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101.
Ruth Müller Cornelia Bandow Anne Seeland Dennis Fennel Anja Coors Peter K. Ebke Bernhard Förster Pedro Martinez-Arbizu Thomas Moser Matthias Oetken Jasmin Renz Jörg Römbke Nadine Schulz Jörg Oehlmann 《Journal of Soils and Sediments》2010,10(4):718-721
Introduction
How will the combination of climate-induced physical/chemical changes and anthropogenic pollution impact key species and biodiversity, and thus the ecosystem functions in future?Discussion
The project AdaMus within the newly founded Biodiversity and Climate Research Centre BiKF aims to understand the prospective ecosystem stress responses and adaptive potential of species and communities to multiple stressors to provide reliable predictions of future developments in terrestric, aquatic and marine environments.Conclusion
Long-term experiments with terrestrial, aquatic and marine species and communities will be conducted under IPCC predicted climate conditions. In terrestric and limnic experiments, additional co-stressors such as pesticides and alien species are introduced to test for interactions. In the case of marine plankton, potential consequences of multiple climate-related changes in the physical environment (temperature, salinity and oxygen) will be analysed. 相似文献102.
Ursprung J Joachim A Prosl H 《Berliner und Münchener tier?rztliche Wochenschrift》2006,119(7-8):316-323
Fascioloides magna,the giant liver fluke, is an introduced parasite imported to Europe with infected game which is endemic in the Austrian wetlands of the Danube from Vienna to the Slovakian border. Due to its pathogenicity (especially in roe deer) and its potential of transmission to domestic ruminants a project on the epidemiology and control of this parasite was carried out between 2000 and 2005. To assess distribution faecal droppings from red deer were collected in an area along the Danube and livers of red and roe deer shot or found dead were examined. Simultaneously, triclabendazole-medicated feed was offered repeatedly in several areas of known fluke presence from 2001. The average prevalence of infection as demonstrated by Fascioloides eggs in droppings (n = 145) was 6.3%, with > 50% in some areas. Infection rates decreased from 11.3% (01/2001) to 1.5% (04/2002) in the whole area. In Fischamend, a highly endemic area, prevalences in monthly samples (n = 25) decreased from 70% (01/2001) to less than 1% (01/2005). Similarly, the number of eggs per gram of faeces was significantly reduced. Of 457 red deer livers 15.8% were positive. In the Fischamend area, a reduction of positive livers was also found (2000:100%; 2005:13%), as well as a reduction of the numbers of flukes/liver. Control of F. magna in the Danubian wetlands by anthelmintic treatment proved to be successful although eradication was not achieved. 相似文献
103.
104.
Influence of thaxtomins in different combinations and concentrations on growth of micropropagated potato shoot cultures 总被引:1,自引:0,他引:1
Hiltunen LH Laakso I Chobot V Hakala KS Weckman A Valkonen JP 《Journal of agricultural and food chemistry》2006,54(9):3372-3379
Plant-pathogenic Streptomyces species produce a variety of different phytotoxic 4-nitroindol-3-yl-containing 2,5-dioxopiperazines (thaxtomins) that induce scab symptoms on potato tubers (Solanum tuberosum). The possible mutual synergistic or antagonistic effects of thaxtomins are unknown. Modified methodology using column chromatography allowed the purification of thaxtomin A in large quantities (27 mg, HPLC purity of 97%). Thaxtomin A ortho isomer, thaxtomin B, and C-14 deoxythaxtomin B (thaxtomin D) were also purified. All four compounds induced similar symptoms of reduced root and shoot growth, root swelling (10-200 ppb), or necrosis (200-1000 ppb) on micropropagated in vitro cultures of potato. The scab-resistant potato cvs. Sabina and Nicola were more tolerant to thaxtomins than was the scab-susceptible cv. Matilda. Thaxtomins applied in combinations showed additive effects but no synergism, whereas thaxtomins A and B displayed antagonism with thaxtomin A ortho isomer. 相似文献
105.
106.
