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991.
Rolf Erhard und Michael Wink 《Journal of Ornithology》1987,128(4):477-484
Zusammenfassung Die Brutverbreitung der Vögel im Großraum Bonn wurde 1975 und 1985 in jeweils 221 Minutengitterfeldern von je 2,2 km2 Größe kartiert. Statistisch signifikante Zunahmen besetzter Gitterfelder wurden für 9 Arten, Abnahmen für 22 Arten registriert, die z. T. auch andernorts festgestellt wurden. Unter Verwendung von Kartierungsdaten 1974–1978 konnte bei 14 Arten eine signifikante Änderung (Zunahmen: Sperber, Habicht, Singdrossel; Abnahmen: Steinschmätzer, Rebhuhn, Schafstelze, Grauammer, Mehlschwalbe, Feldsperling, Fasan, Dorngrasmücke, Hänfling, Feldlerche und Zaunkönig) nachgewiesen werden. Die Untersuchung zeigt, daß die Rasterkartierung gut geeignet ist, Aussagen über großflächige und langfristige Populationsveränderungen zu machen.
Fluctuation of breeding populations in the area of Bonn: Analysis of grid mapping in 1975 and 1985
Summary The distribution of breeding birds in the area of Bonn was mapped in 1975 and 1985 in 221 grids of 2.2 km2 size each. These data were analyzed to see whether fluctuations in the breeding populations occurred during the 11 years. It was based on the assumption that strong population changes should be reflected in the number of grids occupied by a species. Statistically significant increases were recorded for 9 species, decreases for 22 species. Taking other grid-map data from 1974 til 1978 (Wink 1980) into account, a continuous and significant trend could be established for 14 species (increase:Accipiter nisus, A. gentilis, Turdus philomelos; decrease:Oenanthe oenanthe, Perdix perdix, Motacilla flava, Emberiza calandra, Delichon urbica, Passer montanus, Phasianus colchicus, Sylvia communis, Acanthis cannabina, Alauda arvensis, Troglodytes troglodytes). This study shows that grid-mapping may provide valuable data on population trends of breeding birds.相似文献
992.
Purified enterotoxin from the bacterium Clostridium perfringens rapidly decreased the hormonally induced uptake of α-aminoisobutyric acid in primary cultures of adult rat hepatocytes. At 5 min after toxin addition the decrease in α-aminoisobutyric acid uptake appeared not due to increased passive permeation (estimated with l-glucose) or to increased α-aminoisobutyric acid efflux. When short uptake assay times were employed a depression of α-aminoisobutyric acid influx was observed in toxin-treated hepatocytes. The depression of α-aminoisobutyric acid influx was correlated with a rapid increase in intracellular Na+ (estimated using 22Na+) apparently effected by membrane damage. In contrast, the uptake of cycloleucine in the presence of unlabeled α-aminoisobutyric acid (assay for Na+-independent amino acid uptake) by hepatocytes treated with toxin for 5 min was decreased to only a small extent or not at all depending upon experimental design. At later times, C. perfringens enterotoxin increased the exodus of l-glucose, and α-aminoisobutyric acid from pre-loaded cells indicating that the toxin effects progressive membrane damage. When enterotoxin was removed by repeated washing after 5–20 min the decay of α-aminoisobutyric acid uptake ceased and appeared to undergo recovery towards the hormonally induced control level. The degree of recovery of α-aminoisobutyric acid uptake was inverse to the length of time of exposure to toxin. Adding at 10 min specific rabbit antiserum against C. perfringens enterotoxin without medium change also reversed the effect of toxin on increased intracellular 22Na+, and on the exodus (from preloaded cells) of α-aminoisobutyric acid, L-glucose, and . 相似文献
993.
Abstract Murine monoclonal antibodies (mAbs) were selected against a cell wall glycoprotein of Saccharomyces cerevisiae . One of the mAbs (92-276/018) specifically identified S. cerevisiae and the sibling species S. paradoxus, S. pastorianus and S. bayanus in immunofluorescence studies and immunoblot analyses, while no other yeast genera except Saccharomyces were recognized. Further analysis indicated that the mAb 92-276/018 reacts with an epitope in the carbohydrate chain of the cell wall glycoproteins. 相似文献
994.
995.
Michael Landry 《CMAJ》1977,116(12):1392-1394
Although odontogenic keratocysts are benign they are often locally destructive and tend to recur after conservative surgical treatment. They must therefore be distinguished from other cysts of the jaw. Keratocysts possess outpouchings and microscopic daughter cysts from which recurrences may arise. Histologic examination is essential for diagnosis since the appearances on roentgenograms and at operation usually do not reveal the true nature of the lesion. Since many nondental surgeons and pathologists are unaware of odontogenic keratocysts a case is presented in which surgical treatment was originally conservative and finally relatively radical. 相似文献
996.
997.
998.
Using sensitive radio-enzymatic assays, levels of plasma total catecholamines and norepinephrine in rats change dramatically with changes in body temperature. The decrease in plasma catecholamines induced by warming the animal is reflected in an apparent arterio-venous difference when arterial blood is obtained at room temperature and tail sampling is aided by heat induced vasodilation. Combined blockade of extraneuronal and neuronal uptake reduces this arterio-venous difference. Blood samples obtained from the decapitated trunk of the rat contain similar levels of plasma catecholamines as those obtained from indwelling carotid catheters. Blood levels of dopamine-betahydroxylase were similar whether obtained by venous sampling during heat-induced vasodilation, decapitation or indwelling arterial cannula. 相似文献
999.
1000.
John H. Pazur Michael E. Tay Beverly A. Pazur Frank J. Miskiel 《Journal of Protein Chemistry》1987,6(5):387-399
Sets of isomeric anti-lactose antibodies with specificity for the lactose units of a cell wall polysaccharide fromStreptococcus faecalis strain N were induced in rabbits immunized with a vaccine of nonviable cells of the organism. Such sets of anti-lactose antibodies
were isolated from the serum of immunized animals by affinity chromatography on lactosyl-Sepharose. Gel electrofocusing experiments
showed that the preparations consisted of multiprotein components. One preparation of antibodies of 13 isomers was separated
into homogeneous components by liquid isoelectrofocusing. The individual isomeric antibodies exhibit specificity for the lactose
units of the antigenic polysaccharide, possess isoelectric points in the range of 5.9–8.0, and belong to the IgG class of
immunoglobulins, and each member yields one light chain and one heavy chain on dissociation in sodium dodecyl sulfate (SDS)
and mercaptoethanol. These results have been interpreted as evidence for the assembly of the chains of isomeric antibodies
by a single-chain pairing mechanism. 相似文献