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101.
Eighteen of 349 cases (5.2 per cent) of bacterial meningitis seen between 1949 and 1973 were hospital-associated (developed after admission to the hospital). The patients were adults, usually males, and developed symptoms and signs of meningitis from 2 to 23 days (mean, 10.1 days) after hospital admission. The diagnosis of bacterial meningitis was made from less than 1 day to 15 days (mean, 4.8 days) after the onset of symptoms. Fourteen of the 18 patients had received antibiotics during the week prior to developing meningitis. Nine (50 per cent) had a chronic, noninfection, underlying illness. Diagnostic or surgical procedures involving the neuraxis or adjacent structures preceded the development of meningitis in 10 of the 18 patients (56 per cent). Only 6 of the 18 patients survived their infection. Prompt recognition, diagnosis, and therapy of hospital-associated meningitis in high-risk patients may reduce the significant mortality.  相似文献   
102.
Intraphase redox kinetics were monitored across the wüstite, Fe1–xO, phase of the iron-oxygen system in CO2-CO and CO2-CO-Ar mixtures at 1062 and 1106° C. Kinetic data expressed in terms of the chemical diffusion coefficient and the equilibration time as a function of composition strongly indicated the importance of a reaction at the gas-oxide interface in the overall reequilibration of a specimen. Both the chemical diffusion coefficient and the equilibration time were found to be inversely proportional to the deviation from stoichiometry. Surface rate constants calculated from initial linear oxidation data were found to decrease as the deviation from stoichiometry increased.  相似文献   
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Beginning with a model of social perception in which the perceiver is assumed to operate according to the conventional canons of statistical inference, it was hypothesized that trait judgments of groups of individuals represented by facial photographs would match the mean values of these photographs judged individually and that confidence and the amount of information required before a judgment is reported will vary inversely with the variance in the set of photographs comprising the group, and directly with the significance of the judgment for the judge. Using different procedures and measures of the dependent variables, 2 experiments were performed which agreed in supporting the hypotheses. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Two-terminal devices which exhibit a type-S (current-controlled) or type-N (voltage-controlled) negative differential resistance can be built using only two bipolar transistors and linear positive resistors without any internal biasing power supply. Two general algorithms are presented in this paper for systematically generating all such devices. Hundreds of negative resistance devices have been derived to date using these algorithms and a selection of these circuits is presented in this paper along with their computer-simulated v-i curves. Laboratory measurements of a few sample circuits agree remarkably well with the computer-simulated results.  相似文献   
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This document is a collection of four working group reports in the areas of digital libraries, document image retrieval, layout analysis, and Web document analysis. These reports were the outcome of discussions by participants at the Fifth IAPR International Workshop on Document Analysis Systems held in Princeton, NJ on 19-21 August 2002.Published online: 16 March 2004  相似文献   
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The concentration and affinity to concanavalin A (ConA) of plasma alpha 1-acid glycoprotein (AGP) and AGP levels in extracts of liver tissues were investigated in specific-pathogen-free chickens infected with the highly virulent HPS-2 strain or virulent reference GBF-1 strain of infectious bursal disease virus. The plasma AGP value in uninfected control 3- to 7-wk-old chickens was 161.8 +/- 25.8 micrograms/ml (mean +/- SD), and ConA-unreactive and ConA-reactive AGP comprised 47% and 63% of total AGP. Increases in AGP levels in plasma and liver extracts were observed in both the HPS-2 and the GBF-1 groups, although albumin levels decreased. The plasma AGP values were higher in the HPS-2 group than in the GBF-1 group through the experimental period. In the HPS-2 group, ConA-reactive AGP reached levels 6.8-fold greater than control values and comprised 80% of total AGP at 4 days post-inoculation. In the lipopolysaccharide group, a great increase in ConA-reactive AGP was observed.  相似文献   
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