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391.
European Journal of Plant Pathology - Olive (O. europaea L.) is an expanding crop in the south of Brazil. Blossom blight and typical anthracnose symptoms on fruit were observed in olive trees in an...  相似文献   
392.
Among the fungi associated with the kiwi wood diseases, the vascular pathogen Phaeoacremonium minimum can infect plants already at nursery stage, without any external symptoms. At the moment, there are not effective control strategies. The effect of soil treatments applicable in organic agriculture was evaluated in two-years experiments on potted kiwi plants artificially inoculated with P. minimum. The soil treatments were based on commercial formulations of iron chelate, silicon, neem paste, Trichoderma afroharzianum strain T22, and cover cropping with selected perennial Poaceae. Cover cropping and iron chelate treatments enhanced the iron availability for the plants and significantly reduced wood necrosis caused by the pathogen. Both treatments also produced an increase of hairy root proliferation, so the plants were able to better cope with stress conditions. Laboratory assays showed the role of iron on the pathogen growth and its pathogenesis enzyme activities.  相似文献   
393.
Fusarium head blight (FHB) of wheat heads by Fusarium culmorum causes serious yield losses and compromises the end-use quality by accumulation of mycotoxins and alteration of baking characteristics. The most promising control strategies against the disease combine adequate cropping techniques (i.e. crop rotation avoiding maize as a preceding crop) with the use of resistant varieties. Different types of resistance against this disease have been described such as the resistance to primary infection of the spikelets and the reduction of spread of the infection in other parts of the ear. In recent years, the ability of the kernels to prevent penetration of the fungus and mycotoxin accumulation has received increasing attention. Yet, the detection of kernel resistance for breeding purposes is rather difficult, as the corresponding resistance mechanisms are not fully understood. The aim of the present work is to compare different aspects of kernel resistance in order to define the most significant criteria for breeding purposes. The experimental set up included eight modern Swiss spring wheat varieties grown on small irrigated yield plots (3 × 1.5 m) inoculated at anthesis with a mixture of Fusarium culmorum isolates. Disease ratings from 7 to 28 days post-inoculation were completed with post-harvest analyses for the accumulation of the mycotoxin deoxynivalenol and different baking quality parameters. Results indicate that the accumulation of the mycotoxin deoxynivalenol in the kernels is correlated with visible symptoms on the ear before harvest. In terms of baking quality parameters, water absorption, dough softening and dough resistance are impaired in susceptible varieties after FHB infection, while resistant varieties are not affected. The results obtained here indicate that kernel resistance can be defined by low deoxynivalenol accumulation in the kernels and by stability of several baking quality parameters under conditions of high FHB infection pressure.  相似文献   
394.
ABSTRACT A polymerase chain reaction approach using degenerate primers that targeted the conserved domains of cloned plant disease resistance genes (R genes) was used to isolate a set of 15 resistance gene analogs (RGAs) from common bean (Phaseolus vulgaris). Eight different classes of RGAs were obtained from nucleotide binding site (NBS)-based primers and seven from not previously described Toll/Interleukin-1 receptor-like (TIR)-based primers. Putative amino acid sequences of RGAs were significantly similar to R genes and contained additional conserved motifs. The NBS-type RGAs were classified in two subgroups according to the expected final residue in the kinase-2 motif. Eleven RGAs were mapped at 19 loci on eight linkage groups of the common bean genetic map constructed at Centro Internacional de Agricultura Tropical. Genetic linkage was shown for eight RGAs with partial resistance to anthracnose, angular leaf spot (ALS) and Bean golden yellow mosaic virus (BGYMV). RGA1 and RGA2 were associated with resistance loci to anthracnose and BGYMV and were part of two clusters of R genes previously described. A new major cluster was detected by RGA7 and explained up to 63.9% of resistance to ALS and has a putative contribution to anthracnose resistance. These results show the usefulness of RGAs as candidate genes to detect and eventually isolate numerous R genes in common bean.  相似文献   
395.
Cardiovascular diseases (CVDs) have emerged as a major threat to global health resulting in a decrease in life expectancy with respect to humans. Thrombosis is one of the foremost causes of CVDs, and it is characterized by the unwanted formation of fibrin clots. Recently, microbial fibrinolytic enzymes due to their specific features have gained much more attention than conventional thrombolytic agents for the treatment of thrombosis. Marine microorganisms including bacteria and microalgae have the significant ability to produce fibrinolytic enzymes with improved pharmacological properties and lesser side effects and, hence, are considered as prospective candidates for large scale production of these enzymes. There are no studies that have evaluated the fibrinolytic potential of marine fungal-derived enzymes. The current review presents an outline regarding isolation sources, production, features, and thrombolytic potential of fibrinolytic biocatalysts from marine microorganisms identified so far.  相似文献   
396.
