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排序方式: 共有1722条查询结果,搜索用时 15 毫秒
81.
Koichi Mitsukura Hiromu Sakamoto Haruka Kubo Toyokazu Yoshida Toru Nagasawa 《Journal of Bioscience and Bioengineering》2010,109(6):550-553
To efficiently produce 1,3-adamantanediol (1,3-ad(OH)2) from 1-adamantanol (1-adOH), our stocks of culture strains and soil microorganisms were surveyed for hydroxylation activity towards 1-adOH. Among them, the soil actinomycete SA8 showing the highest hydroxylation activity was identified as Streptomyces sp. based on 16S ribosomal DNA sequence analysis. The reaction products were purified by silica gel column chromatography, and from NMR and MS analyses, they were identified as 1,3-ad(OH)2 and 1,4-ad(OH)2. Streptomyces sp. SA8 produced 5.9 g l? 1 1,3-ad(OH)2from 6.2 g l? 1 1-adOH in culture broth after 120 h at 25 °C. Using resting cells, 2.3 g l? 1 1,3-ad(OH)2 was produced after 96 h of incubation at a 69% conversion rate. In both cases, 1,4-ad(OH)2 was formed as a byproduct at a rate of about 15%. Strain SA8 also hydroxylated 2-adamantanol and 2-methyl-2-adamantanol. 相似文献
82.
Koh Matsumoto Kazutada Ikenaga Jun Yamamoto Kazuki Naito Yoshiki Yano Akinori Ubukata Hiroki Tokunaga Tadanobu Arimura Katsuaki Cho Toshiya Tabuchi Akira Yamaguchi Yasuhiro Harada Yuzaburo Ban Kousuke Uchiyama 《半导体学报》2011,32(1):21-23
Growth rate has a direct impact on the productivity of nitride LED production.Atmospheric pressure growth of GaN with a growth rate as high as 10μm/h and also Al0.1Ga0.9N growth of 1μm/h by using 4 inch by 11 production scale MOVPE are described.XRD of(002) and(102) direction was 200 arcsec and 250 arcsec, respectively.Impact of the growth rate on productivity is discussed. 相似文献
83.
Keiichiro Sugimoto Sayaka Sakamoto Kazuya Nakagawa Shuichi Hayashi Naoki Harada Ryoichi Yamaji Yoshihisa Nakano Hiroshi Inui 《Food chemistry》2011
Eucalyptus leaf extract (ELE) is rich in hydrolyzable tannins. We examined the effects of ELE and its constituents on lipopolysaccharide (LPS)-induced liver injury in mice. Mice fed a diet supplemented with 1% ELE were intraperitoneally administered LPS. Six hours later, the serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities were significantly lower in the ELE-supplemented mice than in the controls; LPS-induced hepatic inducible nitric oxide synthase (iNOS) expression was also suppressed. ELE lowered LPS-stimulated iNOS expression in cultured RAW 264.7 macrophages. Furthermore, the aglycones of hydrolyzable tannins, gallic acid (GA) and ellagic acid (EA), inhibited iNOS induction to a greater extent than did ELE (15-fold higher). When mice were fed a 1% GA or EA diet, the increase in the serum ALT and AST activities and hepatic iNOS expression in response to the LPS challenge were significantly attenuated. Thus, hydrolyzable tannins in ELE ameliorate LPS-induced liver injury. 相似文献
84.
R.W. Callis J.L. Doane H.J. Grunloh K. Kajiwara A. Kasugai C.P. Moeller Y. Oda R.A. Olstad K. Sakamoto K. Takahashi 《Fusion Engineering and Design》2009,84(2-6):526-529
Initial testing on the Japan Atomic Energy Agency Gyrotron Test Stand of ITER-relevant TL components, has shown reasonable efficiencies, but identified that trapped modes between closely located miter bends, as well as mode conversion at miter bends can lead to excessive heating of the connecting waveguides. General Atomics has designed, built, and will test components to address this issue as well as ITER relevant components that have not been tested at the levels of 1 MW, 170 GHz, for extended pulse lengths. Some of the components that will be tested are ultra low loss miter bends, dc breaks, polarizers, power monitors, bellows, waveguide switches, waveguide cooling clamps, etc. Details of the components and test results will be presented. 相似文献
85.
