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91.
BACKGROUND: Neutrophils contribute to the host defense mechanism, but they can cause remote organ injury in peritonitis. The purpose of this study was to examine neutrophil adhesion to the peritoneum and remote organs simultaneously in peritonitis using a fluorescence microscopic method. STUDY DESIGN: Experiment 1: Sprague-Dawley rats (n = 16) were injected intraperitoneally (ip) with saline solution or 10(5), 10(7), or 10(9) Escherichia coli. Five hours after challenge, 1 x 10(6) fluorescein-labeled neutrophils were infused. Two minutes after neutrophil injection, five peritoneal samples (the greater omentum, mesentery, parietal peritoneum, colon, and ileum), both lungs, the liver, and the right kidney were harvested for counting of labeled neutrophils under epifluorescent microscopy. Lung myeloperoxidase (MPO) activity was also determined. Experiment 2: Rats (n = 23) were given 10(9) E. coli ip. Before challenge (0 h) or at 1, 5, or 10 h after challenge, labeled neutrophils were infused. Then, the labeled neutrophil numbers in organs and lung MPO activities were assessed as described for Experiment 1. Hemodynamic and arterial blood gas data were also obtained in another set of rats before and at 1, 5, 8 and 10 h after 10(9) E. coli ip challenge. RESULTS: Experiment 1: The labeled neutrophil numbers in the peritoneum, lungs, and kidney showed significant positive correlations with the injected bacterial numbers. Lung MPO also positively correlated with E. coli number and labeled neutrophil number in the lungs. Experiment 2: Labeled neutrophil numbers in the peritoneum and kidney peaked at 5 h. The pulmonary labeled neutrophil number rose, reaching a plateau at 5 h. No remarkable change was observed in the hepatic labeled neutrophil number. There was a positive correlation between lung MPO activity and pulmonary labeled neutrophil number. Hemodynamic and blood gas data reflected a hyperdynamic state. CONCLUSIONS: Concomitant dose-dependent increases in neutrophil adhesion in the peritoneum, lungs, and kidney were observed in this peritonitis model. Increased neutrophil adhesion was transient in the peritoneum and kidney but persistent in the lungs. Strategies modulating neutrophil adhesion in organs are anticipated to be useful for the treatment of peritonitis. 相似文献
92.
The superconductivity of the tight binding electrons in a magnetic field is studied. We can treat both cases of quasi-one-dimension and quasi-two-dimension in the same manner. We study a various kind of anisotropic superconductivity with line nodes of the energy gap by taking attractive interaction between electrons in nearest sites along each axis. The magnetic field dependence of the transition temperature is calculated for a various pairing symmetry of superconductivity. When a magnetic field is applied in the conducting plane, the transition temperature is shown to increase as the magnetic field increases. In the strong magnetic field the eigenstates approach to those in the absence of hopping between planes, resulting in no orbital frustration. 相似文献
93.
T. Miyazaki K. Yamaoka T. Kaneko J. P. Gong Y. Osada 《Science and Technology of Advanced Materials》2000,1(4):1
A water-swollen hydrogel with a molecularly-ordered structure was prepared by copolymerizing acrylic acid and acrylic monomer containing hydrophobic long alkyl or mesogenic moiety. The gels with a long alkyl side chain formed the crystalline structure and undergo the reversible order–disorder transition with change in temperature or solvent composition which accompanied a dramatic change in Young's modulus. These gels exhibited such chemomechanical behaviors as the shape memory and the rotational motility on the water surface. On the other hand, the gels with the mesogenic side chain formed the liquid crystalline structure with polymorphism in water, and mesophase diagram was established by changing copolymer composition and water content. Mechanism of these structural and chemomechanical behaviors has been explained in terms of order–disorder transition. 相似文献
94.
95.
High-rate deposition of hydrogenated amorphous silicon films using inductively coupled silane plasma
Nobuki Sakikawa Yoshinori Shishida Seiichi Miyazaki Masataka Hirose 《Solar Energy Materials & Solar Cells》2001,66(1-4)
Inductively coupled plasma (ICP) generated at 13.56 MHz has been employed for high-rate deposition of device-quality hydrogenated amorphous silicon (a-Si:H). It has been shown that an increase in the flow rate of a monosilane gas enhances the generation rate of deposition precursors, while the ion flux decreases and becomes saturated. The defect density reaches the minimum at a deposition rate of 2.3 nm/s. It has also been demonstrated that even at deposition rates around 4 nm/s, a-Si:H deposited at 150°C exhibits a subgap defect density lower than 6×1016 cm−3 after 12 h AM1 (100 mW/cm2) light soaking. 相似文献
96.
Hidetoshi Miyazaki Shin-ichi Kikitsu Hisao Suzuki Toshitaka Ota 《Advanced Powder Technology》2011,22(4):544-547
In an effort to improve energy-efficient windows, we experimented with a precursor slurry composite by using needle-like TiO2 particles as the filler in a urethane matrix. Applying dc bias to the slurry failed to array the needle-like particles in the composite and to deposit on the film surface because of electrophoretic movement. However, applying ac bias of ±5 V to the precursor slurry composite for 12 h resulted in the needle-like TiO2 particles being arrayed in the composite in a direction normal to the film surface. This resulted in an improvement in the energy efficiency of the material through an angular dependence of transmittance in the visible–near-infrared range. 相似文献
97.
98.
The content of A-21 desamido insulin (A-21 DI) and B-3 desamido insulin (B-3 DI) in human insulin preparations was measured by new RP-HPLC method using a neutral eluent (pH 6.5). Sometimes the content of B-3 DI in human insulin preparations was about two times larger than that of A-21 DI. In particular, in the case of neutral insulin injection, the content of B-3 DI has increased remarkably as the increase of total desamido content. The content of B-3 DI obtained by the new RP-HPLC method will open the new aspect of the impurity test for insulin preparations. 相似文献
99.
T Harada K Takayama K Kimotsuki K Hidaka H Miyazaki K Kuwano N Hara 《Canadian Metallurgical Quarterly》1996,34(11):1221-1226
A 52-year-old woman was admitted to the hospital because of polyarthralgia and dry coughing. A chest X-ray film showed bilateral diffuse reticulo-nodular shadows. A specimen obtained by transbronchial lung biopsy revealed alveolar septal thickening and infiltration by mononuclear cells. Interstitial pneumonia associated with rheumatoid arthritis was diagnosed. Interstitial pneumonia relapsed soon after the first pulse of corticosteroid therapy. Cyclophosphamide pulse therapy was given in addition to a second pulse of corticosteroid therapy; 700 mg of cyclophosphamide (500 mg/m2) was administered intravenously every month and the dose of steroids was gradually reduced. Cyclophosphamide pulse therapy was repeated three times and the dose of oral corticosteroids was reduced from 60 mg to 35 mg. There was no bone marrow suppression or hemorrhagic cystitis after the cyclophosphamide pulses. Eventually, corticosteroid therapy was stopped with no clinical deterioration. This case suggests that intermittent cyclophosphamide pulse therapy can be effective for treatment of interstitial pneumonia unresponsive to corticosteroids. 相似文献
100.
This paper concerns with a combination method of the boundary element method and the finite element method for elastic-plastic
analyses. The combination method proposed here is based on the substructure method using the conjugate gradient method. This
combination method has the advantage of saving CPU time and memory storage size over the finite element method. The combination
method is applied to a J-integral analysis of a crack in an adhesive joint. The effect of bond thickness on the J-integral
is discussed. 相似文献