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11.
A series of 1-(3-pyridyl)-1-substituted-but-3-yn-1-ols and some related compounds were synthesised and tested for antifungal activity against eight phytopathogenic fungi of different taxonomic classes. High activity was shown in particular against Sphaerotheca fuliginea on Cucumis sativus. The compounds containing aromatic substituents gave the best results, not only in protectant but also in systemic and eradicant tests. The quantitative structure-activity relationship suggests that steric effects play an important role in determining fungicidal activity.  相似文献   
12.
Twenty-three acetylenic or halovinyl carbonyl compounds with heterocyclic substituents were synthesised and tested in vivo against eight phytopathogenic fungi of different taxonomic classes. Some of them were fungicidal against Uromyces appendiculatus on Phaseolus vulgaris, though none showed a wide spectrum of activity.  相似文献   
13.
Lysinoalanine (LAL) and ornithinoalanine (OAL) are unnatural amino acids that can be formed in food submitted to thermal treatment, especially in alkaline conditions. The paper presents an optimization of the synthetic procedure for the preparation of a standard of OAL that could be very useful to study the toxicological and nutritional consequences of the presence of OAL in food. In the meantime, it was possible to develop a method based on nuclear magnetic resonance for the diastereomeric characterization of LAL and OAL without derivatization. Interest in this method is based on the known differences in the nephrotoxicity of the two diastereisomers of LAL.  相似文献   
14.
A novel system was investigated, finalized to reduce the impact of highly polluting wastewaters, and based on combined actions of catalytic oxidations and microbial biotechnologies. Olive oil mill wastewaters (COD 10,000-100,000 mg O(2)/L) were oxidized up to 80-90% by stoichiometric amounts of dilute hydrogen peroxide (35%) and in the presence of water soluble iron catalysts, either Fe(II) or Fe(III), at concentrations up to 1% w/w and more, i.e., much larger than those reported for conventional Fenton processes. In the combined action, the mineralization activity of a selected microbial consortium was used to degrade residual volatile and nonvolatile organic compounds into CO(2) and biomass. The results of this search could suggest an improved operational methodology capable to reduce the potential impact of wastewater.  相似文献   
15.
A laboratory-prepared total protein extract (TPE) and a lupin protein isolate (LPI-E) produced in a pilot plant were submitted to a detailed two-dimensional (2DE) proteomic investigation. Recent findings have indicated that in an established rodent model of hyperlipidemia, moderate daily intakes of LPI-Es lead to a reduction of total and low-density lipoprotein cholesterol levels, and the knowledge of the actual composition of the protein sample used in that study is at the basis of further structure/action investigations. The experimental results indicate that the semi-industrial procedure used for the production of LPI-E damages only marginally the proteins. It does, however, cleave some disulfide bridges and induce mild proteolysis, as confirmed by the higher number of resolved protein spots in the low Mr and acidic pI region of the 2DE map. Out of 72 spots submitted to mass spectrometry and compared with available protein databases, 42 correspond to fragments of beta-conglutin, the 7S globulin of lupin, spanning between positions 37 and 495 of the protein sequence. Using the bioinformatic tool BlastP, these peptides were compared to the alpha'-subunit of beta-conglycinin, the 7S globulin of soybean, this being the most active hypocholesterolemic component of soybean protein, as shown by in vitro and in vivo experiments. At least 18 peptides derived from beta-conglutin, having a percentage identity higher than 50% and a similarity percentage higher than 70% vs the alpha'-subunit of beta-conglycinin, are likely candidates to be the biologically active components of lupin protein.  相似文献   
16.
The target of the present work was the chemical, technological, and sensorial characterization of the brown polymers (foaming fractions) of freshly prepared espresso coffee. The total foaming fraction (TFF) was precipitated with ammonium sulfate from the defatted freshly prepared beverage and then subfractionated by adding 2-propanol/water to give an insoluble fraction (foaming fraction A, FFA) and a soluble fraction (foaming fraction B, FFB). The former is almost colorless, has a higher molecular weight and a lower nitrogen content, and contains mostly polysaccharides, whereas the latter has a lower molecular weight and a higher protein/melanoidin content, which results in a darker color. FFB showed greater foaming capability, but FFA contributed to the stability of the foam. FFB was further fractionated with solid-phase extraction and characterized by different analytical methods (size exclusion chromatography, UV, HPLC-DAD, 1H NMR). All of the melanoidin-rich fractions showed antioxidant properties with the 2,2-diphenyl-1-picrylhydrazyl hydrate method.  相似文献   
17.
A simple HPLC method was developed to distinguish between 'poisonous' and 'non-poisonous' chemotypes of Ferula communis. The method was performed on a C8 reverse phase analytical column using a binary eluent (aqueous TFA 0.01%-TFA 0.01% in acetonitrile) under gradient condition. The two chemotypes showed different fingerprints. The identification of five coumarins and eleven daucane derivatives by HPLC-diode array detection (HPLC-DAD) and HPLC-MS is described. A coumarin, not yet described, was detected.  相似文献   
18.
The combination of chemical oxidation (Fenton reaction) and biological treatment processes is a promising technique aiming to reduce recalcitrant wastewater loads. Preliminary tests were carried out on two widely used toxic and non-biodegradable pesticides, namely, Dazomet and Fenamiphos. The chemical reaction was employed as a pre-treatment step for the conversion of the substrates into oxygenated intermediates that were easily removed by means of a final biological treatment. In the combined action, the mineralisation activity of a selected microbial consortium was used to degrade residual volatile and non-volatile organic compounds into CO2 and biomass.  相似文献   
19.
The objective of this study was to monitor the changes in isoflavone content in different plant organs (leaves, stems, roots) during the crop growth stage of three cultivars of Lupinus albus (white lupin) under field conditions, taking into account sowing time effects (autumn and early spring) and cultivar effects. Three sampling dates (from late vegetative to late grain growth stages) were evaluated. Seven isoflavones and four flavonoids were identified by LC-ESI-MS analysis. The isoflavone content was higher in leaves than in stems, and it was highest before flowering, whereas it decreased during maturity. Autumn-sown plants showed higher isoflavone content than early spring-sown plants, especially in late vegetative and early reproductive stages. Genistein 7- O-glucoside was the main isoflavone of leaves and stems in the late vegetative stages of early spring sowing, whereas genistein was the main isoflavone under autumn sowing. Variation among cultivars affected only marginally the total isoflavone content. No isoflavones were detected in seeds.  相似文献   
20.
The wood tick Ixodes ricinus, one of the most common arthropod-borne disease vectors, is of increasing relevance for human and animal health in Europe. The aim of this study was to determine the relative contribution of several abiotic and biotic factors potentially affecting questing activity and local abundance of I. ricinus in Italy, considering the scale at which these factors interact with the host-seeking ticks. Within EDEN, a large-scale EU collaborative project on eco-epidemiology of vector-borne diseases, we collected questing ticks for three consecutive years using a standard protocol at eleven sites in the Italian Alps and Apennines. A total of 25 447 I. ricinus were collected. All sites showed the same annual pattern of tick activity (bimodal for nymphs and unimodal for larvae and adults), although the abundance of nymphs was statistically different between sites and years. A Generalized Linear Mixed Model and a Linear Mixed Model fitted to data for nymphs, showed that while the principal variables affecting the local abundance of questing ticks were saturation deficit (an index combining temperature and relative humidity) and red deer density, the most important variable affecting questing nymph activity was saturation deficit. As for the timing of seasonal emergence, we confirmed that the threshold temperature at this latitude for larvae is 10°C (mean maximum) while that for nymphs is 8°C.  相似文献   
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