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1.
VJ Stenner 《Australian veterinary journal》2001,79(2):112-112
Manual of Canine and Feline Wound Management and Reconstruction. Edited by Fowler D and Williams JM 相似文献
2.
Ligia C Moreira Tiago L Passafaro Daniel M Schaefer Guilherme J M Rosa 《Journal of animal science》2021,99(1)
Cull dairy cows contribute almost 10% of national beef production in the United States. However, different factors throughout the life of dairy cows affect their weight and overall body condition as well as carcass traits, and consequently affect their market price. Therefore, the objectives of this study were: (1) to assess relationships between price ratio and carcass merit of cull dairy cows sold through several sites of an auction market and (2) to investigate the effect of animal life history events and live weight on sale barn price (BP) and price ratio (as a measure of relative price), as an indicator of carcass merit. Data from 4 dairy operations included 3,602 cull dairy cow records during the period of 2015 to 2019. Life history events data were collected from each dairy operation through Dairy Comp software; live weight and price were obtained periodically from the auction market, and the carcass data were provided by a local packing plant. Cow price in dollars per unit of live weight ($/cwt) and price ratio were the 2 outcome variables used in the analyses. Price ratio was created aiming to remove seasonality effects from BP (BP divided by the national average price for its respective month and year of sale). The association between price ratio and carcass merit traits was investigated using canonical correlation analysis, and the effect of life history events on both BP and price ratio was inferred using a multiple linear regression technique. More than 70% of the cows were culled in the first 3 lactations, with an average live weight of 701.5 kg, carcass weight of 325 kg, and dressing percentage of 46.3%. On average, cull cows were sold at $57.0/cwt during the period considered. The canonical correlation between price ratio and carcass merit traits was 0.76, indicating that price ratio reflected carcass merit of cull cows. Later lactations led to lower BP compared with cows culled during the first 2 lactations. Injury, and leg and feet problems negatively affected BP. Productive variables demonstrated that the greater milk production might lead to lower cow prices. A large variation between farms was also noted. In conclusion, price ratio was a good indicator of carcass merit of cull cows, and life history events significantly affected sale BP and carcass merit of cull cows sold through auction markets. 相似文献
3.
Waterlogging of field-grown plants can occur either when the surface of slowly permeable soils is inundated or when the water-table rises so that part or all of the root zone is saturated. The effects of short-term waterlogging on field crop growth and yield have not been well quantified. To study these effects, a sloping, repacked slab of soil underlain by an impermeable membrane was constructed. The sloping plot (45 m long × 6 m wide × 0.6 m deep) was flooded by introducing water through a drainage network and gravel bed so that a gradient of water-table depth ranging from 0.1 m above to 0.66 m below the soil surface was obtained. Cotton (Gossypium hirsutum cv. Deltapine 61) was grown in the facility and the responses of plants to two periods of flooding were monitored. Soil matric potential and oxygen partial pressure data indicated that plants were subjected to a continuum of conditions ranging from complete inundation to no water-table within the root zone.The first flooding event began 82 days after sowing just prior to the main flowering period. Plants with more than 55% of their root system below the water table showed decreased leaf growth about 3–4 days after the flooding started with visible wilt symptoms and decreased leaf water potential observed on days 7 and 8 of flooding. In the second flooding event (131 days after sowing), plants showed no signs of waterlogging stress apart from reduced leaf growth despite 16 days of flooding. Plant growth response was probably more the result of reduced nutrient status (mostly nitrate) rather than a water deficit stress effect with some plant acclimatization between the first and second flooding event. Seed cotton yield data indicated that the observed stress during the first flooding event may have promoted reproductive growth in plants where the short-term water-table was greater than 0.2 m below the soil surface. 相似文献
4.
Schaefer VJ 《Science (New York, N.Y.)》1941,93(2410):239-240
5.
The distribution of 17 dominant gall-inducing arthropods and 12 leaf miners on woody plants was analysed in the city of Kiel and surrounding habitats. The number of species and the diversity of the fauna in the two landscapes did not differ very much.Pemphigus bursarius, Schizoneura ulmi undStigmella argentipedella preferred trees in the city. In the city predominated plant parasites that hibernate on their host plant, while species overwintering in the litter on the ground or in the soil were suppressed. Important habitat factors may be mechanical perturbations near the ground (removal of leaf litter, pavement on the ground, trampling, digging of the soil). The number of species declined with decreasing size of the habitat islands (wood — bushes, hedges — individually growing trees or groups of trees on grassland — road trees), the species hibernating in the vegetation layer were favoured. 相似文献
6.
