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71.
Alexander Rebl Tom Goldammer Uwe Fischer Bernd Kllner Hans-Martin Seyfert 《Veterinary immunology and immunopathology》2009,131(1-2):122-126
Toll-like receptors (TLR) are relevant for piscine innate immunity. TLR activation recruits several downstream factors regulating the expression of immunorelevant genes. We have characterized two key factors of innate immunity from rainbow trout: MyD88 as an adaptor protein interacting directly with TLRs, and serum amyloid A as an effector molecule induced by the activated Toll-like receptor signaling cascade.Both factors share a remarkable high degree of structural conservation with their mammalian orthologs suggesting that innate immune defense mechanisms may also functionally be conserved between fish and mammals. 相似文献
72.
Bernd Schneider Manfred Stock Horst R. Schütte Klaus Schreiber Johannes Kster Ernst U. Kaußmann 《Pest management science》1993,37(1):9-13
Significant radioactivity detected in mature fruits, harvested from apple trees (Malus domestica Borkh., cv. ‘Golden Delicious’ and ‘Gloster’) that were soiltreated with [3,5-14C]amitrole, remained in the insoluble plant material after exhaustive extraction. These bound residues were solubilized with a mixture of pectinases and cellulases. Thus, separation and characterization of carbohydrates and xenobiotic moieties released during this procedure became possible. A part of the radiolabel was incorporated into natural products, indicating degradation of the applied amitrole and reassimilation of [14C] carbon dioxide. 相似文献
73.
Bernd Schneider Manfred Stock Hartmut Bohm Gernot Schneider Horst-Robert Schütte Klaus Schreiber Angela Brauner Johannes Kster Ernst U. Kaußmann 《Pest management science》1994,41(4):327-333
Excised shoots from apple trees and cell suspension cultures were used as model systems to study the metabolism of [3,5-14C]amitrole in Malus domestica Borkh. Significant differences in the metabolism of the compound applied were observed with excised shoots, cultured cells and whole apple trees. The major metabolite in excised shoots was aminotriazolylalanine which occurred both in the free form and as conjugates. The major metabolite from whole plants. triazolylalanine, was detected in shoots in minor amounts only. In cell suspension cultures, the type of metabolism strongly depended on the concentration of amitrole when initially applied. At 10 ?3 m or lower, mainly aminotriazolylalanine was formed. Depending on the concentration of the active ingredient, this metabolite predominantly occurred in free form or as glycosides. At concentrations above 5 × 10?4 M a new metabolite, 3,5-dihydroxytriazole, was detected which was the only metabolite found at 5 × 10?3M. Significant amounts of nonmetabolized amitrole remained in the medium. 相似文献
74.
Gaede W Gehrmann B Körber R 《Berliner und Münchener tier?rztliche Wochenschrift》2003,116(5-6):234-239
With the long-term perspective of the eradication of BVD/MD in the German federal state Saxony-Anhalt a voluntary control program was initiated in 2002 by an administrative regulation based on federal German guidelines. The short-term aim of this program is the establishment of BVDV-unsuspected herds achieved by elimination of persistently infected cattle. The diagnostic program and particularly the choice of the diagnostic tools was based on the consideration of laboratory experiences as well as on economic and logistic aspects. A combination of RT-PCR and antigen-ELISA was found to be the suitable diagnostic methods. The screening started with examinations of sera pools using Real Time RT-PCR in the Light-Cylcer system. After positive pool results the individual persistently infected animals were detected using various commercial ERNS-antigen-ELISAs. The RT-PCR revealed a high degree of sensitivity and robustness. With respect to highly specific ELISAs the producers have to ensure the detection of all currently important virus strains. The prevalence of persistently infected animals in the cattle population of Saxony-Anhalt was about 0.2% during the last 3 years. This is probably due to nearly 10 years of broad vaccination and will prove advantageous for BVDV elimination. 相似文献
75.
Christian Hoffmann Irena Savric Grzegorz Jozefaciuk Mieczyslaw Hajnos Zofia Sokoowska Manfred Renger Bernd Marschner 《植物养料与土壤学杂志》2002,165(1):67-71
Heavy metal polluted soils from a recent and a former sewage farm were studied in a 2.5 years‐column experiment under various irrigation regimes and/or liming treatment. The copper (Cu), zinc (Zn), lead (Pb), and cadmium (Cd) concentrations in the soil and the leaching of these elements were studied. The amounts of the metals leached differed markedly between both soils, however, the effect of various irrigation treatments was less pronounced. The heavy metal content in the soil solid phase depended on the organic carbon content, however these dependencies differed for both soils as well as for particular metals. In lower soil horizons, the amount of heavy metals bound by unit mass of organic carbon was constant. It was assumed that the same amount of the heavy metals can be bound by the unit mass of the DOC. Under this assumption the amount of the DOC in the former sewage farm soil was in general too small to carry all heavy metals leached. Therefore leaching of their cationic forms has been postulated. The amount of the DOC in the present sewage farm soil could carry more heavy metals than these being leached. Therefore, an undersaturation of the DOC in heavy metals could occur in this soil.<?show $6#> 相似文献
76.
