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排序方式: 共有182条查询结果,搜索用时 46 毫秒
1.
Shunsuke Inenaga Ayumi Shinohara Masayuki Takeda Setsuo Arikawa 《Journal of Discrete Algorithms》2004,2(1):33
Suffix trees are a well-known and widely-studied data structure highly useful for string matching. The suffix tree of a string w can be constructed in O(n) time and space, where n denotes the length of w. Larsson achieved an efficient algorithm to maintain suffix trees for a sliding window. It contributes to prediction by partial matching (PPM) style statistical data compression scheme. Compact directed acyclic word graphs (CDAWGs) are a more space-economical data structure for indexing strings. In this paper we propose a linear-time algorithm to maintain CDAWGs for a sliding window. 相似文献
2.
Arata Yajima Ayumi Yamaguchi Fumihiro Saitou Tomoo Nukada Goro Yabuta 《Tetrahedron》2007,63(5):1080-1084
A convergent synthetic strategy for abietane diterpenoids via B-alkyl Suzuki-Miyaura coupling and Lewis acid-mediated cyclization reactions is established. Asymmetric total synthesis of 12-deoxyroyleanone, an antileishmanial diterpene, is described. 相似文献
3.
4.
Racemic 2-amino-3-(heteroaryl)propanoic acids (1), mostly with a furan or thiophene nucleus as a heteroaryl group, were synthesized in 48-94% yield by the reduction of 3-(heteroaryl)-2-(hydroxyimino)propanoic acids (5) with zinc dust and formic acid in the presence of a catalytic amount of iron dust at 60 degrees C for 2 h. Under these conditions, unfavorable hydrogenolysis of bromine on the thiophene nucleus does not occur. Traditional N-formylation of the prepared 3-(heteroaryl)alanine (1) with a mixture of formic acid and acetic anhydride afforded 2-(formylamino)-3-(heteroaryl)propanoic acids (6) in 51-95% yield. 相似文献
5.
Antioxidant activity of a series of hydroxybenzalacetones was determined against peroxynitrite-induced lipid peroxidation in red blood cell membrane and SOS response through DNA damage in bacterial cells. Hydroxybenzalacetone derivatives with hydroxy, methoxy, ethoxy or methyl substitution were analyzed and found to be more effective than the water-soluble vitamin E analogue Trolox. The inhibitory effect against lipid peroxidation correlated well to that against the SOS response, which is dependent on decomposition of peroxynitrite by hydroxybenzalacetones outside of the cell membrane. The antioxidant activity was shown to correlate well with the electric parameter sigma+. Electron-donating substituents with more negative sigma+ values increased the potencies. The result suggests that hydroxybenzalacetones with more electron-donating substituents will protect tissue more effectively against oxidative stress. 相似文献
6.
Phylogenetic analysis of picoplankton in Lake Biwa and application to legal medicine 总被引:1,自引:0,他引:1
Three strains of picoplankton designated as brown, green, and pink belonging to the Synechococcus genus in cyanobacteria (approximately 1 microm in size) are found ubiquitously in Lake Biwa, Japan. However, they could not be morphologically discriminated from other bacteria such as Proteobacteria and Bacillus by microscopy. In this study, we attempted to use the polymerase chain reaction (PCR) analysis of the 16S ribosomal DNA (rDNA) from picoplankton for the diagnosis of death by drowning. A segment of 16S rDNA was sequenced in order to investigate their phylogenetic relationships and to design the specific primers. The PCR products from three picoplanktons were compared with those from five other cyanobacteria, Melosira (diatom), Staurastrum (green alga), bacteria from Lake Baikal, and humans. The picogram order of template DNA from picoplankton was specifically amplified by the primers. When the template of picoplankton was mixed with human tissue, at least 10 ng of template DNA was needed to obtain a PCR product. The efficiency of PCR was increased more than hundredfold by isolating the picoplankton from human lung tissue. The specific PCR products of the picoplankton were obtained from a formalin-fixed drowning body (lung and liver) that was found in a downstream river and Lake Biwa. The PCR analysis of the picoplanktion 16S rDNA is considered useful for the diagnosis of death by drowning. 相似文献
7.
Kenjiro Hattori Tomoko Takeuchi Mika Ogata Ayumi Takanohashi Katsuhiko Mikuni Katsuyoshi Nakanishi Hideo Imata 《Journal of inclusion phenomena and macrocyclic chemistry》2007,57(1-4):339-342
We obtained the association constants Ka of estrogen (E2) and environmental chemicals by the surface plasmon resonance (SPR) assay using the immobilized mono-6-O-α-maltosyl-β-CD (G2βCD) compared with the immobilized β-CD and the immobilized estrogen receptor (ER). The association behavior of G2βCD was shown as a ER model compound. The calibration curve was determined by the initial rate of association depending on
the various concentrations, and the minimum detectable concentrations in the order of parts per billion were calculated. The
SPR assay has advantages that the pre-treatment of the sample is not necessary and the immobilized ligand is stable and useful
for the repeated measurement. 相似文献
8.
Kobayashi J Sekiguchi M Shimamoto S Shigemori H Ishiyama H Ohsaki A 《The Journal of organic chemistry》2002,67(18):6449-6455
Three novel quaternary indole alkaloids with an unprecedented 1-azoniatricyclo[4.3.3.0(1,5)]undecane moiety, subincanadines A-C (1-3), as well as two new indole alkaloids with a 1-azabicyclo[5.2.2]undecane moiety, subincanadines D (4) and E (5), and a new indole alkaloid with a 1-azabicyclo[4.3.1]decane moiety, subincanadine F (6), have been isolated from the barks of Aspidosperma subincanum Mart, and the structures of 1-6 and the stereochemistry of 1-3 were elucidated by spectroscopic data and chemical means. 相似文献
9.
10.
Ayumi Yoshida Hitoshi Yamauchi Hideki Sakai Norimichi Kawashima Masahiko Abe 《Colloids and surfaces. B, Biointerfaces》1997,8(6):191-342
Molecular interactions between lipid bilayers (liposomes) and chondroitin sulfate C (CS), a water soluble polymer, have been investigated in terms of zeta-potential, particle size, microscopic-viscosity, microscopic-polarity of liposomes and permeability of calcein. Microscopic morphology is dramatically changed by the addition of CS to the positively charged liposomes (Pos.L), while it is not changed by the addition to uncharged liposomes (Unc.L) or negatively charged liposomes (Neg.L). The absolute value of the particle size of Pos.L increases with the addition of CS, while the zeta- potential of Pos.L decreases. Permeability of Pos.L decreases with an increase in the concentration of CS. Phase transition temperature of Pos.L is changed after the addition of CS. These values, however, are not changed for the other liposomes by the addition of CS. The results of gel filtration chromatography show that CS is absorbed on the Pos.L surface. Microscopic viscosity is also increased by the addition of CS to Pos.L due to the adsorption of CS. 相似文献