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81.
The impact on the environment of Cd, Pb and Zn emissions from the A1 motorway, one of the busiest in France, was based on a simultaneous analysis of lichens, fungi and soil.The study was conducted in 12 rest areas located along a 55 kmstretch of the motorway. Cd, Pb and Zn concentrations in the top soil horizon (0–10 cm) largely exceeded their concentrations at the control site.The Cd-, Pb- and Zn levels in fruiting bodies of fungi Armillaria mellea, Coprinus comatus, Marasmius oreades and Paxillus involutus were highly variable between sites. The contamination degree of transplanted thalliof Parmelia caperata was well correlated to the cumulated traffic on the western side. On the eastern side, heavy metals originated from the traffic but also from neighbouring sources (urbanization and agricultural practices). Although lead levels are decreasing, leaded petrol is still on offer and lead remains an indicator of vehicle pollution. 相似文献
82.
Virginie Doceul Estelle Lara Corinne Sailleau Guillaume Belbis Jennifer Richardson Emmanuel Bréard Cyril Viarouge Morgane Dominguez Pascal Hendrikx Didier Calavas Alexandra Desprat Jér?me Languille Lo?c Comtet Philippe Pourquier Jean-Fran?ois Eléou?t Bernard Delmas Philippe Marianneau Damien Vitour Stéphan Zientara 《Veterinary research》2013,44(1):31
After the unexpected emergence of Bluetongue virus serotype 8 (BTV-8) in northern Europe in 2006, another arbovirus, Schmallenberg virus (SBV), emerged in Europe in 2011 causing a new economically important disease in ruminants. The virus, belonging to the Orthobunyavirus genus in the Bunyaviridae family, was first detected in Germany, in The Netherlands and in Belgium in 2011 and soon after in the United Kingdom, France, Italy, Luxembourg, Spain, Denmark and Switzerland. This review describes the current knowledge on the emergence, epidemiology, clinical signs, molecular virology and diagnosis of SBV infection. 相似文献
83.
J. Cucherousset J.-M. Paillisson A. Carpentier V. Thoby J.-P. Damien M.-C. Eybert E. Feunteun T. Robinet 《Ecology of Freshwater Fish》2007,16(4):528-538
Abstract – For decades, the European eel Anguilla anguilla (L.) population has been declining strongly despite several management attempts, so additional experiments need to be conducted on management measures. The use of freshwater protected areas has been advocated but their efficiency has never been assessed. In this study, we investigated whether the population structure and the silver eel (mature migrating stage) production differ in fished and protected areas within a marsh wetland (Brière, 7000 ha, Northwest France), using an intensive biological study (electrofishing and trapping) and a survey of the traditional fishery (licenses, questionnaires and creel surveys). First, we found that fishermen mainly targeted >320‐mm yellow eels (sedentary stage) using pots and square dipping nets and that harvest by fishermen was highly variable at different locations in the study area. Secondly, we found differences in the size‐class structures and mortality rates between protected and fished areas. Mortality rates of eels >320 mm was positively correlated with harvest by fishermen. Furthermore, the proportion of potentially migrating eels in the total population was found to be higher in the protected areas than in fished areas (6.38% vs. 1.42%, respectively). Thirdly, we found that protected areas potentially produce 8.4% of the total silver eel production whereas they only account for 2.4% of the aquatic habitat area. We estimated that a size adjustment of protected areas to 31.1% with maintaining the current fishery would produce 50% of the potential silver eel of a fully protected marsh. Protection of freshwater areas appears to be a promising management measure and a constructive consensual way to integrate the patrimonial and societal value of the traditional fishery and the international management plans for European eels. Furthermore, freshwater protective measures can be an effective local solution if they are integrated into the framework of freshwater biodiversity management and accompanied by other management measures that focus on all eel life stages. 相似文献
84.
Type C botulism in cattle being fed ensiled poultry litter 总被引:2,自引:0,他引:2
A botulinum toxin from ensiled poultry litter which caused a major outbreak of bovine botulism was characterised as type C1. The litter produced transient ataxia when fed to two experimental calves and the clinical signs were accompanied by a transient appearance of serum toxin. Type C1 toxin was demonstrated in muscle tissues which had been taken during the outbreak from an affected animal with high circulating serum toxin, and held frozen for seven months. Clostridium botulinum type C organisms were demonstrated in faeces from another affected animal and also in kidney tissue from a third animal. These observations have implications for the diagnosis and management of future outbreaks of botulism and for the potential health risk from the meat of affected animals. 相似文献
85.
Giraud E Moulin L Vallenet D Barbe V Cytryn E Avarre JC Jaubert M Simon D Cartieaux F Prin Y Bena G Hannibal L Fardoux J Kojadinovic M Vuillet L Lajus A Cruveiller S Rouy Z Mangenot S Segurens B Dossat C Franck WL Chang WS Saunders E Bruce D Richardson P Normand P Dreyfus B Pignol D Stacey G Emerich D Verméglio A Médigue C Sadowsky M 《Science (New York, N.Y.)》2007,316(5829):1307-1312
Leguminous plants (such as peas and soybeans) and rhizobial soil bacteria are symbiotic partners that communicate through molecular signaling pathways, resulting in the formation of nodules on legume roots and occasionally stems that house nitrogen-fixing bacteria. Nodule formation has been assumed to be exclusively initiated by the binding of bacterial, host-specific lipochito-oligosaccharidic Nod factors, encoded by the nodABC genes, to kinase-like receptors of the plant. Here we show by complete genome sequencing of two symbiotic, photosynthetic, Bradyrhizobium strains, BTAi1 and ORS278, that canonical nodABC genes and typical lipochito-oligosaccharidic Nod factors are not required for symbiosis in some legumes. Mutational analyses indicated that these unique rhizobia use an alternative pathway to initiate symbioses, where a purine derivative may play a key role in triggering nodule formation. 相似文献
86.
