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41.
T Masubuchi S Koyama E Sato A Takamizawa K Kubo M Sekiguchi S Nagai T Izumi 《Canadian Metallurgical Quarterly》1998,153(6):1903-1912
Inflammatory cells accumulate within the lungs of cigarette smokers. Current concepts suggest that these cells can induce protease-antiprotease and/or oxidant-antioxidant imbalance(s), which may damage the normal lung alveolar and interstitial structures. Because type II pneumocytes line the alveolar space, and because the inflammatory cells migrate and reside at the alveolus, we postulated that the type II pneumocytes might release chemotactic activity for neutrophils and monocytes in response to smoke extract. To test this hypothesis, A549 cells were cultured and the supernatant fluids were evaluated for the neutrophil and monocyte chemotactic activity (NCA and MCA) by a blind-well chamber technique. A549 cells released NCA and MCA in response to smoke extract in a dose- and time-dependent manner (P < 0.05). Checkerboard analysis showed that the activity was chemotactic. Partial characterization of NCA and MCA revealed that the activity was partly heat labile, trypsin sensitive, and ethyl acetate extractable. Lipoxygenase inhibitors and cycloheximide inhibited the release of NCA and MCA. Molecular sieve column chromatography showed multiple peaks for both NCA and MCA. NCA was inhibited by anti-human-interleukin (IL)-8 antibody, granulocyte colony-stimulating factor (G-CSF) antibody, or leukotriene (LT)B4 receptor antagonist. Monocyte chemoattractant protein (MCP)-1 antibody or LTB4 receptor antagonist inhibited MCA. Immunoreactive IL-8, G-CSF, MCP-1, and LTB4 significantly increased in the supernatant fluids in response to smoke extract. These data suggest that the type II pneumocytes may release NCA and MCA and modulate the inflammatory cell recruitment into the lung. 相似文献
42.
H Matsuno E Sugiyama A Muraguchi T Nezuka T Kubo K Matsuura H Tsuji 《Canadian Metallurgical Quarterly》1998,20(6):295-304
SA96 (generic name, bucillamine) is a disease-modifying anti-rheumatoid arthritis (RA) drug with immunological effects. This compounds has two sulfhydryl groups in its molecule, and the differences and similarities between this drug and D-penicillamine, which is also a sulfhydryl group-containing anti-rheumatic drug, have frequently been discussed. To clarify the pharmacological differences between these two drugs, we examined the concentrations of the compounds and its metabolites in serum and synovial fluid, paying special attention to the metabolites of SA96 produced in vivo. SA96 was metabolized in a very short time to SA981 which is a disulfide compound formed by intramolecular binding of two sulfhydryl groups, and transferred to synovial fluid. In addition SA981 had significant suppressive effects on IL-6 and IL-8 production by synovial cells in vitro. These results demonstrate that SA96, which has two sulfhydryl groups, exhibits anti-rheumatic effects via a pharmacological action clearly different from that of D-penicillamine. 相似文献
43.
44.
E Sato H Yamamoto T Honda S Koyama K Kubo M Sediguchi 《Canadian Metallurgical Quarterly》1996,9(2):386-388
We report the case of a 34 year old woman with acute respiratory distress syndrome (ARDS) and disseminated intravascular coagulation (DIC) due to methicillin-resistant Staphylococcus aureus (MRSA) sepsis with hyperimmunoglobulin E syndrome (HIES). Although chemotactic activity of neutrophils was impaired in this patient, neutrophils accumulated in the lungs as assessed by bronchoalveolar lavage fluid (BALF) counts. In addition to antibiotics and oxygen therapy, the administration of recombinant human granulocyte colony-stimulating factor (rhG-CSF) resulted in a remarkable recovery. 相似文献
45.
46.
A laser interferometer gravitational wave detector requires an ultra high vacuum in the tubes in which the laser beams pass. To avoid noise due to scattered light from the surface of tubes, the surface should be treated with “black” coating without increasing the outgassing rate. We found that diamond-like Carbon (DLC) coatings are suitable for this aim. An outgassing rate of at was achieved for DLC coatings on SUS304 without baking. This rate was better than the surface of SUS316 with baking. The reflectivity of the DLC surface was 5% at minimum for a laser beam of Nd:YAG () which is used as a light source for the gravitational wave detector. 相似文献
47.
