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Antygen D z układu Rh jest najsilniejszym immunogenem wszystkich znanych antygenów krwinek czerwonych. Dlatego też należy go oznaczać zarówno u dawców jak i biorców krwi. Dawcy fenotypowani nie są łatwo dostępni, ale konieczni w procesie identyfikacji przeciwciał. Szczególnie ważne są homozygoty DCCee i DccEE. Badania serologiczne umożliwiają wydzielenie homozygotycznych krwiodawców układzie Rh. Celem pracy było określenie częstości występowania dwóch homozygotycznych fenotypów z układu Rh: DCCee i DccEE krwiodawców Rh dodatnich Regionalnego Centrum Krwiodawstwa i Krwiolecznictwa w Warszawie. Częstość występowania analizowanych u krwiodawców fenotypów jest zróżnicowana. Homozygotyczny fenotyp DCCee występuje częściej (92%) niż fenotyp DccEE (8%). Częstość występowania homozygotycznych fenotypów układu Rh w grupach krwi układu AB0 jest na granicy istotności.
The effect of methyl jasmonate (MJ) vapors on content of phenolic compounds: free phenolic acids, total quercetin, and total phenolics in etiolated buckwheat seedlings were studied. The data presented show that low concentration of MJ (10-8 M) had no influence on trans-cinnamic acid (CA), but stimulated the accumulation of chlorogenic acid in hypocotyls and cotyledons of buckwheat seedlings. A moderate dose of MJ (10-6 M) did not change the level of chlorogenic acid in the hypocotyls and cotyledons, but CA synthesis was promoted in cotyledons, whereas in hypocotyls no significant effect was found. Highest concentration of MJ (10-4 M) caused small decline of CA in hypocotyls, but large stimulation of the acid production in cotyledons was noted. MJ had stimulatory effect on caffeic acid forming, but inhibited synthesis of vanillic acid in hypocotyls and cotyledons. Lowest concentration of MJ (10-8 M) elicited accumulation of quercetin glycosides in both studied tissues of buckwheat seedlings, however at higher doses (10-6 and 10-4 M) did not affect the flavonol level. The obtained results suggest that nonequivalent influence of methyl jasmonate on the phenolics composition can be a result of various mechanisms of MJ uptake, transforming and/or its translocation in buckwheat hypocotyls and cotyledons. Decline of anthocyanins level in buckwheat hypocotyls caused by MJ cannot be explained by enhanced accumulation of quercetin glycosides or free phenolic acids, but probably by synthesis of other unknown phenolic compounds.
The effects of exogenously applied methyl jasmonate on content of biogenic amines: putrescine, spermidine, tyramine, cadaverine and 2-phenylethylamine in seedlings of common buckwheat (Fagopyrum esculentum Moench) were investigated. The studies have shown that methyl jasmonate stimulates the conversion of L-phenylalanine into 2-phenylethylamine and increases the endogenous levels of putrescine in hypocotyls and cotyledons of buckwheat seedlings. Simultaneous feeding the seedlings with L-phenylalanine and methyl jasmonate has indicated that conversion of L-phenylalanine into 2-phenylethylamine can be one of possible reasons, caused by the methyl jasmonate suppression of anthocyanins synthesis in hypocotyls. To our knowledge, the stimulation of conversion of L-phenylalanine into 2-phenylethylamine by methyl jasmonate, as found in the present study, is described for the first time in higher plants.
We tested 24 microsatellite markers for the red-breasted flycatcher, Ficedula parva, using the primers for the PCR reaction described for other species from genus Ficedula. The amplification efficiency, specificity of the products, and polymorphism of cross-amplified microsatellites were determined based on the genotypes of 65 adult males from a natural population breeding in Białowieża Forest (Eastern Poland). Based on obtained results, we identified 9 highly polymorphic microsatellites, consistently amplifying in majority of individuals. Among those markers between 4 and 26 alleles per locus (mean 15.4) were found and the observed heterozygosity ranged from 0.393 to 0.939. The majority of loci (except for Fhy350 and Fhy458) were in Hardy-Weinberg equilibrium. Accordingly, the values of F IS did not significantly differ from zero 0, except for the locus Fhy350. We suggest that this locus could be loaded with high frequency of null alleles. The polymorphic information content (PIC) for the selected loci set was high and in all cases exceeded 0.82. In addition, we calculated, for each locus, the probability of excluding an improper parent. In majority of loci this parameter distinctly exceeded 0.5. These results demonstrate that tested microsatellite markers can be used to estimate the genetic variability within- and between populations and to establish paternity and parenthood in red-breasted flycatcher populations.
The aim of the study was to assess the impact of auxin (IAA), gibberellin (GA3) and cytokinin (kinetin), used solely and in combination with methyl jasmonate (MJ), on the accumulation of anthocyanins and biogenic amines in hypocotyls and cotyledons of common buckwheat (Fagopyrum esculentum Moench) seedlings. The obtained results indicate that accumulation of anthocyanins in buckwheat seedlings was dependent on the concentration of the phytohormone applied and the tissue studied. The combined use of MJ and IAA, GA3 or kinetin partly reversed the effect of strong inhibition of anthocyanin synthesis by MJ. IAA used solely decreased the level of anthocyanins in de-etiolated buckwheat cotyledons. IAA also caused a reduction of putrescine content, both in hypocotyls and cotyledons of buckwheat seedlings. MJ used alone caused high accumulation of 2-phenylethylamine (PEA) in buckwheat cotyledons and hypocotyls. The simultaneous application of MJ and IAA, GA3 or kinetin also stimulated PEA synthesis in buckwheat tissues, however this effect was significantly lower compared to the use of MJ only. A reverse significant correlation between PEA and anthocyanin contents occurred in buckwheat hypocotyls, but not in cotyledons. It was suggested that the deficiency of L-phenylalanine, a substrate for synthesis of 2-phenylethylamine, may be partly responsible for the decline in anthocyanin content in buckwheat hypocotyls under the influence of MJ.
The aim of this study was to compare the tolerance of seedlings of three Polish buckwheat cultivars (Hruszowska, Kora, and Luba) for short-term exposure to Pb²⁺ and Cd²⁺. Seedlings were grown under controlled conditions in Hoagland nutrient solution, with the addition of low/high Pb²⁺ or Cd²⁺ ions (0.01 and 1.00 mM, respectively). After 3 days of treated seedling growth, the levels of total anthocyanins and content of particular flavonoids were measured. The presence of low concentrations of both Pb²⁺ and Cd²⁺ resulted in a small stimulation of the growth of seedlings of all studied cultivars, while higher doses inhibit root growth and, to a much lesser extent, that of shoots. Cadmium (Cd²⁺) ions were more harmful for growth of buckwheat seedlings than Pb²⁺ ions. More resistant to stress caused by the presence of high concentrations of Pb²⁺ and Cd²⁺ in the growth medium were seedlings of Hruszowska and Luba cultivars, compared to Kora seedlings. Cotyledons of more resistant cultivars (Hruszowska and Luba) contained much more flavonoids than cotyledons of Kora.
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