BACKGROUND AND HYPOTHESIS: We retrospectively evaluated the clinicopathologic findings and outcome predictors in dogs with Leptospira interrogans Australis serogroup infections. ANIMALS AND METHODS: The medical records of 159 dogs that had a leptospiral microscopic agglutination test (MAT) performed between 2001 and 2004 were reviewed. RESULTS: Twenty dogs met serologic criteria for either symptomatic (16 dogs) or asymptomatic (4 dogs) infection caused by Leptospira interrogans Australis serogroup. Seven of 16 symptomatic dogs died or were euthanized and 9/16 recovered. Systemic inflammatory response syndrome (SIRS) was observed in 9/16 dogs. The presence of SIRS did not affect prognosis (P = .357). C-reactive protein (CRP) and haptoglobin (Hpt) concentrations were altered in all symptomatic dogs, but results did not differ significantly between survivors and nonsurvivors (P = .08 and P = .055, respectively). Conversely, the CRP to Hpt ratio (CRP/Hpt) was significantly increased in nonsurvivors. Disseminated intravascular coagulation (DIC) was diagnosed in 7/16 dogs. DIC did not significantly affect outcome (P = .126). Multiple organ involvement was present with renal failure in 16/16, liver damage in 12/16, cardiac damage in 11/16, and muscular damage in 8/16 dogs. CONCLUSIONS AND CLINICAL IMPORTANCE: Among the evaluated clinicopathologic biomarkers, serum albumin, cardiac troponin I, CRP/Hpt, urinary albumin, and urinary total protein to creatinine ratio were found to predict outcome and warrant evaluation in larger prospective studies.  相似文献   
397.
The aim of this study was to test a pellet formulation in a sodium alginate matrix of Duddingtonia flagrans in the biological control of goat gastrointestinal helminths kept in a native pasture in a semi-arid region of Paraíba state, northeastern Brazil. An area of 2.4 ha was divided into three paddocks, where groups of seven goats ware formed. Each group received the following treatments during the months of March to August 2011: D. flagrans group, received 3g of pellets containing D. flagrans (AC001) for each 10 kg/l.w., twice a week; Moxidectin 0.2% group, received 0.2mg/kg of Moxidectin 0.2% orally, every 30 days; Control group, received 3g of pellets without fungi per 10 kg/l.w., twice a week. Each month, a tracer goat was placed in each group for 30 days and then sacrificed and necropsied. The D. flagrans group showed a greater reduction in EPG, increased weight gain, higher rates of packed cell volume and lower parasitic load burden in the tracer goats compared to Moxidectin 0.2% and Control groups. D. flagrans was efficient in controlling goat gastrointestinal helminthiasis in a semi-arid region of northeastern Brazil.  相似文献   
398.
399.
Blau H  Brazelton T  Keshet G  Rossi F 《Science (New York, N.Y.)》2002,298(5592):361-2; author reply 362-3
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400.
John Hodgson (1937–2018) is renowned worldwide as a passionate and principled researcher, dedicated to the study of interactions between grazing livestock and pasture sward, and to whole‐system management of grassland. He published over 250 scientific outputs during his 50‐year career, and inspired generations of grazing ecologists. Following his upbringing on a mixed‐livestock farm in the Yorkshire Dales, John received BSc, PhD and DSc from the University of Leeds, UK. He worked in research institutes in Hurley, England and Penicuik, Scotland, before taking a Chair in Agronomy at Massey University, New Zealand in 1986. There, he progressed to become Head of School for the Environment. John retired from university life in 2002, but never left academia. John's global research legacy is reflected in the international authorship of this memorial review. His international impact is demonstrated by the supervision of over 50 PhD students from all over the world, and by his knowledge‐sharing travels to South America and China. His peers will remember him as a thoughtful and collaborative scholar. His students will remember him as an inspiring and caring mentor. He helped to revolutionize the way that grasslands are managed, in the face of global environmental change and increasing demand on grazed systems. John lost a long battle with Parkinson's disease in October 2018 and is survived by his wife, Ruth, and five children. His own research was often dedicated to his father, Dick Hodgson, and the first author of this tribute wishes to do the same.  相似文献   
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