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ヒ素化合物のラット赤血球への移行
Get PDFapplication/pdfIn measuring the osmotic fragility of rat erythrocytes by centrifugation using coil planet centrifuge, it was found that arsenic trioxide given orally to rats caused a significant increase in the osmotic fragility. However, in vitro tests on the erythrocytes in which one ml of blood was incubated with arsenic trioxide equivalent to 2～500μg of arsenic at 37℃ for 1 hr, no significant changes were observed. Monomethylarsonic acid and dimethylarsinic acid, known as metabolites of inorganic arsenic, induced no significant changes in the osmotic fragility in vitro tests on erytherocytes. The arsenic concentration in erythrocytes was measured in the tests in vitro and in vivo using flameless atomic absorption spectrometry. When arsenic was given orally to rats, more than 90% of arsenic in whole blood was found in erythrocytes. However, in vitro tests, only 30.4～47.5% was detected on erythrocytes even after 6 hrs incubation. These results obtained in relation to arsenic concentration may explain the effect of the arsenic on the osmotic fragility of rat erythrocytes.journal articl
口腔内の色彩に関する研究 第6報 Micro-Color-Computer受光器改良と陶歯の色(1)VITA-LUMIN
Get PDFapplication/pdfTo know the accurate color of the natural and artificial teeth, the Micro-Color-Computer was devised. The reflecting, retracting, and transmitting of incident rays caused by the surface gloss and the microstructure of the natural and artificial teeth have prevented accurate measurement of color shade. It was concluded that the structure of the radiation detector might be improved in order to settle the problem. Thus, a new radiation detector was devised and this experiment was carried out. The structure of the radiation detector: A 2mm wide detector surrounds around the light source, which is 3mm in diameter, and the whole body is designed mobile. The source of radiation can also be moved close to the teeth so that it can perceive the diffused reflection of the surface the transmitted incident rays. Therefore, this radiation detector in basic experiment of Opal-glass standard plate was used and then the shade-guide of VITA-LUMIN was surveyed, to find out the best position that suits the measuring conditions of the radiation detector. Result: No difference in color tendency was seen against the transposition of the radiation detector. But as the radiation detector gets far from the material, an entire decrease in co-ordinates of color was admitted. Based upon this fact, it may be concluded that the adequate distance between the radiation source and the radiation detector is within 1～3mm from the materialjournal articl
口腔内の色彩に関する研究 第8報 歯牙におけるMicro-Color-Computerと肉眼的測定値との比較
Get PDFapplication/pdfIn the sixth and the seventh report, shade-guide was measured by using an improved radiation detector. As the result, it was able to conclude that the positional relation between the optical receptor and the light source was within 1～3mm in length. Thus, on this report, it was compared that the correlation of the shade-guide of a testee which had been selected in the Integral Calculus Globe, the measured value, and the value selected by the naked eye. First, the shade-guide on natural teeth of 5 testees was selected with unaided eye in the Integral Calculus Globe. Also shade-guide of the same natural teeth was measured using the improved radiation detector and compared both results. Result: In the range of 1～3mm, the position of the radiation detector which gave the minimum value of Hunter color distinction (△E) was 2mm. Thus, in this experiment, it was concluded that the best radiation detector for measurement of the teeth would be a detector which is placed 2mm far from the tip of the source of radiation.journal articl
特異な嚢胞様構造を呈したAmeloblastomaの1症例
Get PDFapplication/pdfAmeloblastoma formed a unicyst-like structure lined with stratified squamous epithelium was occurred in a 41-year-old man. The present case had apparent transformation between the lining epithelium and the columnar cells of ameloblastoma proliferated inside the "cyst". The fabricating mechanism of this structure was examined microscopically and compared with another cyst forming lesions such as follicular dental cyst, radicular cyst and traumatic bone cyst by referring to reported papers extensively. After this consideration, it was concluded that the lining epithelium of this structure would come from metaplasia of the columnar cells which covered the follicles of the ameloblast oma. And this structure would be a number of follicles of this lesion from the biginning, and since then, they would become a "cyst" by mutual expansion and confusion by means of some unknown factors.journal articl
Purification and Properties of Hyaluronidase (EC 4. 2. 2. 1) from an Oral Strain of Propionibacterium acnes
Get PDFapplication/pdfFrom a culture supernatant of P. acnes isolated from a lesion of periodontal disease, hyaluronidase was purified to homogeneity by the sequential procedures including ammonium sulfate precipitation, carboxy methy-cellulose column chromatography, and Sephadex G-100 gel filtration. Specific activity increased 1,027 fold and the recovery of the enzymatic activity was 12.4%. Molecular weight was determined to be 67,000 and isoelectric point was 7.2. Optimal pH for the activity was found at 5.5. The enzyme was inactivated by heating at 60℃ for 10 min. The purified hyaluronidase degraded hyaluronic acid, chondroitin, chondroitin sulfate A and chondroitin sulfate C. From the degradation products of these substrates, unsaturated disaccharides were detected by paper chromatography. When the rate of reaction of this enzyme against hyaluronic acid is supposed to be 100%, the corresponding values against chondroitin, chondroitin sulfate A, and C were 47%, 8%, and 8%, respectively. No degradation by this enzyme of heparin and heparan sulfate was demonstrated.journal articl
