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排序方式: 共有1222条查询结果,搜索用时 15 毫秒
991.
992.
Virginie Molinier Claude Murat Martina Peter Armelle Gollotte Herminia De la Varga Barbara Meier Simon Egli Beatrice Belfiori Francesco Paolocci Daniel Wipf 《Mycorrhiza》2016,26(2):99-110
Tuber species are ectomycorrhizal ascomycetes establishing relationships with different host trees and forming hypogeous fruiting bodies known as truffles. Among Tuber species, Tuber aestivum Vittad. has a wide distributional range being found naturally all over Europe. Here, we performed large-scale population genetic analyses in T. aestivum to (i) investigate its genetic diversity at the European scale, (ii) characterize its genetic structure and test for the presence of ecotypes and (iii) shed light into its demographic history. To reach these goals, 230 ascocarps from different populations were genotyped using 15 polymorphic simple sequence repeat markers. We identified 181 multilocus genotypes and four genetic groups which did not show a clear geographical separation; although, one of them was present exclusively in Southeast France, Italy and Spain. Fixation index values between pairs of genetic groups were generally high and ranged from 0.29 to 0.45. A significant deficit of heterozygosity indicated a population expansion instead of a recent population bottleneck, suggesting that T. aestivum is not endangered in Europe, not even in Mediterranean regions. Our study based on a large-scale population genetic analysis suggests that genetically distinct populations and likely ecotypes within T. aestivum are present. In turn, this study paves the way to future investigations aimed at addressing the biological and/or ecological factors that have concurred in shaping the population genetic structure of this species. Present results should also have implications for the truffle market since defining genetic markers are now possible at least for some specific T. aestivum genetic groups. 相似文献
993.
994.
995.
Julie Jerber Maha S. Zaki Jumana Y. Al-Aama Rasim Ozgur Rosti Tawfeg Ben-Omran Esra Dikoglu Jennifer L. Silhavy Caner Caglar Damir Musaev Beate Albrecht Kevin P. Campbell Tobias Willer Mariam Almuriekhi Ahmet Okay Çağlayan Jiri Vajsar Kaya Bilgüvar Gonul Ogur Rami Abou Jamra Murat Günel Joseph G. Gleeson 《American journal of human genetics》2016,99(5):1181-1189
996.
997.
In the present study, the influence of subchronic effects of two plant growth regulators (PGRs) [Abcisic acid (ABA) and Gibberellic acid (GA3)] on antioxidant defense systems [reduced glutathione (GSH), glutathione reductase (GR), superoxide dismutase (SOD), glutathione-S-transferase (GST) and catalase (CAT)] and lipid peroxidation level (malondialdehyde = MDA) in various tissues of the rat were investigated during treatment as a drinking water model. 75 ppm of ABA and GA3 in drinking water were continuously administered orally to rats (Sprague-Dawley albino) ad libitum for 50 days. The PGRs treatments caused different effects on the antioxidant defense systems and MDA content of dosed rats compared to controls. The lipid peroxidation end product MDA significantly increased in the lungs, heart and kidney of rats treated with GA3 without significant change in the spleen. ABA caused also a significant increase in MDA content in the spleen, lungs, heart and kidney. The GSH levels were significantly depleted in the spleen, lungs and stomach of rats treated with ABA without any change in the tissues of rats treated with GA3 except the kidney where it increased. Antioxidant enzyme activities such as SOD significantly increased in the lungs and stomach and decreased in the spleen and heart tissues of rats treated with GA3. Meanwhile, SOD significantly decreased in the spleen, heart and kidney and increased in the lungs of rats treated with ABA. While CAT activity significantly decreased in the lungs of rats treated with GA3, a significant increase occurred in the heart of rats treated with both PGRs. On the other hand, the ancillary enzyme GR activity in the tissues were either significantly depleted or not changed with PGRs treatment. The drug metabolizing enzyme GST activity significantly decreased in the lungs of rats treated with ABA but increased in the stomach of rats treated with both PGRs. As a conclusion, the rats resisted oxidative stress via the antioxidant mechanism. But the antioxidant mechanism could not prevent the increases in lipid peroxidation in rat's tissues. This data, along with changes, suggests that PGRs produced substantial systemic organ toxicity in the spleen, lungs, stomach, heart and kidney during a 50-day period of subchronic exposure. 相似文献
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999.
Among the antimicrobial mechanisms associated with macrophages, NO produced by iNOS plays a major role in intracellular killing, but the relationship between NO and phagocytic activity after injection of inflammatory agents into the peritoneal cavity is not clear. The aim of the present study was to investigate the effect of nitric oxide (NO) on macrophage function after treatment with intraperitoneal lipopolysaccharide (LPS) and the role of exogenous L-arginine administration in this event. Six experimental groups and one control group, each consisting of seven Wistar rats were used: Group I: Control; Group II: LPS; Group III: LPS+L-arginine; Group IV: LPS+L-arginine+Aminoguanidine; Group V: LPS+Aminoguanidine; Group VI: L-arginine; Group VII: Aminoguanidine. Macrophage phagocytic activity and total plasma nitrite levels were increased in the LPS group. In the LPS+L-arginine group, both the phagocytic activity and total plasma nitrite levels showed large increases. Administration of aminoguanidine (AG), a specific iNOS inhibitor, abolished macrophage phagocytic activity and total plasma nitrite levels in the LPS and LPS+L-arginine groups. As a result, we showed that NO produced by macrophages has a role not only in intracellular killing, but also in phagocytic activity. 相似文献
1000.
Genome-scale analysis of in vivo spatiotemporal promoter activity in Caenorhabditis elegans 总被引:2,自引:0,他引:2
Dupuy D Bertin N Hidalgo CA Venkatesan K Tu D Lee D Rosenberg J Svrzikapa N Blanc A Carnec A Carvunis AR Pulak R Shingles J Reece-Hoyes J Hunt-Newbury R Viveiros R Mohler WA Tasan M Roth FP Le Peuch C Hope IA Johnsen R Moerman DG Barabási AL Baillie D Vidal M 《Nature biotechnology》2007,25(6):663-668