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In the 1970s unexpected forest damages, called “new type of forest damage” or “forest decline”, were observed in Germany and other European countries. The Federal Republic of Germany and the German Federal States implemented a forest monitoring system in the early 1980s, in order to monitor and assess the forest condition. Due to the growing public awareness of possible adverse effects of air pollution on forests, in 1985 the ICP Forests was launched under the convention on long-range transboundary air pollution (CLRTAP) of the United Nations Economic Commission for Europe (UN-ECE). The German experience in forest monitoring was a base for the implementation of the European monitoring system. In 2001 the interdisciplinary case study “concept and feasibility study for the integrated evaluation of environmental monitoring data in forests”, funded by the German Federal Ministry of Education and Research, concentrated on in-depths evaluations of the German data of forest monitoring. The objectives of the study were: (a) a reliable assessment of the vitality and functioning of forest ecosystems, (b) the identification and quantification of factors influencing forest vitality, and (c) the clarification of cause-effect-relationships leading to leaf/needle loss. For these purposes additional data from external sources were acquired: climate and deposition, for selected level I plots tree growth data, as well as data on groundwater quality. The results show that in particular time series analysis (crown condition, tree growth, and tree ring analysis), in combination with climate and deposition are valuable and informative, as well as integrated evaluation of soil, tree nutrition and crown condition data. Methods to combine information from the extensive and the intensive monitoring, and to transfer process information to the large scale should be elaborated in future.
Sabine AugustinEmail:
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The possible involvement of salicylic acid in systemic acquired resistance ofCucumis sativus againstSphaerotheca fuliginea was studied. Cucumber plants were inoculated with tobacco necrosis virus on the cotyledons and the level of endogenous salicylic acid in the first true leaf was determined by gas chromatography. Salicylic acid increased continously from the second day after virus inoculation to the fifth day, when the same leaf was inoculated withSphaerotheca fuliginea. In healthy plants, the efficiency of exogenous salicylic acid in inducing resistance was assayed by applying aqueous solutions at different times beforeSphaerotheca fuliginea inoculation. To evaluate the level of induced resistance, the following parameters were examined by light microscopy: percentage of conidial germination, length of the hyphae derived from single conidia, number of haustoria, percentage of epidermal cells with lignified walls and of necrotic cells underlying fungal hyphae. In treated plants conidial germination was reduced, the total length of the hyphae was shorter, the number of haustoria was lower and the haustorium-containing epidermal cells had more frequently lignified walls. Moreover, an evident increase in callose deposition was observed leading to the formation of oversized papillae around the penetration pegs. These results indicate that the application of salicylic acid before inoculation withSphaerotheca fuliginea reduces the intensity of the infectious process and that salicylic acid is involved in the expression of systemic resistance in cucumber challenged by the biotrophic pathogenSphaerotheca fuliginea.  相似文献   
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Therapy of canine dirofilariois due to Dirofilaria repens is indicated for dogs suffering from clinical signs of this disease, such as dermal swelling, sub-cutaneous nodules and pruritus. It is also important in order to decrease the risk of infection to other dogs and humans in the vicinity of the infected animal when suitable mosquito vectors are present. Combined therapy with the arsenic adulticide melarsomine and the avermectin microfilaricidal doramectin was effective in clearing infection with D. repens in a dog. The number of microfilariae dropped from 17 microl(-1) blood pre-treatment to 7 microl(-1) following the first adulticide injection and reached 0 a day after the microfilaricidal administration. The dog remained negative for D. repens microfilaremia during a follow-up period of 90 days. Euthanasia and necropsy performed 3 months after the initiation of therapy due to a progressive neoplastic disease revealed no evidence of filariae.  相似文献   
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Although hardly any polyunsaturated fatty acids (PUFAs) are present in the endproduct, the ingredients used for the production of beer contain a high concentration of PUFAs, such as linolic and linolenic acid. These compounds are readily oxidized, resulting in the formation of lipid-derived products that reduce the taste and quality of beer enormously. During mashing relatively high amounts of PUFAs are exposed to atmospheric oxygen at a relatively high temperature. This makes mashing a critical step in the brewing process with regard to the formation of lipid-derived off-taste products. F1 phytoprostane (PPF1) changes in antioxidant capacity and monohydroxy fatty acids (OH-FAs) were used as markers for the detection of oxidative damage to fatty acids during mashing. The pattern of OH-FA formation indicates that enzymatic oxidation of PUFAs is more important than nonenzymatic oxidation during the mashing process. Nevertheless, substantial nonenzymatic radical formation is evident from the increase of specific OH-FAs and PPF1s. It was found that a low oxygen tension reduces oxidative damage and gives a high antioxidant capacity of the mashing mixture. This indicates that mashing should be done under low oxygen pressure.  相似文献   
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Ruminants, which have a central place in the food chain, ingest soil that may contain pollutants. The bioaccessibility of three different polycyclic aromatic hydrocarbon compounds from soil was studied using an in vitro model based on the digestive tract of cows. For this purpose, pasture soil was spiked with (14)C radio-labeled compounds, aged, and then exposed to conditions which simulated the digestive compartments of the rumen, abomasum, and intestines. Our results show that aging generally reduced the bioaccessibility of all the compounds tested. Total bioaccessibilty in the first digestive compartment, i.e., the rumen, depended on the considered compound: elevated for phenanthrene (17-24%), moderate for pyrene (6.6-8.1%), and low for benzo[ a]pyrene (2.3-3.6%). Bioaccessibility was very low in abomasal acidity (generally <2%) and intestinal colloids (<8%). The liquid phases of intestinal medium successfully extracted compounds from freshly contaminated soil (25-28%), but the bioaccessibilty dropped markedly after aging (17% for phenanthrene and <9% for the more lipophylic compounds). Total bioaccessibilty in this in vitro model ranged from 11% for benzo[ a]pyrene in aged soil to 58% for phenanthrene in freshly contaminated soil, and the bioaccessibility of this latter compound was always higher compared to pyrene or benzo[ a]pyrene. Residual soil contained around half of the initial load, the highest residual levels being of benzo[ a]pyrene, which confirms the observed bioaccessibility.  相似文献   
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  1. Seamounts host some of the most important deep-sea ecosystems. The unique environmental characteristics of seamounts sustain rich biological hot spots, which, in recent times, have suffered the effects of intense fishing pressure.
  2. Biodiversity and vulnerability data are extremely scarce for Mediterranean seamounts, and this, in addition to the complex socio-economic and juridical status of offshore sites, results in difficulty in identifying the best management strategies.
  3. An extensive remotely operated vehicle (ROV) survey was used to characterize the megabenthic assemblages of the summits of two upper bathyal seamounts, Ulisse and Penelope (Ligurian Sea, north-west Mediterranean Sea). The biogeographic implications of these findings and the possible environmental factors favouring the occurrence of these communities are discussed.
  4. High densities of abandoned, lost, or otherwise discarded fishing gear (mainly longlines) and a reduction in the average size of the fragile and slow-growing habitat-forming gorgonian Callogorgia verticillata indicate the occurrence of high levels of anthropogenic impacts on the summit regions, which are fishing grounds for artisanal and recreational fishers.
  5. The recovery of fishing data describing the first catches in the 1970s proved to be useful in inferring the short- and long-term effects of fishing practices in these previously unexploited offshore areas. In particular, the local extinction of demersal top predators, subjected to exceptional catches nearly 50 years ago, highlights the slow recovery rate of such species.
  6. Criteria defining vulnerability are discussed for the two study areas, and specific conservation actions, including the creation of regulated protected areas, are proposed.
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