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961.
Barbara Lukasch Thomas Frank Christian H. Schulze 《Biodiversity and Conservation》2011,20(6):1339-1352
To study effects of short-term land-use changes on birds in a predominantly agriculturally used landscape in Northeastern
Austria, birds were surveyed in 22 circular study areas with a diameter of 1 km in 2005 and 2009. Because of the abolition
to obligate set-aside land from 2008, it was suspected that the amount of set-aside land would be reduced dramatically. Consequently,
a loss of farmland birds was expected. Results show that the amount of set-aside land indeed decreased significantly between
2005 and 2009 from 15.05% to 9.69% (mean proportion of set-aside land per study area). Farmland birds were represented by
20 species in both years. Neither richness and abundance nor species composition of farmland birds were affected by changes
of set-aside land. The amount of set-aside land in these landscapes was already high (compared to other areas in Austria)
before the amendment of the law and still relatively high after it. Therefore, perhaps changes in the extent of set-aside
land were below the threshold to find detectable effects on farmland birds. 相似文献
962.
H Klug P Schulze 《Virchows Archiv. B, Cell pathology including molecular pathology》1988,56(3):201-203
Electron microscopic investigation of skin biopsies revealed that keratinocytes in clinically uninvolved skin from psoriatic patients show the same mitochondrial ring phenomenon after the application of dithranol as has been observed in the cutaneous lesions proper. In various other skin diseases no mitochondrial reaction was evident after dithranol treatment, nor was it seen in chronic dermatitis when dithranol was not applied. It appears, therefore, that this morphological phenomenon is specific to psoriasis and may provide information concerning functional alterations in the pathogenesis of this disease. 相似文献
963.
Summary A method of accurately estimating and mapping patterns of incoming solar radiation fluxes on sloping terrain, using data from standard meteorological instruments, is described. The results of the radiation maps produced are then related to a specific example of vegetation successional changes in the Cathedral Peak area of the Natal Drakensberg mountain range, indicating that these changes occur most readily on cooler aspects. For the same region, the differences in the major plant communities at two other sites, attributable largely to variations in incoming solar radiation loads, are discussed.The authors wish to thank the Department of Forestry of the Republic of South Africa for providing data and for facilitating fieldwork to be undertaken at Cathedral Peak. This Research was funded in part by the South African Council for Scientific and Industrial Research, whose support is hereby gratefully acknowledged (by R.E.S.). The maps illustrating this paper were prepared by Mrs. C. Coetzee and Mr B. Martin of the University of Natal, Pietermaritzburg. 相似文献
964.
Single and sequential double immunocytochemical techniques were applied to localize gamma-aminobutyric acid (GABA)- and choline acetyltransferase (ChAT)- like immunoreactivity (-LI) in the hypoglossal nucleus of the rat. After subsequential double staining a relatively high number of hypoglossal motor neurons showed the coexistence of both ChAT- and GABA-LI. Coexistence of both substances was also revealed in the axons of the hypoglossal nerve situated within the medulla oblongata. Cells showing only ChAT- or GABA-LI were also observed. Differences in immunostaining between the different cell groups of the hypoglossal nucleus were established. Following axotomy of the right hypoglossal nerve, a decrease or loss of the immunoreactivity for both ChAT and GABA in the motor neurons was established until the 3rd week after the operation. The results obtained do not give evidence on the origin of the GABA-like immunoreactive material and its functional significance in the cholinergic neurons. It can be only speculated that the GABA-like material is either taken up from the intercellular space or is synthesized by the ChAT-LI nerve cells. Functionally, the importance of GABA for the synthesis of gamma-hydroxybutyrate (a novel neurotransmitter candidate) and its postsynaptic transmitter action or presynaptic regulatory action (through autoreceptors in the membrane of the nerve endings) on the release of acetylcholine (ACh) should be taken into consideration. 相似文献
965.
We present a unified approach to the nonparametric comparison of locations in the one- and two sample case using the empirical distribution functions. This approach reveals how to define a simple test statistic for this comparison in the case of large sample sizes which is equivalent to the known Wilcoxon-Mann-Whitney statistics and is based on the grouping of the data. In the particular case of equal group sizes we find an extremely simple form for this location test. 相似文献
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967.
Angelika Bondzio Robert Pieper Christoph Gabler Christoph Weise Petra Schulze Juergen Zentek Ralf Einspanier 《PloS one》2013,8(11)
Pharmacological levels of zinc oxide can promote growth and health of weaning piglets, but the underlying molecular mechanisms are yet not fully understood. The aim of this study was to determine changes in the global hepatic protein expression in response to dietary zinc oxide in weaned piglets. Nine half-sib piglets were allocated to three dietary zinc treatment groups (50, 150, 2500 mg/kg dry matter). After 14 d, pigs were euthanized and liver samples taken. The increase in hepatic zinc concentration following dietary supplementation of zinc was accompanied by up-regulation of metallothionein mRNA and protein expression. Global hepatic protein profiles were obtained by two-dimensional difference gel electrophoresis following matrix-assisted laser desorption ionization/time-of-flight mass spectrometry. A total of 15 proteins were differentially (P<0.05) expressed between groups receiving control (150 mg/kg) or pharmacological levels of zinc (2500 mg/kg) with 7 down- (e.g. arginase1, thiosulfate sulfurtransferase, HSP70) and 8 up-regulated (e.g. apolipoprotein AI, transferrin, C1-tetrahydrofolate synthase) proteins. Additionally, three proteins were differentially expressed with low zinc supply (50 mg/kg Zn) in comparison to the control diet. The identified proteins were mainly associated with functions related to cellular stress, transport, metabolism, and signal transduction. The differential regulation was evaluated at the mRNA level and a subset of three proteins of different functional groups was selected for confirmation by western blotting. The results of this proteomic study suggest that zinc affects important liver functions such as blood protein secretion, protein metabolism, detoxification and redox homeostasis, thus supporting the hypothesis of intermediary effects of pharmacological levels of zinc oxide fed to pigs. 相似文献
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