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排序方式: 共有1647条查询结果,搜索用时 15 毫秒
111.
Formate dehydrogenase gene of Arabidopsis thaliana is induced by formaldehyde and not by formic acid 总被引:1,自引:0,他引:1
Fukusaki E Ikeda T Shiraishi T Nishikawa T Kobayashi A 《Journal of Bioscience and Bioengineering》2000,90(6):691-693
Variability of expression of formate dehydrogenase (FDH) caused by uptake of C-1 compounds was examined by using Arabidopsis thaliana as a model plant. Effects of uptake of several C-1 compounds were evaluated by Northern blot analysis using cDNA of A. thaliana FDH prepared by cloning on the basis of known sequence. As a result, expression of the FDH gene in A. thaliana was not intensely influenced by formic acid, an inherent substrate for FDH, but strongly induced by its reduced form, formaldehyde. 相似文献
112.
Yoshida N Akazawa S Karino T Ishida H Hata Y Katsuragi T Tani Y Takagi H 《Journal of Bioscience and Bioengineering》2007,104(5):424-427
We found 11 genes (FAO1-11) encoding putative oxidoreductases in the Aspergillus oryzae genome, which are similar to fungal fructosyl-amino acid oxidases. The cDNAs corresponding to the genes were cloned and expressed in Escherichia coli. rFao2 had fructosyl-amino acid oxidase activity, whereas rFao1 did not show any enzyme activity, even though the deduced amino acid sequence of Fao1 is identical to that of one of the fructosyl-amino acid oxidase isozymes from Aspergillus oryzae. rFao7 and rFao8 showed oxidase activity toward sarcosine, L-pipecolate, and L-proline. rFao10 was active toward only sarcosine, of the substrates tested. The functions of the other proteins were also predicted from a phylogenetic analysis. 相似文献
113.
Ishiwata H Abe Y Kubota H Kawasaki Y Takeda Y Maitani T Nishijima M Fukasawa Y 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2002,43(1):49-56
The mean concentrations and daily intake of four antifungal agents were estimated based on the results of an analysis of 7,005 samples of food obtained in official inspections by Japanese local governments in fiscal year 1998. The mean concentration of diphenyl was 0.0004% of the allowable limit, and those of imazalil, o-phenylphenol, and thiabendazole were 14.0%, 3.5%, and 5.7%, respectively. The daily intakes of these antifungal agents per person, estimated from their concentrations and the daily consumption of the foods, were 0.000326, 1.89, 11.5, and 23.3 micrograms, respectively, and assuming a body weight of 50 kg, the amounts of these antifungal agents consumed were 0.000013%, 0.15%, 0.12%, and 0.47% of the acceptable daily intake, respectively. These values are similar to the values obtained on the basis of the results of the official inspection in fiscal years 1994 and 1996, except that the amount of diphenyl is much lower (1/100). 相似文献
114.
Yu Matsuda Toru Uchida Suguru Suzuki Ryota Misaki Hiroki Yamaguchi Tomohide Niimi 《Microfluidics and nanofluidics》2011,10(1):165-171
For the development of micro- and nano-technology, it has been strongly desired to understand thermo-fluid phenomena inside
or around micro- and nano-devices. An optical measurement technique based on the absorption and the emission of photons by
molecules is useful for experimental analyses of thermo-fluid phenomena of micro and nanoflows. The pressure-sensitive paint
(PSP) technique is a potential diagnostic tool for pressure measurements of micro/nano gas flows because it works as a so-called
“molecular sensor”. However, the micro-scale measurement of PSP has been limited by the aggregation of the luminescent molecules
and their thick film due to the use of a polymer binder. In our previous work, we adopted the Langmuir–Blodgett (LB) technique
to fabricate pressure-sensitive molecular film (PSMF) with ordered molecular assemblies, and investigated properties of PSMF.
In this study, a novel approach to enhance the luminescent intensity of PSMF is proposed, and the pressure distribution in
a micro-nozzle is successfully measured by using PSMF. Moreover, we compared the pressure distribution measured by PSMF with
that numerically analyzed by the direct simulation monte carlo (DSMC) method, showing good agreement with each other. 相似文献
115.
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117.
Electron beam irradiation of Ni particles (diameter: ∼500 nm) in a transmission electron microscope (TEM) formed small secondary particles, which moved randomly on an amorphous carbon film. Catalytic graphitization occurred along the path traced by the moving particles. It is generally well known that heat treatment is needed to produce catalytic graphitization of an amorphous carbon. However, we rapidly produced catalytic graphitization in the presence of sputtered Ni particles by focused electron beam irradiation in the TEM although no external heating was employed. 相似文献
118.
The incorporation of Eu ions into GaN has been studied using combined excitation-emission spectroscopy for samples that were in situ doped during organometallic vapor-phase epitaxy (OMVPE) growth. The obtained fingerprints of characteristic emission spectra are subsequently used to determine the coupling of the Eu ions to the crystal lattice. We find a majority site, which exhibits coupling to bulk-like phonon modes as well as a localized phonon mode. For this site, we also find that the zero-phonon line of the 7F0 to 5D0 transition, which is forbidden, is much weaker than the phonon-coupled excitation transitions. The ratio of zero-phonon to phonon-coupled transition strength depends on the crystalline quality of the layer. These observations are consistent with the assignment of the majority site to an unperturbed Eu ion on Ga position. We find that the relative abundance of the majority site is strongly underestimated whenever the zero-phonon 7F0 to 5D0 excitation transition is used as a measure. 相似文献
119.
Syusaku Koie Gentaro Tanaka Hiroki Fukumoto Take-aki Koizumi Takakazu Yamamoto 《Reactive and Functional Polymers》2013,73(9):1180-1187
π-Conjugated polymers based on 1-aminopyrrole and 4-amino-1,2,4-triazole were prepared. Pd-catalyzed organometallic polycondensation gave poly(arylene-ethynylene) (PAE)-type π-conjugated polymers consisting of BOC-protected 4-amino-1,2,4-triazole (Taz(BOC)) units (BOC = t-butoxycarbonyl). The number average molecular weights (Mn) were determined to be 5200–19,200 using GPC. An alternating copolymer of Taz(BOC) and bithiophene (Th–Th) units, P(Taz(BOC)-Th-Th)n-Pd, with an Mn of 10,800 was also prepared by Pd-catalyzed organometallic polycondensation. (Taz(BOC)-Th-Th)n-Pd showed a UV–Vis absorption peak at λmax = 425 nm, which is reasonable for a π-conjugated five-membered ring polymer with a coplanar structure. The deprotection of the BOC group of the polymers proceeded at 200 °C; this BOC-deprotection was investigated using a model compound. The optical and electrochemical properties of the π-conjugated polymers are reported. 相似文献
120.