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51.
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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   
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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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The properties of chemically cured and light-cured composite resins were recorded at baseline and at intervals over seven years, while the materials were exposed to controlled storage conditions as well as to various conditions typical of clinical situations. For chemically cured resins in clinical conditions, mechanical properties decreased, and working and setting times increased over four years; if refrigerated (controlled), properties remained constant past seven years. For light-cured resins, test results were constant over the entire seven-year test period regardless of storage conditions. An accelerated aging protocol was developed to allow for the evaluation of the relative storage stability of new and similar materials.  相似文献   
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The growing use of antibody-based separation methods has paralleled the expansion of immunochemical detection methods in moving beyond the clinical diagnostic field to applications in environmental monitoring. In recent years high-performance immunoaffinity chromatography, which began as a separation technique in biochemical and clinical research, has been adapted for separating and quantifying environmental pollutants. Bioaffinity offers a selective biological basis for separation that can be incorporated into a modular analytical process for more efficient environmental analysis. The use of immunoaffinity chromatography for separation complements the use of immunoassay for detection. A widely used immunochemical detection method for environmental analyses is enzyme immunoassay. The objective of this paper is to review the status of bioaffinity-based analytical procedures for environmental applications and human exposure assessment studies. Environmental methods based on bioaffinity range from mature immunoassays to emerging techniques such as immunosensors and immunoaffinity chromatography procedures for small molecules.  相似文献   
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张雪 《低压电器》1999,(5):48-51
形状记忆合金与以金属都具有具有随温度变经而发生变化的特性,本文就它们的变经机制,性能,应用场合等进行比较,使这两种材料在使用时更好地发挥其作用。  相似文献   
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