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121.
Peter Sackl und Georg Rauer 《Journal of Ornithology》1987,128(4):491-494
Zuammenfassung Im niederösterreichischen Waldviertel (200–700 m üNN) stieg der relative Anteil einjähriger von 17,9 auf 50% aller revierverteidigenden Hausrotschwanz- mit zunehmender Meereshöhe. Die Zunahme betrifft vor allem einjährige dercairei-Morphe, während dieparadoxus-Morphe in geringerer Anzahl und gleichförmiger als in allen Höhenbereichen auftrat.
The portion of first-year males in breeding populations of Black Redstarts (Phoenicurus ochruros) and their altitudinal distribution in the Waldviertel, Lower Austria
Summary In 1986, between April 13 and July 5, breeding territories of male Black Redstarts were mapped in Lower Austria (200–700 m NN), with regard to their age (first-year or older) and the plumage types of first-year (femalelike or adult malelike). Due to a greater percentage of femalelike subadult (cairei-type) in higher altitudes, the proportion of first-year was found to increase from 17,9 per cent at 200–300 m to 50 per cent above 600 m. On the contrary adultlike first-year (paradoxus-type) are evenly distributed in smaller numbers over the whole altitudinal range.相似文献
122.
Peter J. Syapin Terry Ritchie Lorna Noble Ernest P. Noble 《Journal of neurochemistry》1987,48(4):1285-1290
The relationship between the stability of potential neurochemical markers and autolysis time was studied at 4 degrees C and 25 degrees C using postmortem brain samples from two rat strains. In general, qualitatively similar results were obtained with either N/Nih or Sprague-Dawley rats; however, quantitative differences were often observed, particularly in regard to benzodiazepine receptor changes. For every enzyme activity or binding property examined, no significant change was found when brains were kept at 4 degrees C for up to 72 h prior to freezing at -70 degrees C. Na,K-ATPase and low-affinity Ca-ATPase activities were also stable in brains kept at 25 degrees C for up to 72 h. Mg-ATPase activity was reduced in brains kept at 25 degrees C for 24 and 48 h. [3H]Guanidinoethylmercaptosuccinic acid [( 3H]GEMSA) binding to enkephalin convertase in the cytosol was not significantly changed in brains kept at 25 degrees C; however, a small increase was seen for [3H]GEMSA binding to the membrane fraction at 24, but not 48 and 72 h postmortem. [3H]Quinuclidinyl benzilate [( 3H]QNB) binding to muscarinic cholinergic receptors decreased in brains kept at 25 degrees C for 72 h. Opioid receptor binding also decreased in brains kept at 25 degrees C. Using [3H]2-D-alanine-5-D-leucine enkephalin to label delta opioid receptors, a statistically significant decrease in binding was observed as early as 6 h postmortem, and was completely abolished after 72 h at 25 degrees C. In contrast, [3H]naloxone binding was unchanged after 24 h at 25 degrees C, but was decreased after 48 and 72 h.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Effect of Bacteriophage on Colonization of Sugarbeet Roots by Fluorescent Pseudomonas spp 总被引:2,自引:1,他引:1 下载免费PDF全文
The colonization potential of two fluorescent Pseudomonas strains (M11/4, B2/6) that exhibit antifungal activity in vitro was studied on the roots of sugarbeet plants in a clay loam soil. The cell density of the introduced bacteria declined on the root system over a 16-day test period in nonsterile soil. Strain B2/6 declined at a significantly faster rate compared with M11/4. This loss in viability and difference in colonization ability between M11/4 and B2/6 was not observed in sterile soil. Nutrient deprivation induced by indigenous microorganisms was excluded as a key factor involved in the decline of the introduced bacteria on the basis that strains M11/4 and B2/6 retained viability when subjected to nutrient starvation conditions over a 16-day period. Experiments designed to test whether antagonism by indigenous microorganisms was responsible for the decline in the introduced fluorescent Pseudomonas sp. population revealed the presence of large numbers of bacteriophage in the soil capable of lysing strain B2/6. Reconstitution experiments carried out with sugarbeet seedlings inoculated independently with strains M11/4 and B2/6 and grown in sterile soil to which a soil phage filtrate had been added showed a significant decrease in the viability of strain B2/6 relative to M11/4. Phage antagonistic toward strain B2/6 were detected in 43% of soils taken from the major sugarbeet growing regions of Ireland. 相似文献
126.
The Cactaceae contain many economically promising species primarily in the genus Opuntia. This genus appears to have its center of genetic diversity in Mexico where it is widely used as fodder, forage, fruit, and a green vegetable. In southwestern United States, the prickly-pears have been considered as both weeds and valuable forage plants. During the frequent, unpredictable droughts, propane torches known as “pear burners” are used to singe the spines off cactus pads so that they can be eaten by livestock. Although spineless varieties of Opuntia can be consumed directly by domestic livestock, they are extremely susceptible to herbivory by wildlife. The Cactaceae possess Crassulacean Acid Metabolism, which can be four- to five-fold more efficient in converting water to dry matter than the most efficient grasses. Some Opuntia strains grow rapidly with fresh-fruit yields of 8,000–12,000 kg/ha/ yr or more and dry-matter vegetative production of 20,000–50,000 kg/ha/yr. 相似文献
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Expression vectors for cDNA of the κ and λ1 chains of a monoclonal antibody directed against creatine kinase were introduced into murine myeloma cells. κ and γ1 cDNA were either under the control of the SV40 early promoter or of the cognate promoters and enhancers of the light- and heavy-chain genes. Secretion of immuno-reactive κ and γ1 chains into the culture medium was demonstrated with the SV40 promoter as well as with the cognate promoters. Expression of y 1 cDNA with the SV40 early promoter was about twice as high as with the heavy-chain promoter and enhancer. Expression of κ cDNA under the control of the S V40 early promoter was about 17 times higher than with the light-chain promoter and enhancer. These expression levels were compared to those of a genomic immunoglobulin (Ig) κ determinant, including introns. Such an entire κ gene led to expression of the light chain at levels double those with the κ cDNA construction using the SV40 promoter and about 35 times as high when using κ cDNA and the cognate promoter and enhancer. This result might indicate that, besides the cognate promoter and enhancer elements, other intragenic elements are involved in the regulation of Ig expression. However, the SV40 early promoter seems to be able to compensate for the absence of these postulated regulatory elements probably located in the introns. 相似文献
129.