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621.
Hata S Shiraishi K Itakura M Kuwano N Nakano T Umakoshi Y 《Journal of electron microscopy》2004,53(5):537-540
Metastable long-period superstructures in an L10-TiAl single crystal with a composition gradient were observed successfully by transmission electron microscopy with a focused ion beam (FIB) microsampling technique. The composition gradient from 54.7 to 75 at.% Al with approximately 6 microm width was detected by electron probe microanalysis and foil specimens containing the composition-gradient area were fabricated by the FIB microsampling method. The foil specimens clearly exhibit sequential changes in long-period superstructure depending on the Al concentration. 相似文献
622.
Shimizu K Hayashi S Doukyu N Kobayashi T Honda H 《Journal of Bioscience and Bioengineering》2005,99(1):72-74
A time-course gene-expression profile was generated for Escherichia coli TK31 when it was exposed to an organic solvent mixture, and classified by fuzzy adaptive resonance theory (Fuzzy ART). It was found that the purR regulon plays an important role in the organic solvent tolerance (OST) of E. coli. 相似文献
623.
To design optimal electrical machines, it is necessary to develop an optimal design method for determining the shapes, sizes, positions of the cores, permanent magnets and windings which produce such specified values as flux distributions and torques. In this paper, a design method for determining the optimal sizes of cores taking into account the nonlinearity of the core has been developed by using the nonlinear programming method and the magnetization integral equation method. The pole shape of an electromagnet which produces the uniform flux distribution is determined by using the design method for determining the optimal sizes of cores. The effectiveness of the method is shown by designing the pole piece of the permanent magnet-type MRI device. 相似文献
624.
Noriyuki Oba Hisao Sugimura Yasuhiko Umehara Masayuki Yoshida Talzo Kimura Takaji Yamaguchi 《Lipids》1992,27(9):701-705
A water-in-oil-in-water (W/O/W) emulsion composed of oleic acid was used as a carrier of carboxyfluorescein (CF)via the enteral route, as a model for future drug transport. The absorption of CF in the small intestine of rats given the emulsion
(W/O/W group) was compared with the absorption in a group administered CF alone (CF group), and a surface-active agent in
CF solution (MM group). Higher amounts of CF were absorbed in the W/O/W and MM groups than in the CF group. At 120 min, the
amount of CF remaining in the intestinal tract was smaller in the MM group than in the W/O/W group. In the early period, CF
excretion into bile was higher in the MM group than in the W/O/W group was higher than in the MM group (non-specific). The
blood CF level was significantly higher at 240 and 360 min in the W/O/W group than in the other two groups. The highest concentration
in lymph was found in the W/O/W group. The W/O/W emulsion was considered superior to the micelles because it maintained a
higher blood level of CF over long periods and transferred it to the lymph. This suggests that the W/O/W emulsion is applicable
as a drug carriervia the enteral route. 相似文献
625.
Nilvadipine solid dispersions were prepared by the solvent method using water-insoluble polymers, including low-substituted hydroxypropylcellulose, croscarmellose sodium, carmellose calcium, carmellose, and crospovidone. Differential scanning calorimetry and powder x-ray diffraction analysis showed that nilvadipine was present in an amorphous state in the solid dispersion obtained using crospovidone as a carrier. The degree of crystallinity of nilvadipine was dependent on the ratio of nilvadipine to crospovidone, and nilvadipine was present in an amorphous state when the ratio of nilvadipine to crospovidone was below one-half. Fourier transform infrared studies suggested the presence of hydrogen bonding between nilvadipine and crospovidone in the solid dispersion. Dissolution studies indicated that the maximum percentage of dissolution and dissolution rate constants were markedly increased in nilvadipine with crospovidone solid dispersion, compared with those of pure nilvadipine and physical mixtures. The dissolution rate of nilvadipine solid dispersion with crospovidone could be calculated by the Higuchi square root time equation. 相似文献
626.
N Kawahata Y Kamada A Ohtsuka Y Kamashita Y Nishi T Hamano E Nagaoka 《Canadian Metallurgical Quarterly》1998,25(12):914-920
We have developed a visual analysis method to examine the spatial relationship between the edentulous ridges and the bucco-lingual position of the artificial posterior teeth in complete denture fabrication. In this system, a non-contact type shape measurement system is used. We applied this system to the plaster models and the wax dentures of an edentulous patient. Using the measurement data on the upper and lower plaster models, we reconstructed their shape three-dimensionally and determined the points regarded as the ridge crests and the inter-alveolar crest lines in the frontal sections. To generate the upper and lower ridge crest lines which consisted of the points of the ridge crests, interpolation by B-spline curves was applied. Furthermore, the loft surfaces that we regarded as the consecutive inter-alveolar crest lines, were generated between the upper and lower ridge crest lines. The surface models of the plaster models and artificial teeth were displayed on the cathode-ray tube display unit, and the ridge crest lines and the consecutive inter-alveolar crest lines were superimposed on the surface models. This method could be utilized to visualize and examine the bucco-lingual position of the artificial posterior teeth in reference to the inter-alveolar crest lines. 相似文献
627.
