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991.
S Yamaguchi Y Ichikawa K Tanaka T Ishikawa H Masui K Koganei K Eguchi H Ike S Ohki H Shimada 《Canadian Metallurgical Quarterly》1996,23(5):529-533
Four prognostics factors were investigated for colorectal cancer metastases. 1) There were statistically more venous invasions using Victoria blue elastic staining in patients with liver or lymph node metastasis than in those without metastasis. 2) The immunohistochemical expression rate of c-erbB-2 in liver metastasis cases was 27%, which was significantly higher than 3% in no metastasis cases. 3) Sialyl Lewis x (SLex) is related with cell adhesion. SLex positive rates in vessel invasion cancer cells were 71.4% with metastasis and 31.0% without metastasis. 4) Matrilysin is one of MMPs and it was significantly increased with Dukes stage by fluorescence intensity. 相似文献
992.
Akio Kawabata Shingo Hirano Masaru Yoshinaka Ken Hirota Osamu Yamaguchi 《Journal of Materials Science》1996,31(18):4945-4949
In the system ZrO2-CeO2, metastable t-ZrO2 solid solutions containing up to 30 mol% CeO2 crystallize at temperatures of 385–430 °C from amorphous materials prepared by the hydrazine method. Crystalline Ce3ZrO8 solid solutions are formed in as-prepared powders between 30–75 mol % CeO2. The variation of the lattice parameters of both solid solutions is determined as a function of CeO2 content. The value of the lattice parameter of pure Ce3ZrO8 (cubic) is a = 0.5342 nm. Detailed characterization of the Ce3ZrO8 powder has been performed. Crystallite size and particle size are strongly dependent on the heating temperature. Specific surface areas do not drop below 40 m2g–1 until the heating temperature is above 1000°C. 相似文献
993.
H Yamada B Fredette K Shitara K Hagihara R Miura B Ranscht WB Stallcup Y Yamaguchi 《Canadian Metallurgical Quarterly》1997,17(20):7784-7795
Brevican is a nervous system-specific chondroitin sulfate proteoglycan that belongs to the aggrecan family and is one of the most abundant chondroitin sulfate proteoglycans in adult brain. To gain insights into the role of brevican in brain development, we investigated its spatiotemporal expression, cell surface binding, and effects on neurite outgrowth, using rat cerebellar cortex as a model system. Immunoreactivity of brevican occurs predominantly in the protoplasmic islet in the internal granular layer after the third postnatal week. Immunoelectron microscopy revealed that brevican is localized in close association with the surface of astrocytes that form neuroglial sheaths of cerebellar glomeruli where incoming mossy fibers interact with dendrites and axons from resident neurons. In situ hybridization showed that brevican is synthesized by these astrocytes themselves. In primary cultures of cerebellar astrocytes, brevican is detected on the surface of these cells. Binding assays with exogenously added brevican revealed that primary astrocytes and several immortalized neural cell lines have cell surface binding sites for brevican core protein. These cell surface brevican binding sites recognize the C-terminal portion of the core protein and are independent of cell surface hyaluronan. These results indicate that brevican is synthesized by astrocytes and retained on their surface by an interaction involving its core protein. Purified brevican inhibits neurite outgrowth from cerebellar granule neurons in vitro, an activity that requires chondroitin sulfate chains. We suggest that brevican presented on the surface of neuroglial sheaths may be controlling the infiltration of axons and dendrites into maturing glomeruli. 相似文献
994.
Yamada H. Yamaguchi M. Kobayashi K. Matsuura Y. Takano H. 《IEEE engineering in medicine and biology magazine》1995,14(1):84-90
The authors first explain the structure and features of the linear pulse motor (LPM) developed to drive the total artificial heart (TAH). Then they describe the linear motor-driven TAH using the LPM as the driving source, which the authors call linear TAH, and the configuration of a human model in which the linear LAH is installed. Next, the authors describe the results of evaluating the pump performance of the linear TAH in vitro by using a mechanical mock circulatory testing system. Finally, the authors report information resulting from the evaluation of the linear TAH in vivo in an acute animal test using a sheep 相似文献
995.
