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排序方式: 共有554条查询结果,搜索用时 15 毫秒
551.
552.
S Dawson K Willoughby R M Gaskell G Wood W S Chalmers 《Journal of Feline Medicine and Surgery》2001,3(1):17-22
A trivalent (feline panleucopenia, feline herpesvirus, feline calicivirus), modified live, commercially available cat vaccine was used at either 6, 9 and 12 weeks of age (early schedule) or 9 and 12 weeks of age (conventional schedule), and the serological response to vaccination was assessed. The level of maternally derived antibody present at 6 weeks of age was also established. The use of early vaccination at 6 weeks of age induced an antibody response to each virus by 9 weeks of age in a significant proportion of kittens compared with unvaccinated littermates. There was no difference between the conventionally and early-vaccinated groups in terms of antibody response to any antigen by 12 and 15 weeks of age. 相似文献
553.
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
554.
Sahlu T Dawson LJ Gipson TA Hart SP Merkel RC Puchala R Wang Z Zeng S Goetsch AL 《Journal of animal science》2009,87(1):400-418
Goat research in the United States has increased but at a rate less than that in production. Research on goat meat includes nutritional quality, packaging, color, sensory characteristics, and preslaughter management. Goat skins have value for leather, but quality of goat leather has not been extensively studied. Research in the production, quality, antibiotic residues, and sensory characteristics of goat milk and its products has aided development of the US dairy goat industry. Limited progress has been made in genetic improvement of milk or meat production. There is need to explore applications of genomics and proteomics and improve consistency in texture and functionality of goat cheeses. New goat meat and milk products are needed to increase demand and meet the diverse tastes of the American public. Despite research progress in control of mohair and cashmere growth, erratic prices and sale of raw materials have contributed to further declines in US production. Innovative and cooperative ventures are needed for profit sharing up to the consumer level. Internal parasites pose the greatest challenge to goat production in humid areas largely because of anthelmintic resistance. Study of alternative controls is required, including immunity enhancement via nutrition, vaccination, pasture management such as co-grazing with cattle, and genetic resistance. Similarly, the importance of health management is increasing related in part to a lack of effective vaccines for many diseases. Nutrition research should address requirements for vitamins and minerals, efficiencies of protein utilization, adjusting energy requirements for nutritional plane, acclimatization, and grazing conditions, feed intake prediction, and management practices for rapid-growth production systems. Moreover, efficient technology transfer methods are needed to disseminate current knowledge and that gained in future research. 相似文献