Damien J Barrett Simon J More David A Graham Joe O'Flaherty Michael L Doherty H Michael Gunn 《Irish veterinary journal》2011,64(1):12
Animal Health Ireland has produced clear guidelines for the control of Bovine Viral Diarrhoea (BVD) infection in Irish cattle herds. In the course of developing these guidelines it was clear that a framework for regional and/or national BVD control would be required to increase the uptake of BVD control at farm level and reduce the overall prevalence of the disease. This paper assessed the economic impact of BVD, epidemiological aspects of the disease to its control, models of BVD control, international experiences of BVD control programmes. The technical knowledge and test technology exists to eradicate BVD. Indeed, many countries have successfully and others are embarking on control of the disease. The identification and prompt elimination of PI cattle will form the basis of any control programme. The trade of such animals must be curtailed. Pregnant and potentially pregnant carrying PI foetuses pose a significant threat. International experience indicates systematic, well coordinated programmes have the most success, while voluntary programmes can make good initial progress but ultimately fail. The farming community must buy into any proposed programme, and without their support, failure is likely. To buy into the programme and create such a demand for BVD control, farmers must first be well informed. It is likely that stemming economic loss and improving productivity will be the primary motivator at individual farm level. 相似文献
87.
Clément Stahl Benoit Burban Jean-Yves Goret Damien Bonal 《Annals of Forest Science》2011,68(4):771-782
• Introduction
Stem CO2 efflux (E s) is a significant component of total ecosystem respiration, but there is only scant information on seasonal variations in E s in tropical rainforests and on the main factors explaining these variations. 相似文献88.
Recent studies in the field of autoimmune thyroid diseases have largely focused on the delineation of B-cell auto-epitopes recognized by the main autoantigens to improve our understanding of how these molecules are seen by the immune system. Among these autoantigens which are targeted by autoantibodies during the development of autoimmune thyroid diseases, thyroid peroxidase is a major player. Indeed, high amounts of anti-thyroid peroxidase autoantibodies are found in the sera of patients suffering from Graves' disease and Hashimoto's thyroiditis, respectively hyper and hypothyroidism. Since anti-thyroid peroxidase autoantibodies from patients'sera mainly recognize a discontinuous immunodominant region on thyroid peroxidase and due to the complexity of the three dimensional structure of human thyroid peroxidase, numerous investigations have been necessary to closely localize this immunodominant region. The aim of the present review is to summarize the current knowledge regarding the localization of the immunodominant region recognized by human thyroid peroxidase-specific autoantibodies generated during the development of autoimmune thyroid diseases. 相似文献
89.
Colin L.D. Jenkins David Lewis Rhys Bushell Damien P. Belobrajdic Anthony R. Bird 《Journal of Cereal Science》2011,53(2):188-191
It is well established that inulin-type fructans, such as oligofructose derived from chicory root, improve gastrointestinal health via fermentation and proliferation of desirable bacteria in the large bowel. However, differences in fructan structure may contribute significantly to different fermentation and subsequent metabolic effects. Here we ascertain the chain length of two novel cereal fructans (graminan) isolated from wheat stem and barley grain, and investigate their fermentation capacity in vitro, in comparison to inulin and oligofructose. Fractions, representing three predominant fructo-oligosaccharide (FOS) size ranges from each source, were fermented and short chain fatty acids (SCFA) production was measured after 24 h of batch culture. Graminan FOS when fermented produced similar levels of total SCFA as oligofructose and inulin. The fermentation of high DP FOS fractions of barley grain and wheat stem (DP 5–15) produced more propionate than oligofructose. Graminan fructans may provide a useful alternative source of oligofructose with potential additional health benefits. 相似文献
90.
Enhancing conservation of Australian freshwater ecosystems: identification of freshwater flagship fishes and relevant target audiences 下载免费PDF全文
Brendan C Ebner David L Morgan Adam Kerezsy Scott Hardie Stephen J Beatty Jamie E Seymour James A Donaldson Simon Linke Stirling Peverell David Roberts Thomas Espinoza Nadine Marshall Frederieke J Kroon Damien W Burrows Ryan R J McAllister 《Fish and Fisheries》2016,17(4):1134-1151
Flagship species, especially mammals and birds, are commonly used to increase awareness of conservation issues in marine and terrestrial ecosystems. However, flagship species oriented programs are often ad hoc with initiatives scarce in the freshwater context. Here, we aim to identify potential flagship candidates that would appeal to a broad cross section of society at a continental scale where freshwater ecosystems are under threat from human impacts. We identified 19 species from a list of 299 Australian freshwater fishes on the basis of body size, trophic guild and threatened species status assuming these characteristics of flagship species are transferable from previous work on terrestrial flagship species. We considered the potential of species to be of international appeal but focused mostly on eight relevant interest groups within Australia. This followed the rationale that public engagement with conservation issues in freshwater systems might be more effective if the link between fish species and the decisions people make were better understood, and we acknowledge the diverging interests of stakeholders. This scoping work contributes towards addressing the challenges of connecting societies to the principles of sharing water resources with ecosystems, and represents the first continental‐scale assessment of its kind. 相似文献