Four popular West African local cultivars of cowpea (Vigna unguiculata), with distinctly different seed coat colors, were evaluated for their relative amylograph pasting characteristics, condensed tannin content, in vitro protein digestibility and Tetrahymena protein efficiency ratio (t-PER). The effects of roasting and dehulling on these properties were also determined. There were wide variations in the hot paste viscosity characteristics of the different cultivars studied. The raw cowpea flour samples exhibited maximum paste viscosities ranging between 260 Brabender Units (BU) for the Mottled cultivar and 460 BU for the cream-colored Blackeye cultivar. Cowpea cultivars with the greatest peak viscosities showed low stabilities to extended cooking. Roasting depressed paste viscosity properties of all the cowpea cultivars studied. Tannin concentrations were 0.3-6.9 and 7.2-116 mg CE/g flour from whole cowpea seeds and seed coats respectively, increasing with intensity of seed color. Although dehulling removed 98% of the tannin content of raw cowpeas, improvement in protein quality as a result of dehulling was observed for only the highly-pigmented Maroon-red variety. Roasting significantly improved digestibility and more than doubled the t-PER of all cowpea cultivars studied. Roasted cowpeas possess adequate nutritional and functional qualities as protein supplements in cereal-based weaning foods. However, it appears that dehulling is necessary to enhance the nutritional quality of the highly pigmented cultivars of cowpea. 相似文献
996.
Tooru Tanaka Nobutaka Tanahashi Toshiyuki Yamaguchi Akira Yoshida 《Solar Energy Materials & Solar Cells》1998,50(1-4):13-18
Cu(InxGa1−x)2Se3.5 thin films were fabricated by rf sputtering from CuInxGa1−xSe2 and Na mixture target by controlling the mixture ratio. X-ray diffraction analyses show that the structure of Cu(InxGa1−x)2Se3.5, thin films is different from chalcopyrite structure: especially, CuIn2Se3.5 thin films have a defect chalcopyrite structure. The lattice parameters for Cu(InxGa1−x)2Se3.5 thin film are slightly smaller than those for CuInxGa1−xSe2 thin film and linearly decreased with increasing Ga content. The optical absorption coefficients for Cu(InxGa1−x)2Se3.5, thin films exceed 2 × 104 cm−1 in energy region above the fundamental band edge. The band gap for Cu(InxGa1−x)2Se3.5 thin films is larger than that for CuIn.Ga1−x2Se2 with the same Ga content and increased with increasing Ga content. 相似文献
997.
K Katsura S Nomura T Ohtani N Matsumoto T Shimizu K Yamaguchi Y Kishimoto H Kitajima S Fukuhara 《Canadian Metallurgical Quarterly》1998,124(11):633-640
PURPOSE: Recently high-dose chemotherapy with peripheral blood stem cell transplantation (PBSCT) has become an important treatment for hematological and solid tumors. METHODS: Immunological parameters were examined before and after PBSCT in 9 patients with lung cancer and 13 patients with malignant lymphoma. Findings were compared with those for bone marrow transplantation (BMT). Peripheral blood cells were analyzed for phenotype and the levels of cytokines and soluble factors were measured. RESULTS: After PBSCT, activated T cells (CD3+HLA-DR+ cells, CD8+HLA-DR+ cells) and suppressor/cytotoxic T cells (CD8+CD11b- cells) were significantly higher in the patients with lung cancer than in those with malignant lymphoma. Serum levels of interleukin-4 and soluble interleukin-2 receptor were also significantly higher in the patients with lung cancer than in those with lymphoma. On the other hand, the serum levels of interferon gamma, tumor necrosis factor alpha, interleukin-6, soluble human leukocyte antigen class 1, and soluble thrombomodulin were significantly increased after bone marrow transplantation. The transfused peripheral stem cells of lung cancer and lymphoma patients had a similar number of granulocyte/macrophage-colony-forming units, but lung cancer patients had significantly more CD34-positive cells. CONCLUSION: By reinfusing large numbers of autologous immune cells, PBSCT may accelerate immune reconstitution, with T cells being likely to have a marked therapeutic potential. The changes after PBSCT were greater in patients with lung cancer than in lymphoma patients. These blood cells are potent mediators of anticancer activity and could play an important role in the elimination of autologous malignant cells. 相似文献
998.
999.
1000.
Kimuro B. Kusayanagi T. Yamaguchi F. Ohtsubo K. Morishita M. 《Energy Conversion, IEEE Transaction on》1994,9(4):732-735
CO2 disposal in the deep ocean is expected to be an effective option for mitigating the increase in CO2 on the earth. The authors have investigated the behaviour of liquid CO2 using test facilities which can simulate the pressure and temperature of the deep ocean. Phase equilibrium data of the CO2 -seawater system and the conditions of CO2 clathrate formation were confirmed. In addition, the authors measured the pH value of seawater saturated with CO2 at high pressure. The data presented in this paper are considered indispensable for evaluating the possibility of CO2 disposal in the deep ocean 相似文献