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951.
952.
An algorithm is described for processing the results of two- coordinate measurements of a profile representing a partial circle. Information is presented on the instrument structure and on the functions executed by the microprocessor.Translated from Izmeritel'naya Tekhnika, No. 9, pp. 22–24, September, 1993. 相似文献
953.
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
954.
JR Perry SS Deodhare JM Bilbao D Murray P Muller 《Canadian Metallurgical Quarterly》1993,32(2):157-162
Sex hormones have profound effects on immune responses and may influence the outcome of autoimmune diseases such as rheumatoid arthritis (RA). We investigated the effect of gonadal steroids on the production of interleukin-1 (IL-1) and IL-6, cytokines believed to be important in the pathogenesis of RA. Peripheral blood mononuclear cells (PBMCs) were isolated from healthy male donors and male patients with RA, and were stimulated with lipopolysaccharide (LPS) in the presence of different concentrations of 17-beta-estradiol, progesterone or testosterone. In studies of cells from normal male donors, 17-beta-estradiol at pharmacological concentrations (> or = 10(-6) M) enhanced IL-1 and IL-6 secretion as well as the production of cell-associated IL-1. Progesterone and testosterone at similar concentrations inhibited IL-1 secretion but had no significant effect on IL-6 secretion or on the production of cell-associated IL-1. In studies of male RA donors, 17-beta-estradiol failed to enhance IL-1 or IL-6 secretion and progesterone failed to inhibit IL-1 secretion. The inhibitory effects of testosterone, however, appeared to be similar to that in normal donors. It is suggested that 17-beta-estradiol may promote IL-1 and IL-6 production and release, while gestation hormone, progesterone, and testosterone may inhibit IL-1 release in vivo. These data may partly explain the gender and age differences in the incidence of RA and the development of the disease in men with low and androgen levels. 相似文献
955.
BACKGROUND: An important agent of food intoxication is Staphylococcus aureus, that is able to produce enterotoxins. AIM: To detect Staphylococcus aureus contamination in cafeteria food handlers of a Chilean University. SUBJECTS AND METHODS: Nose, throat, hands and nail samples from 87 food handlers were obtained for microbiological examination. RESULTS: Fifty seven subjects (65.5%) were carriers of Staphylococcus aureus. Enterotoxigenic Staphylococcus aureus was found in 36 subjects (41%). The most frequently found enterotoxin was type B (18 samples) followed by type D (12 samples). Men bad a higher frequency of contamination than women (83 and 57% of positive samples respectively). CONCLUSIONS: The frequency of Staphylococcus aureus contamination among food handlers is high and should prompt personal and environmental hygienic measures. 相似文献
956.
957.
19950405 Our investigation on the rheological aspects such as gelling time, specific density, fluidity, viscosity and surface tension of the sol derived from titanium-tetra-isopropoxide (TTIP), water and isopropanol (i-PrOH) has been reviewed in the presence of n,n-dimethylaniline (DMA) as a drying control chemical agent (DCCA). Dry gels derived from DMA stabilized sol were found to be crack free with a larger surface area. The titania gel monolith obtained in the presence of DMA could be processed into rutile at much lower temperatures. 相似文献
958.
Marie-Angele De Looze R. Coronini Monique Legentil P. Jeannin Marie-Hélene Magri 《Scientometrics》1996,36(2):167-183
This paper analyses the determination of visibility of journals in which researchers of INRA (National Institute for Agricultural Research) publish. The corpus is comprised of 671 articles published over a period of four years in 258 journals. The advantage of the method applied for determining the visibility of journals is that it combines two approaches: a) bibliometric indicators (coverage by the ISI-publications and by two specific French databases) and b) experts' opinions (10 economists and sociologists). The main results are: a) There is a convergence between the opinion of the experts and «visibility» in the databases, b) The impact factor confirms the main opinions of the experts. The first journals ranked by the experts and JCR Social Sciences are the same but represent only 40 per cent of the total journals analysed. The other journals were revealed by the experts and French databases.«Whoever seeks to pass a balanced but lucid judgement on the general trends of the activity carried out by the profession to which he belongs, is liable to say either banalities or to hurt his colleagues»The notion which we retain of core is that which is successively and conjointly validated by the experts and by the major databases representative of the field.This study was financed by the Department of Rural Economy and Sociology of INRA. 相似文献
959.
The alignment of six fluorescent materials (p-terphenyl, p-quaterphenyl, p-quinquephenyl, diphenylstilbene, 1,4-bis(2-methylstyryl)benzene, and 1,4-bis-2-(5-phenyloxazolyl)benzene) grown from the vapour phase on to friction-deposited, highly oriented poly(tetrafluoroethylene) (PTFE) films was studied. The dichroic ratio of the fluorescent films produced was determined by polarized spectroscopic fluorescence measurements, and the crystallographic orientation of these materials was determined by transmission electron microscopy. The measured dichroic ratios ranged from 1.7 for diphenylstilbene to 5.0 for the p-quaterphenyl film. Electron diffraction patterns revealed that five of the fluorescent materials grew epitaxially on the single crystal-like PTFE films, the fluorescent crystals adopting particular orientations with respect to the crystallographic planes of PTFE. On the other hand, crystals of 1,4-bis-2-(5-phenyloxazolyl) benzene aligned in a fibre pattern, apparently by a grapho-epitaxial mechanism. 相似文献
960.
Arpaia P. Avallone F. Baccigalupi A. De Capua C. 《IEEE transactions on instrumentation and measurement》1996,45(2):462-466
Two real-time algorithms for active power measurements on Pulse Width Modulation (PWM) electric drives are proposed. The former is an off-line algorithm reducing truncation error through an accurate signal period estimation and a proper window. The second is an on-line algorithm based on a low-pass IIR digital filter with an optimized transient phase. Numerical results of the metrological characterization of such algorithms, aimed to suggest criteria for their use, are presented. The experimental results of tests carried out on an actual drive confirm numerical simulations and are in perfect agreement with those of a well-acclaimed algorithm 相似文献