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In last years, following the increased canine life expectancy and the rising attention pet-owners devote to their animals, several authors have carried on investigations concerning new techniques to early identify canine prostatic disorders that might affect the dog's quality of life. Prostatic disorders often have an asymptomatic onset and their early diagnosis is difficult: hence, they are usually identified at an advanced stage, only. Traditionally, the diagnosis of prostatic disorders is based on noninvasive tools, such as transrectal and abdominal palpation, seminal or prostatic fluid evaluation, and urinalysis and imaging. On the other hand, a definite diagnosis of prostatic abnormalities could be achieved through prostatic parenchyma Fine Needle Aspiration (FNA) or biopsy. However, these investigations are performed rarely because of their invasiveness. Thus, several authors investigated canine serum biomarkers in order to achieve an earlier diagnostic timing and to apply therapeutic strategies for better outcomes. The Canine Prostatic Specific Esterase (CPSE) has been identified as a suitable biomarker to be included in a prostate health screening program, following the model of prostate-specific antigen (PSA) in human medicine. A higher CPSE in dogs suffering from several prostatic diseases, such as benign prostatic hyperplasia, bacterial prostatitis, or prostatic carcinoma, was reported in literature. Thanks to the potential usefulness in clinical practice, further studies should investigate the potential role of CPSE in monitoring the medical treatment success in the male reproductive system. Moreover, the spreading availability of serum biomarkers, easily carried out on blood samples in clinical practice, could assure a more accurate evaluation of the actual prevalence of prostatic disorders. The CPSE is actually recognized as a promising diagnostic tool for the detection of prostatic disorders in a "prostate health screening program," in order to properly select those patients requiring further more accurate and expensive diagnostic investigations.  相似文献   
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When the esca-associated fungi Phaeomoniella chlamydospora (Pch), Togninia minima (Tmi) and Fomitiporia mediterranea (Fme) were grown in liquid stationary cultures, it was seen that they were able to live in media containing resveratrol (RES) or tannic acid (TA) as the sole carbon source and that the fungi were able to convert both compounds. Particular attention is paid here to detecting RES and TA conversion. Pch, Tmi and Fme were partially inhibited by RES or TA. Pch, Tmi and Fme produced extracellular tannase, laccase and peroxidase enzymes in liquid or agarized cultures, whether glucose was present or not. When colonies of Pch, Tmi and Fme were confronted, they showed spatially and temporally heterogeneous patterns of laccase and peroxidase activity. The results indicate the non-synergistic, competitive association of Pch and Tmi and the inhibition of Fme growth. Muconic acid, a well-known intermediate in a large number of lignin and phenol oxidative processes, can partly or completely inhibit the lignolytic agent Fme, but is tolerated by Pch and Tmi. An explanation for wood pigmentation patterns by Pch, Tmi and Fme is given.  相似文献   
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A vineyard of Vitis vinifera cv. Sangiovese was surveyed for incidence of esca and xylem sap collection. Sap samples were collected from healthy vines and from those with dual infection by Phaeomoniella chlamydospora (Pch) and Togninia minima (Tmi) or triple infection by Pch, Tmi and Fomitiporia mediterranea (Fme), during each early spring in a 3-year period (2001–2003). In order to analyse the possible trends in the climatic data, temperature and rainfall were assessed. At sap harvesting, aliquots of sap were assayed for phytotoxicity and extracted with ethyl acetate for phytotoxin recovery. Moreover, the exopolysaccharide (EPS) content was evaluated on several sap samples during the bleeding period. Conidia of Pch and Tmi, mycelium of Fme and their secondary metabolites were found in the sap of the esca-affected vines, indicating that the pathogens and their by-products together with some defence substances were accumulated and then translocated. Bioactivity tests showed toxicity of the sap from esca-affected vines to healthy detached leaves of cv. Sangiovese. The daily amount of sap, the pH, and the volume (Jv) and solute (Js) fluxes were analysed as a function of the infecting fungi. Pullulan, glucogalactomannan(s) and arabinogalactan(s) are the main EPS in the esca-infected vines, whereas in the sap of healthy vines no traces of pullulan were found. Scytalone and isosclerone usually produced in vitro by Pch and Tmi were also detected in the sap of vines infected by Pch and Tmi or by Pch, Tmi and Fme. The endogenous phytohormone content of healthy vines evaluated by the cutting bioassay was different from that of infected vines. Four phenolics belonging to three classes e.g., benzoic acid derivatives, stilbenes and flavonol-glycosides were separated and identified by HPLC.  相似文献   
