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41.
The aim of this study was to compare the quality characteristics and mineral content of the fiber from male and female cashmere goats raised under different management systems. Male and female Raeini cashmere goats (<1.5 years of age, n = 48) were selected from flocks raised at a government breeding station or raised commercially under either rural or nomadic conditions. The staple length, cashmere fiber diameter, coefficient of variation for fiber diameter, percentage of cashmere in a fleece, percentage of guard hair in a fleece and cashmere tenacity averaged 4.6 ±0.1 cm, 18.0 ±0.1 μm, 20.9 ± 0.4%, 66.1 ± 1.5%, 33.8 ± 1.5% and 1.8 ± 0.2 gf/tex, respectively. The sulfur, copper and zinc content of the cashmere averaged 2.8 ± 0.1%, 0.00065 ± 0.00002% and 0.01276 ± 0.00025%, respectively. Rearing method significantly affected staple length, coefficient of variation of fiber diameter, cashmere tenacity and copper content. Males had a higher coefficient of variation of fiber diameter and cashmere tenacity than females (P < 0.05).  相似文献   
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Hippuric acid (HA) in cattle urine acts as a natural inhibitor of soil N2O emissions. As HA concentration varies with diet, we determined critical HA levels. We also tested the hypothesis that the inhibition occurs because the HA breakdown product benzoic acid (BA) inhibits denitrification rates. During a 64-day incubation, we quantified emissions from artificial urine varying in HA, BA and glycine (Gly) concentrations, added to a sandy pasture soil. Increasing HA concentration from 0.4 to 5.6 mmol kg−1 soil significantly decreased the average N2O flux by 54%. At 3.9 mmol kg−1 soil, denitrification levels were 50% reduced for BA as compared to Gly. We conclude that HA inhibits both denitrification and N2O emission, at least partly through a BA mechanism.  相似文献   
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Abstract

In order to evaluate the effects of water deficit stress and foliar application of zinc (Zn) and iron (Fe) nanoparticles on physiological characters and seed yield of pinto bean, an experiment was designed as a split factorial design based on randomized complete blocks with three replications in two growing seasons (2016–2017 and 2017–2018). Treatments were included water deficit stress (normal irrigation and water deficit stress in 50% flowering), foliar application of nano-fertilizers (control, nano-Zn (1.5?g L?1), nano-Fe (2?g L?1) and combination of nano-Zn and nano-Fe) and four cultivars of pinto bean (Sadri, Coosha, Cos16, and Ghaffar). The results showed that the soluble sugars and proline content was increased under water deficit. Water deficit stress through decreasing chlorophyll and relative water content of leaves as well as the iron and zinc content of seeds, decreased seed yield and quality. The application of nano-fertilizers of zinc and iron enhanced antioxidant enzymes activity, proline and soluble sugars content as well as leaf area. Also applied nano-fertilizers improved seed quality in terms of protein content. According to obtained results the effect of foliar spray of nano-fertilizers on iron and zinc content of seeds regards to bean cultivars was different. It was concluded that the foliar application of iron combined zinc nano-fertilizers can be useful in pinto bean cultivars under water deficit stress. In both normal and water deficit Cos16 cultivar showed the better amount of studied characteristics compared to other cultivars. The results of cluster analysis of these cultivars confirmed the superiority of Cos16 cultivar.  相似文献   
45.
BACKGROUND: Although pyrimethamine (Tindurin) appears to be effective in the prevention and treatment of some infectious diseases, very little information exists on its unpredictable properties. We design this study to evaluate its anti-tumoral effect on a model of cell line. METHODS: The cytotoxic influence of Pyrimethamine on prostate cell line was investigated using an in vitro colometric assay. The potential modulatory effects on metastasis, apoptosis, and immortality characteristics of cells were assessed with gelatin zymography, terminal deoxyribonucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay and telomeric repeat amplification protocol, respectively. RESULTS: Cytotoxicity analysis of pyrimethamine revealed a dose-dependent fashion. An apoptotic influence of pyrimethamine was also confirmed by data obtained from TUNEL assay. Dose-dependent inhibitory effect on matrix metalloproteinases (MMP) was seen in pyrimethamine. A potent inhibitory effect of pyrimethamine was also established by data achieved from TRAPeze telomerase detection kit. CONCLUSIONS: Collectively, as induction of apoptosis together with MMP and telomerase inhibition could be indicative of cancer treatment, pyrimethamine might be considered as a chemopreventative agent in cancer.  相似文献   
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The aim of this study was to compare the quality characteristics and mineral content of the fiber from male and female cashmere goats raised under different management systems. Male and female Raeini cashmere goats (<1.5 years of age, n = 48) were selected from flocks raised at a government breeding station or raised commercially under either rural or nomadic conditions. The staple length, cashmere fiber diameter, coefficient of variation for fiber diameter, percentage of cashmere in a fleece, percentage of guard hair in a fleece and cashmere tenacity averaged 4.6 ±0.1 cm, 18.0 ±0.1 m, 20.9 ± 0.4%, 66.1 ± 1.5%, 33.8 ± 1.5% and 1.8 ± 0.2 gf/tex, respectively. The sulfur, copper and zinc content of the cashmere averaged 2.8 ± 0.1%, 0.00065 ± 0.00002% and 0.01276 ± 0.00025%, respectively. Rearing method significantly affected staple length, coefficient of variation of fiber diameter, cashmere tenacity and copper content. Males had a higher coefficient of variation of fiber diameter and cashmere tenacity than females (P < 0.05).  相似文献   
48.
