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排序方式: 共有506条查询结果,搜索用时 15 毫秒
181.
Kaori Kimura‐Kataoka Toshihiro Yasuda Junko Fujihara Tomoko Toga Rei‐Ichiro Ono Yosuke Otsuka Misuzu Ueki Reiko Iida Rie Sano Tamiko Nakajima Yoshihiko Kominato Hideaki Kato Haruo Takeshita 《Electrophoresis》2012,33(18):2852-2858
Five SNPs in the human DNase II gene have been reported to be associated with rheumatoid arthritis (RA). Genotype and haplotype analysis of 14 SNPs, nine SNPs of which reported in the NCBI dbSNP database in addition to these five SNPs, was performed in healthy subjects. The enzymatic activities of the amino acid substituted DNase II corresponding to each SNP and serum DNase II in healthy Japanese, and promoter activities derived from each haplotype of the RA‐related SNPs were measured. Significant correlations between genotype in each RA‐related SNP and enzymatic activity levels were found; alleles associated with RA exhibited a reduction in serum DNase II activity. Furthermore, the promoter activities of each reporter construct corresponding to predominant haplotypes in three SNPs in the promoter region of the gene exhibited significant correlation with levels of serum DNase II activity. These findings indicate these three SNPs could alter the promoter activity of DNASE2, leading to a decline in DNase II activity in the serum through gene expression. Since the three SNPs in the promoter region of the DNase II gene could affect in vivo DNase II activity through reduction of the promoter activity, it is feasible to identify these SNPs susceptible to RA. 相似文献
182.
Uchiyama Y Okubo F Akai K Fujii Y Henares TG Kawamura K Yao T Endo T Hisamoto H 《Lab on a chip》2012,12(1):204-208
We describe a new method for fabricating a capillary-type sensor, called a combinable poly(dimethyl siloxane) (PDMS) capillary (CPC) sensor. The method for preparing the CPC simplifies enzyme inhibitor assays into a simple, single step assay. The sample inhibitor solution is introduced by capillary action. This triggers the spontaneous dissolution of physically adsorbed fluorescent substrates, and the substrate mixes with the inhibitor. This is followed by competitive reaction with insoluble enzyme to give a fluorescence response. CPC is composed of a convex-shaped PDMS stick containing reagents immobilized in an insoluble coating, and a concave-shaped PDMS stick containing reagents immobilized in a soluble coating. Since the concave-shaped PDMS has a deeper channel than the convex structure, combining these PDMS sticks is like closing the zipper of a "freezer bag". This allows easy fabrication of "thin and long" capillary structures containing different reagents inside the same capillary, without the need for precise alignment. This method allows the immobilization of two reactive reagents, such as enzyme and substrate required for a single step assay, which are typically very difficult to immobilize using commercially available conventional capillaries. Furthermore, by simply arraying various CPCs, the CPC sensor allows multiple assays. Here, we carried out a single-step enzyme inhibitor assay using the CPC. In addition, two independent CPCs were arrayed to demonstrate multiple assaying of a protease inhibitor. 相似文献
183.
Horie M Hayashi Y Yamaguchi S Shinokubo H 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(19):5919-5923
Synthesis of nickel(II) complexes of meso-aryl-substituted azacorroles was performed by Buchwald-Hartwig amination of a dipyrrin Ni(II) complex with benzylamine through C-N and C-C coupling. The highly planar structure of Ni(II) azacorroles was elucidated by X-ray diffraction analysis. (1)H?NMR analysis and nucleus independent chemical shift (NICS) calculation on Ni(II) azacorrole revealed its distinct aromaticity with [17]triaza-annulene 18π conjugation. In addition, acylation of azacorrole selectively afforded N- and C-acylated azacorroles depending on the reaction conditions, showing the dual reactivity of azacorroles. 相似文献
184.
Prof. Dr. Masaki Shimizu Yosuke Tomioka Dr. Ikuhiro Nagao Tsugumi Kadowaki Prof. Dr. Tamejiro Hiyama 《化学:亚洲杂志》2012,7(7):1644-1651
(Z)‐1,2‐Diaryl‐1,2‐bis(pinacolatoboryl)ethenes underwent double‐cross‐coupling reactions with 1‐bromo‐2‐[(Z)‐2‐bromoethenyl]arenes in the presence of [Pd(PPh3)4] as a catalyst and 3 M aqueous Cs2CO3 as a base in THF at 80 °C. The double‐coupling reaction gave multisubstituted naphthalenes in good to high yields. Annulation of 1,2‐bis(pinacolatoboryl)arenes with bromo(bromoethenyl)arenes in the presence of a catalyst system that consisted of [Pd2(dba)3] (dba=dibenzylideneacetone) and 2‐dicyclohexylphosphino‐2′,6′‐dimethoxybiphenyl (SPhos) under the same conditions produced fused phenanthrenes in good to high yields. The first annulation coupling occurred regiospecifically at the bromoethenyl moiety. This procedure is applicable to the facile synthesis of polysubstituted anthracenes, benzothiophenes, and dibenzoanthracenes through a double annulation pathway by using the corresponding dibromobis[(Z)‐2‐bromoethenyl]benzenes as diboryl coupling partners. 相似文献
185.
