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91.
Makoto Kunisada Taro Masaki Ryusuke Ono Hironobu Morinaga Eiji Nakano Flandiana Yogianti Kunihiro Okunishi Hiroshi Sugiyama Chikako Nishigori 《Photochemistry and photobiology》2013,89(3):649-654
The UVA is currently thought to be carcinogenic because, similar to UVB, it induces the formation of cyclobutane pyrimidine dimers (CPDs). Various drugs have been reported to cause photosensitive drug eruptions as an adverse effect. Although the precise mechanism of photosensitive drug eruption remains to be elucidated, it is generally accepted that free radicals and other reactive molecules generated via UV‐irradiated drugs play important roles in the pathogenesis of photosensitive drug eruptions. The waveband of concern for photo‐reactive drugs is UVA‐visible light, but some extend into the UVB region. We tested whether photosensitive drugs could enhance CPD formation after UVA exposure by using isolated DNA in the presence of several reported photosensitive drugs using high‐performance liquid chromatography. We found that the diuretic agent hydrochlorothiazide (HCT) significantly enhanced the production of TT dimers over a wide range of UVA. Furthermore, we investigated whether UVA plus HCT could enhance CPD production in xeroderma pigmentosum model mice defective in nucleotide excision repair. Immunofluorescence studies showed that CPD formation in the skin significantly increased after 365 nm narrow‐band UVA irradiation in the presence of HCT, compared with that in wild‐type mice. HCT could be used with caution because of its enhancement of UVA‐induced DNA damage. 相似文献
92.
Hiroshi Mukai Shoji Miyazaki Shigeo Umetani Sorin Kihara Masakazu Matsui 《Analytica chimica acta》1989
Solvent extraction of europium (III), zinc (II) cobalt (II) with α-acyl-d-camphor and optically active isomers of quinine and quinidine was studied in order to obtain information on chirality recognition based on adduct formation between a chiral metal chelate and optically active isomers. It was possible to differentiate clearly between the adduct formation of quinine and that of quinidine in the synergic extraction of cobalt and europium with 3-heptafluorobutyryl- d-camphor and cobalt with 3-trifluoroacetyl-d-camphor. 相似文献
93.
Synthesis of well-defined polystyrene with multi-functional end groups utilizing cyclotriphosphazene
Kenzo Inoue Sadao Negayama Tomoyuki Itaya Minoru Sugiyama 《Macromolecular rapid communications》1997,18(3):225-231
Telechelic polystyrenes with five benzyl chloride moieties at the polymer end (PSt-E) were prepared by coupling reaction of polystyryllithium with hexakis(4-chloromethyl-phenoxy)cyclotriphosphazene ( 4 ). The coupling reaction occurs almost quantitatively and unfavorable side reactions were not operative. When a mole ratio [ 4 ]/[sec-BuLi] = 9.3 was used, polystyrenes with cyclophosphazene carrying five benzyl chloride moieties at the polymer end (PSt-E) were obtained in more than 90% yield, which have narrow and predictable molecular weights (M w/M n = 1.05). A star shaped polystyrene with phosphazene core could also be prepared by using excess polystyryl anions. 相似文献
94.
Lithium‐Ion Endohedral Fullerene (Li+@C60) Dopants in Stable Perovskite Solar Cells Induce Instant Doping and Anti‐Oxidation 下载免费PDF全文
Dr. Il Jeon Dr. Hiroshi Ueno Seungju Seo Dr. Kerttu Aitola Ryosuke Nishikubo Prof. Akinori Saeki Dr. Hiroshi Okada Prof. Gerrit Boschloo Prof. Shigeo Maruyama Prof. Yutaka Matsuo 《Angewandte Chemie (International ed. in English)》2018,57(17):4607-4611
Herein, we report use of [Li+@C60]TFSI? as a dopant for spiro‐MeOTAD in lead halide perovskite solar cells. This approach gave an air stability nearly 10‐fold that of conventional devices using Li+TFSI?. Such high stability is attributed to the hydrophobic nature of [Li+@C60]TFSI? repelling moisture and absorbing intruding oxygen, thereby protecting the perovskite device from degradation. Furthermore, [Li+@C60]TFSI? could oxidize spiro‐MeOTAD without the need for oxygen. The encapsulated devices exhibited outstanding air stability for more than 1000 h while illuminated under ambient conditions. 相似文献
95.
An analytical method was established for the simultaneous determination of 39 polycyclic aromatic hydrocarbons (PAHs) in air. The method was applied to a survey of gaseous and particulate PAHs in household indoor air. The survey was performed in 21 houses in the summer of 1999 and in 20 houses in the winter of 1999-2000 in Fuji, Japan. Thirty-eight PAHs were determined in indoor and outdoor air in the summer, and 39 PAHs were determined in indoor and outdoor air in the winter. The concentrations of gaseous PAHs in indoor air tended to be higher than those in outdoor air in the summer and winter. The concentrations of particulate PAHs in indoor air were the same as or lower than those in outdoor air in the summer and winter. PAH profiles, correlations between PAH concentrations, and multiple regression analysis were used to determine the factors affecting the indoor PAH concentrations. These results showed that gaseous PAHs in indoor air were primarily from indoor emission sources, especially during the summer, and that indoor particulate PAH concentrations were significantly influenced by outdoor air pollution. 相似文献
96.
The synthesis of taurospongin A has been achieved using, as a key step, a pi-allyltricarbonyliron lactone complex to control a highly stereoselective addition of a methyl group to a carbonyl unit located in the side chain of the complex. 相似文献
97.
Ito S Sugiyama H Yoshifuji M 《Angewandte Chemie (International ed. in English)》2000,39(15):2781-2783
98.
K. Sugiyama 《Colloid and polymer science》1978,256(2):204
Ohne Zusammenfassung 相似文献
99.
100.
Shinji Fushiya Yoshikazu Sato Shigeo Nozoe Kyosuke Nomoto Tsunematsu Takemoto Sei-ichi Takagi 《Tetrahedron letters》1980,21(32):3071-3072
A new amino acid derivative possessing an iron chelating activity was isolated from root washings of water cultured under iron deficient conditions. The structure of this compound, avenic acid A has been determined as 2(S),3′(S),3″(S)-N-[3-(3-hydroxy-3-carboxypropylamino)-3-carboxypropyl]-homoserine (1) on the basis of chemical and spectroscopic evidence. 相似文献