Natalha Biondo Rejane Schaefer Danielle Gava Mauricio E. Cantão Simone Silveira Marcos A.Z. Mores Janice R. Ciacci-Zanella David E.S.N. Barcellos 《Veterinary microbiology》2014
Influenza is a viral disease that affects human and several animal species. In Brazil, H1N1, H3N2 and 2009 pandemic H1N1 A(H1N1)pdm09 influenza A viruses (IAV) circulate in domestic swine herds. Wild boars are also susceptible to IAV infection but in Brazil until this moment there are no reports of IAV infection in wild boars or in captive wild boars populations. Herein the occurrence of IAV in captive wild boars with the presence of lung consolidation lesions during slaughter was investigated. Lung samples were screened by RT-PCR for IAV detection. IAV positive samples were further analyzed by quantitative real-time PCR (qRRT-PCR), virus isolation, genomic sequencing, histopathology and immunohistochemistry (IHC). Eleven out of 60 lungs (18.3%) were positive for IAV by RT-PCR and seven out of the eleven were also positive for A(H1N1)pdm09 by qRRT-PCR. Chronic diffuse bronchopneumonia was observed in all samples and IHC analysis was negative for influenza A antigen. Full genes segments of H1N2 IAV were sequenced using Illumina's genome analyzer platform (MiSeq). The genomic analysis revealed that the HA and NA genes clustered with IAVs of the human lineage and the six internal genes were derived from the H1N1pdm09 IAV. This is the first report of a reassortant human-like H1N2 influenza virus infection in captive wild boars in Brazil and indicates the need to monitor IAV evolution in Suidae populations. 相似文献
7.
Opportunities and Challenges of Carbon Footprint,Climate or CO2 Labelling for Horticultural Products
The number of fruits on the German and European markets with a carbon label is on the increase. This contribution reviews the existing carbon labels by evaluating, categorising and giving background information to provide guidance for labelling home-grown horticultural produce. The existing labels worldwide were classified in 10 categories: (1) CO2 value; (2) Colour code (with or without CO2 value); (3) CO2 reduction (Carbon Trust, Tesco’s, UK) or conversion labels; (4) Climatop for Migros, Switzerland (temporal label for the best product within a product category, e.g., banana, rice, salt); (5) Airfreight labels, e.g., Marks & Spencer’s UK (without further information); (6) ‘Climate, carbon offset or CO2-neutral’, e.g., NewTree, (only when using gold standard CO2 emission certificates); (7) unaccounted CO2 compensation measures (such as planting young trees: ‘CO2 pineapple’ in Costa Rica); (8) Sustainability labels (ProPlanet, REWE), (9) sustainability reports (printed or online) and (10) QR-Code on the shelf or product to access web-based information. The ‘Pros and Cons’ of the climate labels are compared with respect to the seasonal fruit and vegetables often sold on the markets as lose items and the stakeholder interest. Labelling approaches 4, 8, 9 and 10 appeared suitable for seasonal fruits and vegetables based on criteria such as transparency, clarity, objectivity and integration in the sustainability context. Overall, it is difficult to use labels with a CO2 value for horticultural products, because (a) the consumer may find it difficult to judge and memorise numeric values, particularly if expressed on different units (e.g. packet size, 1 l, 100 g) and (b) because of the big variation between the farm production systems and the variability between the year to year weather and (c) the consumer may find shopping with a seasonal crop calendar and country of origin label a better choice. 相似文献
8.
Ground-layer vegetation was sampled along selected trail corridors to determine whether corridors provide habitat for certain species and act as conduits for species movement. Patterns of plant species composition were analyzed in relation to distance from trail edge, level of trail use, and distance from trailheads, junctions, and campgrounds. Species composition was significantly affected by distance from trail edge and level of trail use, as species were favored or inhibited by the corridor, depending upon their growth habits. Species composition was also affected by distance from trailheads. These findings, along with the presence of exotic species, indicate that trail corridors in Rocky Mountain National Park function as habitat and conduits for movement of plant species. 相似文献
9.
A total of 31 isolates of Haemophilus parasuis obtained from Australian pigs were serotyped by the Kielstein-Rapp-Gabrielson scheme. The isolates were assigned to serovar 1 (1 isolate), serovar 2 (1 isolate), serovar 4 (4 isolates), serovar 5 (7 isolates), serovar 9 (2 isolates), serovar 10/7 (4 isolates), serovar 12 (1 isolate) and serovar 13 (6 isolates). The remaining 5 isolates could not be assigned to a serovar. Two different serovars (5 and 13) were detected in one herd. The only 2 isolates obtained from clinically normal pigs (from the same herd) were serovar 9. The common serovars were isolated from pigs with pneumonia as well as from pigs with conditions of the Glässer's disease type. The serological heterogeneity amongst Australian isolates of H parasuis has important implications for the use of vaccines to control Glässer's disease. 相似文献
10.
We used ionic tracers to estimate the volume of old (soil and ground) water interacting with snowmelt in eleven Adirondack, NY watersheds. The contribution of old water varied from 66 to 90%, with no general relationship between old water % and soil depth to till. This approach also discriminated between watershed retention and release of particular ions to lake outlet water during snowmelt. Most watersheds released NO3 ? during snowmelt, in addition to the snowpack NO3 ?. Nitrification of snowpack NH4 + explained part of the additional NO3 ? in lake out outlet water, but some NO3 ? was likely mineralized nitrogen from soil organic matter. All watersheds retained NH4 + as well. Nitrogen release was greatest in the acidic watersheds in the southwestern Adirondacks, a region thought to be impacted by anthropogenic deposition. During snowmelt, Ca2+ and Mg2+ ions (presumably from soil exchange sites) were also released from most watersheds. In watersheds with acidic (minimum pH<4.6) lake outlet water, Al was also released during snowmelt. Thus, lake outlet water acidification during snowmelt was both buffered by cation release, and intensified by NO3 ? release. If the soil exchangeable cation pools were not replenished prior to snowmelt, or NO3 ? mobilization were increased, acidification during snowmelt would intensify. 相似文献