I Nagaoka Y Tsutsumi-Ishii S Yomogida T Yamashita 《Canadian Metallurgical Quarterly》1997,272(36):22742-22750
Neutrophils contain various antibacterial polypeptides and proteins in the granules that contribute to the killing of microorganisms. Recently, we have purified a cationic antibacterial polypeptide of 11 kDa (CAP11) from guinea pig neutrophil granules. CAP11 is a homodimer of G1LRKKFRKTRKRIQKLGRKIGKTGRKVWKAWREYGQIPYPCRI43 joined with one disulfide bond. In this study, to understand the regulation of CAP11 expression, we isolated and analyzed cDNA encoding CAP11. Furthermore, we investigated the expression of CAP11 mRNA during neutrophil maturation and localization of CAP11 among neutrophil granule subsets. Sequence analysis of CAP11 cDNA isolated from guinea pig bone marrow cells using rapid amplification of cDNA ends technique indicated that CAP11 is synthesized as a precursor comprising 178 amino acid residues, which is composed of a signal peptide (N-terminal 29 residues), a propeptide (106 residues), and a C-terminal mature peptide (43 residues). Interestingly, the predicted CAP11 precursor displayed the characteristic features of cathelicidins, a novel protein family of antibacterial polypeptides with a conserved cathelin-like pro-region and a variable C-terminal antibacterial domain. Northern blot and Western blot analyses using neutrophils, macrophages, eosinophils, mononuclear cells, and bone marrow cells revealed that only neutrophils and bone marrow cells expressed CAP11 mRNA and contained CAP11, suggesting that expression of CAP11 is neutrophil lineage-specific. Furthermore, Northern blot analysis using bone marrow cells separated according to their maturation stages showed that CAP11 mRNA was predominantly expressed in the cells at later stages of neutrophil maturation. Consistent with this, in situ hybridization using CAP11-specific cRNA probe demonstrated that CAP11 mRNA was primarily expressed at metamyelocyte stage. In addition, extracellular release assay revealed that CAP11 was readily released from neutrophils accompanied with gelatinase by low concentrations of N-formyl-Met-Leu-Phe without release of specific and azurophil granule components, and CAP11 was found to be exclusively present in the fraction containing gelatinase granules, prepared by Percoll density gradient centrifugation. Together these observations indicate that CAP11 is a member of cathelicidin family and its mRNA is preferentially expressed at the later stage of neutrophil maturation (i.e. metamyelocyte stage). Furthermore, CAP11 may be stored in the granule subset, possibly the gelatinase granule. 相似文献
628.
Izumi Tsuda Kazue Setoguchi Noriyuki Tatsumi 《Journal of Automated Methods and Management in Chemistry》1990,12(3):104-107
Two data interpretation programs incorporated into two different automated blood cell counters were evaluated. The programs analysed size distribution histograms for screening for abnormal specimens. The messages given by the programs were ‘normal’, ‘abnormal’ and ‘suspect’. ‘Abnormal’ messages meant abnormalities in the values of the measured parameters. ‘Suspect’ messages were given when the histograms showed either a possibility of the existence of abnormal blood cells, or an abnormal level of such cells; re-examination by a manual method was necessary for such specimens. For reference, the manual differential was done. The false-negative rate for each kind of message was less than 10% and efficiency was about 90%. These programs were helpful in avoiding unnecessary manual observations in reducing the workload in a routine clinical laboratory. 相似文献
629.
H. Mori S. Kitamura T. Nagaoka A. Takekawa N. Yamaguchi 《Mathematics and computers in simulation》1982,24(6):564-568
The Auto-Regression method was applied to the modelling of leukemic states. The number of two kinds of normal cells and of a kind of abnormal cells in the peripheral blood were taken as output variable. The model obtained explained the trend of the normal cells in the prediction, while it could not satisfactorily follow the time course on the knowledge on the drug effect to the abnormal cells was constructed. The conbination of these two models seems to be feasible for describing the dynamics of leukemic states. 相似文献
630.
Poly(ethylene glycol)s (PEG) were crosslinked with divalent metal salts of mono(hydroxyethyl) phthalate, anhydride, and bisepoxide to give metal-containing cured rubbers. As the anhydride, hexahydrophthalic anhydride was used, and bisphenol A diglycidyl ether was the bisepoxide used. As for the physical properties of the cured rubbers obtained, the rubbers containing Mg showed much better physical properties than those containing Ca. In addition, the rubbers with high hard block contents and high overall crosslinking densities exhibited high tensile strength and Shore A hardness, and so did the rubbers having a high degree of crystallinity of the PEG soft block. The occurrence of crystallization became easy as the soft block length became longer and the soft block content became higher, or as the crosslinking density of the hard block became lower. The PEG-based rubbers showed much higher water absorption than the previously reported poly(propylene glycol)-based rubbers, due to the much higher hydrophilicity of the PEG block. Resistance to chemical attack and stress–relaxation are also discussed. 相似文献