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101.
102.
M Tanaka M Takahashi E Kuwahara O Koyama K Ohkubo T Yotsuyanagi 《Chemical & pharmaceutical bulletin》1992,40(6):1559-1562
The effects of dipotassium glycyrrhizinate (GLYK) on the dissolution behavior and bioavailability of amphotericin B (AMB) were investigated. The mixtures of AMB and GLYK were prepared at different molar ratios by lyophilization. Lyophilization resulted in amorphous AMB either alone or in the mixture. Dissolution rates of AMB of the mixtures were markedly faster than that of lyophilized AMB alone, which was followed by a decrease of dissolution. The initially-enhanced dissolution rate was likely to be due to the improvement of surface wettability of drug particles with GLYK rather than the amorphous state of AMB. A phase solubility study of AMB with GLYK indicated that the increasing solubility was caused by micellar solubilization. The in vitro release rate of AMB from suppositories containing the lyophilized mixtures was significantly accelerated by increasing the amount of GLYK. The rectal absorption of AMB from suppositories containing either the drug alone, a physical mixture or a lyophilized mixture was studied using rabbits. The absorption of the mixture (AMB/GLYK = 1/9) was about 35 times greater in the area under the serum concentration-time curve (0-24 h) than that of lyophilized AMB alone. These results suggest that GLYK is useful for improving the dissolution property of AMB and the bioavailability of the drug incorporated in suppositories. 相似文献
103.
104.
In the (6Li,d) reaction on36Ar, the strongly excited seventeen levels were observed at excitation energies above 11 MeV in40Ca. On the basis of the result of the DWBA analysis, these levels may correspond to the members of the higher nodal α-clusterK n =O+ band with prinicpal quantum numberN=14. 相似文献
105.
A sealed tube dry combustion method that is simple, accurate, and precise for ultramicro determination of halogens in organic compounds has been developed. Samples below 1 mg are heated at 580 °C for 1 h in an electric furnace. After the combustion and absorption of the gaseous halogen, the interior of the tube is rinsed. Subsequent titration is carried out potentiometrically with silver nitrate and yielded standard deviations of 0.21% for chlorine, 0.17% for bromine, and 0.25% for iodine. 相似文献
106.
The energy spectrum and α-spectroscopic factors of40Ca are calculated by using an α+36Ar orthogonality condition model. Overall agreement is obtained with the experimental data. The model successfully produces the parity-doubletK π=O + and O? α+36Ar cluster bands. It is shown that the coexistence and interference of α-cluster states and shell-model states are indispensable to understand the structure of40Ca. 相似文献
107.
W. Sato H. Ueno A. Taniguchi Y. Itsuki Y. Kasamatsu A. Shinohara K. Asahi Y. Ohkubo 《Journal of Radioanalytical and Nuclear Chemistry》2007,272(3):665-668
The time-differential perturbed angular correlation (TDPAC) method was applied to a study on the behavior of 140Ce atoms implanted in highly oriented pyrolytic graphite (HOPG). Exponential-type gradual attenuation of the directional anisotropy
of the relevant γ-ray cascade was observed in the perturbation patterns. From temperature dependence of the relaxation rate,
a thermally activated dynamic motion of the probe atoms was suggested. 相似文献
108.
Shuichi Ban Yoshiki Takano Naoki Ohkubo Hisanobu Hoya Yumiko Takahashi Kouichi Takase Kazuko Sekizawa 《Hyperfine Interactions》2005,165(1-4):95-99
The transition metal phosphorus trichalcogenides MnPS3 and the FePS3 are CdCl2 type layered compounds, where the transition metal ions form a hexagonal lattice. While these compounds order anti-ferromagnetically at low temperature, the magnetic structures are different. We have reported that these mixtures Mn0.5Fe0.5PS3 is a spin glass with a glass transition temperature T g=33.7 K. Then, in this work, we report that the results of the temperature variation of the 57Fe Mössbauer spectra of FePS3 and Mn0.5Fe0.5PS3, in detail. In the anti-ferromagnetic state of FePS3, the hyperfine magnetic field H int increases with decreasing temperature and the Isomer shift I. S. increases slightly with decreasing temperature. However in Mn0.5Fe0.5PS3, the two broadened peaks are observed and the two peaks became a single peak with decreasing temperature at about 50.0 K, which is higher than T g=33.7 K. In the spin glass Mn0.5Fe0.5PS3, the Mössbauer spectra suggest that the magnetic interactions exist far above T g. 相似文献
109.
Manabu Kiguchi Tatsuya Konishi Shinichi Miura Kei Murakoshi 《Physica E: Low-dimensional Systems and Nanostructures》2005,29(3-4):530
We have mechanically fabricated Ni and Cu nano-constrictions in solution to study their quantized conductance behavior under electrochemical potential control. Conductance quantization was observed at both metals in solution at room temperature for the first time. The conductance of Cu nano-constriction was quantized in units of G0(=2e2/h). A sharp 1G0 peak was observed in the conductance histogram. For Ni, a rather broad peak at 1–1.5G0 was observed in the histogram. The conductance quantization behavior was discussed by comparing previously documented results of nano-constrictions fabricated in air or ultra-high vacuum conditions, with those fabricated in solution. 相似文献
110.
It is suggested that weak coupling picture for theα-cluster states holds not only in the44Ti~40Ca region but also in the upper part of thesd-shell region. To confirm this experimentally, theα-clustering aspects of38Ar is investigated. 相似文献