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C. Pinho F. Sequeira R. Godinho D. J. Harris N. Ferrand 《Molecular ecology resources》2004,4(2):286-288
Nine dinucleotide microsatellite loci were developed through an enrichment protocol for Bocage's wall lizard, Podarcis bocagei Seoane 1884, a lacertid endemic to the Iberian Peninsula. Nineteen primer pairs were designed and tested. From these, nine loci yielded satisfactory results and were screened on 15–19 individuals. These loci revealed a high level of polymorphism (8–15 alleles) and heterozygosity (0.611–0.947) and will certainly be useful in the study of population structure and evolutionary history of this species. 相似文献
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The propensity of highly purified proteolipids to form macroaggregates in aqueous solutions, especially when heated with sodium dodecyl sulfate (SDS), with or without thiol reagents, has made qualitative and quantitative analyses of individual species by SDS-polyacrylamide gel electrophoresis (SDS-PAGE) difficult and unreliable. Comparisons of proteolipid profiles from liver, brain, and cultured human keratinocytes demonstrate that 40-72% of the total proteolipid in SDS-PAGE sample buffer is in the form of macroaggregates. Treatment of proteolipids with neat trifluoroacetic acid (TFA) followed by removal of the TFA and incubation in cold SDS-PAGE sample buffer causes complete dispersal of the macroaggregates and allows recovery of virtually all of the proteolipid applied to gels (increasing yields by as much as 3.6 times, depending on tissue type). Gels of TFA-treated samples display differences not only in the relative amounts of individual species but also in novel species not found in untreated samples. Eluted macroaggregates treated with TFA display the same SDS-PAGE banding profiles as TFA-treated whole proteolipids. Hence, routine TFA treatment of proteolipids prior to SDS-PAGE increases total proteolipid yields, allows reliable quantitation of individual apoprotein species, and reveals species previously obscured by the formation of macroaggregates. 相似文献
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Attempts were made to determine whether Marasmius perniciosus Stahel., causal agent of the witches' broom disease of cacao, produces substances that could elicit on the host some of the symptoms which are characteristic of the disease. In vitro the fungos did not produce significant amounts of cytokinins or auxins. However, culture filtrates destroyed indole-3-acetic acid (IAA) rapidly because of two different IAA-oxidizing enzymes: (1) a peroxidase (IAA oxidase) characterized by (a) dependence on Mn++ and 2,4-dichlorophenol (DCP), (b) pH. optimum of 3.0, (c) inactivation at 85 C for 5 min, (d) stimulation of oxidative activity by addition of 0.3 μmole/ml H2O2; and (2) a laccase characterized by (a) no dependence on Mn++ and DCP, (b) pH optimum of 6.0, (c) inactivation at 95 C for 5 min, (d) ability to oxidize IAA and phenolic substrates in the absence of H2O2. The peroxidase was completely inhibited by scopoletin (0.0002 m ) ; the laccase was inhibited by thiourea (0.1 m ). The laccase could be separated from the peroxidase by elution through a column of Sephadex G-100. It is suggested that the main pathogenic effect of the fungus may be associated with these auxin-inactivating systems. 相似文献
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We determined the age-specific fecundity and survival of the solitary parasstoid wasp,Aphidius ervi Haliday (Hymenoptera: Aphidiidae), under constant laboratory conditions. Wasps were reared in each of the four nymphal instars
of apterous pea aphids,Acyrthosiphon pisum (Harris) (Homoptera: Aphididae): L1 (age 24h), L2 (48 h), L3 (72 h), and L4 (120 h). Age-specific survival (lx) and fecundity (mx) differed between parasitoids developing in different aphid instars. The wasps’ life-time reproductive success, as indexed
by the intrinsic rate of population increase (rm), varied non-linearly with adult biomass and host size at parasitization. A close agreement between larval growth rates in
different host instars and adult reproductive performance suggests that, inA. ervi, fitness correlates may be significantly influenced by larval ontogeny and trade-offs in resource allocation. 相似文献
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Ana Neves Vera Sequeira Ana Rita Vieira Rafaela Paiva Leonel Serrano Gordo 《Hydrobiologia》2009,636(1):479-488
The importance of cephalopods in marine ecosystems is well recognized as they serve as important predators and prey in many
food chains. During a 1-year period, cuttlefish were monthly sampled in five areas throughout the Sado estuary, and the stomachs
of 445 individuals were examined. Significant changes in the diet according to their life stage were revealed, but similar
food habits were presented by males and females. Juvenile individuals (the smaller ones with no visible distinct gonads) preyed
mainly upon small crustaceans, while the immature ones (maturity stages I and II) had the most diverse diet with brachyurans
as the major prey group. The mature individuals (maturity stages III and IV) showed a clear preference for larger crabs and
fishes. Although the cuttlefish are known for their opportunistic feeding behaviour, a preference for some prey according
to length and behaviour could be perceived during this study. Seasonal differences in the diet were mostly due to the variation
of individuals according to their maturity stage during the year. 相似文献