Samples of six Polish and three Korean soils were acidified and alkalized with elevated concentrations of hydrochloric acid or sodium hydroxide from 0.001 to 1 mol dm—3. The pore system of the studied soils was investigated using mercury intrusion (”︁macropores”) and water vapor adsorption (”︁mesopores”) experiments. The characteristics of the pores and their surfaces were very sensitive against acid and alkaline treatments. The macropore volume and radii increased in general with increasing of the concentrations of the treatment solutions. The macropore surface of all the clay rich soils exhibited a fractal behavior. The ranges of fractal scaling differed for particular soils. Macropore surface fractal dimensions changed under both treatments. For a given soil, the macropore fractal dimensions changed in the same direction under the effect of acid as under alkali. Both treatments decreased the mesopore volumes of Polish and increased the mesopore volumes of Korean soils. However, this was not true for two of Korean soils after extreme alkali treatments. In general, the average mesopore radius increased under lower treatments concentrations and decreased under higher concentrations. The mesopores were also fractal. The range of their fractal scaling was different for the Polish and Korean soils and roughly the same within each group. The fractal dimension of the mesopores decreased after acid treatment showing a smoothing of the material porous surface. Alkaline treatment affected the mesopore fractal dimension to a lower extent. A slight rise of the mesopore fractal dimension was noted in most cases.<?show $6#> 相似文献
77.
A map of soil texture profiles was derived from readily available spatial data in combination with information from soil profiles using CART (classification and regression trees). The primary purpose was to provide a regionalized predictor for the vertical hydraulic conductivity profiles to be used as an input variable to an evapo‐transpiration model. In contrast to former studies, the texture of 110 soil profiles taken in the 10 km2 area was not averaged vertically but the profiles were grouped according to their hydraulic properties. Therefore, it was possible to include site specific profiles, e.g. with histic or argillic horizons. Despite of small sampling quantities (110 soil profiles grouped into 8 classes) a prediction probability of 60 to 70 % was achieved in most classes. The resulting map provides valuable information for the granulometric and hydrologic characterization of the study area.<?show $6#> 相似文献
78.
79.
Thomas K. Gottschalk Tim Diekötter Klemens Ekschmitt Bernd Weinmann Friedrich Kuhlmann Tobias Purtauf Jens Dauber Volkmar Wolters 《Landscape Ecology》2007,22(5):643-656
Agricultural management is a major factor driving the change of faunal richness in anthropogenic landscapes. Thus, there is
an urgent need to develop tools that allow decision-makers to understand better intended and unintended effects of agricultural
policy measures on biodiversity. Here we demonstrate the potential of such a tool by combining a socio-economic model with
the biodiversity model GEPARD to forecast the response of bird and carabid species richness to two scenarios of agricultural
subsidies: (1) subsidies based on production levels and prices and (2) direct income support that is independent of production
levels. We focussed on farmland of the Lahn-Dill area, Germany, as an example of European regions with low intensity farming.
GEPARD predicts faunal richness and is based on multi-scaled resource-selection functions. Under both scenarios the area of
predicted losses in species richness of birds and carabids was larger than the area of predicted gains in species richness.
However, the area with predicted losses of avian richness was smaller under the direct income support scenario than under
the production-based subsidy scenario, whereas the area with predicted losses of carabid species richness was smaller under
the production-based subsidy scenario than under the direct income support. Yet locally, richness gains of up to four species
were predicted for carabids under both scenarios. We conclude that the sometimes contrasting and heterogeneous responses of
birds and carabids at different localities suggest the need for spatially targeted subsidy schemes. With the help of the GIS-based
approach presented in this study, prediction maps on potential changes in local and regional species richness can be easily
generated. 相似文献
80.
Wheat-barley translocations were identified by genomicin situ hybridization (GISH) in backcross progenies originating from in vitro regenerated wheat (Triticum aestivum L. cv. Chinese Spring) × barley (Hordeum vulgare L. cv. Betzes) hybrids. The regenerated hybrids were pollinated with the wheat line Martonvásári 9 kr1. Five translocated
wheat-barley chromosomes were recovered among 51 BC2F2 progeny from the in vitro regenerated wheat × barley hybrids. All were single breakpoint translocations with the relative positions of the breakpoints
ranging from the centromere to about 0.8 of the relative arm length. Of the four translocations with intercalary breakpoints,
three were transfers of terminal barley segments to wheat chromosomes; one was a transfer of a terminal wheat segment to a
barley chromosome. Because of the absence of diagnostic N-bands, the identity of three barley segments could not be determined;
in one translocation the barley chromosome involved had a NOR so it must have been 5H or 6H, and the centric translocation
was 4HS.2BL. Following selfing, homozygotes of four translocations were selected. The experiment suggests that in vitro culture conditions are conducive for major genome rearrangements in wheat-barley hybrids.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献