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281.
The role of deadwood on biodiversity conservation of forest ecosystems is widely recognised. Interest on deadwood has increased in the last years, and forest management policy regards deadwood as indicator of sustainable forest management.  相似文献   
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The purpose of this study was to characterize the fecal microbiota of horses with acute and chronic diarrhea before and after fecal microbiota transplantation (FMT). Six client-owned horses with acute and chronic diarrhea received FMT from 2 healthy donor horses. Microbiota analysis using next-generation sequencing was performed on fecal samples collected before and 2 and 7 d after FMT. Signs of diarrhea improved in 4 horses, whereas the remaining 2 horses did not survive. There was a significant difference in the number of bacterial species between donors and recipients (P < 0.05). The Order Lactobacillales and the genera Lactobacillus, Intestinimonas, and Streptococcus were increased in the microbiota of diarrheic horses, and Saccharofermentans genus increased in healthy donors. The results suggest that FMT from the healthy donors was not effective over a 7-day period as it did not change the fecal microbiota of the diarrheic horses. Further research to improve the efficacy of FMT in horses is needed.  相似文献   
283.
The study of the secondary metabolites contained in the organic extract of Caribbean sponge Smenospongia aurea led to the isolation of smenothiazole A (3) and B (4), hybrid peptide/polyketide compounds. Assays performed using four solid tumor cell lines showed that smenothiazoles exert a potent cytotoxic activity at nanomolar levels, with selectivity over ovarian cancer cells and a pro-apoptotic mechanism.  相似文献   
284.
Most research on the P450 (CYP) system in teleosts has been done on environmental factors that influence their induction. Less is known about CYP metabolism of aquaculture antibiotics. This article outlines the impact of aquaculture antimicrobials on the piscine CYP system, with particular regard to interactions with tetracyclines, fluoroquinolones, sulphonamides, berberine and chloramphenicol, as paradigms for current, potential and discontinued piscine antimicrobial drugs. It gives an overview of literature reports and advances in the field of biological significance of the CYP in fish. Emphasis has been placed on highlighting the most significant isoforms for biotransformation of drugs, and their drug response mechanisms. The challenge is to elucidate the differences in responses of CYP enzymes in different species to antimicrobial treatment as they may have relevance for the use of antimicrobials in aquaculture, especially as drug interactions with the fish CYP may alter their distribution, metabolism and elimination. They can impact the metabolism of other drugs metabolized by the same system with an effect on the physiology of fish administered these antimicrobials. Also, they can affect the persistence of residues and the length of the withdrawal period. For food animals such as farmed fish, this knowledge is a fundamental biomedical goal.  相似文献   
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There is increased recognition of a common suite of global challenges that hamper food system sustainability at the community scale. Food price volatility, shortages of basic commodities, increased global rates of obesity and non-communicable food-related diseases, and land grabbing are among the impediments to socially just, economically robust, ecologically regenerative and politically inclusive food systems. While international political initiatives taken in response to these challenges (e.g. Via Campesina) and the groundswell of local alternatives emerging in response to challenges are well documented, more attention is needed to the analysis of similarities between community approaches to global pressures. While we are not suggesting the application of a template set of good practices, the research reported in this paper point to the benefits of both sharing good practices and enabling communities to adopt good practices that are suited to their place-based capacities. The work also suggests that sharing community-derived good practices can support and reinforce global networks of sustainable community food systems, foster knowledge co-creation and ultimately cement collective action to global pressures. In turn these networks could enhance the sustainability and resilience of community food systems and facilitate wide scale food system transformation.  相似文献   
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  • ? The alluvial forests of the Ticino valley have been greatly reduced in size and are now represented by only a small number of fragmented remnants. To study the natural development of the black locust, an invasive species, on relatively undisturbed lowland forests, two permanent plots were established in 2005 in the “Siro Negri” Forest Reserve.
  • ? The black locust became established almost exclusively between 1940 and 1960. The observed dynamic of the black locust in the Reserve was very similar to what has been observed in its native North American range: following the initial colonization, the black locust firmly established itself in the dominant and intermediate layers but did not regenerate. In addition to the absence of a significant younger population, the decline of the black locust is evident in an elevated mortality rate and higher proportion of black locust biomass in the total coarse woody debris (CWD)
  • ? Our results support the hypothesis that the best strategy to control the spread of black locust is to avoid disturbances that favour black locust colonization, and to wait for natural suppression of the species by other trees. Due to the lack of past reference conditions and the future uncertainties, ongoing monitoring will be needed to fully understand the dynamics of forest ecosystem change in the Reserve.
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    290.
    The objective of this work was to test and compare different techniques used in tests for compatibility between the entomopathogenic fungus Beauveria bassiana (Balsamo) Vuill and phytosanitary products, in order to develop a protocol for in vitro tests. Four modes of contact were studied between B bassiana (CG432) and the fungicides iprodione (Rovral) 500 g litre(-1) SC) and azoxystrobin (Amistar) 500 g kg(-1) WG), and the insecticide endosulfan (Thiodan) 350 g litre(-1) EC), at three rates. The techniques consisted in incorporating the products into the culture medium (IM), combining the conidia into the products mix (MP) and spraying the products before (SB) and after (SA) inoculation of the fungus on Petri dishes. The fungitoxic effect of the products was studied on the basis of parameters such as germination, colony-forming units (CFUs), vegetative growth and sporulation. The effect of azoxystrobin on conidial germination was significantly higher in the IM technique than in the other techniques. With regard to CFUs, the IM and SB techniques showed the greatest differences relative to the control. Vegetative growth and sporulation were more affected when azoxystrobin was sprayed before the fungus was applied. At the commercial rate, iprodione had a greater effect on the CFU parameter in the IM and MP techniques, and on vegetative growth in the IM technique, than the other techniques used; however, there was no significant difference occurred between the techniques at the commercial rate with respect to germination and sporulation. Endosulfan was more toxic to germination in techniques SB and SA, and to the CFUs parameter in techniques IM and MP. As to vegetative growth and sporulation, regardless of rate, a more pronounced effect was observed in IM than in the other techniques. It can be inferred that there are differences between techniques and that a standardization of the compatibility tests is necessary. Another inference is that these techniques should reflect realistic exposure of the fungus to chemical formulations under field conditions.  相似文献   
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