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991.
G Stoll S Müller B Schmidt P van der Meide S Jung KV Toyka HP Hartung 《Canadian Metallurgical Quarterly》1993,142(6):1866-1875
This study reports the cellular localization of interferon-gamma (IFN-gamma) and MHC class II antigen (Ia) in the spinal cord of rats with experimental autoimmune encephalomyelitis induced by adoptive transfer of myelin basic protein-specific T cells. Numerous IFN-gamma-positive cells, stained with two different monoclonal antibodies against IFN-gamma, were present from days 3 to 7 after cell transfer. Their number was greatly reduced on day 10. A subpopulation of T cells was IFN-gamma positive. Moreover, a large number of ED1-positive macrophages contained IFN-gamma immunoreactivity. The transient presence of immune cells containing IFN-gamma immunoreactivity in experimental autoimmune encephalomyelitis suggests a pathogenic role of this cytokine in immune-mediated demyelination of the central nervous system. 相似文献
992.
993.
SW Mamber B Kolek KW Brookshire DP Bonner J Fung-Tomc 《Canadian Metallurgical Quarterly》1993,37(2):213-217
Eight quinolones were examined for their bacterial mutagenicity in the Ames Salmonella TA102 assay and for their effects in other bacterial genotoxicity assays. In the quantitative Ames plate incorporation assay, all eight quinolones induced His+ deletion reversion in Salmonella tester strain TA102, with maximum reversion observed at about two to eight times the MIC. The quinolones also induced the SOS response. At quinolone concentrations close to the MIC, SOS cell filamentation gene sulA was induced in sulA::lacZ fusion strain Escherichia coli PQ37. RecA-mediated cleavage of lambda repressor in lambda::lacZ fusion strain E. coli BR513 was measurable at about 10 times the MIC, though no induction occurred at 20 micrograms of nalidixic or oxolinic acid per ml. Genotoxicity of quinolones also was observed in the Bacillus subtilis DNA repair assay, in which the mutant strain M45 (recA) was more susceptible to quinolones than its parent strain, H17 (rec+). The results from these analyses indicate that quinolones induce SOS functions and are mutagenic in bacteria; these properties correspond to their antimicrobial activities. 相似文献
994.
A Almeida N Kokalj-Vokac D Lefrancois E Viegas-Pequignot M Jeanpierre B Dutrillaux B Malfoy 《Canadian Metallurgical Quarterly》1993,91(6):538-546
To determine possible relationships between DNA hypomethylation and chromosome instability, human lymphoblastoid cell lines from different genetic constitutions were studied with regard to 1) uncoiling and rearrangements, which preferentially affect the heterochromatic segments of chromosomes 1 and 16; 2) the methylation status of the tandemly repetitive sequences (classical satellite and alphoid DNAs) from chromosomes 1 and 16, and of the L1Hs interspersed repetitive sequences. The methylation status largely varied from cell line to cell line, but for a given cell line, the degree of methylation was similar for all the repetitive DNAs studied. Two cell lines, one obtained from a Fanconi anemia patient and the other from an ataxia telangiectasia patient were found to be heavily hypomethylated. The heterochromatic segments of their chromosomes 1 and 16 were more frequently elongated and rearranged than those from other cell lines, which were found to be less hypomethylated. Thus, in these lymphoblastoid cell lines, alterations characterized by uncoiling and rearrangements of heterochromatic segments from chromosomes 1 and 16 seem to correlate with the hypomethylation of their repetitive DNAs. Two-color in situ hybridizations demonstrated that these elongations and rearrangements involved only classical satellite-DNA-containing heterochromatin. This specificity may be related to the excess of breakages affecting the chromosomes carrying these structures in a variety of pathological conditions. 相似文献
995.
