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991.
Journal of Plant Diseases and Protection - In Gewächshausversuchen mit der Ro1-anfälligen Tomatensorte ‘Harzfeuer’ und der Ro1-resistenten Tomatensorte ‘Sparta’... 相似文献
992.
Captan, a major fungicide used by the US maize industry, was studied to determine its effect on the nuclear DNA content of maize (Zea mays L.) seedlings. Captan was applied to kernels at the recommended agronomic rates. The nuclear DNA content of the seedlings was determined by flow cytometry. In two maize hybrids examined, a reduction in nuclear DNA content was observed. Two different fluorochromes, with different staining mechanisms, were used to determine nuclear DNA content. Both of these fluorochromes revealed a reduction in nuclear DNA. Captan is reported to inhibit DNA synthesis in several animal systems. The reduction of maize nuclear DNA observed in this study may be a result of DNA synthesis inhibition induced by captan. 相似文献
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Marco ROELCKE Lisa HEIMANN Yong HOU Jianbin GUO Qiaoyun XUE Wei JIA Anne OSTERMANN Roxana Mendoza HUAITALLA Moritz ENGBERS Clemens OLBRICH Roland W. SCHOLZ Joachim CLEMENS Frank SCHUCHARDT Rolf NIEDER Xuejun LIU Fusuo ZHANG 《农业科学与工程前沿(英文版)》2019,6(4):388
The Sino-German research collaboration project, “Recycling of organic residues from agricultural and municipal origin in China” (2008–2012), comprising different interdisciplinary research groups, and also German small and medium-sized enterprises, aimed at developing integrated strategies and solutions for the recycling of organic residues in China. In an intensive crop-livestock agricultural region in the Shunyi District of Beijing, five typical cropping systems were investigated. The research was conducted in the form of analyses of phosphorus (P) in soil, plants, animal feed, animal products, manures, mineral and organic fertilizers and the derivation of the corresponding nutrient balances and P flows. The mean annual P balance surplus was 492 kg·ha−1·yr−1 P for the vegetable production system, significantly higher (P<0.05) than that for orchards (130 kg·ha−1·yr−1P) and cereal crops (83 kg·ha−1·yr−1 P). Plant-available P (Olsen-P) concentrations of topsoils (0–20 cm) had good correlations with the amounts of P applied (from mineral and organic sources). Compared to results from the Second Chinese National Soil Survey of 1981, mean concentrations of available P in soils of 19 plots investigated in Shunyi District increased 10-fold (from 7.3 to 60 mg·kg−1) from 1981 to 2009. On average, the critical limit for Olsen-P concentrations (>30 mg·kg−1) that can lead to increased risk of P loss was exceeded in all five cropping systems. With feed additives, the “natural background value” (Chinese Environmental Quality Standard for Soils) of copper and zinc in topsoils was exceeded at several sites. Screening for several substances in the veterinary antibiotic classes of sulfonamides, tetracyclines, and fluoroquinolones revealed widespread topsoil contamination. Calculated livestock densities were 10.6 livestock units per ha arable land in 2007. Animal husbandry is increasingly conducted in large operations, making traditional ways of reuse difficult to apply. Comparing three management systems for treatment of organic residues from a pig farm via aerobic (composting) or anaerobic (biogas) treatment in a life cycle assessment, the resulting cropland demand for a sustainable land application of biogas effluent varied between 139 and 288 ha·yr−1, well above the cropland area owned by the farm (10 ha). The mismatch problems in the above context between business-as-usual and improving performance are framed and discussed as (1) the mismatch between centralized animal husbandry and smallholder farming, (2) the mismatch between livestock density and cropland, (3) nutrient (including P) recycling and increasing organic matter content versus energy production, (4) subsidies for compost production and biogas, as well as (5) advances in the regulatory framework in China. 相似文献
996.
本文以美国农业部的报告为依据,分析了生产第二代燃料进展缓慢的原因,研制生产第二代燃料的具体情况及目前所面临的问题、挑战,并简要介绍了欧盟生产第二代燃料的情况。 相似文献
997.
