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The aim of the work was to investigate antitumoral effect of essential oils on cancer cells and their possible protective (antioxidant) effects against hydrogen peroxide-induced cytotoxicity. Also, in vitro antioxidant properties of essential oils and aqueous extracts from wild form and cultivated form of Salvia pisidica were compared.  相似文献   
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The present work proposes the use of Pleurotus ostreatus immobilized on Amberlite XAD-4 as new biosorbent in trace metal determination. The effects of experimental parameters, such as “pH and flow rate of sample solution, amount of solid phase, eluent type, and concentration” on the recovery of the metal ions were investigated. Maximum adsorption of Cr(III), Cd(II) and Cu(II) ions took place in the pH range 4-5. These metal ions can be desorbed with 1 M HCl (recovery 95-100%). 0.2 g adsorbent amount and 2.5 mL min−1 flow rate was found to be optimum of all preconcentration experiments. The sorption capacity after 10 cycles of sorption and desorption does not vary more than 2.0%. The influences of the contaminant ions on the retentions of the analytes were also examined. The results showed that P. ostreatus immobilized on Amberlite XAD-4 can be considered as very promising material in trace metal determination.  相似文献   
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Recent evidence shows that plant polyphenols exhibit antioxidant and radical scavenging properties. By three separate and complementary methods--DPPH assay, beta-carotene-linoleic acid assay and NBT-reduction assay it was established that a polyphenol-rich extract from the medicinal plant Geranium sanguineum L. with strong anti-influenza virus activity, possessed antioxidant and radical scavenging capacities. For comparative reasons caffeic acid and the synthetic antioxidant BHT were used. Total soluble phenolic constituents of the MeOH extract measured by Folin-Ciocalteu reagent were found as 34.60% (w/w). Further it was demonstrated that the EtOAc fraction, retaining the majority of the in vivo protective effect exhibited a strong O2-scavenging activity while the n-BuOH fraction, containing the majority of the in vitro antiviral activity provoked generation of O2-. The O2- scavenging activity of all three preparations correlated with the rate of the protective effect shown in the murine model of experimental influenza virus infection. The present results are in accordance with our intensive studies on the mode of the protective effect of the plant extract which showed positively that the protection may possibly be attributed to the combination of more than one biological activities and that the use of antioxidants might be an useful approach in the treatment of influenza infection.  相似文献   
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International Journal of Peptide Research and Therapeutics -  相似文献   
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Pollen morphology of 38 Trigonella species was investigated with light microscopies and scanning electron microscopies. Pollen slides were prepared using Wodehouse technique. The pollen grains of Trigonella members are radially symmetrical and isopolar, their outlines are oblong in equatorial view and circular in polar view. Amb is semicircular. The pollen grains are prolate-spheroidal, oblate-spheroidal, suboblate, spheroidal, and prolate with the polar axes 13.5–49.9 μm and the equatorial axes 10.4–43.7 μm. The smallest dimensions are observed in T. spinosa and T. brachycarpa, and the largest in T. carica and T. rhytidocarpa. The pollen grains of Trigonella taxa are usually tricolporate or rarely tricolpate, pantocolporate, tetracolporate, and tricolpodiporate. Various ornamentation types were observed: Microreticulate (section Samaroideae, Pectinatae, Falcatulae, Cylindricae, Bucerates, Reflexae, Isthmocarpae, Capitatae and Foenum-graecum), rugulate-scabrate (section Lunatae, Uncinatae), perforate (T. halophila, T. rigida and T. carica from section Bucerates) and retipilatae (section Biebersteinianae) at equator region and psilate-perforate (section Samaroideae, Pectinatae, Bucerates, Reflexae, Isthmocarpae, Foenum-graecum, T. coelesyriaca, T. cilicica), rugulate-scabrate (section Lunatae, Uncinatae), microreticulate (Falcatulae, Cylindricae and Foenum-graecum) and retipilatae (section Biebersteinianae) at polar region. Ornamentations, pollen shape and the aperture type have been observed as important morphological characters.  相似文献   
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Expression of the mouse miR-290–295 cluster and its miR-371–373 homolog in human is restricted to early embryos, primordial germ cells, the germ line stem cell compartment of the adult testis and to stem cell lines derived from the early embryonic lineages. Sequencing data suggest considerable seed diversification between the seven homologous pre-miRNAs of miR-290–295 but it is not clear if all of the implied miR-290–295 seeds are also conserved in the human miR-371–373 cluster, which consists of only three homologous pre-miRNAs. By employing miRNA target reporters we show that most, if not all, seeds in miR-290–295 are represented in miR-371–373. In the mouse, pre-miR-290, pre-miR-292 and pre-miR-293 express subsets of the miRNA isoforms processed from the single human pre-miR-371. Comparison of the possible miR-290–295/miR-371–373 seed repertoires in placental mammals suggests a model for the evolution of this miRNA cluster family, which would be otherwise difficult to deduce based solely on pre-miRNA sequence comparisons. The conservation of co-expressed seeds that is characteristic of miR-290–295/miR-371–373 should be taken into account in models of the corresponding miRNA-target interaction networks.  相似文献   
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This study concerns the evaluation of micromorphological and anatomical characters of fruit (achene-cypsela) in 12 Turkish endemic Tripleurospermum taxa using multivariate analyses (cluster analysis, principal component analysis, one-way analysis of variance). Pericarp in all taxa examined is mainly composed of several layers of parenchymatous and sclerenchymatous cells with one vascular bundle in each rib. In the achene, the thickness and width of lateral and adaxial ribs with presence or absence of a slime envelope have high taxonomic value for Tripleurospermum at interspecific levels. The slime envelope formation is also correlated with ploidy levels and habitats of some taxa in Tripleurospermum.  相似文献   
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