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211.
Sonja Brodt Karen Klonsky Louise Jackson Stephen B. Brush Sean Smukler 《Agroforestry Systems》2009,76(1):195-206
Although hedgerows, windbreaks, and other biodiversity-enhancing farm edge features offer the potential for ecosystem benefits
without occupying much crop space, relatively few farms in California, USA include such features. Our study identified the
practices currently used to manage non-cropped edges of fields, ponds, and watercourses in a case study area in California.
We also identified social, economic, and agronomic incentives and constraints to installing biodiversity-enhancing edge features.
More than one-third of the study farmers had installed native hedgerows, windbreaks, and/or grassed edges. Interviews demonstrated
the importance of socially influential farmers working in tandem with public and private agencies to build initial interest
in these practices. However, these features occupied less than four percent of all possible edge length. Constraints to increasing
adoption included high costs, fear of harbouring weeds and rodents, and lack of certainty about ecosystems benefits, highlighting
the need for cost-share programs and more regionally-focused agroecological research. 相似文献
212.
Mogens S. Hovmøller Karen E. Henriksen 《European journal of plant pathology / European Foundation for Plant Pathology》2008,121(3):377-385
The present paper presents the rationale for the use of pathogen surveys, inoculated and non-inoculated disease nurseries
and varietal resistance characteristics in an integrated approach to control wheat yellow rust in Denmark. The non-inoculated
disease observation plots, which gave valuable information about yellow rust at the year, site and variety level, served as
the primary sample source for the pathogen survey revealing pathogen virulence dynamics. This survey was also the main source
for isolates of new pathotypes, a prerequisite for the assessment of the resistance characteristics of varieties and breeding
lines in inoculated nurseries, and the postulation of race-specific resistance genes. A simple grouping of varieties into
four categories with respect to resistance to the current yellow rust population proved robust, and this grouping was used
as a determinant in a web-based decision support system for pesticide applications in cereals, Crop Protection On-line (CPO).
The interplay between the different research and survey activities in the integrated pest management (IPM) approach demonstrated
the need for a coherent and long-term involvement at all stages from plant breeding to the official variety approval system,
extension service and research in disease epidemiology and resistance genetics. 相似文献
213.
A comprehensive literature review was conducted to identify the magnitude of bird and rodent damage to 19 economically important crops in California. Interviews with agriculture experts provided additional information about damages. Monte Carlo simulations were used to derive summary estimates of damages to each crop. A meta-analysis indicated that summary damage estimates from expert interviews were higher than estimates from field studies and surveys. It was also found that there has been a downward trend over time in damages to almonds and grapes. The results of our study indicate that damages from bird and rodents remain high for many crops and are likely to be economically significant within the state of California. 相似文献
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217.
Shanon M. Zabolotzky Karen M. Vernau Philip H. Kass William Vernau 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2010,39(1):90-95
Background: Myelin‐like material in canine cerebrospinal fluid (CSF) specimens has been attributed to demyelinating or myelomalacic conditions. In our experience, myelin‐like material is observed frequently, especially in lumbar samples, and in a variety of disease conditions. Objectives: The objective of this study was to determine if there are associations between the presence of myelin‐like material and CSF collection site, body weight, underlying disease, and patient outcome. Methods: Wright–Giemsa‐stained cytocentrifuged specimens of CSF from the cerebellomedullary cistern (n=51) and lumbar cistern (n=47) of 98 dogs with neurologic disease were evaluated retrospectively for the presence and amount of extracellular myelin‐like material. Results were compared based on collection site, body weight, type of neurologic disease, and outcome. Results: Myelin‐like material was observed in 20/98 (20%) samples and was more frequently observed in lumbar (17/47, 36%) than cerebellomedullary samples (3/51, 6%) (P=.0028). Samples from dogs <10 kg were more likely to contain myelin (14/36, 39%) compared with dogs ≥10 kg (5/60, 8%) (P=.0052). Larger amounts of myelin‐like material were observed in CSF from dogs with intervertebral disk disease compared with other diseases (P=.045). No association was found between myelin‐like material and outcome. Conclusion: The association of extracellular myelin‐like material in canine CSF samples with sampling site and body weight suggests it is more often an artifact of collection technique and anatomy rather than the result of neurologic disease. Myelin‐like material in CSF is not associated with a poorer prognosis. 相似文献
218.
Mazepa AW Kidd LB Young KM Trepanier LA 《Journal of the American Animal Hospital Association》2010,46(6):405-412
Anaplasma (A.) phagocytophilum, the etiological agent of canine granulocytic anaplasmosis, is capable of inciting moderate to severe clinical disease in a variety of mammals and is endemic in the upper midwest. The purpose of this study was fourfold: to describe the range of clinical signs in dogs seropositive to A. phagocytophilum; to examine the prevalence of immune-mediated hemolytic anemia (IMHA) in this population; to evaluate whether specific clinical signs were associated with coexposure to Borrelia (B.) burgdorferi in actively infected dogs; and to determine whether clinical response to doxycycline was complete in treated dogs. Medical records of dogs seropositive for A. phagocytophilum were reviewed retrospectively. Peripheral blood smears were also reviewed retrospectively for granulocytic Anaplasma morulae. Lethargy (81%), inappetence (58%), and lameness (50%) were the most common clinical signs, followed by fever (46%). Thrombocytopenia was the most common laboratory abnormality, and IMHA was diagnosed in three dogs. Dogs that were thrombocytopenic and had antibodies to both A. phagocytophilum and B. burgdorferi had a median platelet count of 51,000/μL (range 20,000 to 171,000/μL), which was significantly lower than the count in dogs with antibodies only to A. phagocytophilum (P=0.04). Some dogs had an apparent relapse of clinical signs after an appropriate course of doxycycline. Testing for A. phagocytophilum by polymerase chain reaction, serum antibody assays, and/or blood smear evaluation should be considered in dogs with IMHA, cough, or epistaxis and that reside in A. phagocytophilum-endemic areas. If moderate to severe thrombocytopenia is present, testing for concurrent B. burgdorferi infection may be warranted. 相似文献
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In this study, 5/6 commercially available fungal culture media were comparable with respect to first growth, first colour change, and first sporulation when inoculated with three strains of Microsporum canis, one strain of Microsporum gypseum, and one strain of Trichophyton species when incubated at either 25°C or 30°C. Five of six plates showed 100% growth at both temperatures. Five of six plates showed 100% growth when inoculated with naturally infective M canis hairs and spores. One commercial product packaged as a self-sealing incubation plate showed growth in only 65.4% of times and the plates were prone to desiccation. M canis inoculated plates were incubated under four different light exposures (24h of light, 24h of dark, 12h light/12h dark, and room lighting) and no differences in growth or sporulation were noted. 相似文献