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31.
Jin Y Yamanaka J Sato S Miyata I Yomota C Yonese M 《Chemical & pharmaceutical bulletin》2002,50(10):1341-1348
Hyaluronate-hydroxyethyl acrylate blend gel (HA-PHEA) were prepared to modify the brittleness of hyaluronate gel (HA) and the characteristics of HA-PHEA gel were compared with those of HA and polyhydroxyethyl acrylate (PHEA) gels. These gels were high in water content and transparent. HA-PHEA gel was improved in viscoelastic properties due to the elasticity and the high affinity with water of PHEA, and the drying-swelling cycles became reversible. The effective charge densities theta of the gels estimated from membrane potentials were -0.002, -0.008 and 0 mol dm(-3) for HA-PHEA, HA and PHEA gels. Effects of electro- static and nonelectrostatic interactions on absorptions and releases were studied using sodium benzoate (NaBA) as an anionic solute, and methylene blue (MB), chlorpromazine (CPHCl) and benzethonium chloride (BZTCl) as cationic solutes, in which CPHCl and BZTCl are cationic amphiphilic solutes. The releases of MB, CPHCl and BZTCl from HA-PHEA and HA gels were suppressed comparing with those of NaBA. By adding salts, the releases of MB and CPHCl were enhanced but those of BZTCl were suppressed due to enhancement of the intra- and intermicelle formation. In the releases of the cationic solutes from HA-PHEA gel, electrostatic and nonelectrostatic interactions with HA were found to play important roles. Behaviors of the releases from HA-PHEA gel were found to possess the features of HA gel. 相似文献
32.
A stereocontrolled synthesis of 4′-hydroxymethylated ribo--nucleosides and a new psico--nucleoside has been accomplished on the basis of the [3 + 4] reductive cyclocoupling reaction of α,α,α′,α′-tetrabromoacetone and furfuryl acetate. 相似文献
33.
Watanabe G Umetsu K Yuasa I Sato M Sakabe M Naito E Yamanouchi H Suzuki T 《Electrophoresis》2001,22(3):418-420
We present a simple and rapid polymerase chain reaction (PCR)-based technique, termed consumed allele-specific primer analysis (CASPA), as a new strategy for single nucleotide polymorphism (SNP) analysis. The method involves the use of labeled allele-specific primers, differing in length, with several noncomplementary nucleotides added in the 5'-terminal region. After PCR amplification, the amounts of the remaining primers not incorporated into the PCR products are determined. Thus, nucleotide substitutions are identified by measuring the consumption of primers. In this study, the CASPA method was successfully applied to ABO genotyping. In the present method, the allele-specific primer only anneals with the target polymorphic site on the DNA, so it is not necessary to analyze the PCR products. Therefore, this method is only little affected by modification of the PCR products. The CASPA method is expected to be a useful tool for typing of SNPs. 相似文献
34.
Terai T Araho D Osakabe K Katai M Narama I Matsuura T Katakawa J Tetsumi T Sato M 《Chemical & pharmaceutical bulletin》2000,48(1):142-144
The structure of iso-grayanotoxin II, a new diterpenoid from Leucothoe grayana MAX., has been determined as 3 beta,5 beta,6 beta,14 beta,16 alpha-pentahydroxygrayanotox-9(10)-ene by spectroscopic and X-ray crystallographic analysis. The lethal dosage level of iso-grayanotoxin II in mice was lower than that of grayanotoxin III. 相似文献
35.
36.
37.
T. Sato F. Ambe K. Endo M. Katada H. Sano 《Journal of Radioanalytical and Nuclear Chemistry》1995,190(2):257-261
The crystal structures of oxo-centered trineclear cobalt-iron chloroacetate complex [CoIIFe
2
III
O(CH2ClCO2)6(H2O)3]·3H2O (1) was compared with that of previously reported trinuclear iron complex [FeIIFe
2
III
O(CH2ClCO2)6(H2O)3]·3H2O (2) which has an isomorphous structure to 1. Compound 1 crystallizes in space group P21/n with Z=4 in a unit cell of a=14.826 (4) Å, b=4.536 (8) Å, c=14.000 (4) Å, =100.32 (2)0 and V=2968 (11) Å3. The structure was refined to R=0.75 and Rw=0.82. The coordination geometries of the three iron atoms are observed equivalent in 1 indicating a static disorder of the position among cobalt and iron atoms. Two distinct FeIII doublets observed in Mössbauer spectra of 1 become an indistinguishable broad doublet by dehydration of crystal water. On the other hand, no significant line-broadening is observed after the dehydration in complex 2. The results indicate that the dehydration in 2 induces a local environmental change reordering of an electronic configuration around iron atoms, whereas the remaining disordering is reflected in Mössbauer spectrum after the dehydration in 1. 相似文献
38.
