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排序方式: 共有270条查询结果,搜索用时 15 毫秒
251.
Chunxia Zhao Arivazhagan Rajendran Qing Dai Seiichi Nishizawa Norio Teramae 《Analytical sciences》2008,24(6):693-695
A fluorescent pyrazine derivative, 3,5-diamino-6-chloro-2-pyrazine carbonitrile (DCPC), is presented as a promising light-up ligand for single-nucleotide polymorphisms (SNPs) typing. In solutions buffered to pH 7.0 (I = 0.11 M, at 5 degrees C), DCPC can bind to thymine selectively over other nucleobases opposite an abasic site in DNA duplexes (5'-GTGTG CGTTG ANA TGGAC GCAGA-3'/3'-CACAC GCAAC TXT ACCTG CGTCT-5', X = abasic site, N = target nucleotide) with a dissociation constant of 2.6 microM. The binding of DCPC is accompanied by a significant enhancement of its fluorescence (lambda(max), 412 nm), and the response is highly selective to thymine base. These binding and sensing properties allow a clear detection of thymine-related mutations present in polymerase chain reaction (PCR) amplification products. 相似文献
252.
Takeshi Arai Shuichi Obuchi Motonaga Kojima Satoshi Nishizawa Yuko Matsumoto Yasuko Inaba 《Physical Therapy Research》2009,12(1):1-8
The purposes of this study were to evaluate the relationship between age and changes in physical measurements after exercise intervention and to investigate the trainability of the older elderly. Two hundred seventy-six community-dwelling people aged 60 years and older practiced exercise intervention for 3 months. The measurements of physical functions were one-legged standing with eyes open and closed (OLS-O, OLS-C), functional reach test (FR), timed up and go test (TUG), maximum walking velocity, flexibility, and muscle strength. We evaluated the associations between age and the changes in these physical measurements. All measurements except for OLS-C significantly improved after intervention. The magnitude of the changes in hand-grip strength and FR after the intervention showed weak negative correlations with the subject''s age, but other measurements showed no correlations. In addition, there were no differences between younger elderly persons and older elderly persons with regard to changes in any measurements. These results suggested that the exercise intervention we applied could improve physical fitness in community-dwelling older people, regardless of their age. The older elderly were comparable to the younger elderly in trainability to improve physical fitness. 相似文献
253.
K. Kamiyama D. Shiomi S. Hase M. Nishizawa K. Sato M. Kozaki K. Okada T. Takui 《Applied magnetic resonance》2000,19(1):45-57
A crystal-engineering approach to organic ferrimagnets is reported. Coulombic energy between an anionic biradical withS = 1 and a cationic monoradical withS = 1/2 can be utilized as a driving force of cocrystallization of open-shell molecules with different spin quantum numbers,
leading to organic salt ferrimagnets. In this study, 3,5-substituted phenol and benzoic acid derivatives of nitronyl nitroxide
biradicals were synthesized as an ionizableS = 1 component of organic salt ferrimagnets. The molecular ground states of the biradicals in the neutral state were examined
by continuous wave electron spin resonance (ESR) spectroscopy and static paramagnetic susceptibility measurements in the solid
state. The molecular ground state of the phenol derivative was found to be triplet (S = 1) with the singlet-triplet energy gap of ΔE/kB ≈ 25 K, indicating that the biradical can be a building block of organic salt ferrimagnetics. The benzoic acid derivative
was found to have a singlet (S = 0) ground state (ΔE/kB
≧ −5 K), exemplifying thatmeta-(3,5)-linkage of unpaired electrons in π-aromatic rings does not necessarily give a triplet ground state for heteroatomic-substituted
π conjugation. The molecular ground states of the biradicals determined in the ESR experiments were confirmed by the susceptibility
in the solid state. 相似文献
254.
Harinantenaina L Takahara Y Nishizawa T Kohchi C Soma G Asakawa Y 《Chemical & pharmaceutical bulletin》2006,54(7):1046-1049
3Beta,4beta:15,16-diepoxy-13(16),14-clerodadiene (1) and a new clerodane diterpenoid designated thysaspathone (2) were isolated from the liverwort Thysananthus spathulistipus, while Radula appressa produced radulannin A (3), radulannin L (4), 2-geranyl-3,5-dihydroxybibenzyl (5), 2(S)-2-methyl-2-(4-methyl-3-pentenyl)-7-hydroxy-5-(2-phenylethyl) chromene (o-cannabichromene) (6), 6-hydroxy-4-(2-phenylethyl) benzofuran (7), and o-cannabicyclol (8). All of the isolated compounds inhibited nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells and the greatest inhibition was attributed to compound 5, with an IC50 value of 4.5 microM. 相似文献
255.
