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991.
The standard enzymatic assay for quantification of D-sorbitol in plasma was adapted to the automatic analyzer Cobas Mira S. In the assay, NAD (reagent) in the presence of sorbitoldehydrogenase (SDH; start reagent) converts D-sorbitol to fructose with formation of NADH, which was detected automatically as the difference between the first and last readings at 340 nm. The sample blank values for each specimen were subtracted to exclude both endogenous D-sorbitol and sugars, which also react as substrates for SDH. The method is simple, rapid (40 samples/h), precise down to endogenous concentrations (coefficient of variation < 5%; limit of determination: 0.38 mg/L) and linear up to 100 mg/L. Samples with higher D-sorbitol concentrations were estimated after dilution. The method was used to measure disposition curves of sorbitol in volunteers after a single intravenous dose of 0.8 g sorbitol. 相似文献
992.
T Ayabe H Takenaka O Takenaka A Takenaka H Nagahama H Maruyama A Yamamoto M Nagata Y Koga M Sumida M Hamada 《Canadian Metallurgical Quarterly》1996,38(2):373-381
The pMEX8-hAK1 vector was devised from the pAK plasmid (Kim J. H. et al., 1989, Protein Engineering 5, 379-386), which could directly express human adenylate kinase proteins without recombination and its single strand DNA could be withdrawn with helper phage for random site-directed mutagenesis. The conserved key residues at Lys21, Lys27, and Thr39 were engineered to obtain mutants for kinetic analysis. Three mutants were obtained as K21P, K27R, and T39S, their specific activities were strikingly reduced compared to those of wild type adenylate kinase. This pMEX8-hAK1 will be a powerful tool for site-directed mutagenesis to detect the substrate-enzyme interaction for human adenylate kinase including various other enzymes. 相似文献
993.
994.
Residual electrical resistivity due to short-range order has been calculated for Cu100-xAlx (x=9.13,13.56, 14.5 and 14.76 in at pct) alloys using pseudopotential approach, and the results have been discussed in the light of experimental studies of the local-order structure of these alloys. In case of Cu85.5Al14.5, change in the total residual electrical resistivity due to neutron-irradiation effects has been estimated by including contributions from the short-range order and static atomic displacement correction. Our results show a decrease in the residual resistivity in the irradiated Cu-Al solid solution as compared to the unirradiated sample. This is in accordance with the experimental results 相似文献
995.
A new gram-positive, nonmotile coccus is described. Strains IFO 12422T (T = type strain) and IFO 15385 in the Institute for Fermentation, Osaka, culture collection, which were isolated from soil and water, respectively, have the following chemotaxonomic characteristics: menaquinone MK-9(H4); G + C content of DNA of 67 mol%; and LL-diaminopimelic acid, alanine, glycine, and glutamic acid in a molar ratio of ca. 1:2:1:1 (type A3 gamma). Mycolic acids are not present. The taxonomic characteristics of these organisms are different from those of previously described gram-positive, high-G + C-content cocci. The partial 16S rRNA sequence indicated that IFO 12422T represents a distinct line of descent among gram-positive bacteria with a high G + C content. The name Luteococcus japonicus gen. nov., sp. nov. is proposed. The type strain is strain IFO 12422. 相似文献
996.
997.
Translated from Izmeritel'naya Tekhnika, No. 2, pp. 45–46, February, 1992. 相似文献
998.
A. Mandrino R. Eloy B. Moyen J. L. Lerat D. Treheux 《Journal of materials science. Materials in medicine》1992,3(6):457-463
Base alumina ceramics with dispersoids (BAC) are a new class of ceramics with improved mechanical properties as compared to pure alumina. They are obtained by dispersion of powder within an alumina matrix. Of the three new ceramics studied here, A20Z possesses the best mechanical properties as well as tribological properties superior to those of pure alumina whether it is used in ceramic-ceramic or ceramic-polyethylene combination.Mechanical behaviour and tissue response afterin vivo implantation were studied. Small four-point flexion bars obtained by pressureless sintering were implanted subcutaneously in the rat. The mechanical properties were unmodified even after one year from implantation.The tissue response was studied up to one year on cylinders implanted in the paravertebral muscles of Wistar rats, and was evaluated by qualitative examination of the encapsulating membrane and measurement of its thickness in relation to pure alumina. The tissue responses were comparable for both alumina and the three tested ceramics. 相似文献
999.
A. Inoue B. G. Kim K. Nosaki T. Yamaguchi T. Masumoto 《Journal of Materials Science Letters》1992,11(12):865-867
On leave from: Honda Research and Development Co., Ltd, Wako 351-01, Japan. 相似文献
1000.
Gilbert A. Hartley Ahmed Abdel-Akher Peilei Chen 《International journal for numerical methods in engineering》1992,35(9):1771-1785
Procedures are described for modelling a structural system consisting of thin Kirchhoff plates with internal patch areas capable of displacing as rigid flat surfaces. The physical prototype for these patches could be interconnection points for one-dimensional frame type elements of various shapes and layout, rigidly connected at these finite size 'joints' in the plate. The numerical procedure for modelling the thin plate is the Direct Boundary Element Method (DBEM) and a simple overview of this procedure is provided. Potential trouble spots, of which the user should be aware, are described. The paper will be of interest to structural engineers for analysis of frames having both plate and simple frame elements, for example, building frames; and also to researchers seeking the greater detail that this refined procedure can provide. As a practical tool, the methods described are computationally competitive with existing procedures, including the more rugged approaches used by building structural engineers for dynamic and torsional analysis. 相似文献