The purpose of all injury care is to restore patients' pre-injury functioning and to facilitate the return to normal activities. The aim of this prospective study was to describe and analyse psychiatric factors and other patient-related characteristics which influence long-term results after moderate injuries. One hundred and sixty-nine injured patients were randomized to go through a comprehensive psychosocial research protocol and to participate in the 12 month follow up. The 49 patients lost to follow-up differed significantly from all other patients. They were more often single, blue-collar workers with a lower educational level and had a less favourable psychosocial background, including alcohol abuse. The 120 patients who completed the follow-up were divided in two groups: the non-recovered group (NR, N = 58), patients reporting limitations in performing their work and/or limitations in carrying out housework and/or in social life, and the recovered group (R, N = 62), patients reporting full recovery or only minor limitations in exercise or sports 12 months after the injury. The NR patients were older (P < 0.05), had a slightly higher injury Severity Score (P < 0.01) and showed signs of depression both during the acute post-injury period and at 1 year follow up (P < 0.001). The multivariate analysis showed that measurements of pain and depression during the acute post-injury period were associated with the functional outcome after 12 months. Co-operation between injury and psychiatric units should be developed to identify patients needing psychosocial or psychiatric support during the early phase of rehabilitation. 相似文献
996.
Edgar B. Gutoff 《Drying Technology》1996,14(7):1673-1693
A complete model for the drying of coated webs. as implemented in the spreadsheet DRYWEB for Lotus and for Excel, is described. The model predicts the temperatures and solvent levels throughout the length of the dryer. The initial transient as the coated web approaches the equilibrium temperature in the consiant rate period is calculated. The coating is divided into slices for a finite difference calculation of solvent diffusion to the surface, using a simple free volume model of diffusion. The semi-empirical constants needed can be found from one or two trial runs. The possible use of infra-red heating in addition to convection heating is included in both the constant and falling rates. The calculation of infra-red energy is discussed. The model assumes that the temperature is uniform from the top of the coating to the bottom of the base, and that assumption is justified. 相似文献
997.
Durhuus T. Mikkelsen B. Joergensen C. Lykke Danielsen S. Stubkjaer K.E. 《Lightwave Technology, Journal of》1996,14(6):942-954
Following a brief introduction to the applications for wavelength conversion and the different available conversion techniques, the paper gives an in depth analysis of cross gain and cross phase wavelength conversion in semiconductor optical amplifiers. The influence of saturation filtering on the bandwidth of the converters is explained and conditions for conversion at 20 Gb/s or more are identified. The cross gain modulation scheme shows extinction ratio degradation for conversion to longer wavelengths. This can be overcome using cross phase modulation in semiconductor optical amplifiers that are integrated into interferometric structures. The first results for monolithic integrated interferometric wavelength converters are reviewed, and the quality of the converted signals is demonstrated by transmission of 10 Gb/s converted signals over 60 km of nondispersion shifted single mode fiber 相似文献
998.
OBJECTIVE: We report a case of candidiasis of the upper urinary tract that presented as acute renal failure associated with septic syndrome. The patient initially required hemodialysis. Right hydronephrosis and perirenal collection were observed on ultrasound examination. METHODS: A percutaneous nephrostomy was performed. Nephrostomy urine cytology and cultures were positive for Candida tropicalis. An anterograde pyelography showed a 'fungus ball' in the urinary tract. RESULTS: Therapy with oral fluconazole and percutaneous amphotericin B achieved excellent results. CONCLUSIONS: Candidiasic urinary infection of the upper urinary tract often produces obstructive uropathy requiring percutaneous nephrostomy, which can also be used to instill amphotericin B. Combination therapy with amphotericin B and fluconazole can achieve excellent results. 相似文献
999.
As the number of fuzzy logic applications increases, demand for faster architectures will grow. Our design for a VLSI fuzzy processor uses fuzzy inference techniques that optimize processing time. Preprocessing that reduces the number of rules to be processed, parallel computation of active rule degrees of activation, and scalability are major features of this architecture. The journal issue contains a concise summary of this article. The complete article is linked to Micro's home page on the World Wide Web (http://www.computer.org/pubs/micro/micro.htm) 相似文献
1000.
Rachinger's method of separating 1 and 2 doublets in X-ray emission spectra is applied for the first time to separate the superimposed doublets due to spin-orbit coupling. This method has been applied to separate closely lying doublets such as (Ag 4p3/2and Ag 4p1/2, (Ni 3p3/2and Ni 3p1/2) and (Cu 3p3/2and Cu 3p1/2). The intensities ratios of the separated peaks are measured and compared with the ratios obtained from a first-order calculation. An excellent agreement between the measured and calculated ratios are obtained. Residual background intensities compared with the estimated values are found to agree within certain uncertainties. 相似文献