Bonilla WV Fröhlich A Senn K Kallert S Fernandez M Johnson S Kreutzfeldt M Hegazy AN Schrick C Fallon PG Klemenz R Nakae S Adler H Merkler D Löhning M Pinschewer DD 《Science (New York, N.Y.)》2012,335(6071):984-989
Pathogen-associated molecular patterns decisively influence antiviral immune responses, whereas the contribution of endogenous signals of tissue damage, also known as damage-associated molecular patterns or alarmins, remains ill defined. We show that interleukin-33 (IL-33), an alarmin released from necrotic cells, is necessary for potent CD8(+) T cell (CTL) responses to replicating, prototypic RNA and DNA viruses in mice. IL-33 signaled through its receptor on activated CTLs, enhanced clonal expansion in a CTL-intrinsic fashion, determined plurifunctional effector cell differentiation, and was necessary for virus control. Moreover, recombinant IL-33 augmented vaccine-induced CTL responses. Radio-resistant cells of the splenic T cell zone produced IL-33, and efficient CTL responses required IL-33 from radio-resistant cells but not from hematopoietic cells. Thus, alarmin release by radio-resistant cells orchestrates protective antiviral CTL responses. 相似文献
107.
Constructed wetlands for the treatment of organic pollutants 总被引:2,自引:1,他引:2
Raimund Haberl Stefano Grego Günter Langergraber Robert H. Kadlec Anna-Rita Cicalini Susete Martins Dias Julio M. Novais Sylvie Aubert Andre Gerth Hartmut Thomas Anja Hebner 《Journal of Soils and Sediments》2003,3(2):109-124
Background Constructed wetlands (wetland treatment systems) are wetlands designed to improve water quality. They use the same processes
that occur in natural wetlands but have the flexibility of being constructed. As in natural wetlands vegetation, soil and
hydrology are the major components. Different soil types and plant species are used in constructed wetlands. Regarding hydrology
surface flow and subsurface flow constructed wetlands are the main types. Subsurface flow constructed wetlands are further
subdivided into horizontal or vertical flow. Many constructed wetlands deal with domestic wastewater where BOD and COD (Biochemical
and Chemical Oxygen Demand respectively) are used as a sum parameter for organic matter. However, also special organic compounds
can be removed.
Objective The objectives are to summarise the state-of-the-art on constructed wetlands for treatment of specific organic compounds,
to the present the lack of knowledge, and to derive future research needs.
Methods Case studies in combination with a literature review are used to summarise the available knowledge on removal processes for
specific organic compounds.
Results and Discussion Case studies are presented for the treatment of wastewaters contaminated with aromatic organic compounds, and sulphonated
anthraquinones, olive mill wastewater, landfill leachate, and groundwater contaminated with hydrocarbons, cyanides, chlorinated
volatile organics, and explosives. In general the removal efficiency for organic contaminants is high in all presented studies.
Conclusion Constructed wetlands are an effective and low cost way to treat water polluted with organic compounds. There is a lack of
knowledge on the detailed removal pathways for most of the contaminants. Removal rates as well as optimal plant species are
substance-specific, and also typically not available. If a constructed wetland provides different environmental conditions
and uses different plant species the treatment efficiency can be improved.
Recommendations and Outlook There is a great need to lighten the black box ‘constructed wetland’ to obtain performance data for both microbial activity
and the contribution of the plants to the overall removal process. Also genetic modified plants should be considered to enhance
the treatment performance of constructed wetlands for specific compounds. 相似文献
108.
