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排序方式: 共有122条查询结果,搜索用时 15 毫秒
51.
Susumu Hama Naoko Kirimura Aki Obara Hirokatsu Takatsu Kentaro Kogure 《Molecules (Basel, Switzerland)》2022,27(4)
Anti-rheumatoid arthritis (RA) effects of α-tocopherol (α-T) have been shown in human patients in a double-blind trial. However, the effects of α-T and its derivatives on fibroblast-like synoviocytes (FLS) during the pathogenesis of RA remain unclear. In the present study, we compared the expression levels of genes related to RA progression in FLS treated with α-T, succinic ester of α-T (TS), and phosphate ester of α-T (TP), as determined via RT-PCR. The mRNA levels of interleukin (IL)-6, tumor necrosis factor-α (TNF-α), matrix metalloproteinase (MMP)-3, and MMP-13 were reduced by treatment with TP without cytotoxicity, while α-T and TS did not show such effects. Furthermore, intraperitoneal injection of TP ameliorated the edema of the foot and joint and improved the arthritis score in laminarin-induced RA model mice. Therefore, TP exerted anti-RA effects through by inhibiting RA-related gene expression. 相似文献
52.
Picosecond photoconductivity in low-temperature-grown GaAs (LT GaAs) has been used to provide temporal resolution both in rigid probes and in scanning force microscope probes. This article reviews the fabrication and use of such probes. 2.5 ps temporal resolution and few microvolts sensitivity are obtained at arbitrary points on circuits with a spatial definition of 100 nm. Rigid probes are tested in application to analogue and digital circuits. As an alternative to electron beam testing, scanning force probes are applied toin situ imaging and waveform measurement. Finally, the use of time-resolved waveform analysis with scanning-force microscopy probes with semiconductor laser sources is demonstrated. 相似文献
53.
We investigate several fluctuation effects in high-energy hadronic and nuclear collisions through the analysis of different
observables. To introduce fluctuations in the initial stage of collisions, we use the interacting gluon model (IGM) modified
by the inclusion of the impact parameter. The inelasticity and leading-particle distributions follow directly from this model.
The fluctuation effects on rapidity distributions are then studied using Landau's hydrodynamic model in one dimension. To
investigage further the effects of the multiplicity fluctuation, we use the longitudinal phase-space model, with the multiplicity
distribution calculated within the hydrodynamic model, and the initial conditions given by the IGM. Forward-backward correlation
is obtained in this way. 相似文献
54.
Francis R. Hama 《Fluid Dynamics Research》1988,3(1-4):149-150
This is my personal account of the birth of the localized induction approximation for the self-induced velocity of a vortex filament, which is finding some interesting applications. 相似文献
55.
We have conducted a series of basic studies about Centocor's CA125 RIA Kit, especially for the conditions of the incubation. The standard curve and the outcome of recovery test gained through the standard method and the shortened method are quite decent. As for the incubation time, it took longer than 20 hours and 6-18 hours inthe standard method and shortened one respectively. As our conclusion, these results suggest that the shortened method can be adopted as a practical one as well as the standard method, provided that careful attention is paid to several peripheral conditions in the assay. 相似文献
56.
The molecular motion of low molecular weight polychlorotrifluroethylene of different molecular weights between 500 and 1300 was investigated by means of broad-line nuclear magnetic resonance measurements. The line width and second moment of the resonant absorption lines were obtained at temperatures from 77 to 300°K. The line narrowing for low molecular weight samples takes place in one step. In samples higher than 900 in molecular weight, however, there appears to be a glass transition process, and the line narrowing tends to occur in three steps. The line narrowing due to local molecular motion becomes observable with increasing molecular weight. 相似文献
57.
