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排序方式: 共有137条查询结果,搜索用时 78 毫秒
81.
Haruo Takeshita Junko Fujihara Reiko Iida Hideaki Kato Toshihiro Yasuda 《Electrophoresis》2013,34(24):3361-3369
Many nonsynonymous SNPs in the human DNase II gene (DNASE2), potentially relevant to autoimmunity in conditions such as rheumatoid arthritis, have been identified, but only limited population data are available and no studies have evaluated whether such SNPs are functional. Genotyping of all the 15 nonsynonymous human DNase II SNPs was performed in three ethnic groups including 16 different populations using the PCR‐restriction fragment length polymorphism technique. A series of constructs corresponding to each SNP was examined. Fifteen nonsynonymous SNPs in the gene, except for p.Val206Ile in a Korean population, exhibited a mono‐allelic distribution in all of the populations. On the basis of alterations in the activity levels resulting from the corresponding amino acid substitutions, four activity‐abolishing and five activity‐reducing SNPs were confirmed to be functional. The amino acid residues in activity‐abolishing SNPs were conserved in animal DNase II. All the nonsynonymous SNPs that affected the catalytic activity of human DNase II showed extremely low genetic heterogeneity. However, a minor allele of seven SNPs producing a loss‐of‐function or extremely low activity‐harboring variant could serve as a genetic risk factor for autoimmune dysfunction. These functional SNPs in DNASE2 may have clinical implications in relation to the prevalence of autoimmune diseases. 相似文献
82.
Kohei Saito Yuya Watabe Takashi Fujihara Toshiyuki Takayanagi Jun-ya Hasegawa 《Journal of computational chemistry》2020,41(11):1130-1138
Spin-inversion mechanisms in O2 binding to a model heme complex, consisting of Fe(II)-porphyrin and imidazole, were investigated using density-functional theory calculations. First, we applied the recently proposed mixed-spin Hamiltonian method to locate spin-inversion structures between different total spin multiplicities. Nine spin-inversion structures were successfully optimized for the singlet–triplet, singlet–quintet, triplet–quintet, and quintet–septet spin-inversion processes. We found that the singlet–triplet spin-inversion points are located around the potential energy surface region at short Fe–O distances, whereas the singlet–quintet and quintet–septet spin-inversion points are located at longer Fe–O distances. This suggests that both narrow and broad crossing models play roles in O2 binding to the Fe-porphyrin complex. To further understand spin-inversion mechanisms, we performed on-the-fly Born-Oppenheimer molecular dynamics calculations. The reaction coordinates, which are correlated to the spin-inversion dynamics between different spin multiplicities, are also discussed. 相似文献
83.
Effect of Solvent on the Radical Copolymerizability of Styrene with 3(2-Methyl)-6-methylpyridazinone
Jun-Ichi Asakura Shogi Kawabata Hisashi Fujihara Yoshio Matsubara Masakuni Yoshihara Toshihisa Maeshima 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(7-8):1045-1054
Abstract The radical copolymerization of styrene (St, M1) with 3(2-methyl)-6-methylpyridazinone (I, M2) has been carried out in several p-substltuted phenols at 60 and 70°C. Monomer reactivity ratios (r1) and activation parameters of copolymerization were found to be affected by phenols. The values of the activation energy (δδE?) and entropy (δδS?) increased with the increase of the interaction of I with the solvents. Linear relationships were observed between the [sgrave]-values of p-substituents of phenols and the values of log 1/r1 and also of δδE? and δδS?. The radical copolymerization of St (M1) with 6-substituted 3(2-methyl)-pyridazinone was also carried out. 相似文献
84.
85.
86.
Naomichi Furukawa Keiko Kishimoto Satoshi Ogawa Tsutomu Kawai Hisashi Fujihara Shigeru Oae 《Tetrahedron letters》1981,22(44):4409-4412
Methyl 2-pyridyl sulfoxide was found to be an excellent phase transfer catalyst which promotes simple SN2 type displacement reactions of alkyl halides with some nucleophiles. 相似文献
87.
88.
Ethers undergo addition to imines in the presence of dimethylzinc and air through a radical process. [reaction: see text] 相似文献
89.
Soeta T Nagai K Fujihara H Kuriyama M Tomioka K 《The Journal of organic chemistry》2003,68(25):9723-9727
The synthetic procedure of a chiral amidophosphine ligand 5 bearing two bulky substituents, 2,4,6-trimethylphenylmethyl or 2,4,6-triisopropylphenylmethyl groups, on the pyrrolidine ring was improved by employing the borane-THF reduction of the lactam-alcohol intermediate 8. The resulting amino alcohol was selectively acylated to give an amide-alcohol 11, which was then converted to the chloride 12 in 55-73% yields by the treatment with methanesulfonyl chloride in collidine. The reaction of the chloride 12 with NaPPh(2) in dioxane-THF gave an amidophosphine 5 in an acceptably high 82-83% yields. Addition of a hexane solution of dialkylzinc reagent to a mixture of catalytic amount of an amidophosphine 5, copper species, and N-toluenesulfonylimine 1a of benzaldehyde in toluene provided a solution which gave the alkylated amide 3 in high yield and enantioselectivity up to 96%. A survey of copper sources and solvents concluded that copper(II) ditriflate and copper(I) triflate-benzene complex as good copper sources and toluene as a choice of solvent. N-Toluenesulfonylimines 1a-e of arylaldehydes, furfural, and alkanals were successfully ethylated with diethylzinc to give the corresponding N-toluenesulfonylamides 3aE-eE in satisfactorily good 69-97% yields and high 86-96% enantioselectivities. 相似文献
90.
Hosono E Fujihara S Kimura T 《Langmuir : the ACS journal of surfaces and colloids》2004,20(9):3769-3774
This paper first reports fabrication of macro/nanotextured rare-earth oxyfluoride films. Usage of ion-modified lanthanum diacetate hydroxide (LDAH) as self-templates was successful in producing nanoparticulate lanthanum oxyfluoride (LaOF) films. LDAH template films were deposited on glass substrates through a chemical bath deposition in solutions composed of lanthanum acetate sesquihydrate, methanol, trifluoroacetic acid, and aqueous ammonia. The LDAH films had a unique, nestlike morphology owing to a two-dimensional hexagonal crystal growth. Modification of LDAH with trifluoroacetate ions led to formation of LaOF after pyrolyzing the template films at temperatures of 400-600 degrees C in air. The resultant LaOF films had a nanoparticulate porous microstructure, maintaining the morphology of the original LDAH template films. It was also successful to incorporate Eu3+ ions into LaOF through deposition of the LDAH film in a solution containing europium acetate tetrahydrate. The characteristic photoluminescence from Eu(3+) was observed with an ultraviolet-light excitation at 273 nm, indicating that Eu3+ was homogeneously distributed in LaOF host crystals. Thus the ion-modification of LDAH was also demonstrated to be a useful method for preparing nanostructured rare-earth oxyfluoride materials havingvarious cationic compositions. 相似文献