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Assessing air quality in street canyons is a crucial concern, as the highest pollution levels and threshold exceedances are usually experienced within this kind of urban streets. A brief overview based on experimental studies and modelling techniques undertaken in literature is presented, including characteristic features affecting wind flow and pollutant dispersion within street canyons. In this work, a numerical street canyon model intercomparison has been performed in a typical urban canyon in Florence, Italy. In particular, STREET, Canyon Plume Box Model (CPBM) and Operational Street Pollution Model (OSPM) have been applied to compute the street-level 1-h carbon monoxide (CO) concentrations. In addition, the CALINE4 model has been applied to test the site morphology. Input data cover a 1-year time period and include meteorological observations as well as measured traffic volumes and driving speeds. Hourly road emissions have been calculated using the COPERT methodology taking into account vehicle fleet, traffic flows and driving speed, as well as ambient temperature to account for cold overemissions. A preliminary experimental data analysis has been carried out in order to investigate the dependence of observed CO concentrations on meteorological and traffic parameters. Hourly CO concentrations observed over the full year have been used to compare the STREET, CPB and OSP models, resulting in a detailed statistical analysis carried out by wind sector as well as on a seasonal basis.  相似文献   
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The soil organic matter content represents a huge reservoir of plant nutrients and an effective safeguard against pollution; beside it can sequestrate atmospheric CO2. Since 1966 up to now in the Southeast Po valley (Italy), the soil organic C (SOC) and total N (TN) dynamics in the 0–0.40 m soil layer under a maize–wheat rainfed rotation are studied as influenced by organic and mineral N fertilizations. Every year in the same plots cattle manure, cattle slurry, and crop residues (i.e. wheat straw and maize stalk) are ploughed under to 0.40 m depth at a same dry matter rate (6.0 and 7.5 t DM ha−1 year−1 after wheat and maize, respectively) and are compared to an unamended control. Each plot is splitted to receive four rates of mineral fertilizer (0–100–200–300 kg N ha−1). In the whole experiment, in 2000 SOC concentration was lower than in 1966 (6.77 and 7.72 g kg−1, respectively), likely for the deeper tillage that diluted SOC and favoured mineralization in deeper soil layer. From 1972 to 2000 SOC stock did not change in the control and N fertilized plots, while it increased at mean rates of 0.16, 0.18, and 0.26 t ha−1 year−1 with the incorporation of residues, slurry and manure, corresponding to sequestration efficiencies of 3.7, 3.8 and 8.1% of added C with the various materials. TN followed the same SOC dynamic, demonstrating how it depends on the soil organic matter. Manure thus confirmed its efficacy in increasing both SOC content and soil fertility on the long-term. In developed countries, however, this material has become scarcely available; slurry management is expensive and implies high environmental risks. Moreover, in a C balance at a farm (or regional) scale, the CO2 lost during manure and slurry stocking should be considered. For these reasons, the incorporation of cereal residues, even if only a little of their C content was found capable of soil accumulation, appears the best way to obtain a significant CO2 sequestration in developed countries. Our long-term experiment clearly shows how difficult it is to modify SOC content. Moreover, because climate and soil type can greatly influence SOC dynamic, to increase CO2 sequestration in cropland, it is important to optimize the fertilization within an agricultural management that includes all the agronomic practices (e.g. tillage, water management, cover crops, etc.) favouring the organic matter build up in the soil.  相似文献   
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The recessive gene ol-2 confers papilla-associated and race-non-specific resistance to tomato powdery mildew caused by Oidium neolycopersici. In order to facilitate marker assisted selection (MAS) in practical breeding programmes, we identified two simple sequence repeat (SSR) markers and one cleaved amplified polymorphic sequence (CAPS) marker which are linked to the resistance locus and co-dominantly inherited. Aiming to provide a base for ol-2 positional cloning, we used a large segregating F2 population to merge these markers with all the ol-2 linked amplified fragment length polymorphism (AFLP®) markers previously identified in an integrated genetic map. By screening a tomato bacterial artificial chromosome (BAC) library, we detected two BAC clones containing two expressed sequence tags (ESTs) homologous to the gene mlo, responsible for powdery mildew resistance in barley, as well as an ol-2-linked marker. Chromosomal mapping by Fluorescence in situ Hybridization (FISH) revealed major signals of the two BAC DNAs in the pericentromeric heterochromatin of the short arm of chromosome 4, in the same region where the ol-2 gene was previously mapped. The genetic and cytogenetic co-localisation between ol-2 and tomato mlo-homologue(s), in addition to the similarity of ol-2 and mlo resistances for both genetic and phytopathological characteristics, suggests that ol-2 is likely a mlo-homologue. Thus, a homology-based cloning approach could be more suitable than positional cloning for ol-2 isolation.  相似文献   
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