The phase behavior of binary systems composed of water and nonionic surfactants were investigated. The nonionic surfactants studied were the methoxypolyoxyethylene dodecanoates (R11COO(EO)
n
CH3,n=4.9, 6.1, 7.3, 9.3, and 12.8, wheren is the average number of oxyethylene units).The phase behaviors of R11COO(EO)
n
CH3 were compared with those of the polyoxyethylene dodecyl ethers (R12O(EO)
p
H) and polyoxyethylene methyl dodecyl ethers (R12O(EO)
q
CH3) which have been previously reported. It was found that the R11COO(EO)
n
CH3s have lower cloud points and lower upper limit temperatures for the existence of the mesophase as compared to the other two types. A R11COO(EO)12.8CH3/water system had favorable solution properties for practical use, such as a relatively narrow hexagonal liquid crystalline region and a lower melting point than the ordinary alcohol ethoxylate type nonionics. 相似文献
58.
K Mori S Hama F Kato T Okamoto T Kishi H Sayo 《Chemical & pharmaceutical bulletin》1990,38(4):1100-1103
A series of arylthiolated 2,3-ethylenedioxy-1,4-benzoquinones as a coenzyme Q (CoQ) antagonist was tested for inhibition of succinate oxidase and reduced nicotinamide adenine dinucleotide (NADH) oxidase systems in the mitochondrial respiratory chain. The following characteristics were revealed: (1) 2,3-ethylenedioxy, 5-arylthio and 5,6-diarylthio groups were confirmed to be favorable for inhibition of both systems; (2) these analogs were more effective in the succinate oxidase system than in the NADH oxidase system; (3) 4' substituents on the benzene side ring had little effect on inhibitory activity; (4) the acting sites of these analogs had no strict stereospecificity. The reduced minus oxidized difference spectra revealed that these analogs inhibited the succinate oxidase system at the site between succinate and CoQ, and the NADH oxidase system at the site after cytochrome a + a3, suggesting these analogs might act as antagonists of CoQ in the succinate oxidase system. However, 5-(4'-nitrophenylthio)-2,3-ethylenedioxy-1,4-benzoquinone (If) strongly inhibited only the succinate oxidase system at the site after cytochrome a + a3. 相似文献
59.
Yoshimasa Hama Kenichi Shinohara 《Journal of polymer science. Part A, Polymer chemistry》1970,8(3):651-663
Paramagnetic species produced in polycarbonate (PC) by γ- or ultraviolet irradiation were investigated by ESR. In γ-irradiation, scissions of carbonate groups in the main chain occur. ESR spectra (g = 2.0034) composed of a sharp singlet, some broad singlets, and a small signal with hyperfine structure are obtained, and they are assigned to trapped electrons, positive radical ions, phenoxy-type free radicals, phenyl radicals, and ? O? C6H4? C(CH3)2 radicals. The G value for total yields of paramagnetic species at 77°K is 1.8. The percentage of CO and CO2, the dominant gases evolved, is 65.4 and 33.8%, respectively. In ultraviolet irradiation, energy is absorbed selectively at the surface region. The surface region becomes insoluble in methylene chloride because of crosslinking of phenyl groups. The ESR spectrum obtained at 77°K is a broad singlet and assigned to phenoxy-type free radicals, phenyl radicals, and polyenyl-type free radicals. Some differences in effects of γ- and ultraviolet irradiation of PC are discussed. 相似文献
60.
The production of gaseous OH radicals from the 300-350 nm photodissociation of H(2)O(2) that was photolytically produced on a water ice surface following the 157 nm photolysis of water ice at 90 K was directly monitored using resonance-enhanced multiphoton ionization. The translational energy distribution estimated by the time-of-flight spectrum of the OH products is represented by a Maxwell-Boltzmann energy distribution with a translational temperature of 3750+/-250 K. The rotational temperature was estimated by a spectral simulation to be 225+/-25 K. Surface defects produced by HCl deposition on the water ice contributed to the higher production rate of H(2)O(2) in the 157 nm photoirradiation of water ice while surface coverage caused by CD(3)OH deposition decreased the H(2)O(2) production rate. 相似文献