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101.
102.
H Ikeda Y Shimonishi M Ohmura K Kishimoto K Kosakai K Hamada H Ochi 《Radioisotopes》1990,39(11):487-492
Textural features for phantom images were extracted. Texture parameters which represent RI distribution--skew, energy, entropy and angular second moment were used. But, it was difficult to analyse the images using discriminant analysis for textural features, because textural features had statistical noise. Therefore fuzzy reasoning was adapted to analyse the images. Textural features for six kinds of images were showed using membership function. The possibility to the image was evaluated using the value of membership function on each images. Fuzzy reasoning could be done easily using max-min composition formula. The reasoning was found more suitable to analyse the images than discriminant analysis and will be considered useful for analysis of clinical scintigrams. 相似文献
103.
Hosaka S Sato M Ozawa Y Hamada C Takahashi Y Kitamori N 《Chemical & pharmaceutical bulletin》2005,53(5):503-507
Manidipine dihydrochloride or benidipine hydrochloride will change to hydrate form in part, when differential scanning calorimetric (DSC) measurement is carried out together with lactose monohydrate. This interaction was accelerated by compressing their mixture. It can be suggested that the interaction may cause by the disruption of crystal structure of lactose monohydrate due to compression to set free of water molecules. A new DSC peak at 170 degrees C, which was not observed in each component, appeared in DSC measurement of a mixture. This will be based on hydrate formed by the interaction, i.e., movement of water molecules. The profile of the plotting of the DSC peak area ratio before and after compression against the compression force changed by the molar ratio of lactose monohydrate in a mixture. In the case of low molar ratio of lactose monohydrate, profiles for manidipine dihydrochloride and benidipine hydrochloride differed from each other. This will be because manidipine dihydrochloride is stickier than benidipine hydrochloride. The profile for manidipine dihydrochloride became more gradual and showed lag compression force region when the amount of addition of the lubricant, magnesium stearate in a mixture increased. The endothermic peak area at 170 degrees C for manidipine dihydrochloride was larger than that for benidipine hydrochloride. It should be suggested that benidipine hydrochloride is easier to be transformed to its hydrate than manidipine dihydrochloride. 相似文献
104.
Matsuura K Ikoma S Sugiyama M Funauchi M Sinohara H 《Applied biochemistry and biotechnology》2000,83(1-3):107-114
Polyclonal Immunoglobulin (Ig) G from patients with rheumatoid arthritis (RA) and healthy subjects hydrolyzed carbobenzoxy−Val−Gly−Arg
p-nitroanilide and D−Pro−Phe−Arg p-nitroanilide. RA IgG exhibited higher activity against the former substrate, but not the latter. On the other hand, RA IgG
showed reduced activity against D−Pro−Phe−Arg methylcoumarinamide, when compared with those of the healthy controls. These
results suggest that RA IgGs differ from normal IgGs in the substrate specificity of amidase activity. Preliminary studies
have shown that two out of three RA IgG samples cleaved a pentapeptide—Gln−Arg−Arg−Arg−Ala−Ala— which is assumed to be associated
with the risk of developing RA (Gregersen, P. K. et al. (1987), Arthritis Rheum.
30, 1205–1213). By contrast, virtually no cleavage of the same peptide was observed with IgG from healthy controls. A peptide
analog, Gln−Arg−Arg−Trp−Ala, was not cleaved at all by any IgGs examined either from RA patients or healthy controls. 相似文献
105.
Alkylation‐, Heating‐, and Doping‐Induced Emission Enhancement of a Polyaromatic Tube in the Solid State 下载免费PDF全文
Kiyonori Kuroda Masafumi Otsuki Dr. Kohei Yazaki Dr. Yoshihisa Sei Prof. Dr. Munetaka Akita Dr. Michito Yoshizawa 《化学:亚洲杂志》2018,13(5):515-519
A polyaromatic tube with a subnanometer‐sized cavity was efficiently prepared on a gram‐scale through the stereo‐controlled cyclotrimerization of a diphenylanthracene derivative as a key step. The facile exterior alkylation of the polyaromatic framework leads to a moderately fluorescent tube (R=‐OC10H21; ΦF=20 %) in the solid state. The emission intensity of the solid‐state alkyl‐substituted tube is remarkably enhanced upon heating (up to 1.6 times, ΦF=31 %) as well as doping with fluorescent dyes (up to 4.2 times, ΦF=83 %) through efficient energy transfer. 相似文献
106.
Shinichi Shimizu Hideaki Hamada 《Angewandte Chemie (International ed. in English)》1999,38(18):2725-2727
Using a quartz glass tube as a bulk silica source under aqueous hydrothermal conditions afforded giant crystals of MFI zeolite about 3 mm in size (see photo). Similar procedures were successfully applied to bulk aluminosilicate ceramics to synthesize large crystals of other zeolites, such as ANA, JBW, CAN, and SOD. 相似文献
107.
M Horie K Saito Y Hoshino N Nose N Hamada H Nakazawa 《Journal of chromatography. A》1990,502(2):371-378
A simple and selective method for the determination of sulphamethazine (SMT) and its metabolite, N4-acetylsulphamethazine (N4-AcSMT), in meat by high-performance liquid chromatography (HPLC) with photodiode-array detection was developed. The drugs were extracted from meat with 0.2% metaphosphoric acid-methanol (6:4), followed by a Bond-Elut C18 clean-up procedure. The HPLC separation was carried out on a Supersphere RP-18e column (125 X 4.0 mm I.D.) using 0.05 M sodium dihydrogenphosphate (pH 4.5)-acetonitrile (8:2) as the mobile phase at a flow-rate of 0.5 ml/min, and monitored with a photodiode-array detector. The recoveries of SMT and N4-AcSMT from meat fortified at 0.5 micrograms/g were 90.1-93.3 and 93.0-94.4%, respectively, with coefficients of variation of 1.9-3.2 and 1.5-2.7%. The limits of detection were 0.02 micrograms/g for each drug. SMT was found in ten samples of imported meat (12.5%) at levels ranging from 0.05 to 1.05 micrograms/g. 相似文献
108.
109.
Keinosuke Hamada 《Journal of Molecular Structure》1978,48(2):191-197
The Raman and IR spectra of hexachlorodisilazane were measured, and the assignment carried out by comparison with those of the structurally related compounds, hexachlorodisiloxane, hexachlorodisilane and dimethylamine. The vibrational spectra of hexachlorodisilazane are very closely related to those of hexachlorodisiloxane, hexachlorodisilane and dimethylamine, and can be interpreted in terms of a non-rigid D3d symmetry with an internal rotation. 相似文献
110.
Shoji T Higashi J Ito S Okujima T Yasunami M Morita N 《Organic & biomolecular chemistry》2012,10(12):2431-2438
Arylethynyl-2H-cyclohepta[b]furan-2-ones reacted with 7,7,8,8-tetracyanoquinodimethane (TCNQ) in a formal [2 + 2] cycloaddition reaction, followed by ring opening of the initially formed cyclobutene derivatives, to afford the corresponding dicyanoquinodimethane (DCNQ) chromophores in excellent yields. The intramolecular charge-transfer (ICT) interactions between the 2H-cyclohepta[b]furan-2-one ring and DCNQ acceptor moiety were investigated by UV/Vis spectroscopy and theoretical calculations. The redox behavior of the novel DCNQ derivatives was examined by cyclic voltammetry (CV) and differential pulse voltammetry (DPV), which revealed their multistep electrochemical reduction properties depended on the number of DCNQ units in the molecule. Moreover, a significant color change was observed by visible spectroscopy under electrochemical reduction conditions. 相似文献