ti3SiC2 preferred to form at relatively low sintering temperature for a short time. When 5Ti/2Si/3C and 3Ti/1.5Si/2C powders were sintered for 15 min, the TiC content was respectively decreased to 6.4 and 10 wt.% at 1250–1300 °C. The corresponding relative density of the samples sintered from 5Ti/2Si/3C powder was calculated to be as high as 99% at the temperature above 1300 °C. It is suggested that low-temperature rapid synthesis of Ti3SiC2 would be possible through the PDS technique, provided that the composition of the starting powders should be adjusted to be off-stoichiometric ratio from 3:1:2.  相似文献   
60.
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   
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