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1.
In this paper the recent population changes of the Wild Boar in different European countries is analysed through the study of hunting statistics. A simultaneous increase in numbers is observed throughout the whole area during the period 1965–1975. From 1975 onwards the population stabilizes itself apart from in peripheral areas like Finland. Potentially favourable factors which play a part in this process are discussed and certain reproductive and dispersive characteristics which favour its invasive behaviour are discussed. 相似文献
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R F Harvey M B Schullinger A Stassinopoulos E Winkle 《BMJ (Clinical research ed.)》1983,287(6409):1916-1919
During a series of presentations of scientific papers 40.6% of 276 subjects reported dreaming, but only 18.1% actually fell asleep. The frequency of dreaming was significantly increased by the addition of either "very boring" or "very interesting" slides to the usual ones, but not by "neutral" slides. The recall of lecture content and the proportion of audience asleep were (surprisingly) not greatly affected by the addition of extraneous slides of any sort. On the other hand, adding "very interesting" slides greatly increases audience enjoyment. 相似文献
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A novel protein-RNA binding assay: functional interactions of the foot-and-mouth disease virus internal ribosome entry site with cellular proteins 总被引:3,自引:0,他引:3
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Translation initiation on foot-and-mouth disease virus (FMDV) RNA occurs by a cap-independent mechanism directed by a highly structured element (approximately 435 nt) termed an internal ribosome entry site (IRES). A functional assay to identify proteins that bind to the FMDV IRES and are necessary for FMDV IRES-mediated translation initiation has been developed. In vitro-transcribed polyadenylated RNAs corresponding to the whole or part of the FMDV IRES were immobilized on oligo-dT Dynabeads and used to deplete rabbit reticulocyte lysate (RRL) of IRES-binding proteins. Translation initiation factors eIF4G, eIF4A, and eIF4B bound to the 3' domain of the FMDV IRES. Depletion of eIF4G from RRL by this region of the FMDV IRES correlated with the loss of translational capacity of the RRL for capped, uncapped, and FMDV IRES-dependent mRNAs. However, this depleted RRL still supported hepatitis C virus IRES-directed translation. Poly (rC) binding protein-2 bound to the central domain of the FMDV IRES, but depletion of RRL with this IRES domain had no effect on FMDV IRES-directed translation initiation. 相似文献
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TANATIN BI 《Mikrobiologiia》1951,20(6):506-511
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ANDRÉIA SILVA FLORES RÉA M. CORRÊA ELIANA R. FORNI-MARTINS ANA M. G. AZEVEDO TOZZI 《Botanical journal of the Linnean Society. Linnean Society of London》2006,151(2):271-277
Chromosome numbers were counted for 23 species of Crotalaria native to Brazil. Among these data there were new counts for 15 taxa, and some confirmed previous reports or represented numbers that were different from those cited previously. The chromosome numbers most frequently found were 2 n = 16 and 2 n = 32. Only C. incana L. had 2 n = 14 and C. tweediana Benth. had 2 n = 54. The counts 2 n = 32 and 54 were found in species of section Calycinae and 2 n = 16 and 14 in species of section Chrysocalycinae . The data revealed the importance of chromosomal parameters in the characterization of sections Calycinae and Chrysocalycinae in Brazil. We discuss the systematic significance and evolutionary aspects for the genus, comparing the results with the two sections that are native in Brazil. © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 271–277. 相似文献
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Ricci GC De Souza-Kaneshima AM Felismino MF Mendes-Bonato AB Pagliarini MS Do Valle CB 《Journal of genetics》2011,90(2):289-294
A total of 44 accessions of Brachiaria decumbens were analysed for chromosome count and meiotic behaviour in order to identify potential progenitors for crosses. Among them,
15 accessions presented 2n = 18; 27 accessions, 2n = 36; and 2 accessions, 2n = 45 chromosomes. Among the diploid accessions, the rate of meiotic abnormalities was low, ranging from 0.82% to 7.93%. In
the 27 tetraploid accessions, the rate of meiotic abnormalities ranged from 18.41% to 65.83%. The most common meiotic abnormalities
were related to irregular chromosome segregation, but chromosome stickiness and abnormal cytokinesis were observed in low
frequency. All abnormalities can compromise pollen viability by generating unbalanced gametes. Based on the chromosome number
and meiotic stability, the present study indicates the apomictic tetraploid accessions that can act as male genitor to produce
interspecific hybrids with B. ruziziensis or intraspecific hybrids with recently artificially tetraploidized accessions. 相似文献
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The genetic variability at six cloned minisatellite loci was analyzed in
minke whale populations from the North Atlantic, North Pacific, and
Antarctic Oceans. Three loci displayed only a few different alleles in each
of the three populations, with heterozygosity ranging from 0.00 to 0.47,
and three loci revealed many different alleles in at least two fo the three
populations, with heterozygosity ranging up to 0.98. Using small sample
sizes, samples from two adjacent Antarctic Management Areas were not found
to differ significantly in allele frequencies at any of the six loci. The
use of principal coordinate analysis to detect multilocus disequilibria was
explored. No significant evidence was found of intrapopulation
heterogeneity within the pooled Antarctic sample. Pronounced interoceanic
differences were observed at every locus, confirming the existence of
genetic isolation found earlier using more conventional marker systems. The
populations from the three oceans appear to have diverged to such a degree
that the hypervariable loci have had time to evolve independently and
arrive at different evolutionary stages in different populations. The
frequency of undetected "null" alleles is remarkably high in minke whale
populations compared to human populations and is probably a result of the
cloning protocol used. Minisatellite loci are shown to provide a powerful
population genetic tool, supplying levels of resolution appropriate to
different degrees of evolutionary divergence.
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M Leach E Cameron N Fite J Stassinopoulos N Palmreuter J D Beckmann 《Biochemical and biophysical research communications》1999,261(3):815-819
Phenol sulfotransferases (PSTs, EC 2.8.2.1) catalyze sulfonyl group transfer from 3'-phosphoadenosine-5'-phosphosulfate (PAPS) to the hydroxyl oxygen of aromatic acceptor substrates. The structural overlap between PAPS and coenzyme A (CoA) suggested a possible role of this common acyl carrier in modulating PST activity. To test this hypothesis, purified recombinant bovine PST was examined by kinetic and affinity chromatographic approaches. After demonstrating PST enzyme inhibition by CoA, systematic variation of CoA and PAPS concentrations indicated simple competitive inhibition with K(i) = 1. 3 microM. PST bound to CoA-agarose, attached via the pantetheinyl thiol group, was eluted with PAP but not by 2-naphthol. This observation was consistent with the pattern of inhibition. Additional members of the sulfotransferase superfamily, as well as acylated CoAs, should be further investigated. 相似文献