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71.
This is the second in a series of three review articles on animal poisoning in Europe and focuses on cases in pet animals and horses in five European countries (Belgium, France, Greece, Italy and Spain) reported over the last decade. In the participating countries, dogs were the most commonly poisoned species, particularly younger animals. The majority of cases in companion animals resulted from exposure to insecticides, although rodenticides (especially anticoagulants and strychnine) posed a significant risk. In all five countries, horses and cats appeared to be more susceptible to plant toxins. Intoxications with herbicides, metals, household products and drugs for veterinary and human use were reported sporadically. The review demonstrates the importance of increased awareness so as to minimise poisoning episodes and emphasises the need to establish a European system for the recording of poisoning data.  相似文献   
72.
The aim of this paper was to study how maturity and maceration length affect color, phenolic compounds, polysaccharides, and sensorial quality of Cabernet Sauvignon and Tempranillo wines at three stages of grape ripening. Ripeness increased color extractability, phenolic compounds, and polysaccharide concentrations. Moreover, the proanthocyanidin mean degree of polymerization (mDP) and the percentage of prodelphinidins also increased with maturity, whereas the percentage of galloylation decreased. In general, wines from riper grapes contain higher proportions of skin proanthocyanidins. Color and anthocyanin concentration decreased when the maceration was longer, whereas polysaccharide and proanthocyanidin concentrations did the opposite. It was also detected that the mDP and the percentage of prodelphinidins decreased when the maceration was extended, whereas the percentage of galloylation increased. These data seem to indicate that proanthocyanidin extraction from seeds is clearly increased throughout the maceration time.  相似文献   
73.
The infection of stored apples by the fungus Penicillium expansum causes the contamination of fruits and fruit-derived products with the mycotoxin patulin, which is a major issue in food safety. Fungal attack can be prevented by beneficial microorganisms, so-called biocontrol agents. Previous time-course thin layer chromatography analyses showed that the aerobic incubation of patulin with the biocontrol yeast Rhodosporidium kratochvilovae strain LS11 leads to the disappearance of the mycotoxin spot and the parallel emergence of two new spots, one of which disappears over time. In this work, we analyzed the biodegradation of patulin effected by LS11 through HPLC. The more stable of the two compounds was purified and characterized by nuclear magnetic resonance as desoxypatulinic acid, whose formation was also quantitated in patulin degradation experiments. After R. kratochvilovae LS11 had been incubated in the presence of (13)C-labeled patulin, label was traced to desoxypatulinic acid, thus proving that this compound derives from the metabolization of patulin by the yeast. Desoxypatulinic acid was much less toxic than patulin to human lymphocytes and, in contrast to patulin, did not react in vitro with the thiol-bearing tripeptide glutathione. The lower toxicity of desoxypatulinic acid is proposed to be a consequence of the hydrolysis of the lactone ring and the loss of functional groups that react with thiol groups. The formation of desoxypatulinic acid from patulin represents a novel biodegradation pathway that is also a detoxification process.  相似文献   
74.
Celiac disease is a food intolerance triggered by the ingestion of gluten-containing cereals; the only therapy is a strict gluten-free diet for life. In recent years, amaranth flour has received considerable attention as an interesting source for the formulation of gluten-free products due to its high nutritional value and low content of prolamins, the toxic proteins for celiacs. The aim of this study was to characterize 40 amaranth varieties using both SDS-PAGE/immunoblotting and ELISA to assess their possible tolerance by celiac subjects. All of the amaranth samples studied showed similar binding affinities for both specific anti-gliadin antibodies and human IgAs. In most amaranth grains, the content of gluten-like proteins measured by ELISA was <20 ppm. The molecular characterization of amaranth proteins suggests that amaranth is safe for celiacs to consume. It is recommended that the most suitable amaranth varieties are those having the lowest content of proteins cross-reacting with anti-gliadin antibodies.  相似文献   
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Assessment of native plants and laboratory-scale phytoextraction tests are fundamental and preliminary steps in checking the feasibility and practice of low-cost and low-impact phytoremediation. In this study, we investigated the absorption of B by plants as a tool to remove boron in sediments from different areas of the Cecina River basin in Tuscany, Italy. The investigation was performed analyzing total and available B fraction in sediment samples as well as the B content in different tissues of native plants colonizing the contaminated areas. In laboratory scale, a phytoextraction screening test was performed. Selected high biomass crops (Brassica juncea, Zea mays, and Helianthus annuus) were evaluated in the most contaminated sample in two consecutive growing cycles. Results from field survey showed no hyperaccumulator native plant was present in the investigated areas although, high accumulation levels were found in native species from Bulera dump (Rumex crispus??259 mg?kg?1 and Poa spp??203 mg?kg?1). Results from laboratory phytoextraction tests showed a higher ability of B. juncea which removed about 18.5 mg?B?kg?1 sediment in after the two consecutive growing cycles, representing on the whole 45% of the initial available B fraction. The sediment characteristics affected by the phytoextraction processes were also discussed.  相似文献   
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The slash-and-burn system is a subsistence agronomical practice widespread in tropical areas worldwide. This system has been extensively studied,especially for its impacts on agronomical aspects and soil physicochemical properties; however, knowledge of soil microbial diversity under slash and bum is scarce. In this study, for the first time, soil bacterial diversity of three locations from Central Mozambique, where slash and burn has been practiced for different durations of the forest fallow p...  相似文献   
80.
Environmental stress as salinity can negatively affect the physiology of tomato plants. Conditions leading to a reduction of transpiration can contribute to greater tolerance to salinity. Use of kaolin-based particle film technology (PFT) may be an effective tool to control stomatal conductance and transpiration rate, thus mitigating the detrimental effect of salinity. The present three-year study has investigated the effects of kaolin application on leaf gas exchange, leaf water potential, leaf and canopy temperature of field-grown tomato, irrigated with brackish water by drip method, in southern Italy. Treatments were: (1) three salinity levels of irrigation water (electrical conductivity of water = 0.5, 5 and 10 dS m?1); (2) tomato plants treated or not with kaolin; and (3) two cultivars in each year. The increase in salinity caused the reduction of leaf water potential, stomatal conductance, net photosynthesis and transpiration rate, and the increase of leaf and canopy temperature. Kaolin has resulted in an improvement of leaf water potential, and the reduction in gas exchange variables in low-salinity conditions. Under high salinity, kaolin was effective in limiting the reductions in net photosynthesis and reducing leaf and canopy temperature. These latter variables were slightly affected by kaolin, in different ways in respect to the saline treatments; while in non-saline conditions were 0.2–0.5°C higher in the kaolin-treated plants, the situation was reversed in more saline treatment. The variation of leaf and canopy temperature shows that kaolin influences the thermal balance mainly for the dual effect of reflection of the incident radiation and partial occlusion of the stomata. Kaolin mitigated detrimental effects of salinity also on yield, contributing to the improvement of income for the farmers. The use of kaolin-based PFT may be an effective tool to alleviate salinity stress in tomato production under arid and semi-arid conditions.  相似文献   
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