Abiotic and biologically informed classifications are often used in conservation planning as coarse-filter surrogates for species. The relationship between these surrogates and the distribution of species is commonly assumed, but rarely assessed by planners. We derived four abiotic and eight biologically informed classifications of stream reaches to serve as surrogates for biodiversity patterns in the Wet Tropics bioregion, Queensland, Australia. We used stream reaches as planning units and, as conservation targets for each surrogate, we used two percentages – 10% and 30% – of the total stream reach length occupied by each class. We then derived minimum sets of planning units to meet targets for each surrogate and tested the effectiveness of the surrogates by calculating the average achievement of the same targets for predicted distributions of 28 fish species. Our results showed that neither abiotic nor biologically informed classifications were good at representing freshwater fish species; in fact none of the surrogates led to average representation of species better than randomly selected planning units. There were two main reasons for this poor performance. First, none of the surrogates had high classification strength or informativeness about compositional change in fish species within the study region. Second, frequency distributions of probabilities of occurrence for most fish species were strongly right-skewed, with few stream reaches having high probabilities. Combined, these results meant that selection of stream reaches to achieve surrogate targets was effectively random with respect to probabilities of fish species occurrence, leading to poor representation of fish species. We conclude there is a limited basis for using coarse-filter surrogates to represent freshwater fish diversity in this region, and that there is a clear need for research in this as well as other regions if planners are to understand the limitations associated with coarse-filter surrogates for representing freshwater biodiversity more broadly.  相似文献   
49.
Summary Colour is the major contributor to the total ornamental value of a flower. The combination of biochemical knowledge and genetic engineering technology has resulted in the addition of a new colour to the existing colour range of Petunia hybrida. This has been achieved by expression of the maize dihydroflavonol-4-reductase (dfr) gene in a suitable petunia acceptor which leads to the accumulation of pelargonidin-derived pigments in flowers. The resulting flower colour, however, was a pale brick-red, which is commercially unattractive in petunia.Our objective was to produce a product suitable for commercialisation by introducing the dfr gene into our breeding material via normal sexual recombination. Although the initial transformant exhibited many negative characteristics, first analyses indicated that it was feasible to obtain suitable material for creating commercial hybrids. Experimental hybrids based on F4 lines were obtained with improved phenotypic expression of the orange flower colour in combination with a good general performance.In order to assess consumer-related characteristics, selected experimental hybrids were tested under field conditions. All transgenic plants had a normal appearance when compared with non-transgenic control plants. No linkage was observed between the transgenic trait and any negative characteristic. From these studies it can be concluded that through a combination of biochemistry, breeding and genetic engineering, it is possible to generate unique flower colours in a cultivars with commercial potential.  相似文献   
50.
Soils are the major source of the greenhouse gas nitrous oxide (N2O) to our atmosphere. A thorough understanding of terrestrial N2O production is therefore essential. N2O can be produced by nitrifiers, denitrifiers, and by nitrifiers paradoxically denitrifying. The latter pathway, though well-known in pure culture, has only recently been demonstrated in soils. Moreover, nitrifier denitrification appeared to be much less important than classical nitrate-driven denitrification. Here we studied a poor sandy soil, and show that when moisture conditions are sub-optimal for denitrification, nitrifier denitrification can be a major contributor to N2O emission from this soil. We conclude that the relative importance of classical and nitrifier denitrification in N2O emitted from soil is a function of the soil moisture content, and likely of other environmental conditions as well. Accordingly, we suggest that nitrifier denitrification should be routinely considered as a major source of N2O from soil.  相似文献   
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