Yoshihiro Sakamoto Kazuro Murayama Yasushiro Nishioka Hideyo Okushi 《Diamond and Related Materials》2009,18(5-8):759-763
Time-resolved band edge luminescence spectrum in IIa diamond has been measured with the 5th harmonics of a pulsed YAG laser (5.82 eV) and an ICCD image intensifier of 5 ns gate width at 290 K. The time-resolved luminescence spectrum is decomposed into three components of free exciton (FE), excitonic complex (EC) and electron-hole plasma (EHP). The decay times of the FE and EC luminescence are 45 and 27 ns, respectively and that of the EHP luminescence has been seen to be shorter than the gate width, 5 ns. The low energy onset of the EHP luminescence spectrum has been observed to decrease with increasing excitation density and attains the onset of the electron-hole drop luminescence spectrum at the excitation density of 0.6 J/cm2, at which the electron-hole pair density is 1.2 × 1020 cm? 3. Furthermore, the excitation density dependences of the FE, EC and EHP luminescence intensities are explained with the percolation theory. 相似文献
86.
Shiplu Roy Chowdhury Yuichi Muneyuki Yasunori Takezawa Masahiro Kino-oka Atsuhiro Saito Yoshiki Sawa Masahito Taya 《Journal of Bioscience and Bioengineering》2010,109(3):310-313
The transitional behaviors of myoblasts toward differentiation were investigated in the cultures at the low and high seeding densities (respectively, X0 = 1.0 × 103 and 2.0 × 105 cells/cm2). In the culture at the low seeding density, an increase in confluence degree accompanied a decrease in growth potential (Rp), being Rp = 0.85 and 0.11 at t = 48 and 672 h, respectively. Myoblasts seeded at the high density resulted in the immediate cessation of growth with keeping the low range of Rp = 0.02–0.09 throughout the culture. The reduction of Rp led to the generation of three subpopulations of cells in proliferative, quiescent and differentiated states. Close cell contacts in the confluent state of high seeding culture induced cell quiescence to a higher extent with suppressing differentiation. 相似文献
87.
88.
Involvement of cytochrome P450 in hydroxylation of propylbenzene by Fusarium moniliforme strain MS31
Atsuko Uzura Takahiro Suzuki Tohoru Katsuragi Yoshiki Tani 《Journal of Bioscience and Bioengineering》2001,92(6):580
Fusarium moniliforme strain MS31 can oxidize propylbenzene to (R)-1-phenylpropanol with what may be a cytochrome P450. Hydroxylation of propylbenzene needed molecular oxygen, and NADPH as a coenzyme gave a higher yield than NADH. The hydroxylation proceeded further when FAD and FMN were added than in their absence, suggesting that the enzyme was a flavo-protein. Carbon monoxide inhibited the hydroxylation, as did other cytochrome P450 inhibitors such as SKF 525A and miconazole. These characteristics matched those of a microsomal cytochrome P450 monooxygenase system that contained NADPH-cytochrome P450 reductase. 相似文献
89.
Recent findings on amino acid transporter genes are reviewed with particular focus on matching previously described transport systems to individual genes. Functional studies using cloned and expressed transporters are considered as the critical tool allowing identification of the functional properties of individual genes. Specifically, these experiments allow identification of the transported substrate amino acids and of the transport mechanism. We focus on the very recent discovery and properties of the heterodimeric family of amino acid transport proteins where two subunits encoded in different genes are required. For these transporters, co-expression of both subunits is mandatory for functional studies. The field of placental amino acid transport is further complicated by complexities arising from both gestational age-specific and species-specific gene expression. The function of the transporter also depends on its cellular localization in the trophoblast. In addition, for transporters that are coupled to ion gradients, both membrane potential and ion pumping will contribute to the rate of amino acid delivery to the fetus. Regulation of function is important not only for fetal nutrition but also for specific additional aspects of placental biology. 相似文献
90.
Kameda Atsushi Yamamoto Masahito Uejima Hiroki Hagiya Masami Sakamoto Kensaku Ohuchi Azuma 《Natural computing》2005,4(2):103-126
In this paper, we propose a new architecture for a multi-state DNA machine whose conformation of repeated hairpin structures changes sequentially in response to input oligomers. As an application of the machine, we also propose molecular memory in which the machine is used as a memory unit. Addressing in the memory is realized through state transitions of the machine. We then describe a method for designing DNA sequences of the machine, which exhaustively checks conformational changes of the machine by dividing its secondary structure into hairpin units. The method is based on the minimum free energy of the structure, the structure transition paths, and the total frequency of optimal and suboptimal structures. DNA sequences designed by the method were tested in a chemical experiment in which a machine consisting of two hairpins was actually constructed. As a result, we verified that the multi-state DNA machine realized the expected changes in its secondary structure. 相似文献