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971.
972.
Bacterial cell wall components such as lipopolysaccharide, a variety of membrane proteins, murein, and lipoprotein can act as immunoadjuvants for bacterial vaccines, thus enhancing protection from bacterial infections. Synthetically prepared N-terminal parts of the lipoprotein from Enterobacteria carrying three fatty acid residues or lipopeptide analogs containing one to four aminoacids bound to S-glycerylcysteine act as potent immunoadjuvants in vivo in combination with or covalently linked to antiges. Here we demonstrate that the supplementation ofSalmonella vaccines with these synthetic lipopeptides significantly enhances their vaccine efficiency in mice. Variations in the native lipopeptide structure regarding chain length and amino acid sequence of the peptide moiety, as well as modifications of the lipoamino acid, lead to reduction or even complete loss of the adjuvant activity. The immunoadjuvant properties of the lipopeptides as described here are mediated by an enhancement of the humoral immune response. 相似文献
973.
Stefan Pudenz Rainer Brüggemann Kristina Voigt Gerhard Welzi 《Umweltwissenschaften und Schadstoff-Forschung》2003,15(1):20
Zur Unterstützung von Bewertungs- und Entscheidungsprozessen über die Nachhaltigkeit von Managementstrategien, deren Auswirkungen
durch unterschiedlich dimensionierte Indikatoren gemessen werden, gibt es verschiedene mathematische Methoden. In diesem Beitrag
werden die Prinzipien dieser sog. multikriteriellen Bewertungs- und Entscheidungshilfeinstrumente beispielhaft anhand einer
Auswahl von Strategien für ein Nachhaltiges Wassermanagement vorgestellt, sowie Vor- und Nachteile herausgearbeitet. Es wird
gezeigt, dass sich die Verfahren insbesondere in Transparenz, Objektivit?t und durch den Grad an Partizipation durch Akteure
z.T. erheblich unterscheiden. W?hrend die Hassediagrammtechnik sich an den naturwissenschaftlich begründbaren Datenmatrix
orientiert und somit eine objektive und transparente Bewertung und Datenanalyse liefert, haben Konkordanzanalyse, Nutzwertanalyse,
PROMETHEE und AHP ihre St?rken in der M?glichkeit, Akteure bzw. Stakeholder am Entscheidungsprozess partizipieren zu lassen.
*** DIRECT SUPPORT *** A00OI029 00003 相似文献
974.
O. N. Luk’yanova 《Russian Journal of Ecology》2006,37(3):205-209
The functional state of the indicator species, the Gray mussel Crenomytilus grayanus (Bivalvia), has been analyzed in five areas of Peter the Great Bay exposed to anthropogenic pollution. The following indices of the state of mussels have been used: molecular biomarkers of energy metabolism—Na+,K+-ATPase, Mg2+-ATPase, and total ATPase activity—as well as the level of lipid peroxidation (LPO) and glutathione concentration in the hepatopancreas, gills, and gonads of mussels. The activity of ATPases, LPO level, and glutathione concentration significantly change in mussels from polluted areas relative to those in mussels from a conventionally unpolluted area (a bay in the Far Eastern State Marine Reserve). The molecular biomarkers used in the study provide reliable information on animal metabolism in impact areas. With consideration of the data obtained, it is concluded that the state of mussels in polluted areas is impaired. 相似文献
975.
E. G. Plotnikova D. O. Rybkina L. N. Anan’ina O. V. Yastrebova V. A. Demakov 《Russian Journal of Ecology》2006,37(4):233-240
Microorganisms capable of degrading monocyclic and polycyclic aromatic hydrocarbons and several chlorinated aromatic compounds were isolated from soils polluted with industrial waste from chemical plants. They were identified as representatives of the genera Pseudomonas, Flavobacterium, Alcaligenes, Rhodococcus, Microbacterium, Cellulomonas, Arthrobacter, and Brevibacterium. Among them, bacteria capable of utilizing xenobiotics in a wide range of ambient temperatures and pH and in the presence of high sodium chloride concentrations were revealed. 相似文献
976.
977.
978.
979.
Walter Klingmüller 《Die Naturwissenschaften》1979,66(4):182-189
Genetic engineering has ushered in a new era in biology. Although many problems are still to be solved, there are examples that point to a possible later application for the benefit of mankind: Bacteria can be manipulated to degrade crude-oil spillages, to produce human insulin and to bind nitrogen from the air. If all the bacteria that are indigenous to agricultural soils could be made to bind nitrogen, an increase in soil fertility might well result. 相似文献
980.
O. Hildingson 《Environment international》1982,8(1-6)
Radon daughter levels have been monitored in 12,000 Swedish dwellings during the last two years. In 1979 the Swedish Government introduced temporary limits for the radon daughter concentration in dwellings. For existing buildings this limit is 400 Bq/m3 (0.11 WL). Two different methods were used to monitor the radon daughter concentration. The majority of the houses presented in this paper were monitored using a track-etch detector; some houses were tested using a filter sampling technique while the ventilation rate was determined. Close to 15% of the investigated houses have a radon daughter concentration higher than 400 Bq/m3. The majority of these houses were one-family houses. Almost 10% of this group has a concentration above 1000 Bq/m3 (0.27 WL). The results from this study show that the two most important sources for radon in buildings are building materials and the ground. 相似文献