To study the formation of fumonisin artifacts and the binding of fumonisins to matrix components (e.g., saccharides and proteins) in thermal-treated food, model experiments were performed. Fumonisin B(1) and hydrolyzed fumonisin B(1) were incubated with alpha-d-glucose and sucrose (mono- and disaccharide models), with methyl alpha-d-glucopyranoside (starch model), and with the amino acid derivatives N-alpha-acetyl-l-lysine methyl ester and BOC-l-cysteine methyl ester (protein models). The reaction products formed were analyzed by liquid chromatography-electrospray ionization-tandem mass spectrometry. The incubation of d-glucose with fumonisin B(1) or hydrolyzed fumonisin B(1) resulted in the formation of Amadori rearrangement products. Whereas conjugates were found following the reaction of sucrose, methyl alpha-d-glucopyranoside, and the amino acid derivatives with fumonisin B(1), the heating with hydrolyzed fumonisin B(1) yielded no artifacts. For structural determination, the stable reaction product formed by heating of methyl alpha-d-glucopyranoside (as starch model) with fumonisin B(1) was purified and identified by nuclear magnetic resonance spectroscopy as the diester of the fumonisin tricarballylic acid side chains with methyl alpha-d-glucopyranoside. These model experiments demonstrate that fumonisins are able to bind to polysaccharides and proteins via their two tricarballylic acid side chains. 相似文献
109.
Eliane Marti Ella N. Novotny Iva Cvitas Anja Ziegler A. Douglas Wilson Sigurbjörg Torsteinsdottir Antonia Fettelschoss-Gabriel Sigridur Jonsdottir 《Veterinary dermatology》2021,32(6):579-e156
Culicoides hypersensitivity (CH) is a strongly pruritic dermatitis of horses, characterised histologically by mixed perivascular to diffuse cellular infiltrates of mononuclear cells and eosinophils, and caused by helper T cell (Th)2, immunoglobulin (Ig)E-mediated reactions to antigens present in the saliva of biting Culicoides midges. As treatment of CH is still not satisfactory, a better knowledge of the pathogenesis of CH is needed for the development of new therapeutic modalities. Accordingly, availability of pure Culicoides allergens instead of crude whole body extracts is essential for the improvement of in vitro diagnosis of CH and development of a more effective allergen immunotherapy (AIT). Beside the Th2 cytokines interleukin (IL)-4 and IL-13, recent studies have shown the involvement of thymic stromal lymphopoietin, IL-5 and IL-31 in the pathogenesis of CH. The importance of IL-5 and IL-31 has been confirmed through targeting these cytokines by active immunisation of CH patients, resulting in a significant decrease of CH lesion scores. Thirty Culicoides salivary allergens have been described over the last 10 years and produced as pure recombinant (r-) proteins. Use of a protein microarray has allowed the identification of the most relevant Culicoides r-allergens for CH in central and northern Europe. An immunisation protocol has been developed for preventive AIT against CH. Small amounts of r-Culicoides allergens injected into the submandibular lymph nodes with Alum/MPLA as adjuvants seem to induce a suitable immune response for both preventive and therapeutic AIT. The next years will reveal whether these recent advancements will translate into an improved diagnosis, treatment and prevention of CH. 相似文献
110.
Jessica Schmäck Lutz Weihermüller Anja Klotzsche Christian von Hebel Stefan Pätzold Gerhard Welp Harry Vereecken 《Soil Use and Management》2022,38(1):212-228
Fast and accurate large-scale localization and quantification of harmfully compacted soils in recultivated post-mining landscapes are of particular importance for mining companies and the following farmers. The use of heavy machinery during recultivation imposes soil stress and can cause irreversible subsoil compaction limiting crop growth in the long term. To overcome or guide classical point-scale methods to determine compaction, fast methods covering large areas are required. In our study, a recultivated field of the Garzweiler mine in North Rhine-Westphalia, Germany, with known variability in crop performance was intensively studied using non-invasive electromagnetic induction (EMI) and electrode-based electrical resistivity tomography (ERT). Additionally, soil bulk density, volumetric soil water content and soil textures were analysed along two transects covering different compaction levels. The results showed that the measured EMI apparent electrical conductivity (ECa) along the transects was highly correlated (R2 > .7 for different dates and depths below 0.3 m) to subsoil bulk density. Finally, the correlations established along the transects were used to predict harmful subsoil compaction within the field, whereby a spatial probabilistic map of zones of harmful compaction was developed. In general, the results revealed the feasibility of using the EMI derived ECa to predict harmful compaction. They can be the basis for quick monitoring of the recultivation process and implementation of necessary melioration to return a well-structured soil with good water and nutrient accessibility, and rooting depths for increased crop yields to the farmers. 相似文献