The thermal stress around the sodium level of the LMFBR reactor vessel, caused by the axial temperature distribution during heat-up and cool-down transient conditions, is one of the most important problems for a reactor vessel designer, especially in a conceptual design stage. Key parameters relating to plant operating transient conditions and reactor vessel main configuration should be settled carefully, thermal stresses not being allowed to exceed design stress limits. In order to examine the sodium level thermal stress easily and economically, a simple computer program for parameter survey has been developed. This program uses a one-dimensional Fourier series solution in transient temperature distribution analysis, and an analytical stress solution based on shell theory in stress value estimation. This paper presents a simplified and economical calculation method for the axial temperature distribution and stress value in the LMFBR operating transient conditions, and analysis examples obtained with this computer program.
Paper presented at the World Conference on Thermal Analysis, Madeira (Portugal) 1986. 相似文献
Zusammenfassung Der durch die axiale Temperaturverteilung während der Übergangsphase von Aufheizen und Abkühlen verursachte thermische Streß rund um den Natriumfüllstand des LMFBR-Reaktorkessels ist für den Reaktorkesselkonstrukteur, besonders im Entwurfstadiuni eines der wichtigsten Probleme. Die mit den transienten Operationsbedingungen der Anlage und der Gestaltung des Reaktorkessels in Beziehung stehenden Grundparameter müssen sorgfältig ermittelt werden, um zu verhindern, daß der thermische Streß die geplanten Streßgrenzen nicht überschreitet. Um den thermischen Streß um den Natriumfüllstand, leicht und ökonomisch zu bestimmen, wurde ein Komputerprogramm für die Parameterübersicht aufgestellt. In diesem Programm wird von einer eindimensionalen Fourrierreihe zur Analyse der transienten Temperaturverteilung und einer auf der Schalentheorie von Streßwertbestimmungen basierende analytische Lösung Gebrauch gemacht. Im vorliegenden Artikel werden eine vereinfachte und wirtschaftliche Berechnungsmethode für die axiale Temperaturverteilung und Streßwerte bei transienten Arbeitsbedingungen mitgeteilt und mit diesem Komputerprogramm ausgeführte Analysenbeispiele angegeben.
, - () , , , . , , , . , , - , . , , .
Paper presented at the World Conference on Thermal Analysis, Madeira (Portugal) 1986. 相似文献
39.
T Nishi M Sakurai S Sato M Kataoka Y Morisawa 《Chemical & pharmaceutical bulletin》1989,37(8):2200-2203
An asymmetric synthetic route to 2-substituted-3-aminocarbonyl propionic acid, which is the significant component of low-molecular-weight renin inhibitors, is described. The key step of this synthesis is diastereoselective alkylation by using chiral oxazolidinone and benzyl bromoacetate. 相似文献
40.
E Ohshima T Kumazawa H Takizawa H Harakawa H Sato H Obase Y Oiji A Ishii H Ishii K Ohmori 《Chemical & pharmaceutical bulletin》1991,39(10):2724-2728
A new series of 11-substituted 6,11-dihydrodibenz[b,e]oxepin derivatives was synthesized and evaluated for antiallergic activity. Convenient methods for the preparation of sulfides from alcohols were developed. Structure-activity relationships are described. Compound 7, 11-[2-(dimethylamin)ethyl]thio-6,11-dihydrodibenz[b,e] oxepin-2-carboxylic acid hydrochloride, was the most potent in the rat passive cutaneous anaphylaxis test (ED50 = 0.92 mg/kg p.o.). It had a potent inhibitory effect on anaphylactic bronchoconstriction in guinea pigs (ED50 = 0.029 mg/kg p.o.) and H1 receptor antagonistic effect (Ki = 14 nM) with few central nervous system side effects. Additionally, an antagonistic effect against prostaglandin D2-induced contraction of isolated guinea pig trachea (pA2 = 5.73) was an attractive mechanism of action of the new antiallergic agent. Compound 7 was selected for further evaluation as KW-4994. 相似文献