Sara A. Berges Lisa A. Schulte Moore Thomas M. Isenhart Richard C. Schultz 《Agroforestry Systems》2010,79(1):97-110
In response to concern about the loss of ecosystem services once provided by natural riparian systems, state and federal agencies
have established incentive programs for landowners to convert sensitive lands from agricultural to conservation uses. Enhancement
of wildlife habitat, while identified as a function of such systems, has often been of secondary importance to soil conservation
and water quality objectives. Though greatly important, little consideration has been given to how specific species will respond
to the design and management of riparian buffers or other conservation lands. This study compared avian communities within
a chronosequence of riparian buffers established on previously cropped or pastured land with those of the nearby matrix land
cover types (row crop fields and an intensively grazed pasture). The riparian buffers consisted of native grasses, forbs,
and woody vegetation established at three different times (2, 9, and 14+ years prior to survey). At each site, 10 min point
counts for breeding birds were conducted using 50 m fixed radius plots, which were visited eight times between May 15 and
July 10, 2008. A total of 54 bird species were observed over all of the study sites. The re-established riparian buffers in
this study had higher bird abundance, richness, and diversity than the crop and pasture sites. These results suggest that
re-establishing native riparian vegetation in areas of intensive agriculture will provide habitat for a broad suite of bird
species, but that specific species will reflect successional stage, horizontal and vertical vegetative structure, and compositional
diversity of the buffer vegetation. These results emphasize the importance of matching buffer design and management to species
requirements if the objectives are to attract specific target species or species groups. 相似文献
998.
Fuel treatments alter conditions in forested stands at the time of the treatment and subsequently. Fuel treatments reduce on-site carbon and also change the fire potential and expected outcome of future wildfires, including their carbon emissions. We simulated effects of fuel treatments on 140 stands representing seven major habitat type groups of the northern Rocky Mountains using the Fire and Fuels Extension to the Forest Vegetation Simulator (FFE-FVS). Changes in forest carbon due to mechanical fuel treatment (thinning from below to reduce ladder fuels) and prescribed fire were explored, as well as changes in expected fire behavior and effects of subsequent wildfire. Results indicated that fuel treatments decreased fire severity and crown fire occurrence and reduced subsequent wildfire emissions, but did not increase post-wildfire carbon stored on-site. Conversely, untreated stands had greater wildfire emissions but stored more carbon. 相似文献
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1000.
Chiara Lanzanova Maria Gabriella Giuffrida Mario Motto Cristina Baro Guenter Donn Hans Hartings Elisabetta Lupotto Maria Careri Lisa Elviri Carlotta Balconi 《European journal of plant pathology / European Foundation for Plant Pathology》2009,124(3):471-482
In maize endosperm, a cytosolic albumin, b-32, with a molecular weight of 32 kDa is synthesised in temporal and quantitative
coordination with the deposition of storage proteins. This protein has homology with several previously characterised Ribosome-Inactivating
Proteins (RIPs). To verify if the maize plant expressing b-32 in various tissues has an increased tolerance to fungal pathogens,
transgenic plants were obtained through genetic transformation using a chimeric gene containing the b-32 coding sequence downstream of a constitutive 35SCaMV promoter. A set of four independent homozygous progenies expressing b-32, were selected for a detailed analysis of b-32 expression
in leaves and for pathogenicity tests. A differential b-32 content in leaf protein extracts was recorded in the transgenic
progenies. Proteomic investigations on protein leaf extracts were carried out; the overlapping of the two-dimensional electrophoresis
maps demonstrated the presence in a transgenic progeny, of additional spots, identified as b-32 and as a protein for herbicide
resistance, in comparison to the negative control. Transgenic progenies were tested in bioassays to evaluate the response
to Fusarium attack in leaf tissues. Preliminary experiments supported the choice of bioassay parameters for a reliable evaluation
of transgenic progenies. The negative control was most susceptible to Fusarium verticillioides attack, compared to transgenic progenies. The data obtained indicate that maize b-32 was an effective antifungal protein
by reducing Fusarium infection progression. Additionally, the reduction in Fusarium attack symptoms was related to b-32 concentration
in leaf tissues. 相似文献