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91.
The model rat for the type 2 diabetes mellitus (NIDDM) in human were observed for 72 weeks after birth, administering an organic germanium compound [Bis(2-Carboxyethyl) germasesquioxane, Ge-132] perorally 100 mg/kg/day since 24 weeks old. Clinical examinations were followed throughout the observation period. Blood and urinary glucose in positive control OLETF rats tended to be higher than those treated with Ge-132. At the end of the 72nd week, animals were sacriificed to examine the pathological changes, specifically in pancreas, kidney and brain. Anti-AGE antibody stained proximal and distal tubles and basement membrane of glomerules in kidney, and accumulated AGE masses in cortex, hippocampus and cerebellum of OLETF rat's brain. Amyloid stains by basic congo red on kidney and brain revealed that the deposits of amyloid in kidney mesangium and in cortex, hippocampus and cerebellum were observable in OLETF rats. Ge-132 suppressed the deposition of amyloid tangles in kidneys and brains. Anti rat complement C'3 antibody reacted with AGE and amyloid tangles that were sensitive to anti-AGE antibody. AGE generated in vitro by incubating human serum, human gammaglobulin (HGG), or bovine serum albumin (BSA) with glucose activated complements, showing the consumption of complements in the hemolysis of hemolysin-coated sheep red blood cells. A novel device Quantum Resonance Spectrometer (QRS) could read the subtle bio-magnetism memorized in serum samples, demonstrating quantitative values reflecting the patho-physiology of OLETF rats.  相似文献   
92.
In the previous paper (N. Kanazawa, K. Urano, N. Kokado, Y. Urushigawa, J. Colloid Interface Sci. 238 (2001) 196), the equilibria of propionic acid and benzoic acid adsorption onto three anion-exchange resins were investigated, and an equation was proposed that summed of the physical adsorption of the carboxylic acid molecule and the ion exchange of the dissociated carboxylate ion. The ion exchange equation, including a selectivity coefficient to chloride ion for each combination between carboxylate ions and anion-exchange resins, could be used in wide ranges of concentration and pH. In this research, ion-exchange equilibria using 16 anion-exchange resins and 9 organic acids including monocarboxylic and monosulfonic acids were investigated. It could be confirmed that the proposed equation applied to the ion exchange with these monoorganic acids. Characteristics of ion exchange between the organic anions and anion exchange were also studied by the selectivity coefficients.  相似文献   
93.
Kuroda R  Yoshikuni N 《Talanta》1971,18(11):1123-1127
Many metals are not strongly adsorbed on DEAE-cellulose from aqueous hydrochloric acid media. However, some metals can be adsorbed on DEAE-cellulose from methanol-hydrochloric acid media. Distribution coefficients of Zn, Cd, Hg(II) and Bi(III), which show pronounced adsorption, are presented as functions of the methanol and the acid concentrations. Differences in the distribution coefficient between the four metals and a considerable number of other metals are large enough to permit good separations on columns. Among the platinum group metals, Pd(II), Ir(IV) and Pt(IV) are adsorbed from the mixed solvents and may be separated from large quantities of base metals such as Fe(III), Co(II), Ni and Cu(II).  相似文献   
94.
IPN-type composites consisting of cellulose acetate (CA) and poly(methyl methacrylate; PMMA) were successfully synthesized in film form. In this synthesis, a mercapto group (SH)-containing CA, CA-MA, was prepared in advance by esterification of CA with mercaptoacetic acid, and then intercomponent cross-linking between CA-MA and PMMA was attained by thiol–ene polymerization of methyl methacrylate (MMA) onto the CA-MA substrate. For comparison, polymer synthesis was also attempted to produce a semi-IPN type of composites comprising CA and cross-linked PMMA, via copolymerization of MMA and ethylene glycol dimethacrylate as cross-linker in a homogeneous system containing CA solute. Thermal and mechanical properties of thus obtained polymer composites were investigated by differential scanning calorimetry, dynamic mechanical analysis, and a tensile test, in correlation with the mixing state of the essentially immiscible cellulosic and methacrylate polymer components. It was shown that the specific IPN technique using thiol–ene reactions usually resulted in a much better compatibility-enhanced polymer composite, which exhibited a higher tensile strength and even an outstanding ductility without parallel in any film sample of CA, PMMA, and their physical blends.  相似文献   
95.
Blood levels of the vitamin D3 (D3) metabolites 25-hydroxyvitamin D3 (25(OH)D3), 24R,25-dihydroxyvitamin D3, and 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3) are recognized indicators for the diagnosis of bone metabolism-related diseases, D3 deficiency-related diseases, and hypercalcemia, and are generally measured by liquid-chromatography tandem mass spectrometry (LC-MS/MS) using an isotope dilution method. However, other D3 metabolites, such as 20-hydroxyvitamin D3 and lactone D3, also show interesting biological activities and stable isotope-labeled derivatives are required for LC-MS/MS analysis of their concentrations in serum. Here, we describe a versatile synthesis of deuterium-labeled D3 metabolites using A-ring synthons containing three deuterium atoms. Deuterium-labeled 25(OH)D3 (2), 25(OH)D3-23,26-lactone (6), and 1,25(OH)2D3-23,26-lactone (7) were synthesized, and successfully applied as internal standards for the measurement of these compounds in pooled human serum. This is the first quantification of 1,25(OH)2D3-23,26-lactone (7) in human serum.  相似文献   
96.
Silica-pillared clays were prepared by reacting Na-montmorillonite aqueous suspensions with (3-aminopropyl)triethoxysilane (APTEOS). It was indicated that cubic octamers [NH3+(CH2)3SiO3/2]8 derived from APTEOS are intercalated with two different conformations of the alkyl chains. Namely, the cubic octamers are intercalated with the alkyl chains parallel to the silicate layers at low concentration of APTEOS, and then intercalated with the alkyl chains normal to the silicate layers with increase in APTEOS. Gels were prepared from the reaction of APTEOS with acetic acid and by the conventional sol-gel process using (3-aminopropyl)trimethoxysilane (APTMOS). The luminescence spectra of the gel prepared by the sol-gel process and the intercalated clays were similar to that of silica gels. The gel from APTEOS with acetic acid showed broad visible luminescence. The luminescence spectra and the structures of these materials were described.  相似文献   
97.
Regioselective and high-yielding nuclear monobromination of aromatic ethers can be accomplished with a combination of NaClO2, NaBr, and Mn(acac)3 catalyst in dichloromethane under mild and neutral conditions with the aid of Montmorillonite K10.  相似文献   
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