Takasu Y Saito Y Takahashi Y Borkowski M Ciuryło R Julienne PS 《Physical review letters》2012,108(17):173002
We report the successful production of subradiant states of a two-atom system in a three-dimensional optical lattice starting from doubly occupied sites in a Mott insulator phase of a quantum gas of atomic ytterbium. We can selectively produce either a subradiant 1(g) state or a superradiant 0(u) state by choosing the excitation laser frequency. The inherent weak excitation rate for the subradiant 1(g) state is overcome by the increased atomic density due to the tight confinement in a three-dimensional optical lattice. Our experimental measurements of binding energies, linewidth, and Zeeman shift confirm the observation of subradiant levels of the 1(g) state of the Yb(2) molecule. 相似文献
186.
Haiying Fu Yosuke Katsumura Mingzhang Lin Yusa Muroya Kuniki Hata Kentaro Fujii Akinari Yokoya Yoshihiko Hatano 《Radiation Physics and Chemistry》2009,78(12):1192-1197
Two histidine-containing natural dipeptides, carnosine and anserine (β-alanyl-1-methyl-l-histidine), have been examined for their antioxidant and radioprotective abilities. Pulse radiolysis studies indicated the antioxidative properties of carnosine and anserine aqueous solutions at different pH. The rate constants for the reaction OH radical with carnosine at neutral pH were determined to be 5.3×109 M−1 s−1 at 300 nm, and 4.1×109 M−1 s−1 at 400 nm, respectively. Carnosine and anserine also protected plasmid pUC18 DNA from X-ray radiation-induced strand breaks as evidenced from the studies by agarose gel electrophoresis. Carnosine showed higher protective efficiency under the experimental conditions. Our data demonstrated that carnosine and anserine may play an important role in the maintenance of the antioxidant system. 相似文献
187.
Holographic data storage is being widely studied for the purpose of developing next-generation large optical memories. A prospective
use of this type of memory is in building image archives in large-scale data centers. In particular, demand for energy conservation
at data centers, and therefore for holographic data storage, is growing. In holographic data storage, interference between
bits occurs owing to wave aberration in the optical system, shrinkage of the medium, and crosstalk noise from neighboring
holograms during multiplex recording; as a result of the interference, the reproduced image deteriorates and the bit error
rate (BER) increases. In this study, to reduce the BER in both off-axis-type recording and coaxial-type recording, a two-dimensional
finite impulse response (FIR) filter is applied to a reproduced image that has been recorded by angle multiplex recording
and shift multiplex recording. First, for the optimization of the FIR filter coefficients, the linear minimum mean square
error (LMMSE) method is applied; this method optimizes the coefficients by reducing the BER. Furthermore, for evaluating the
optimization performance of the LMMSE method, the optimization performance is compared with that of the real-coded genetic
algorithm (RCGA), which has the capability to search a wide range of coefficients. The optimization by the LMMSE method has
been found to be excellent for off-axis-type recording but not for coaxial-type recording. It is speculated that this is because
of the brightness irregularity in the reproduced image, resulting from crosstalk. On the other hand, a marked reduction in
the BER is observed using the RCGA, despite the brightness irregularity. In this study, the effectiveness of the LMMSE method
for signals recorded by coaxial-type recording, in which large brightness irregularity is expected, is examined using automatic
gain control (AGC). It is found that the application of AGC reduces the BER even in the case of coaxial-type recording. 相似文献
188.
Yosuke Tanaka Tatsutoshi Shioda Takashi Kurokawa Junji Oka Kazuyuki Ueta Toshiharu Fukuoka 《Optical Review》2009,16(3):257-261
We propose a novel power-line-monitoring system using optical fibers for transmitting power as well as signal. The principle
is experimentally confirmed with a system composed of a monitoring side with a 1.5-μm laser diode, transmission line of a
single mode fiber, and a sensing side having an efficient photovoltaic (PV) cell, electrical junction sensor, and low power
liquid crystal optical modulator (LCOM). The PV cell generates the electrical power in the sensing side with a conversion
efficiency of 20%. The LCOM is driven with low power of less than 50 μW, modulates the laser light with a signal indicating
the power line condition, and transmits the optical signal. The developed sensing unit produces an optical signal having an
extinction ratio of 15 dB with low optical power of 1.8 mW. Five systems were in operation for two years, faithfully monitoring
the oil pressure in electrical cables every 20 min without incident. 相似文献
189.
Gianni Ciofani Yosuke Obata Izumi Sato Yosuke Okamura Vittoria Raffa Arianna Menciassi Paolo Dario Naoya Takeda Shinji Takeoka 《Journal of nanoparticle research》2009,11(2):477-484
Mass-produced carbon nanotubes (CNTs) are strongly aggregated and highly hydrophobic, and processes to make them water soluble
are required for biological applications. Both covalent and non-covalent strategies are pursued for obtaining stable, highly
concentrated CNT aqueous dispersions. Covalent functionalization has the great disadvantage of producing an irreversible chemical
modification of nanotubes, thus alterating their mechanical, chemical and electric properties. On the other hand, non-covalent
functionalization is often obtained by employing surfactants that sensibly affect cell viability. Moreover, derivatization
with biological moieties is often impossible through non-covalent CNT dispersion. This paper proposes a non-covalent dispersion
of multi-wall CNT based on a lipidic mixture that can guarantee high concentration and high stability as well as high cytocompatibility.
Moreover, CNTs wrapped with a lipid membrane are realized to demonstrate that the proposed CNTs can be functionalised with
a dodecapeptide that specifically recognizes activated platelets without chemical modification of the nanotube itself. 相似文献
190.