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991.
Kitazawa M Ishitsuka Y Kobayashi M Nakano T Iwasaki K Sakamoto K Arakane K Suzuki T Kligman LH 《Photochemistry and photobiology》2005,81(4):970-974
The generation of reactive oxygen species (ROS) by ultraviolet radiation (UVR) accelerates skin aging, which is known as photoaging. Because cutaneous iron catalyzes ROS generation, sequestering iron by chelating agents is thought to be an effective approach toward preventing photoaging. Previously, N-(4-pyridoxylmethylene)-l-serine (PYSer) was designed as an antioxidant to suppress iron-catalyzed ROS generation by its iron-sequestering activity. In this study, PYSer showed protective effects against skin damage in hairless mice irradiated with ultraviolet B (UV-B). Topical application of PYSer to the skin significantly delayed and/or decreased the visible wrinkle formation induced by chronic UV-B irradiation. A histological study indicated that UV-B-induced epidermal hypertrophy and lymphocytic infiltration were suppressed by PYSer. Moreover, PYSer showed suppressive activity against the UV-B-induced increase in glycosaminoglycans (GAG). These results indicate that PYSer is a promising antioxidant for the prevention of chronic skin photoaging by its iron-sequestering activity. 相似文献
992.
A technique combining a scalar wide-angle finite-difference beam-propagation method with a scalar finite-difference time-domain method is proposed in cylindrical coordinates. The propagating field in a lensed coreless fiber is simulated, and the effect of a lens on the far-field pattern is evaluated. 相似文献
993.
994.
C. Neetzel T. Ohgai T. Yanai M. Nakano H. Fukunaga 《Journal of Solid State Electrochemistry》2016,20(6):1665-1672
In this study, Co-Al2O3 nano-composite films containing parallel-oriented cobalt nano-cylinders with length-to-diameter aspect ratios of ca. 4000 are synthesized to acquire a uniaxial magnetization property. The Co nano-cylinders were electrodeposited into anodized aluminum oxide films with numerous nano-channels under a low over-potential of less than 0.1 V using an acidic aqueous solution containing CoCl2 at 75 °C. The long axis of Co nano-cylinders, which are electrodeposited at cathode potential of ?0.58 V vs. Ag/AgCl, coincides with the c axis of hexagonal close packed (hcp)-Co. The Co-Al2O3 nano-composite films show a uniaxial magnetization behavior due to the large shape anisotropy of Co nano-cylinders and the large magneto-crystalline anisotropy of the hcp-Co crystal structure. We achieved coercivity and squareness values of up to 2.4 and 1.0 kOe, respectively. This study shows an effective way to produce nano-composite films of altered coercivities. 相似文献
995.
M. Nakano H. Watanabe T. Shimizu N. Miyagawa S. Morita H. Katagiri H. Ishiguro 《Journal of Radioanalytical and Nuclear Chemistry》2000,243(2):319-322
The fire and explosion of the Bituminization Demonstration Facility at PNC Tokai Works were occurred on March 11th, 1997. As soon as the fire occurred, environmental monitoring was started. The influence of accidental release was recognized from some samples of airborne dust and surface soil on site. No influence was recognized from the samples off site except the airborne dust collected at O-arai (20 km south). The official statement by the Nuclear Safety Commission of Japan was: "It was less than the value which has an influence on the environment and health." 相似文献
996.
997.
Hata Kazufumi Tanaka Yasunori Kano N. Nakano Y. Uesugi Y. Ishijima T. 《Plasma Chemistry and Plasma Processing》2021,41(3):757-777
Plasma Chemistry and Plasma Processing - In this paper $$\hbox {CH}_4$$ / $$\hbox {H}_2$$ gas flow rate effect on polycrystalline diamond deposition was studied using a time-series exposure... 相似文献
998.
Ito M Fukuzawa K Ishikawa T Mochizuki Y Nakano T Tanaka S 《The journal of physical chemistry. B》2008,112(38):12081-12094
999.
3-thiophene- and 3-furancarboxylic acids efficiently undergo perarylation accompanied by cleavage of the three C-H bonds and decarboxylation upon treatment with excess aryl bromides in the presence of a palladium catalyst to give the corresponding tetraarylated products in good yields. 相似文献
1000.
The 18pi-sigma3- and 22pi-sigma4-phosphaporphyrins were successfully prepared by an acid-promoted condensation between a phosphatripyrrane and a 2,5-bis[hydroxy(phenyl)methyl]pyrrole, and their structures, aromaticity, and optical and electrochemical properties were disclosed. Notably, a sigma4-phosphaporphyrinogen and the 18pi-sigma3-phosphaporphyrin undergo oxidative pi-extension at the peripherally fused carbocycle to afford the 22pi-sigma4-phosphaporphyrin. 相似文献