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排序方式: 共有357条查询结果,搜索用时 15 毫秒
1.
Cordonnier Marion Gibert Corentin Bellec Arnaud Kaufmann Bernard Escarguel Gilles 《Landscape Ecology》2019,34(8):1937-1948
Landscape Ecology - Urbanization is a global change which deeply impacts landscapes. Long studied through transects along urbanization gradients, ecological response to urbanization can now be... 相似文献
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Mark D. Rawling Nicola Pontefract Ana Rodiles Ilektra Anagnostara Eric Leclercq Marion Schiavone Mathieu Castex Daniel L. Merrifield 《Journal of the World Aquaculture Society》2019,50(6):1108-1122
Fish were fed a single‐strain yeast fraction (SsYF; 2 g/kg) or a multistrain yeast fraction (MsYF; 0.8 g/kg) for 10 weeks. The results demonstrated significant (p ≤ 0.03) elevations in weight gain, specific growth rate, protein efficiency ratio, and feed conversion ratio in fish fed the yeast fraction‐supplemented diets. In the distal intestine, a significant elevation in microvilli density was observed after 5 and 10 weeks of dietary supplementation with MsYF and SsYF, respectively, compared to control fed fish (p < 0.001). A significant elevation (p = 0.02) in the perimeter ratio was observed in fish fed diets supplemented with the yeast fractions. After 10 weeks of feeding on the experimental diets, Rt‐qPCR demonstrated a significant downregulation (p < 0.05) in the stress response genes, heat‐shock protein 70 (hsp70) and proliferating cell nuclear antigen (pcna), in fish fed diets supplemented with the yeast fractions. Significant (p < 0.05) elevations in interleukin 1‐beta (il1β) and interleukin‐10 (il10) gene expression were observed in fish fed diets supplemented with the MsYF compared to the other dietary groups. These findings suggest that feeding an MsYF specifically at a lower incorporation rate < 1 g/kg, compared to a commercial SsYF at 2 g/kg, is effective in improving the intestinal health status and growth performance of European seabass. 相似文献
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Alexis Duhamelle Isabelle Langlois Marion Desmarchelier 《The Canadian veterinary journal. La revue veterinaire canadienne》2015,56(7):737-740
A 3.5-year-old spayed female ferret, fed a diet high in refined sugar, was referred for lethargy, polyuria, polydipsia, and polyphagia. Diabetic ketoacidosis was diagnosed. Treatment included insulin therapy and a low carbohydrate diet. Diabetes mellitus resolved 54 d later, and insulin therapy was discontinued. There has been no recurrence of the diabetes mellitus. 相似文献
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Molecular mapping of powdery mildew resistance genes in wheat: A review 总被引:40,自引:3,他引:40
Powdery mildew, caused by Blumeria graminis f. sp. tritici (syn. Erysiphe graminis f. sp. tritici), is one of the most important diseases of common wheat (Triticum aestivum L.) worldwide. Molecular mapping and cloning of genes for resistance to powdery mildew in hexaploid wheat will facilitate the study of molecular mechanisms underlying resistance to powdery mildew diseases and help understand the structure and function of powdery mildew resistance genes, and permit marker-assisted selection in breeding programs. So far, 48 genes/alleles for resistance to powdery mildew at 32 loci have been identified and located on 16 different chromosomes, of which 21 resistance genes/alleles have been tagged by restriction fragment length polymorphisms (RFLPs), random-amplified polymorphic DNAs (RAPDs), amplified fragment length polymorphisms (AFLPs), sequence characterized amplified regions (SCARs), sequence-tagged sites (STS) or simple sequence repeats (SSRs). Several quantitative trait loci (QTLs) for adult plant resistance (APR) to powdery mildew have been associated with molecular markers. The detailed information on chromosomal location and molecular mapping of these genes has been reviewed. Isolation of powdery mildew resistance genes and development of valid molecular markers for pyramiding resistance genes in breeding programs is also discussed. 相似文献
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Cell wall degradation is a crucial process within the malting process of barley. Therefore, the haplotype diversity of genes for two cell wall degrading enzymes, (1 → 3),(1 → 4)-β-d-Glucan-4-glucanohydrolase and (1 → 4)-β-Xylan-endohydrolase 1, was investigated and associations to malting quality parameters were performed. The (1 → 3),(1 → 4)-β-d-Glucan-4-glucanohydrolase gene glb2 had two major haplotypes defined by three SNPs and one INDEL, which explained 8.9 and 9.5% of the total variation of malt extract content and viscosity in the spring barley gene pool, respectively. The most significant associations of (1 → 4)-β-Xylan-endohydrolase 1 gene X-1 were found for diastatic power, saccharification VZ45 and soluble nitrogen with 18, 12 and 8% of the total variation explained by SNP3 in the spring barleys. High-throughput markers were developed for both genes which can be used for marker assisted selection. 相似文献
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不同施肥条件下夏玉米的干物质积累、产量及氮肥利用效率 总被引:24,自引:2,他引:24
针对我国华北地区夏玉米生产中所面临的氮素污染和秸秆资源严重浪费等问题,中国农业大学和德国霍恩海姆大学(Hohenheim University of Germany)自1999以来开展了中德国际合作项目“华北平原作物高产高生产力条件下环境可承受的持续农业研究”。研究表明:在同一时期,优化施肥、秸秆还田优化施肥与传统施肥夏玉米干物质积累量无显著性差异。拔节到吐丝,优化施肥的干物质日增长量和干物质积累量并不低于传统施肥,吐丝到灌浆,略低于传统施肥;秸秆还田优化施肥两阶段的干物质日增长量和干物质积累量最高。3处理间夏玉米产量无显著性差异。优化施肥和秸秆还田优化施肥条件下,氮肥当季利用率显著高于传统施肥。 相似文献