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1.
The methanol, petroleum ether, ethyl acetate and water-methanol extracts of Ruta graveolens were found to possess antimicrobial and cytotoxic activities.  相似文献   
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The results of study of spontaneous fruit size and shape mutants and inheritance of these traits in tomato are given and genetic processes are explained. It is concluded that the diversity of tomato fruit shape and weight in the collection is due mainly to mutations of genes—diameter of fruit width and diameter of height joined into an ovate cluster.  相似文献   
4.
Induced parthenogenesis as a possible method of haploidization in sunflower (H. annuus L.) was tested in previous investigations (Todorova et al., 1994) and conditions for reproducible regeneration of gynogenic doubled haploids were established by the present work. Forty eight treatments were studied, involving four pollen donors and four recipient hybrids. Pollen was irradiated with doses of 300 Gy, 600 Gy and 900 Gy. In total, 2279 embryos were cultivated in vitro of which 1107 plants were obtained and 582 of them produced seeds after selfing. The ploidy level of the regenerants was evaluated at the two – three leaf stage and 296 of the plantlets obtained were haploids. Some of them underwent spontaneous diploidization, the others were treated with colchicine solution for chromosome doubling. The diploid plantlets were checked for their gynogenic origin by genetical and biochemical methods. The effectiveness of the method expressed as the number of agronomically useful DH lines to the number obtained that were fertile and resistant to downy mildew, branched and unbranched plants was 8,6% on average. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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The occurrence of the two new cis-fused A/B rings furostanol saponins (25S)-26-O-β-d-glucopyranosyl-5β-furostan-1β,3β,22α,26-tetraol-1-O-β-d-glucopyranoside and (25S)-26-O-β-d-glucopyranosyl-5β-furostan-1β,2β,3β,5β,22α,26-hexaol and the known compounds (25S)-26-O-β-d-glucopyranosyl-5β-furostan-3β,22α,26-triol-3-O-α-l-rhamnopyranosyl-(1→2)-O-β-d-glucopyranosyl-(1→2)-O-β-d-glucopyranoside and (25S)-26-O-β-d-glucopyranosyl-5β-furostan-3β,22α,26-triol-3-O-β-d-glucopyranosyl-(1→2)-O-β-d-glucopyranoside, trans-resveratrol, (+) catechin and (−) epicatechin in the rhizomes of Smilax aspera is reported. All saponins have been isolated as their 22-OMe derivatives, which were further subjected to extensive spectroscopic analysis. The isolated furostanol saponins were evaluated for cytotoxic activity against human normal amniotic and human lung carcinoma cell lines using neutral red and MTT assays. In vitro experiments showed significant cytotoxicity in a dose dependent manner with IC50 values in the range of 32.98-94.53 µM.  相似文献   
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Nucleotide sequence of a section of the Env 105 gene of bovine leukemia provirus isolates, obtained from farm animals in different regions of Russia, was determined. Conducted phylogenetic analysis has allowed us to assess heterogeneity of the studied population of the bovine leukemia virus (BLV). Based on results of BLV genetic diversity, four virus’s genotypes—I, II, IV, and VII with dominating genotype IV—were detected.  相似文献   
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Factors influencing the rooting-potential of stem cuttings of conifers were studied for the purpose of improving methods of rapid vegetative propagation. Within the bounds of hereditary limits, root regeneration depends, to a considerable extent, on the qualities of rooting-media, date of cutting excision, age and physiological conditions of the stock plant, age of the cutting-wood, its position on the plant, and chemical treatment. Hardwood cuttings, which have a relatively high content of endogenous auxin and carbohydrates, and morphological root initials, gave the best results. This method made it possible to increase the growth rate of cuttings 2.5–5 times that of cuttings taken from shoots of current growth.  相似文献   
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It is established that metabolism of nitric oxide (NO) in the chicken embryo and posthatch growth rate of chicks have a direct relation which is determined both by the genotype and by external factors influencing posthatch growth rate.  相似文献   
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Bacterial diversity in peat bogs of the karst origin was studied with the use of traditional inoculation methods and modern molecular techniques. Representatives of phylogenetic groups of Proteobacteria and Acidibacteria predominated among the domain of Bacteria. Aquaspirillum and Bacillus predominated in the saprotrophic bacterial complex. The amount of actinobacteria in the studied peat samples was higher than that in typical oligotrophic peat bogs.  相似文献   
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