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31.
The species composition of the damselfly assemblage and the life history patterns of two Coenagrionidae (Ischnura elegans
and Cercion lindeni) were investigated along the urban tract of a river characterized by increasing organic pollution. The
assemblage was dominated by generalist species, usually recorded in lentic habitats, rather than by typical riverine species
and the proportion of the latter decrease at the most polluted sites. At the end of Winter, the mean size and in star distribution
were different between the sampling sites showing that the life history of both species examined were influenced by a degradation
of the environmental quality. A longer reproductive period, absence of diapause, and tolerance of low oxygen concentration
appear to be key factors that allow generalist species I. elegans and C. lindeni to predominate at the polluted sites.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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Allen J. St. Angelo Robert L. Ory Falk R. Rittig 《Journal of Plant Growth Regulation》1984,3(1-4):183-187
Peanut,Arachis hypogaea, plants were treated in the field with the bioregulator BAS 105 00W, 4-chloro-5-dimethylamino-2-phenylpyridazin-3-one, a substituted pyridazinone, at different times of development. The seeds were harvested, dried, hand-shelled, and analyzed for lipoxygenase activity and conjugated diene hydroperoxide content. Reduced lipoxygenase activity occurred when the bioregulator was applied to the plants at flowering and pegging. The conjugated diene hydroperoxide content decreased the most in peanuts when the bioregulator was applied at pegging. The apparent Km for lipoxygenase of treated peanuts with linoleic acid as substrate was the same as that for untreated peanuts. 相似文献
35.
A Casino M Cipollaro A M Guerrini G Mastrocinque A Spena V Scarlato 《Nucleic acids research》1981,9(6):1499-1518
A Fortran computer algorithm has been used to analyze the nucleotide sequence of several structural genes. The analysis performed on both coding and complementary DNA strands shows that whereas open reading frames shorter than 100 codons are randomly distributed on both DNA strands, open reading frames longer than 100 codons ("virtual genes") are significantly more frequent on the complementary DNA strand than on the coding one. These "virtual genes" were further investigated by looking at intron sequences, splicing points, signal sequences and by analyzing gene mutations. On the basis of this analysis coding and complementary DNA strands of several eukaryotic structural genes cannot be distinguished. In particular we suggest that the complementary DNA strand of the human epsilon-globin gene might indeed code for a protein. 相似文献
36.
Robert P. Casey Clemens Broger Marcus Thelen Angelo Azzi 《Journal of bioenergetics and biomembranes》1981,13(5-6):219-228
We report here studies which characterize further the interaction ofN,N-dicyclohexylcarbodiimide with cytochromec oxidase leading to inhibition of H+ translocation by the enzyme. Further evidence is presented to show that the inhibition results from a real interaction of DCCD with the enzyme and cannot be accounted for by uncoupling and, contrary to recent criticisms, this interaction occurs specifically with subunit III of the enzyme even at relatively high inhibitor-to-enzyme stoichiometries. Use of a spin-label analogue of DCCD has enabled us to demonstrate that the carbodiimide-binding site is highly apolar and may not lie on the pathway of electron transfer.Abbreviations DCCD
N,N-dicyclohexylcarbodiimide
- NCCD
N-(2, 2, 6, 6-tetramethylpiperidyl-1-oxyl)-N-(cyclohexyl)carbodiimide
- Hepes
2-(N-2-hydroxyethylpiperazin-N-yl) ethane sulfonate
- TMPD
N,N,N,N-tetramethylphenylenediamine 相似文献
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Janet Nilsson Valsa Mannickarottu Celina Edelstein Angelo M. Scanu 《Analytical biochemistry》1981,110(2):342-348
Starting from a single-spin ultracentrifugation procedure described previously (Foreman et al., J. Lipid Res. 18, 759, 1977), we have improved the system for detection of the fractions eluted from the gradient by monitoring them continuously at 280 nm. A graphic display readily permits assessment of the distribution of the lipoproteins and their quantification with the aid of a computer program. By the use of appropriate factors, one can convert absorbance readings into actual lipoprotein values which correspond well (±7% for low-density lipoproteins and ±5% for high-density lipoproteins) to those obtained by means of chemical analyses. The examples provided indicate the versatility of the method and its sensitivity (down to 0.1 ml of serum). 相似文献