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排序方式: 共有366条查询结果,搜索用时 31 毫秒
81.
Y Ohosone Y Okano H Kameda T Fujii N Hama M Hirakata T Mimori M Akizuki Y Ikeda 《Canadian Metallurgical Quarterly》1997,24(12):2299-2303
OBJECTIVE: To determine the clinical features of methotrexate (MTX) pneumonitis in patients treated for rheumatoid arthritis (RA). METHODS: The medical records of 284 patients with RA who had been treated with oral MTX (mean followup 33.2 mo) were reviewed retrospectively. RESULTS: MTX induced interstitial pneumonitis developed in 6 patients (2.1%). The affected patients were significantly older than those without MTX pneumonitis (67.3 +/- 9.8 vs 52.4 +/- 12.6 yrs, respectively; p < 0.005). The cumulative MTX dose ranged from 65 to 580 mg at the time pneumonitis developed. Five of the patients (83%) had preexisting interstitial abnormalities, while only 29 of the 278 patients without MTX pneumonitis (10%) had such abnormalities (p < 0.001). The frequency of adverse effects due to previous treatment with disease modifying antirheumatic drugs (DMARD) was 66.7% in MTX pneumonitis patients and 14.3% in the other 278 patients (p < 0.01). CONCLUSION: Advanced age, preexisting interstitial abnormalities, and previous adverse reactions to DMARD may be associated with MTX pneumonitis. Patients with these characteristics require careful monitoring during MTX therapy. 相似文献
82.
A locally iterative learning (LIL) rule is adapted to a model of the associative memory based on the evolving recurrent-type neural networks composed of growing neurons. There exist extremely different scale parameters of time, the individual learning time and the generation in evolution. This model allows us definite investigation on the interaction between learning and evolution. And the reinforcement of the robustness against the noise is also achieved in the evolutional scheme. 相似文献
83.
Functions of genes regulating the development of Drosophila peripheral nervous systems are summarized herein. These genes can be classified into 6 groups: <1> prepattern genes, <2> proneural genes, <3> neurogenic genes, <4> neuronal precursor genes, <5> neuronal precursor type selector genes, and <6> cell-division and lineage genes. The mechanisms described herein provide excellent paradigms in the regulation of the development of other tissues in Drosophila, as well as in other organisms, including vertebrates. The roles of two different inhibitory mechanisms, i.e. Notch-signaling and Argos, in the development of Drosophila neural precursor cells are also discussed. 相似文献
84.
Membranous obstruction of the inferior vena cava at the suprahepatic level is rare. The present report summarizes direct operative repair. A review of alternative therapeutic strategies is presented. 相似文献
85.
Fukawa M. Kawai T. Okano Y. Sakuma S. Asai S. Kanaoka M. Yamanouchi H. 《Power Delivery, IEEE Transactions on》1996,11(2):627-634
500-kV XLPE-insulated cable with an insulation thickness of 27 mm has been developed for long-distance transmission lines. Basic studies on 500-kV XLPE cable have shown that contaminants in the insulation may be the factor determining electrical performance. This hypothesis is justified by the good correlation obtained between statistical estimations of the size of the largest contaminant in the insulation and the electrical characteristics of full-sized cables. Voltage-withstand and long-term tests have confirmed the design values for minimum breakdown stress, for AC and impulse voltage, and for the degradation coefficients 相似文献
86.
A miniature-size pyramidal-shape diamond field emitter array has been fabricated using the mold technique. The tip radius of each pyramid was found to be less than 2000 Å from SEM observation and the fabricated array was identified as diamond from the results of AES and Raman spectroscopy. The array was placed in a high vacuum pumping system with the basic pressure of 10-7 Torr, and the emission property was measured using a Au ball anode with 100 μm in diameter. The distance between the anode and the array was set up to 100 μm throughout the measurements. As a result, the emission current of 1×10-6 A was observed at the applied voltage of 2400 V 相似文献
87.
