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排序方式: 共有825条查询结果,搜索用时 15 毫秒
21.
Ke Fang Yuki Murakami Seiji Kanda Takaki Shimono Anh Tuan Dang Mitsuaki Ono Toshimasa Nishiyama 《International journal of molecular sciences》2022,23(14)
Osteoporosis is a common bone disease, particularly in menopausal women. Herein, we screened four Kampo medicines (Unkeito (UKT), Kamishoyosan (KSS), Kamikihito (KKT), and Ninjinyoeito (NYT)), frequently used to treat menopausal syndromes, for their effects on receptor activator of nuclear factor-kappaB ligand (RANKL)-induced osteoclast differentiation in RAW 264 cells. Considering that UKT exhibited the most potent effect, we examined its effect on RANKL-induced osteoclastogenesis, the induction of osteoclast apoptosis, and the mechanisms underlying its effects. UKT inhibits RANKL-induced osteoclast differentiation in the early stage and decreases osteoclast-related genes, including tartrate-resistant acid phosphatase (Trap), dendritic cell-specific transmembrane protein (Dcstamp), matrix metalloproteinase-9 (Mmp9), and cathepsin K (Ctsk). Specifically, UKT inhibits the nuclear factor of activated T cells 1 (NFATc1), which is essential for osteoclastogenesis. UKT increases Bcl6, which antagonizes NFATc1 and Dc-stamp, thereby blocking the progression of osteoclasts to maturation. UKT also decreased nuclear translocation by downregulating the activity of p65/NF-κB. In addition, UKT enhances mononuclear osteoclast apoptosis via activation of caspase-3. Herein, we demonstrate that UKT suppresses RANKL-mediated osteoclastogenesis via the Blimp1–Bcl6 and NF-κB signaling pathways and enhances mononuclear osteoclast apoptosis. Furthermore, UKT prevents bone loss in OVX mice. Thus, UKT might be a potential therapeutic agent for postmenopausal osteoporosis. 相似文献
22.
Noritsugu Hashimoto Seiji Niijima Jun-ichi Inagaki 《Journal of the European Ceramic Society》2009,29(14):3039-3043
Solid oxide fuel cells (SOFCs) are very attractive for their high energy conversion efficiency and low emissions. Generally, a supported layer of SOFCs is fabricated by tape casting, using an organic solvent. Recently, a slurry based on water instead of an organic solvent has been sought in order to avoid environmental pollution. In this study, the anode of SOFCs was fabricated by aqueous tape casting, and the electrolyte and the cathode were deposited by screen printing. The I–V characteristics of the cell thus obtained were evaluated. As a result, an 80 mm diameter-sized cell with a power density of 0.33 W/cm2 at 800 °C was successfully fabricated by controlling sintering conditions. 相似文献
23.
In this paper, photoresponsive behavior of multi-bilayered films having precisely controlled layer thickness prepared by stacking an azo-functionalized polymer liquid crystal, PMAzXAc, and polyvinyl alcohol alternatively, PVA, is described. The multi-bilayered films were found to reflect a light of specific wavelength depending on the layer thickness and refractive index, and showed the reversible change in the reflection intensity by irradiation with visible and UV lights. The change in the reflection intensity was brought about by change in the molecular orientation of PMAzXAc between an out-of-plane orientation and a photo-induced isotropic state, and was strongly dependent on the number of methylene spacer of PMAzXAc linking the azobenzene side group with the acrylate polymer main chain. PMAz6Ac with hexa-methylene spacer showed the largest change in the reflection intensity, while smaller change in the reflection intensity was observed for PMAzXAc having shorter or longer methylene spacer than 6. The effect of the methylene spacers on the photochemical change in the molecular orientation of azobenzene chromophores in the multi-bilayered films will be discussed. 相似文献
24.
The swelling and adsorption behavior of poly(N-isopropylacrylamide)–SiO2 hybrid gels, derived from copolymerization of N-isopropylacrylamide and 3-methacryloxypropyltrimethoxysilane (MPTMOS) and following hydrolysis and condensation, were investigated. The hybrid gels exhibited temperature dependence of both the swelling ratio and adsorption of solutes, and their temperature dependence of both the swelling ratio and adsorption of solutes, and their temperature dependence was related to the MPTMOS content in the hybrid gels. In addition, the modification of thermosensitive properties of the hybrid gels could be achieved by treatment with other silane compounds. © 1996 John Wiley & Sons, Inc. 相似文献
25.
Kadota M Imanaka M Hino S Nanba J Take S Nakazawa H 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2003,44(1):69-72
An analytical method was developed for determination of residual avoparcin in chicken muscle by measuring alpha- and beta-avoparcin, major components of the pharmaceutical preparation avoparcin, using HPLC with UV and amperometric detectors. The analytical HPLC was run on a Cosmosil 5C18-AR column (4.6 mm x 25 cm) with a gradient formed from A: 2.5% acetic acid, 0.01 mol/L sodium heptane sulfonic acid-acetonitrile (88.5:11.5) (pH 4.0) and B: 2.5% acetic acid-acetonitrile (10:90), using UV and amperometric detection (AMD) with glassy-carbon electrode (+900 mV). Avoparcin was extracted from chicken muscle by homogenization with methanol-0.2 mol/L sulfuric acid (6:4) followed by centrifugation after pH adjustment to 4 with 1 mol/L sodium hydroxide. The supernatant was evaporated to dryness, and the residue was dissolved in water. The aqueous layer was adjusted to pH 4 by adding 1 mol/L sodium hydroxide. Then it was purified on a Sep-Pak tC18 plus ENV cartridge. The cartridge was washed with water, and retained substances were eluted with 50% methanol. The eluate was evaporated to dryness under reduced pressure. The residue was dissolved in water and determined by HPLC. Recoveries of avoparcin spiked in chicken muscle were 73.1-88.1% at levels of 2-10 micrograms/g. The detection limits were 0.5 microgram/g (UV) and 0.2 microgram/g (AMD). 相似文献
26.
