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The puroindoline genes Pina-D1 and Pinb-D1 located at the Ha locus on chromosome 5D of common wheat are considered the most important genetic determinants of grain hardness. The recent identification of Pinb-2 genes on group 7 chromosomes emphasises the need for detailed analysis of the genetics of this important trait. This study focussed on the analysis of Pinb-2 genes from accessions of hexaploid, tetraploid and diploid wheat, to address key questions related to their diversity and possible roles. Extensive DNA sequence heterogeneity was identified in the form of single nucleotide polymorphisms (SNPs), leading to seventeen reproducible haplotypes, of which thirteen are new. The results confirmed the known groups Pinb-2v1 to Pinb-2v5, identified a new group Pinb-2v6, and showed that the Pinb-2 genes comprised a small multigene family, at least in some genomes. The putative proteins exhibited changes at the important tryptophan-rich domain as well as basic and hydrophobic residues. A new Pina-D1 allele (at Ha locus) was also identified, designated Pina-D1t, with a premature stop codon at the TRD. Additionally, peptides designed on PINB-2 proteins displayed activity against bacteria and phytopathogenic fungi. The data strongly support the Pinb-2 genes being functionally relevant to roles including influencing grain texture.  相似文献   
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Exogenous application of methyl jasmonate (MeJA) can induce anatomical and chemical changes that are components of defence responses in plants. Particularly, MeJA is well‐known to increase leaf trichome density to protect against insect herbivory, but surprisingly little is known about the effects of MeJA on other leaf properties and plant growth. Using sunflower (Helianthus annuus), tomato (Solanum lycopersicum), and soybean (Glycine max) treated with 0.0, 0.1, 0.5, 1.0, and 2.5 mM MeJA, we examined changes in leaf trichome density, stomatal density, cuticle thickness, cuticle composition, plant height, and biomass production. For all three plant species, MeJA (especially at the higher concentrations) caused significant decreases in plant height (up to 39%) and biomass (up to 79%). MeJA caused substantial increases in leaf trichome density (being 1.3–3.5‐times higher) in all three species, with the magnitude of these effects increasing with MeJA concentration. However, we also observed that MeJA resulted in significant changes in cuticle composition and thickness, and stomatal density, although the magnitude of these changes was smaller relative to changes in trichome density. Specifically, high concentrations of MeJA increased the relative content of phenolic compounds and cutin in leaf cuticle while decreasing the relative content of polysaccharide. The changes in stomatal density varied with plant species and MeJA concentration. Also, MeJA increased cuticle thickness in tomato but decreased that in sunflower and soybean. Thus, studies investigating MeJA should also consider the importance of changes in other leaf properties and plant growth.  相似文献   
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Tramadol is a synthetic opioid agonist used extensively in human and, to a lesser extent, veterinary medicine throughout the world. The clinical efficacy and pharmacokinetic profile of intravenous (IV) and extradural (ED) tramadol (2 mg/kg) and its o-desmethyl metabolite were studied in dogs undergoing tibial plateau levelling osteotomy (TPLO). Intra-operative cardiorespiratory variables were monitored and post-operative pain was assessed using the short form of the Glasgow Composite Pain Scale. A rapid (<5 min) and effective production of o-desmethyl tramadol was recorded. The pharmacokinetic profile was similar for tramadol and its metabolite irrespective of the route of administration. ED tramadol provided sufficient intra- and post-operative analgesia without significant clinical side-effects, but the post-operative analgesia was comparable to that following IV administration and the ED route could therefore not be considered a practical alternative to the IV route.  相似文献   
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The effect of red mud (10 g kg–1), a by‐product of the alumina industry, zeolite (20 g kg–1), a naturally‐occurring hydrous aluminosilicate, and lime (3 g kg–1) on metal lability in soil and uptake by fescue (Festuca rubra L.) (FEST) and amaranthus (Amaranthus hybridus L.) (AMA) was investigated in four different soils from Austria. The soil collection locations were Untertiefenbach (UNT), Weyersdorf (WEY), Reisenberg (REI), and Arnoldstein (ARN). The latter was collected in the vicinity of a former Pb‐Zn smelter and was highly polluted with Pb (12300 mg kg–1), Zn (2713 mg kg–1), and Cd (19.7 mg kg–1) by long‐term deposition. The other soils were spiked with Zn (700 mg kg–1), Cu (250 mg kg–1), Ni (100 mg kg–1), V (100 mg kg–1), and Cd (7 mg kg–1) salts in 1987. The two plant species were cultivated for 15 months. Ammonium nitrate (1 M) extraction was used in a soil : solution ratio of 1:2.5 to assess the influence of the amendments on the labile metal pools. The reduction of metal extractability due to red mud was 70 % (Cd), 89 % (Zn), and 74 % (Ni) in the sandy soil (WEY). Plant uptake in this treatment was reduced by 38 to 87 % (Cd), 50 to 81 % (Zn), and 66 to 87 % (Ni) when compared to the control. Sequential extraction revealed relative enrichments of Fe‐oxide‐associated metal fractions at the expense of exchangeable metal fractions. Red mud was the only amendment that decreased lability in soil and plant uptake of Zn, Cd, and Ni consistently. Possible drawbacks of red mud application (e.g., As and Cr concentration) remain to be evaluated.  相似文献   
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Calorie restriction extends life span in organisms ranging from yeast to mammals. Here, we report that calorie restriction for either 3 or 12 months induced endothelial nitric oxide synthase (eNOS) expression and 3',5'-cyclic guanosine monophosphate formation in various tissues of male mice. This was accompanied by mitochondrial biogenesis, with increased oxygen consumption and adenosine triphosphate production, and an enhanced expression of sirtuin 1. These effects were strongly attenuated in eNOS null-mutant mice. Thus, nitric oxide plays a fundamental role in the processes induced by calorie restriction and may be involved in the extension of life span in mammals.  相似文献   
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Canine aggressive behaviour is one of the most common problems being reported by dog owners. However, the biochemical basis of this phenomenon remains unclear. In humans, alterations in omega-3 plasma polyunsatured fatty acids and elevated omega6/omega-3 ratio have been linked to behavioural alterations, including aggression. Thus far, however, the relationship between plasma polyunsatured fatty acid status and aggression has not been investigated in the dog. In the present study we sought to investigate whether polyunsatured fatty acid status could be altered in plasma of pathologically aggressive Canis familiaris. Eighteen adult male German Shepherd dogs, aged 4.9 ± 0.9 years, showing no clinical signs but aggression, were investigated. Eighteen healthy male dogs, aged 4.8 ± 0.7 years, with a negative history of behavioural and neurological disorders served as controls. Baseline fasting plasma polyunsatured fatty acid composition was determined by gas chromatography. Compared to normal dogs, aggressive dogs showed lower docosahexaenoic acid (22:6 n-3) concentrations and a higher omega6/omega-3 ratio. In addition, they showed reduced cholesterol and bilirubin concentrations compared to their normally behaving counterparts. Altogether, our results suggest that low omega-3 fatty acids may adversely impact behaviour in dogs, resulting in greater propensity to aggression. However, given the cross-sectional design of our study, we cannot claim any causal relationship between the presence of alterations in fatty acid status and canine aggressiveness. Whether omega-3 fatty acids supplementation may be useful to reduce aggressive behaviour in the dog deserves further investigation.  相似文献   
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