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101.
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The transmission of bovine viral diarrhea virus (BVDV) from persistently infected (PI) heifers to adult seronegative goats was examined in this study. Ten seronegative adult goats were exposed to 4 PI heifers. None of the goats developed any clinical signs but all goats seroconverted by 42 days after exposure to the PI cattle. Results indicate that goats are susceptible to BVDV infection when housed with PI cattle.  相似文献   
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Lymphocytic Thyroiditis in the Dog   总被引:1,自引:0,他引:1  
Abstract— —A 0.4 per cent incidence of lymphocytic thyroiditis was seen in 4,500 dogs examined. The haematological and biochemical investigations failed to reveal any results of diagnostic significance. The histological features were reminiscent of a human Hashimoto's disease. Whilst the condition was similar to that seen in man, several significant differences were noted. A genetically linked auto-immune aetiology was considered the most likely.
Résumé— —La morbidité de la thyroïdite lymphocytaire constatée au cours de l'examen de 4.500 chiens atteignait 0,4 pour cent. Les examens hématologiques et biochimiques n'ont donné aucun résultat d'intérêt diagnostique. Les caractéristiques histologiques constatées évoquaient la maladie de Hashimoto chez I'homme. L'état des chiens étudiés ressemblait en principe à la maladie rencontrée chez I'homme, mais plusieurs différences ont été nottés. Il y a lieu de croire à une auto-immunitéà corrélation génétique.
Zusammenfassung— —Bei 4500 untersuchten Hunden wurde lymphocytische Thyreoiditis mit einer Häufigkeit von 0,4% beobachtet. Die hämatologischen und biochemischen Untersuchungen lieferten keine Ergebnisse von diagnostischer Bedeutung. Die histologischen Besonderheiten erinner-ten an die Hashimotosche Krankheit des Menschen. Obwohl der Zustand dem beim Menschen auftretenden glich, wurden doch mehrere Unterschiede bemerkt. Eine genetisch bedingte autoimmune Ätiologie wurde für am wahrscheinlichsten gehalten.  相似文献   
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The advent of affordable, ground-based, global positioning information (GPS)–enabled sensor technologies provides a new method to rapidly acquire georeferenced soil datasets in situ for high-resolution soil attribute mapping. Our research deployed vehicle-mounted electromagnetic sensor survey equipment to map and quantify soil variability (?50 ha per day) using apparent electrical conductivity as an indirect measure of soil texture and moisture differences. A portable visible–near infrared (VNIR) spectrometer (350–2500 nm) was then used in the field to acquire hyperspectral data from the side of soil cores to a specified depth at optimized sampling locations. The sampling locations were derived by statistical analysis of the electromagnetic survey dataset, to proportionally sample the full range of spatial variability. The VNIR spectra were used to predict soil organic carbon (prediction model using field-moist spectra: R2 = 0.39; RPD = 1.28; and air-dry spectra: R2 = 0.80; RPD = 2.25). These point values were combined with the electromagnetic survey data to produce a soil organic carbon map, using a random forest data mining approach (validation model: R2 = 0.52; RMSE = 3.21 Mg C/ha to 30 cm soil depth; prediction model: R2 = 0.92; RMSE = 1.53 Mg C/ha to 30 cm soil depth). This spatial modeling method, using high-resolution sensor data, enables prediction of soil carbon stocks, and their spatial variability, at a resolution previously impractical using a solely laboratory-based approach.  相似文献   
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Some legume species of the Crotalaria genus are specifically nodulated by methylotrophic bacteria belonging to the Methylobacterium nodulans species. The feature of this symbiotic bacterium is its ability to oxidize methanol, a property based on the presence of a methanol dehydrogenase enzyme. Despite a good knowledge of this property and its implication in symbiosis, the molecular dialogue between M. nodulans and crotalaria podocarpa leading to symbiosis is largely unknown, except the presence of a nodA nodulation gene in the genome of M. nodulans ORS 2060. To investigate if M. nodulans ORS 2060 produces Nod factors, molecules considered as the major bacteria-to-plant signals essential for the establishment of rhizobia–legume symbiosis, we identified and sequenced a nodDABCUIJHQ cluster from a genomic library of ORS 2060. Phylogenetic analyses of nod genes revealed that M. nodulans ORS 2060 form a branch together with Burkholderia tuberum STM678 and a strain of Methylobacterium sp. (4-46) isolated from Lotononis, and distinct from all the other rhizobia. To analyse the regulation of ORS 2060 nod genes, we constructed a nodA–LacZ promoter fusion to monitor the nod gene expression with various flavonoids. The flavone apigenin was found to be the strongest inducer of nod gene expression in M. nodulans ORS 2060. This latter flavonoid was used to induce ORS 2060, and Nod factors were purified by high-performance liquid chromatography (HPLC) and further characterized by mass spectrometry. One major Nod factor structure was identified as a pentamer of chitin substituted by C18:1 or C16:0 acyl chains on the non-reducing end and 6-O-sulphated on the other end, suggesting a classic symbiotic dialogue between M. nodulans and C. podocarpa.  相似文献   
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Tolerance to manganese toxicity in lucerne, assessed from four different seedling criteria in the selfed and crossed progenies of 4 parents, gave high heritability, as estimated from a parent-progeny regression analysis, interpreted under the assumption of autotetraploid inheritance. Genes controlling this character were therefore assumed to be additive and to have low or no dominance, thus increasing the effectiveness of selection.