27.
Daichi Yazaki Tokuhisa Kawawaki Daisuke Hirayama Masanobu Kawachi Kosaku Kato Sota Oguchi Yuichi Yamaguchi Soichi Kikkawa Yoshiya Ueki Sakiat Hossain D. J. Osborn Fumihiko Ozaki Shunsuke Tanaka Jun Yoshinobu Gregory F. Metha Seiji Yamazoe Akihiko Kudo Akira Yamakata Yuichi Negishi 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(34):2208287
For the realization of a next-generation energy society, further improvement in the activity of water-splitting photocatalysts is essential. Platinum (Pt) is predicted to be the most effective cocatalyst for hydrogen evolution from water. However, when the number of active sites is increased by decreasing the particle size, the Pt cocatalyst is easily oxidized and thereby loses its activity. In this study, a method to load ultrafine, monodisperse, metallic Pt nanoclusters (NCs) on graphitic carbon nitride is developed, which is a promising visible-light-driven photocatalyst. In this photocatalyst, a part of the surface of the Pt NCs is protected by sulfur atoms, preventing oxidation. Consequently, the hydrogen-evolution activity per loading weight of Pt cocatalyst is significantly improved, 53 times, compared with that of a Pt-cocatalyst loaded photocatalyst by the conventional method. The developed method is also effective to enhance the overall water-splitting activity of other advanced photocatalysts such as SrTiO3 and BaLa4Ti4O15. 相似文献
28.
Hirahara Y Kimura M Inoue T Uchikawa S Otani S Hirose H Suzuki S Uchida Y 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2006,47(5):225-231
The applicability of GC, GC/MS and liquid chromatography with tandem mass spectrometry (LC/MS/MS) to screening for 140 pesticides in agricultural products was examined. Validation of multi-residue screening methods for the determination of 88 pesticides in 12 crops (asparagus, cauliflower, burdock, carrot, broccoli, spinach, matsutake mushroom, orange, soybean, sesame, millet and tea) was done by GC and GC/MS. Of the 88 pesticides, 63 were obtained with recoveries in the range from 50 to 150% at the 0.1 microg/g level in the 12 crops. Applicability of the official methods in Japan to 74 pesticides, including 22 pesticides with low recovery (< 50%) by GC or GC/MS analysis, was also examined by LC/MS/MS. LC/MS/MS acquisition parameters were established for 67 pesticides in positive and negative electrospray ionization (ESI) modes. Of 67 pesticides validated in 7 crops using LC/MS/MS at the 0.1 microg/g level, 44 showed recoveries in the range from 50 to 150%. The occurrence of matrix interference in LC/MS/MS can lead to false-positive detection of MCPA in spinach, cabbage and orange and false-negative detection of four pesticides in orange, spinach, apple and unpolished rice. Good linearity was observed in the studied ranges by GC, GC/MS (r > 0.990) and LC/MS/MS (r > 0.995). Of the total of 140 pesticides validated by GC, GC/MS and LC/MS/MS, 107 were newly recognized as suitable subjects for screening. 相似文献
29.
Akio Kishi Seiji Kuroda Tadanobu Inoue Takeshi Fukushima Hisami Yumoto 《Journal of Thermal Spray Technology》2008,17(2):228-233
A new testing procedure to evaluate the interfacial toughness of thermal-sprayed coatings has been developed. The newly designed
test specimen is a modification of the pin test with an artificially introduced weak interface, which is expected to open
up easily under tensile loading and act as a circumferential precrack along the interface between a coating and the substrate.
This configuration makes it possible to calculate the stress intensity factor K
Int at the tip of the precrack, which can be expressed as
, where σ0 is the apparent average stress, a the crack length, R the specimen radius, and F
I the geometrical correction function. Finite-element analysis was carried out to calculate the correction function F
I for various values of a/R. In the experiments, the flat surface of a pin was grit-blasted and a ring-shaped area from the periphery was covered with
carbon using a pencil and set into a mating dice. SUS316L stainless steel was plasma-sprayed onto the flat surface of the
pin and the dice. Then, tensile load was applied to the pin to break the weak interface containing the carbon and finally
the unmodified coating-substrate interface. The load required to pull out the pin was measured for various specimen parameters
such as a and R. The results indicate that the adhesion of the tested coatings can be represented by interface toughness of 1.9 ± 0.1 MPa m1/2. As a consequence, this testing procedure can be considered as a viable method to evaluate adhesion of a thermal-sprayed
coating on a substrate. 相似文献
30.
Zhensu Zeng Seiji Kuroda Jin Kawakita Masayuki Komatsu Hidenori Era 《Journal of Thermal Spray Technology》2010,19(1-2):128-136
The oxidation behavior of iron binary powders with addition of Si (1, 4 wt.%) and B (1, 3 wt.%) and that of a Ni-Cr based alloy powder with Si (4.3 wt.%), B (3.0 wt.%), and C (0.8 wt.%) additions during atmosphere plasma spray (APS) have been investigated. Analysis of the chemical composition and phases of oxides in the captured in-flight particles and deposited coatings was carried out. The results show that the addition of Si and B to iron effectively reduced the oxygen contents in the coatings, especially during the in-flight period at higher particles temperature. Ni-Cr based alloy powder with Si, B, and C additions reduced the oxidation of the base alloys significantly. Preferential oxidation and subsequent vaporization of Si, B, and C from the surface of the sprayed particles are believed to play a major role in controlling oxidation in the APS process. 相似文献