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551.
552.
We developed and evaluated a methodology to prioritise pathogens for a wildlife disease surveillance strategy in New Zealand. The methodology, termed 'rapid risk analysis' was based on the import risk analysis framework recommended by the Office Internationale des Epizooties (OIE), and involved: hazard identification, risk estimation, and ranking of 48 exotic and 34 endemic wildlife pathogens. The risk assessment was more rapid than a full quantitative assessment through the use of a semi-quantitative approach to score pathogens for probability of entry to NZ (release assessment), likelihood of spread (exposure assessment) and consequences in free-living wildlife, captive wildlife, humans, livestock and companion animals. Risk was estimated by multiplying the scores for the probability of entry to New Zealand by the likelihood of spread by the consequences for free-living wildlife, humans and livestock. The rapid risk analysis methodology produced scores that were sufficiently differentiated between pathogens to be useful for ranking them on the basis of risk. Ranking pathogens on the basis of the risk estimate for each population sector provided an opportunity to identify the priorities within each sector alone thus avoiding value-laden comparisons between sectors. Ranking pathogens across all three population sectors by summing the risk estimate for each sector provided a comparison of total risk which may be useful for resource allocation decisions at national level. Ranking pathogens within each wildlife taxonomic group using the total risk estimate was most useful for developing specific surveillance strategies for each group.  相似文献   
553.
Knowledge of mammalian diversity is still surprisingly disparate, both regionally and taxonomically. Here, we present a comprehensive assessment of the conservation status and distribution of the world's mammals. Data, compiled by 1700+ experts, cover all 5487 species, including marine mammals. Global macroecological patterns are very different for land and marine species but suggest common mechanisms driving diversity and endemism across systems. Compared with land species, threat levels are higher among marine mammals, driven by different processes (accidental mortality and pollution, rather than habitat loss), and are spatially distinct (peaking in northern oceans, rather than in Southeast Asia). Marine mammals are also disproportionately poorly known. These data are made freely available to support further scientific developments and conservation action.  相似文献   
554.
Auxin is a plant hormone that regulates many aspects of plant growth and development. We used a chemical genetics approach to identify SIR1, a regulator of many auxin-inducible genes. The sir1 mutant was resistant to sirtinol, a small molecule that activates many auxin-inducible genes and promotes auxin-related developmental phenotypes. SIR1 is predicted to encode a protein composed of a ubiquitin-activating enzyme E1-like domain and a Rhodanese-like domain homologous to that of prolyl isomerase. We suggest a molecular context for how the auxin signal is propagated to exert its biological effects.  相似文献   
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Kendall  Helen  Clark  Beth  Li  Wenjing  Jin  Shan  Jones  Glyn. D.  Chen  Jing  Taylor  James  Li  Zhenhong  Frewer  Lynn. J. 《Precision Agriculture》2022,23(1):319-351
Precision Agriculture - Precision agriculture (PA) technologies offer a potential solution to food security and environmental challenges but, will only be successful if adopted by farmers. Adoption...  相似文献   
557.
Irrigation development induces considerable environmental change, but the expectation has been in the past that the economic and social benefits would be greater than the environmental costs. However, public attitudes change over time from acceptance of development and exploitation to greater concern regarding environmental issues and sustainability. Recently, the irrigation industry has found it difficult to communicate to the wider populace the regional benefits of irrigation and the current activities and investment undertaken to address the environmental sustainability concerns. To address this, irrigation water supply businesses are investigating using a broader reporting structure that includes financial, environmental, and social and cultural elements. This triple bottom line, holistic approach should provide a more balanced view of water use with socio-economic benefits and environmental consequences demonstrated. It is anticipated that this approach embedded in the newly developed Irrigation Sustainability Assessment Framework will lead to a more transparent and informed debate on the sustainable use of resources between all parties.  相似文献   
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559.
Fisheries-Oceanography Coordinated Investigations (FOCI) is a National Oceanic and Atmospheric Administration (NOAA) research programme seeking to understand recruitment processes of commercially exploited Alaskan fishes. The FOCI is mainly comprised of scientists at the Pacific Marine Environmental Laboratory and the Alaska Fisheries Science Center who study both the biotic and abiotic environment, including processes within larval patches through integrated field, laboratory, and modelling studies. The initial focus of studies was walleye pollock ( Theragra chakogramma ) spawning in Shelikof Strait, Gulf of Alaska. The choice of this population for our research was based on development of a large fishery and the substantial variation in recruitment that was observed in the late 1970s and early 1980s. Also, the early life history of this population is quite predictable and restricted both temporally and spatially. Walleye pollock spawn consistently in a small part of Shelikof Strait in early spring from which a large patch of eggs and later larvae is produced. In most years this concentration of larvae drifts to the south-west through the strait during April and May. Large numbers of larvae are often found in eddies which frequent the area and we have observed improved feeding conditions for larvae, in as opposed to out of eddies. We have found that first-feeding larvae have higher survival rates during calm periods, rather than in storms, and that in many years recruitment is largely set by the end of the larval period, although in some years age-0 juvenile mortality is also important. FOCI now generates information that is being used for management of this resource.  相似文献   
560.
A strain of Brachionus‘Nevada’, which belongs to the Brachionus plicatilis species complex, and is commonly found in European hatcheries, was investigated in terms of its mixis potential. Two feeding regimes used for mass culturing were employed. Rotifer populations were fed on phytoplankton (Tetraselmis suecica) and either baker's yeast, Saccharomyces cerevisiae (treatments A) or Culture Selco® (treatments B). In order to promote mixis, the salinity of the culture medium was reduced from 40 to 20 g L−1. Indeed, the rotifer populations of lower salinity (A 20, B 20) showed a twofold increase in mixis rates compared with those of higher salinity (A 40, B 40). In addition, treatment A 20 showed significantly higher levels of mixis (22.59±2.07%) compared with B 20 (16.56±1.46%). The opposite trend was observed for the parthenogenetic growth rates (A 20: 0.46±0.01; B 20: 0.62±0.01). It is thus concluded that Culture Selco leads to a higher abundance of amictic ovigerous females, whereas yeast supports a higher abundance of males and mictic females carrying resting eggs. The two types of feeding regimes can be used for different purposes in a hatchery.  相似文献   
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