Marc Delcroix Keisuke Kinoshita Tomohiro Nakatani Shoko Araki Atsunori Ogawa Takaaki Hori Shinji Watanabe Masakiyo Fujimoto Takuya Yoshioka Takanobu Oba Yotaro Kubo Mehrez Souden Seong-Jun Hahm Atsushi Nakamura 《Computer Speech and Language》2013,27(3):851-873
Research on noise robust speech recognition has mainly focused on dealing with relatively stationary noise that may differ from the noise conditions in most living environments. In this paper, we introduce a recognition system that can recognize speech in the presence of multiple rapidly time-varying noise sources as found in a typical family living room. To deal with such severe noise conditions, our recognition system exploits all available information about speech and noise; that is spatial (directional), spectral and temporal information. This is realized with a model-based speech enhancement pre-processor, which consists of two complementary elements, a multi-channel speech–noise separation method that exploits spatial and spectral information, followed by a single channel enhancement algorithm that uses the long-term temporal characteristics of speech obtained from clean speech examples. Moreover, to compensate for any mismatch that may remain between the enhanced speech and the acoustic model, our system employs an adaptation technique that combines conventional maximum likelihood linear regression with the dynamic adaptive compensation of the variance of the Gaussians of the acoustic model. Our proposed system approaches human performance levels by greatly improving the audible quality of speech and substantially improving the keyword recognition accuracy. 相似文献
48.
We achieved preparation of co-continuous titania based monolithic materials using several organic polymer monoliths as pore templates. Firstly, the organic polymer monoliths that had well controlled structures were prepared, and filled the pores of polymer monolith with tetra-n-butyl titanate (titan monomer). The following hydrolysis of the titan monomer resulted in titanium dioxide. The polymer monolith was removed by calcination at elevated temperature. We carefully studied the utility of polymer monolithic template, filling method of the titan monomer, and calcination conditions to realize co-continuous titania monolith. In addition, by the change of domain size (size of a skeleton + size of through a pore) of template, we were able to control domain size of the resulting titania monoliths. 相似文献
49.
J. Xie Y.J. Liu Y. Tang A. Kubo J. Tamaki 《Journal of Materials Processing Technology》2009,209(18-19):6004-6009
Dry electro-contact discharge (ECD) dressing of metal-bonded #600 diamond grinding wheel is proposed for grinding of various granites. As compared to mechanical GC dressing, Dry ECD dressing can not only protrude fine diamond grains from wheel metal-bond without any damage, but also eliminate bond-tail behind the protruded grain. The objective is to understand how the synthetic factors including granite structure, grinding parameters and dressing method influence the ground surface integrity of multi-crystal granite such as surface roughness and surface crack appearance in contrast to homogeneous optic glass. First a micron-scale indentation experiment was carried out to display the growth mechanism of micro-cracks on polished surface, then Dry ECD dressing and mechanical GC dressing were carried out in grinding experiment, respectively, finally surface roughness and micro-surface crack were investigated in connection with granite crystal size, work speed and dressing method. It is found that in almost all cases the multi-crystal granite has always worse ground surface than homogeneous optic glass even if grinding parameter is changed. Moreover, the improvement of ground surface for granite is more sensitive to grain protrusion feature than that for optic glass. Although it is very difficult to find out obvious relationship between surface roughness and grinding parameter such as work speed, it has a good correlation with granite structure such as granite crystal size: it decreases with the increase of the granite crystal size. It is concluded that Dry ECD dressing may more greatly improve the ground surface integrity of various granites than mechanical GC dressing. 相似文献
50.
Wataru Kubo Kunihiko Itoh Shozo Miyazaki David Attwood 《Drug development and industrial pharmacy》2013,39(8):819-825
ABSTRACTThe aim of this study was to evaluate the potential of an in situ gelling pectin formulation as a vehicle for the oral sustained delivery of theophylline and cimetidine. In vitro studies demonstrated diffusion-controlled release of theophylline from 1, 1.5, and 2% w/v pectin gels. Release of this drug from 1.5% w/v pectin gels formed in situ in rabbit stomach was sustained over a period of 12 hours giving a theophylline bioavailability some seven fold higher than when administered from a commercial syrup. In contrast, interactions between cimetidine and pectin led to weak gelation of the pectin sols that prevented any meaningful determination of in vitro release characteristics. Similarly, in vivo release profiles from pectin formulations containing cimetidine were similar to that from a solution of this drug in buffer, indicative of weak gelation. Examination of the content of the rabbit stomach 5 hours after administration of 1.5% w/v pectin sols containing drug confirmed gel formation, but gels containing cimetidine were noticeably softer than those containing theophylline. 相似文献