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国立情報学研究所で電子化したコンテンツを使用している。

国立情報学研究所で電子化したコンテンツを使用している。

国立情報学研究所で電子化したコンテンツを使用している。

国立情報学研究所で電子化したコンテンツを使用している。

国立情報学研究所で電子化したコンテンツを使用している。

国立情報学研究所で電子化したコンテンツを使用している。

国立情報学研究所で電子化したコンテンツを使用している。

Traditionally in Japan, some kampo medicines (traditional oriental herbal prescriptions) have long been used for the treatment of diabetic neuropathy. We have found that some aldose reductase inhibitors are included among these drugs. We further investigated the components of glycyrrhizae radix, a constituent of some kampo medicines, and isolated six compounds (GUs 9-17). Among these, GU-17, identified as isoliquiritigenin, had the most potent aldose reductase inhibiting activity. Isoliquiritigenin inhibited rat lens aldose reductase with an IC50 of 3.2 x 10(-7) M, using DL-glyceraldehyde as a substrate. It inhibited sorbitol accumulation in human red blood cells in vitro, with an IC50 of 2.0 x 10(-6) M. Isoliquiritigenin, when administered via an intragastric tube to diabetic rats, suppressed sorbitol accumulation in the red blood cells, the sciatic nerve, and the lens as effectively as ONO-2235. These results suggest that isoliquiritigenin may be effective in preventing diabetic complications.

2010年12月1日 : 増補版(2010年3月15日発行)追加

新制名古屋大学の包括学校;3

In this paper we describe an experimental study, reported in this article are trial manufacture of composite tooth material from unsaturated polyester as matrix and feldspar as filler and results of experimental studies in its mechanical properties, abrasion properties and cross linking effect by radiant rays, etc. As a result of this series of tests and experiments, it was found that, as filler ratio increases, composite dental material of U.P./ feldspar increases in elastic modulus but decreases in tensile strength, bending strength, elongation and deflection. Abrasion resistance becomes remarkably stronger as filler ratio becomes bigger. No radiation cross linking effects are expected. Material having feldspar by about 25% can be expected to be composite dental material.

In this study we investigated the tensile characteristics of welded polycarbonate at low temperature. This study intends to clarify the low temperature characteristics of welded part comparing with those of base material. The results of some measurements on the tensile properties from 20°C down to -70℃ are reported and the changes in tensile properties under low temperature atmosphere are discussed. Furthermore, notch and load velocity effects on the brittle fracture tendency are also discussed. Conclusions obtained in this study are summarized as follows; 1) Both welded part and base material of polycarbonate are strengthened at low temperature. 2) Welding joint efficiency of polycarbonate is very good even at low temperature. 3) Notch and load velocity effects are observed both on the base and the welded materials. 4) Correlations are observed between fracture surfaces and mechanical testing results.

In this paper we describe an experimental study. Reported in this article are results of tensile fatigue test under constant stress amplitude applied to bonded section of carbon fiber reinforced dental P.M.M.A., which tensile fatigue test was conducted in comparison with that of the parent material in order to find out fatigue characteristics of the bonded section of the dental P.M.M.A. As a result of the research of test and experiments, it is found that; 1) It is noted that fatigue characteristics of composite material of C.F. 1 wt.%/P.M.M.A. are good. 2) For adhesion of composite material of C.F. 1 wt.%/P.M.M.A., a scarf joint should be adopted. 3) Adhesion by heat-cured type acrylic resin is effective.

In this paper we describe an experimental study. Studied in this article is resistance against impact load applied to bonded part of dental hot curing type acrylic resin teeth in oral cavity, acrylic resin base, etc. As a result of the research of test and experiments, it is found that; Scattering in impact values of adhered materials was little. Impact strength increased as temperature of atmosphere rose. Approximation of adhesion joint efficiency in terms of impact strength was 70% and 40% with hot and coid curing types acry1ic resin respectively, and hot curing type adhesive was superior. Observation by scanning type electron microscope revealed that impact fracture of the base material and that of the material adhered by hot curing type adhesive were similar and that the breaking was ductile, the failure of the material adhered by cold curing type adhesive was accompanying breaking-away on adhesion interfact.

Reported in this article are results of experiment in which diand tri-methacrylic acid esters and di- and tri-allyl compounds are used as cross linking monomer to coat P.M.M.A., irradiated with radioactivity to bring about linking reaction and improvement in linking density, so that the abrasion resistance of the dental P.M.M.A. can be improved. It was found that to add diallyl compound to unsaturated polyester and to coat the material with curing catalyzer as coating material added with M.E.K.P.O. and naphthenic acid cobalt and to irradiate with radioactivity to enrich cross linking density after hot press processing were very effective as a treatment to improve abrasion resistance of dental P.M.M.A ..

In this paper we describe an experimental study on the characteristics at low temperature of welded low density polyethylene. That is to say, we report the results of some measurments on the mechanical properties, fractured surfaces, x-ray diffraction patterns and electron spin resonace spectra, and discuss them in this paper.

