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991.
F Matsuda K Ishii P Bourvagnet K Kuma H Hayashida T Miyata T Honjo 《Canadian Metallurgical Quarterly》1998,188(11):2151-2162
The complete nucleotide sequence of the 957-kb DNA of the human immunoglobulin heavy chain variable (VH) region locus was determined and 43 novel VH segments were identified. The region contains 123 VH segments classifiable into seven different families, of which 79 are pseudogenes. Of the 44 VH segments with an open reading frame, 39 are expressed as heavy chain proteins and 1 as mRNA, while the remaining 4 are not found in immunoglobulin cDNAs. Combinatorial diversity of VH region was calculated to be approximately 6,000. Conservation of the promoter and recombination signal sequences was observed to be higher in functional VH segments than in pseudogenes. Phylogenetic analysis of 114 VH segments clearly showed clustering of the VH segments of each family. However, an independent branch in the tree contained a single VH, V4-44.1P, sharing similar levels of homology to human VH families and to those of other vertebrates. Comparison between different copies of homologous units that appear repeatedly across the locus clearly demonstrates that dynamic DNA reorganization of the locus took place at least eight times between 133 and 10 million years ago. One nonimmunoglobulin gene of unknown function was identified in the intergenic region. 相似文献
992.
N Yoshikawa H Ito Y Takekoshi M Honda M Awazu K Iijima H Nakamura Y Seino N Takeda S Hattori I Matsuda 《Canadian Metallurgical Quarterly》1998,40(8):587-590
A hospital-based matched case-control study was conducted in order to identify risk factors for the development of bloodstream infections in adult hospitalized patients. Between January 1993 and December 1994, 264 episodes of bloodstream infection were evaluated. Significant variables identified by univariate analysis were included in a multivariate model that showed that central venous catheter [odds ratio (OR), 6.71], poor performance status (OR, 3.40), weight loss (OR, 2.47), hematologic diseases (OR, 2.24), and previous antimicrobial therapy (OR, 2.12) independently influenced the outcome. The knowledge of modifiable risk factors is useful in the development of strategies that may contribute to the prevention of bloodstream infections. 相似文献
993.
Y Hayashi Y Sawa M Nishimura JC Chang A Amemiya K Kagisaki S Taketani T Yamaguchi N Hirata S Ohtake H Matsuda 《Canadian Metallurgical Quarterly》1998,44(5):M456-M461
Heparin coated bypass circuits have been reported to improve the biocompatibility of extracorporeal circulation, although it is still insufficient and improvable. Nitric oxide (NO) is known to inhibit platelet activation and inflammatory reactions. In this study, the authors evaluated exogenous NO infusion in enhancing the effect of a heparin coated bypass circuit on the biocompatibility of an extracorporeal circuit, especially in view of the attenuation of the inflammatory response. A miniature closed bypass circuit, including an oxygenator (BioActive surface; Carmeda, Stockholm, Sweden) was primed with fresh human heparinized blood and perfused with a centrifugal pump. Either pure N2 gas (control group: n = 7) or NO gas (NO group [100 ppm in N2]: n = 7) was infused to the oxygenator. NO metabolites (nitrite and nitrate), platelet count, thrombin-antithrombin III complex (TAT), alpha2-plasmin-plasminogen inhibitor complex (PIC), beta-thromboglobulin (beta-TG), platelet factor 4 (PF4), serotonin, complement 3 activation products (C3a), granulocyte elastase, and bradykinin were measured at 0, 30, 60, 120, and 180 min after starting perfusion. At every sampling point, platelet counts were significantly higher, and TAT, beta-TG, and bradykinin were lower in the NO group than in the control group. PF4, C3a, and granulocyte elastase were significantly lower in the NO group at 60, 120, and 180 min. These results suggest that NO gas infusion to the oxygenator enhances the biocompatibility of heparin coated extracorporeal circuits. 相似文献
994.
