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81.
82.
Plant Foods for Human Nutrition - Interest in quinoa as a functional food ingredient is currently emerging. The flours from white, red and black quinoa seeds were analysed in terms of total...  相似文献   
83.
Three different regeneration systems, viz. regeneration through callus cultures using embryonic explant, direct regeneration using shoot bud/nodal segments as explant and regeneration through cell suspension culture using cotyledonary explant (for the induction of transgenic callus for suspension culture) were evaluated to see their effect on transfer of Cry1A(b) gene to Punica granatum L. cv. Kandhari Kabuli through Agrobacterium mediated transformation. Pre-conditioning and co-cultivation durations had a marked effect on transformation frequency of different explants. Out of different explants used (embryo, shoot bud, and cotyledon) for different regeneration systems cotyledonary explant showed highest putative transformation frequency (13.54%) inducing callus on selective medium for carrying out cell suspension culture to regenerate transgenic shoots. Despite of the highest transformation frequency obtained from the cotyledon explant, the plating efficiency of the transgenic cells generated through the transgenic callus (callus formed from the cotyledonary explant) during cell suspension culture was found to be very low (0.7%). Thus the plating efficiency has also played worth mentioning role in the regeneration of transformants following cell suspension culture. Among the three regeneration systems, regeneration through callus cultures using embryonic explant was found to be best for regeneration of transformants. The highest per cent regeneration of 23.33 was obtained from the putative transgenic embrogenic calli. Successful genetic transformation in the transformed plantlets was confirmed by PCR analysis. The transformation system thus developed is valuable and may be used to produce insect resistant trees.  相似文献   
84.
Journal of Plant Diseases and Protection - Crown and leather rot of strawberry caused by Phytophthora spp. are major soil diseases of cultivated strawberry...  相似文献   
85.
Present research in Germany on water, wind, and tillage erosion is examined. Existing soil‐protection strategies, laws, and guidelines are outlined. These are the result of extensive scientific investigations and the adoption of existing international knowledge. The most common methodologies currently used in Germany are reviewed. They allow an estimation of the water‐ and wind‐erosion risks as well as methods for their reduction. The results enable an aim‐orientated, site‐specific, risk‐adequate approach to implementing control measures in an easily understood framework. The most important remaining research problems are explained.  相似文献   
86.
Our goal was to reconstruct the late eighteenth century forest vegetation of the Prignitz region (NE Germany) at a scale of 1:50,000. We also wanted to relate the historical forest vegetation to the actual and potential natural vegetation. For these purposes, we selected 15 woody species and transferred relevant data found in historical records from various sources together with the recent localities of (very) old individuals belonging to these woody species into ArcView GIS. Following multi-step data processing including the generation of a point density layer using a moving window with kernel estimation and derivation of vegetation units applying Boolean algebra rules together with information on site conditions, we derived 17 forest communities corresponding to the potential natural vegetation. We were able to reconstruct the historical forest vegetation for 90% of the forest area ca. 1780. Only two of the 17 forest communities covered large parts of the forested area. The oak forest with Agrostis capillaris covered about 44% of the total forest area, and alder forests on fenland made up about 37%. Oak-hornbeam forests with Stellaria holostea comprised slightly less than 6% of the forest area, while all other forest communities comprised less than 1%. The historical forest vegetation is more similar to the potential forest vegetation and quite different from the actual forest vegetation because coniferous tree species currently cover approximately two-thirds of the actual forest area. The most beneficial result of this study is the map of high-resolution historical vegetation units that may serve as the basis for various further studies, e.g., modelling long-term changes in biodiversity at the landscape scale.  相似文献   
87.
Background: Nitrogen losses is an economic problem for wheat production and a high risk to the environment. Therefore, improved N fertilizer management is a key to increasing the N efficiency and minimizing N losses. To increase N efficiency, enhanced fertilizers such as urea combined with urease inhibitor can be used. Aims: The aim of present study was to evaluate the effects of different N forms on grain storage protein subunits in winter wheat and to examine whether the observed changes correlate with parameters of baking quality. Methods: The investigation was performed over two consecutive years at two locations in Germany. Protein subunits were analyzed by SDS‐PAGE. Results: Protein concentrations were similarly increased after fertilization with ammonium nitrate and urea + urease inhibitor. Analysis of the individual storage protein fractions indicated that both fertilizers specifically enhanced ω‐gliadins and HMW glutenins, but the effect was more pronounced in the ammonium nitrate treatment. Application of urea + urease inhibitor had greater influence on the protein composition and resulted in higher specific baking volume as well as the best fresh keeping ability, in comparison with urea treatment. Conclusion: Considering that the urea + urease inhibitor treatment resulted in almost comparable improvements of NUE and baking quality, with the additional benefit of reduced N losses in combination with easy handling, urea + urease inhibitor can be recommended as a viable alternative to both urea alone and ammonium nitrate treatments. This opens up an opportunity for the reduction of N loss in wheat production when use of urea is preferred.  相似文献   
88.
Hypersensitivity dermatitides (HD) are commonly seen in cats, and they are usually caused by environmental, food and/or flea allergens. Affected cats normally present with one of the following clinical reaction patterns: head and neck excoriations, usually symmetrical self-induced alopecia, eosinophilic skin lesions or miliary dermatitis. Importantly, none of these clinical presentations is considered to be pathognomonic for HD skin diseases, and the diagnosis of HD is usually based on the exclusion of other pruritic diseases and on a positive response to therapy. The objectives of this study were to propose sets of criteria for the diagnosis of nonflea-induced HD (NFHD). We recruited 501 cats with pruritus and skin lesions and compared clinical parameters between cats with NFHD (encompassing those with nonflea, nonfood HD and those with food HD), flea HD and other pruritic conditions. Using simulated annealing techniques, we established two sets of proposed criteria for the following two different clinical situations: (i) the diagnosis of NFHD in a population of pruritic cats; and (ii) the diagnosis of NFHD after exclusion of cats with flea HD. These criteria sets were associated with good sensitivity and specificity and may be useful for homogeneity of enrolment in clinical trials and to evaluate the probability of diagnosis of NFHD in clinical practice. Finally, these criteria were not useful to differentiate cats with NFHD from those with food HD.  相似文献   
89.
Journal of Plant Diseases and Protection - Although short-wavelength light and especially UV radiation can induce resistance in plants against herbivorous insects, the optimal wavelengths, light...  相似文献   
90.
Many different fungi grow indoors as mold in the presence of moisture. Some of these fungi can cause allergic or toxic reactions, while a few may cause infections in susceptible individuals. A comprehensive treatment of this complex topic would take volumes. Therefore many groups search for alternative management strategies of these fungi. It has been tested if the growth of nine fungi (Alternaria alternata, Botrytis cinerea, Cladosporium herbarum, Fusarium culmorum, F. solani, F. verticillioides, Mucor sp., Penicillium sp. and Trichoderma sp.) which are common in interior buildings could be inhibited by mixing lignin into wall plaster. In maltextract agar lignin concentrations above 10 % inhibited mould growth except for Penicillium sp. However, none of the mould species showed and degradation of lignin. Further investigations on a lignin-plaster-agar, which contained only plaster as nutrient and had a high pH at 8, showed no inhibition on the tested fungi (Alternaria alternata, Fusarium verticillioides, Mucor sp., Trichoderma sp. and Penicillium sp.) at concentrations up to 5 %. Higher lignin concentrations lead to insufficient quality of building materials, e. g. cracking. Furthermore the color of the building materials turned from greyish-white in an exotherm reaction into brown, become not any more suitable for construction purposed.  相似文献   
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