In this paper we describe an experimental study. This article is a trial production of carbon fiber reinforced anisotropic polymer composite materials of very thin plate sandwich structure consisting of polymer single plate as core and fiber reinforced very thin single plate with X-Y surface anisotropy adhered to each other in optional orientation angle. Bending and tensile characteristics of their mechanical properties are also clarified in this article. It was found that the following; 1) Regarding bending: Calculated value of bending elastic modulus of C.F. prepreg 6 ply, C.F./P.M.M.A./C.F. sandwich and sandwich are similar each other. Material effect of sandwich structure is better than that of C.F. structure. Bending elastic modulus is greatly influenced by orientation angle. 2) Regarding tension: Sandwich structure is inferior to C.F. structure with regard to tensile strength and Young's modulus. Sandwich structure is not effective against tension. Experimental value and calculated value of sandwich structure were similar. Both of strength and elastic modulus are greatly influenced by orientation angle.

In this paper we describe an experimental study, this article is to report fundamental data of constructions attained by carbon fiber reinforced hybrid composite of O.9mm in thickness whose resin base was reinforced. As a result of this series of test and experiments, it was found that; it is possible to attain reinforced resin base of hybrid composite of C.F.R.P. 16 times as much in rigidity against bending load as compared with that of single construction was observed with composite of O.9mm lamina. It was found that sandwich construction of C.F.R.P. is superior, while, in the case of canape construction, it was found necessary to have C.F.R.P. on the tension side. G.F.R.P. has possibility to be reinforced composite material, although it is considerably less superior to C.F.R.P.

In this paper we describe an experimental study. Reported in this article are tensile fatigue characteristics of polymethylmetacrylate and its bonded material in relation to wave form of load, loading velocity and notch effect. In experiments, heat cured acrylic resin was used for base material, while heat cured and self-cured polymethylmetacrylate (Denture Acrylic SHOFU "Bio" Resin) were used as Adhesives. As a result of the research of test and experiments, it is found that; 1) Fatigue limits of the bonded materials using heat cured and self-cured P.M.M.A. are approximately 2/3 and 1/3 of that of the base material. 225 2) Two-fold property of S-N curve can be seen with dental P.M.M.A., and such property is partly attributable to temperature rise of the test piece. Fatigue limit drops as test velocity increases, and such drop is again partly attributably to temperature rise of the material. 3) Effect of notch is observed and it is noted that the notch causes deterioration in endurance limit by about 1/4.

In this paper we describe an experimental study on the environmental deterioration of dental polymethyl methacrylate bonded parts. As a result of this series of test and experiments, it was found that no big difference was found in terms of tensile strength, bending strength and electron microphotography with regard to the base material and the bonded materials after deterioration by weather and by calciumphosphate-glycerine. Roughness of the surface became a little finer after deterioration.

In this paper we describe an experimental study. In this article discussed is abrasion resistance of the compound teeth which are intended to complement defects of porcelain teeth and those of resin teeth each other. Namely, compound teeth were made from P.M.M.A. porcelain powder and raw materials for porcelain teeth. These teeth were subjected to rotation abrasion test to find out abrasion resistance and to clarify effectiveness of compound teeth made from organic and inorganic materials. It was found that the following; 1) It has been found that compound teeth of P.M.M.A. with 10 wt.% feldspar powder has excellent abrasion resistance from practical point of view. 2) It is possible to make compound teeth having abrasion resistance about 10 times as much of P.M.M.A. teeth.

In this paper we describe an experimental study on the irradiation effect of 60Co-γ ray for dental P.M.M.A. welding parts, hot polymerizing adhesion parts and cold polymerizing adhesion parts. As a result of this series of test and experiments, it was found that from the result of tension test, no remarkable change is found with any of the bonded materials by the irradiation dose up to 10' r., and no deterioration by irradiation is observed. And then, according to the results of bending test, it is found that, although the three different bonded materials have different features, high strength of the welded material and of the material adhered by hot polymerizing adhesive becomes lower by irradiation, and strength of the three materials converges after irradiation within the range of 10 6 -10 7 r.. Joint efficiency of 65-75 % in tension and 50-62 % in bending can be adopted. With regard to fracture, blocks of each specimen are finely divided and show tendency of becoming brittle by irradiation. Fracture of the base material and of the bonded materials are similar and prove bonding of high strength.

In this paper we describe an experimental study, in the preceding article, authors reported about the weldabilities of pOlypropylene 1) , polyamide 2), polyaceta1 3) and polyethylene 4). This article is described about the possibility of welding 5)-13) of the dental acrylic resin, the weldability of engineering acrylic resin, cold polymerizing acrylic resin bonding and hot polymerizing acrylic resin bonding. As a results of this series of test and experiments, it is found that welding of dental acrylic resin is possible, whose weldability is about 60%. And, weldability of dental acrylic resin is almost equal to that of engineering acrylic resin.

In this paper we describe an experimental study, in the preceding article, authors reported about the abrasion for composite teeth, in this article are a composite denture which was newly made combining merits of the porcelain and the plastic teeth, a trial production of composite materials of the porcelain and the plastic teeth, and an experimental study of adhesion property of the composite tooth. The following summary can be made from the results of the present experiments. Adhesion of composite denture with filler of porcelain element in principal can be fully expected. In comparison with adhesion strength of P.M.M.A. to P.M.M.A., tensile joint efficiency adhered by P.M.M.A. of heat-cured type was 84-100%, while that of P.M.M.A. of low temperature cured type was 97-98%. Bending joint efficiency using the former adhesive was 87-94%, while that of the latter adhesive was 83-85%.