H. Miyahara M. Takai T. Nishimoto M. Kondo A. Matsuda 《Solar Energy Materials & Solar Cells》2002,74(1-4)
Electrode distance between cathode and anode is one of the important parameters for fabricating hydrogenated amorphous silicon (a-Si:H) using plasma-enhanced chemical-vapor-deposition system with parallel plate electrodes. In this work, we have investigated the relationship between electrode distance and stability of a resulting a-Si:H. The stability is improved with decreasing electrode distance. At shorter electrode distance, formation of higher silane-related-reactive species is suppressed by heating effect of gas molecules near the cathode due to a proximity to the heated anode. Using cathode heating method, the stability of a-Si:H is improved even at long electrode distances. 相似文献
995.
Abstract. We propose a test for separability of the correlation structure of a multivariate time series. We construct test statistics based on a spectral density matrix estimated in a nonparametric way and derive their asymptotic properties. We use simulation to check the performance in finite samples. 相似文献
996.
T. Matsuda 《Journal of Materials Science》1989,24(7):2353-2357
Chemically vapour-deposited boron nitride (CVD-BN) plates prepared by use of the BCl3-NH3-H2 gas system were investigated as to their stability to moisture. Infrared (IR) spectroscopic measurement, chemical analysis and thermal gravimetric analysis were used in this study. The synthesis conditions of CVD-BN plates have a large influence on their stability to moisture. The stability of CVD-BN plates prepared under a total gas pressure (P
tot) of 10 to 60 torr degraded as the deposition temperature (T
dep) was lowered. The CVD-BN plates with transparent and isotropic properties, which were prepared at below 1400° C and above 10 torr, showed poor stability to moisture, The CVD-BN plates synthesized under 5 torr had high moisture-resistance, even at aT
dep as low as 1400° C. An IR absorption spectral study revealed that the unstable species existing in CVD-BN plans had changed to ammonium borate hydrates by reacting with moisture in the atmosphere. The stability to moisture for CVD-BN plates degraded as the deposition roe was raked, especially for the CVD-BN plates prepared at 1400° C. 相似文献
997.
H Matsuda Y Ose H Nagase T Sato H Kito K Sumida 《The Science of the total environment》1991,103(2-3):129-140
Eight components of humic substances were ozonated. Mutagenic activity was found with TA100 with and without S9 mix for all ozonated components. Ozonated products of p-hydroxybenzaldehyde were separated into five fractions by silica gel chromatography and each fraction subjected to mutagenicity assay. Mutagenic activity was found in the chloroform and chloroform-acetone (1:1) fractions. The compounds in these fractions were identified, and aldehydes such as formaldehyde, acetaldehyde, glyoxal, glyoxylic acid and methyl glyoxal were found to be mutagenic. Mutagenic compounds are present in the polar fraction. 相似文献
998.
M Mouri Y Nambu M Matsui Y Kobayashi N Kishimoto T Noguchi M Matsuda S Sakurai N Ohya 《Canadian Metallurgical Quarterly》1993,31(5):629-635
A 60-year-old woman was admitted to our hospital with a two month history of dry cough and dyspnea on exertion. A chest roentgenogram revealed diffuse interstitial shadows with a reduction of lower lung volume. Laboratory examinations revealed an increase in CPK and aldolase. There was decreased proximal muscle power, and the findings of a biopsy of the right deltoid were compatible with polymyositis. Myositic symptoms were stable, but the respiratory symptoms worsened, and an open lung biopsy was performed for diagnosis and to determine the best treatment. The histological findings of biopsy materials demonstrated active interstitial pneumonia complicated by cellular interstitial pneumonia, bronchiolitis obliterans organizing pneumonia, usual interstitial pneumonia and lymphoid hyperplasia. The patient responded well to adrenocorticosteroid and immunosuppressive therapy, and is now attending as an out patient. It is well known that PM-DM can be associated with interstitial pneumonia, and this complication is an important prognostic factor clinically. The pathological patterns of interstitial pneumonia in PM-DM may be divided into usual interstitial pneumonia and bronchiolitis obliterans organizing pneumonia. Furthermore, it is well documented that these patterns are concurrent with the response to adrenocorticosteroid and prognostic factors. However, our case of PM-DM, in which various patterns such as rheumatoid arthritis (RA) were pathologically revealed, cannot be considered as having uniform pathological pattern. We consider that pulmonary pathological patterns of PM-DM are very varied, as with RA. It is a very important to evaluate the nature of these patterns and the subsequent clinical course in PM-DM with interstitial pneumonia. 相似文献
999.
1000.