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Abstract To overcome problems associated with Western blotting of denatured proteins, we have used quantitative immunoelectrophoretic techniques to perform functional analysis of the Neisseria gonorrhoeae common antigen. Using these techniques, we show (a) that Neisseria gonorrhoeae expresses an antigen that is cross-reactive with the common antigen of Pseudomonas aeruginosa and Legionella micdadei and with the GroEl-like protein of Chlamydia , and (b) that this N. gonorrhoeae common antigen has lectin-like activity and can be precipitated with three different sugars immobilized on agarose beads: α- d -glucosamine, maltose and fucose.  相似文献   
895.
Oliver Krüger 《Bird Study》2013,60(2):125-132
Capsule Variation in reproduction between territories was strongly influenced by intra- and interspecific competition, phenotype, levels of rainfall and human disturbance.

Aims To assess the relative importance of competition, food, habitat quality, weather and phenotype as predictors of variation in reproduction in Buzzard.

Methods Annual breeding data were collected from 1989 to 1996 in a 300-km2 study area and related to 35 independent variables through multivariate regression models.

Results Significant predictors of variation in reproduction between territories (78% variance explained) were variables describing intra- and interspecific competition, plumage morph, laying date, precipitation levels and anthropogenic disturbances in the breeding territory. Competition and plumage morph seem to be particularly important, as these variables explained a high level of variation (81%) in the 1996 reproduction of this population.

Conclusion The potential importance of competition, plumage morph and precipitation for reproduction in this Buzzard population is emphasized.  相似文献   
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本文用自行研制的883L型增菌培养基对51例次慢性前列腺炎患者的前列腺液作L型培养,结果检出L型细菌27例,占52.9%,经返祖和药物敏感性测定,证明本组L型细菌特性与其他来源的L型细菌基本相符,提示慢性前列腺炎的病因、病理机制可能与细菌L型的感染相关。  相似文献   
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Summary The effects of temperature and photoperiod acclimation upon the morphology of carp intestinal mucosa have been studied using morphometric techniques. Carp intestine showed an absence of anatomical regionalisation. There was a gradual reduction in the dimensions of villi along the tract. The decrease in the dimensions of the villi was greatest in the anterior half. Temperature acclimation had no effect on intestinal-somatic indices. Acclimation to 10° C or 30° C resulted in large differences in the dimensions of villi. Cold acclimation produced significant increases in mean villus height and breadth along the entire intestine. These villus shape changes resulted in a 58% increase in total mucosal surface area and a 102% increase in total volume of villi in cold-acclimated fish relative to warm-acclimated fish. Surface area of the unmodified intestinal tube increased with cold acclimation by 28%. The total number of villi remained unchanged by thermal acclimation. Because normalisation to a nominal surface area does not take account of the possibility of differentially developed mucosal surfaces in differently acclimated animals, experiments comparing transepithelial transport rates of differently-acclimated fish, using unstripped preparations, overestimates the differences in area-specific transport capacity.  相似文献   
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