Samenvatting Tolerantie tegen mangaanvergiftiging bij lucerne, bepaald met behulp van 4 criteria in nakomelingschappen verkregen door zelfbestuiving en kruisbestuiving van 4 ouders, vertoonden een hoge graad van erfelijkheid. Dit werd vastgesteld met behulp van een regressie-analyse der nakomelingschappen, geïnterpreteerd op basis van autotetraploide overerving.Verondersteld werd dat de erffactoren voor deze eigenschap een additieve werking hebben en een geringe of geen dominantie vertonen, zodat daardoor het effect van selectie gunstig wordt.
  相似文献   
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Suzanne Higgins  Saskia D. Keesstra  Žydrė Kadziuliene  Lionel Jordan-Meille  David Wall  Alessandra Trinchera  Heide Spiegel  Taru Sandén  Andreas Baumgarten  Johannes L. Jensen  Juliane Hirte  Frank Liebisch  Susanne Klages  Philipp Löw  Katrin Kuka  Maarten De Boever  Karoline D'Haene  Sevinc Madenoglu  Hesna Özcan  Wieke Vervuurt  Janjo de Haan  Willem van Geel  Bo Stenberg  Pascal Denoroy  Rok Mihelič  Alar Astover  Raquel Mano  Cristina Sempiterno  Fatima Calouro  Giuseppe Valboa  Helena Aronsson  Tore Krogstad  Stanislav Torma  Jose Gabriel  Peter Laszlo  Nils Borchard  Bartosz Adamczyk  Anna Jacobs  Beata Jurga  Bożena Smreczak  Bruno Huyghebaert  Morgan Abras  Raimonds Kasparinskis  Eloise Mason  Claire Chenu 《European Journal of Soil Science》2023,74(5):e13422
The European Commission has set targets for a reduction in nutrient losses by at least 50% and a reduction in fertiliser use by at least 20% by 2030 while ensuring no deterioration in soil fertility. Within the mandate of the European Joint Programme EJP Soil ‘Towards climate-smart sustainable management of agricultural soils’, the objective of this study was to assess current fertilisation practices across Europe and discuss the potential for harmonisation of fertilisation methodologies as a strategy to reduce nutrient loss and overall fertiliser use. A stocktake study of current methods of delivering fertilisation advice took place across 23 European countries. The stocktake was in the form of a questionnaire, comprising 46 questions. Information was gathered on a large range of factors, including soil analysis methods, along with soil, crop and climatic factors taken into consideration within fertilisation calculations. The questionnaire was completed by experts, who are involved in compiling fertilisation recommendations within their country. Substantial differences exist in the content, format and delivery of fertilisation guidelines across Europe. The barriers, constraints and potential benefits of a harmonised approach to fertilisation across Europe are discussed. The general consensus from all participating countries was that harmonisation of fertilisation guidelines should be increased, but it was unclear in what format this could be achieved. Shared learning in the delivery and format of fertilisation guidelines and mechanisms to adhere to environmental legislation were viewed as being beneficial. However, it would be very difficult, if not impossible, to harmonise all soil test data and fertilisation methodologies at EU level due to diverse soil types and agro-ecosystem influences. Nevertheless, increased future collaboration, especially between neighbouring countries within the same environmental zone, was seen as potentially very beneficial. This study is unique in providing current detail on fertilisation practices across European countries in a side-by-side comparison. The gathered data can provide a baseline for the development of scientifically based EU policy targets for nutrient loss and soil fertility evaluation.  相似文献   
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