H Hamada M Sakatani M Nishioka M Akira S Yamamoto E Ueda Y Okano Y Nakamura S Sone 《Canadian Metallurgical Quarterly》1997,35(6):692-697
STUDY OBJECTIVE: To review the epidemiology of hepatitis C virus (HCV) infection among injecting drug users (IDUs) in Australia, and consider needs for further research and prevention policies and programmes. DESIGN: (1) Review of the results of surveillance for HCV; (2) review of published literature on prevalence, incidence, and risk factors for HCV among IDUs; and (3) reconstruction of incidence rates from prevalence studies of HCV in IDUs. SETTING AND PARTICIPANTS: Field and clinic based studies of IDUs in Australia. MAIN RESULTS: HCV has been present at high prevalences (of the order of 60-70%) in populations of Australian IDUs since at least 1971. Duration of injecting and main drug injected were the main predictors of seropositivity, the latter possibly a surrogate for frequency of injecting and both together as surrogate for cumulative numbers of times injected. Risk of infection begins with first injection and continues as long as injecting does. Current incidence is approximately 15 per 100 person years, and up to 40 per 100 person years in some subpopulations. Incidence may have decreased through the 1980s as a result of behaviour change in relation to HIV, as it has for hepatitis B, but not significantly so. CONCLUSIONS: Control of HCV infection in Australia will depend on effectiveness of measures to control HCV spread among IDUs. This will be a greater challenge than the control of HIV in this population has been. Needs identified include improved surveillance, especially for recently acquired infection, better understanding of exact transmission modes, and urgent improvement in prevention strategies. 相似文献
88.
Droplet combustion is considered one of the combustion figurations in sodium-fire events; the detailed combustion mechanism by which it occurs is evaluated by a developed computational fluid dynamic (CFD) simulation code, called COMET, in which the extended MAC method is employed for calculating the reacting compressible flow coupled with the multi-component diffusion of chemical species. A single droplet combustion in steady-airflow was simulated using the COMET to analyze: (1) the spatial distributions of heat rate and temperature, and (2) the formation, decomposition, and transfer of combustion products. Next, a free-falling droplet combustion experiment was simulated for code validation, where the evaluated falling-velocity and burnt-mass showed good agreement with the experimental values. 相似文献
89.
M Tomimatsu H Endou H Takahashi D Iga Y Kato N Tamai H Nakajima A Okano H Mori H Hisatomi 《Canadian Metallurgical Quarterly》1997,12(9-10):629-632
In patients receiving interferon therapy for chronic hepatitis C, serum hepatitis C virus (HCV) RNA often reverts from an undetectable to a detectable form after completion of treatment. Detection of the negative strand of HCV-RNA in liver tissue is regarded as an index of viral proliferation. Therefore, we investigated changes in the hepatic negative-strand HCV-RNA following interferon therapy to determine whether this parameter could predict the long-term response to treatment. The subjects of this study were 27 patients with chronic active hepatitis C. Serum positive-strand and hepatic tissue negative-strand HCV-RNA were detected using polymerase chain reaction. At the completion of interferon treatment, serum HCV-RNA was not detected in 21 patients. One year following treatment it remained undetectable in 14 of these patients but it had reverted to a detectable form in seven. The 14 patients in whom hepatic negative-strand RNA was not detected between 2 weeks and 12 months after treatment, had not relapsed after another year. In the 13 remaining patients, negative-strand RNA was found in liver tissue and serum RNA either reverted to a detectable form or remained detectable throughout. From these findings, we conclude that the detection of negative-strand HCV-RNA in liver tissue 2 weeks after the completion of interferon therapy is useful for predicting the long-term effect of therapy. 相似文献
90.
H von Recum A Kikuchi M Okuhara Y Sakurai T Okano SW Kim 《Canadian Metallurgical Quarterly》1998,9(11):1241-1253
A cross-linkable co-polymer of UV-sensitive 4-(N-cinnamoylcarbamide)methylstyrene (CCMS) and N-isopropylacrylamide (NIPAAm), was applied to porous tissue culture inserts. Surface chemical analyses of the inserts show an introduction of a thermally responsive polymer comparable to that on similarly incorporated non-porous polystyrene surfaces. Contact angle measurements as well as atomic force microscopy show a surface change in response to changing temperature in an aqueous environment, from hydrophilic, extended polymer chains below 32 degrees C to a dense hydrophobic film above 32 degrees C. Cell growth on porous inserts allowed measurement of cell expression, such as transepithelial resistance and fluid transport, which are not observable on cells from non-porous surfaces. Cultures of retinal pigmented epithelium (RPE) were able to restore an environment similar to in vivo by forming a tight junction barrier membrane upon confluence at 37 degrees C, as observed by changes in morphology, transepithelial resistance, and directionally-specific fluid transport. In addition, cells cultured on these surfaces detached as an oriented polarized sheet when the inserts were brought to 20 degrees C. This cell sheet was transplanted to other tissue culture surface without polymer detachment or dissolution, or cell damage caused by traditional detachment methods using proteolytic enzymes. 相似文献