Dai J Bai J Hasegawa T Nishizawa S Sakai J Oka S Kiuchi M Hirose K Tomida A Tsuruo T Li M Ando M 《Chemical & pharmaceutical bulletin》2006,54(3):306-309
A new taxoid, 5alpha,13alpha-diacetoxy-10beta-cinnamoyloxy-4(20),11-taxadien-9alpha-ol (1) along with its 9,10-isomer, taxinine NN-11 (2) were isolated from the callus cultures of Taxus cuspidata. The structures were identified by the analyses of the spectral data and chemical method. Their in vitro cytotoxicity against 3 cell lines (HepG2, WI-38 and VA-13) and multidrug resistance (MDR) reversal activity toward 2780AD tumor cells were preliminarily evaluated, the low cytotoxicities and potent MDR reversal activities suggested that they might be good lead compounds of tumor MDR reversal agent. 相似文献
256.
Michitomo Nishizawa 《Letters in Mathematical Physics》1996,37(2):201-209
A q-analogue of the multiple gamma functions is introduced and is shown to satisfy the generalized Bohr-Morellup theorem. Furthermore, we give some expressions of these functions. 相似文献
257.
Tahara K Abe Y Sugata S Nishizawa H Nishikawa T Suzuki H Takeuchi M 《Journal of chromatography. A》2003,1017(1-2):63-69
An improved apparatus for solid-liquid multi-stage counter-current extraction (SLME) was developed. The apparatus has a set of 24 extraction vessels. Each extraction vessel unit is composed of a piston-cylinder in which the solid phase is placed, and a cup-cylinder in which the liquid phase is set. Of the 24 extraction vessels, 20 were used for the separation stage, and the other 4 were used for the back-extraction stage. (+/-)-Troger's base was selected as a racemic model compound for the continuous enantioseparation by the apparatus, and a cellulose derivative was used as the chiral separator. After 50 cycles of the operation (in 9 h), 0.1 g of (-)-enantiomer (85% in purity) was recovered from the solid phase by back-extraction with ethanol, whereas 1.1 g of (+)-isomer (75% in purity) was collected from the liquid phase (ethanol). 相似文献
258.
A convenient procedure for the synthesis of deuterium labeled terpenic alcohols of high optical purity is described. 相似文献
259.
Y. Nakamura T. Kashiwagi S.L. Olson K. Nishizawa O. Fujita K. Ito 《Proceedings of the Combustion Institute》2005,30(2):2319-2325
Numerical computations and a series of experiments were conducted in microgravity to study the ignition characteristics of a thin polymethylmethacrylate (PMMA) sheet (thicknesses of 0.2 and 0.4 mm) using a CO2 laser as an external radiant source. Two separate ignition events were observed, including ignition over the irradiated surface (frontside ignition), and ignition, after some delay, over the backside surface (backside ignition). The backside ignition was achieved in two different modes. In the first mode, after the laser was turned off, the flame shrank and stabilized closer to the fuel surface. This allowed the flame to travel from the frontside to the backside through the small, open hole generated by the laser’s vaporization of PMMA. In the second mode, backside ignition was achieved during the laser irradiation. The numerical calculation simulating this second process predicts fresh oxygen supply flows from the backside gas phase to the frontside gas phase through the open hole, which mixes with accumulated hot MMA fuel vapor which is ignited as a second flame in the frontside gas phase above the hole. Then, the flame initiated from the second ignition travels through the hole to ignite the accumulated flammable mixture in the backside gas phase near the hole, attaining backside ignition. The first backside ignition mode was observed in 21% oxygen and the second backside ignition mode in 35%. The duration of the laser irradiation appears to have important effects on the onset of backside ignition. For example, in 21% oxygen, the backside ignition was attained after a 3 s laser duration but was not observed after a 6 s laser duration (within the available test time of 10 s). Longer laser duration might prevent two-sided ignition in low oxygen concentrations. 相似文献
260.
Adi Rahwanto Rintaro Nomura Norihiko Nishizawa Toshio Goto Masakazu Mori Kazuo Yamane 《Optical Review》1998,5(1):5-8
A new scheme of an amplitude modulated harmonically mode-locked Er-doped fiber ring laser is proposed, and the lasing characteristics are experimentally investigated. The transform-limited sech2 pulses at the repetition frequency of 1.64 GHz are stably generated. The pulse width and spectral bandwidth are independent of both the amplitude modulated (AM) modulation signal frequency and the AM modulation depth. 相似文献