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961.
The historically southeastern mosquito species Culex erraticus has over the last 30 years undergone a marked expansion north. We evaluated this species’ potential to participate in local disease cycles in the northeastern USA by identifying the vertebrate sources of blood in Cx. erraticus specimens from New Jersey. We found that the majority of bloodmeals (92.6%) were derived from birds, followed by 6.8% from mammals (of which half were human), and a single amphibian bloodmeal from a spring peeper (0.56%). Medium- and large-sized water birds from the order Pelecaniformes made up 60.4% of the bird species and 55.9% of all identified hosts. This group of birds is known enzootic hosts of arboviruses such as eastern equine encephalitis virus, for which Cx. erraticus is a competent vector. Additionally, we screened blooded mosquitoes for avian malaria parasites and identified three different lineages of Plasmodium, including what may represent a new Plasmodium species (likely a wetland bird specialist) in bloodmeals from Green Herons, a Great Egret, and a Double-Crested Cormorant. Our results support the utility of mosquito bloodmeals as sources of information about circulating wildlife pathogens and reveal the potential of range-expanding species to intensify local zoonoses and bridge enzootic pathogens to humans.  相似文献   
962.
Climate change is predicted to result in increased occurrence and intensity of drought in many regions worldwide. By increasing plant physiological stress, drought is likely to affect the floral resources (flowers, nectar and pollen) that are available to pollinators. However, little is known about impacts of drought at the community level, nor whether plant community functional composition influences these impacts. To address these knowledge gaps, we investigated the impacts of drought on floral resources in calcareous grassland. Drought was simulated using rain shelters and the impacts were explored at multiple scales and on four different experimental plant communities varying in functional trait composition. First, we investigated the effects of drought on nectar production of three common wildflower species (Lathyrus pratensis, Onobrychis viciifolia and Prunella vulgaris). In the drought treatment, L. pratensis and P. vulgaris had a lower proportion of flowers containing nectar and O. viciifolia had fewer flowers per raceme. Second, we measured the effects of drought on the diversity and abundance of floral resources across plant communities. Drought reduced the abundance of floral units for all plant communities, irrespective of functional composition, and reduced floral species richness for two of the communities. Functional diversity did not confer greater resistance to drought in terms of maintaining floral resources, probably because the effects of drought were ubiquitous across component plant communities. The findings indicate that drought has a substantial impact on the availability of floral resources in calcareous grassland, which will have consequences for pollinator behaviour and populations.  相似文献   
963.
Household air pollution (HAP) is a leading cause of morbidity and mortality worldwide. To limit HAP exposure and environmental degradation from biomass fuel use, the Government of Ghana promotes liquefied petroleum gas (LPG) use in rural Ghana via the Rural LPG program (RLP). We assessed the experiences of the RLP in 2015, 2 years after its launch. A mixed methods approach was used involving Focus Group Discussions (19) and in-depth interviews (25). In addition, a survey questionnaire was administered to elicit socio-demographic characteristics, household cooking practices and stove use patterns of 200 randomly selected respondents. At about 9 months after LPG acquisition,?<?5% of LPG beneficiaries used their stoves. Some of the reasons ascribed to the low usage of the LPG cookstoves were financial constraints, distance to LPG filling point and fear of burns. Community members appreciate the convenience of using LPG. Our results underscore a need for innovative funding mechanisms contextualized within an overall economic empowerment of rural folks to encourage sustained LPG use. It emphasizes the need for innovative accessibility interventions. This could include establishing new LPG filling stations in RLP beneficiary districts to overcome the barriers to sustained LPG use.  相似文献   
964.
965.
966.
There is growing interest in evaluating the impact that management intensity of agroecosystems has on animal communities and their ecological functions. Dung beetles are a highly used focal taxon for assessing the effects of anthropogenic disturbances and management practices on biodiversity. In the Lacandona rainforest region in southern Mexico, we quantified several metrics of the dung beetle community (number of species, number of individuals, total biomass, mean beetle size) and four of their ecological functions (dung removal, soil excavation, seed dispersal, seed exhumation) in conserved rainforest and three agroforestry systems with different management intensities: rustic cocoa, polyculture cocoa, and rubber monoculture. We also assessed the correlation between dung removal and the other functions, as well as the relationships between functions and community metrics. Land-use type affected the dung beetle communities as well as their functions, with negative effects on response variables in the most intensely managed agroecosystems (polyculture cocoa and rubber). Rustic cocoa had values similar to those of the conserved forest for all functions and community metrics, except the mean number of species per trap. Dung removal was correlated with the other ecological functions. The mean number of species per trap was significantly associated with all four functions. In our study region rustic cocoa plantations favor the maintenance of a high proportion of dung beetle species and maintain their ecological functions. Our findings corroborate that agroecosystems with less intense management may contribute to buffering the effects of landscape homogenization caused by more intensely managed agroecosystems, such as rubber plantations.  相似文献   
967.
Germinal center kinase-like kinase (GLK, also known as MAP4K3) has been hypothesized to have an effect on key cellular activities, including inflammatory responses. GLK is required for activation of protein kinase C-θ (PKCθ) in T cells. Controlling the activity of T helper cell responses could be valuable for the treatment of autoimmune diseases. This approach circumvents previous unsuccessful approaches to target PKCθ directly. The use of structure based drug design, aided by the first crystal structure of GLK, led to the discovery of several inhibitors that demonstrate potent inhibition of GLK biochemically and in relevant cell lines.  相似文献   
968.
Primate seed dispersal plays crucial roles in many ecological processes at various levels of biological organization: from plant population genetics and demography to community assembly and ecosystem function. Although research on primate seed dispersal has advanced significantly in the last 20–30 years, many aspects are still poorly understood. Here, we discuss some new challenges that we need to address, as well as some old ones that still need our attention, highlighting examples from the Neotropics. Despite new analytical tools from network theory, research on primate seed dispersal rarely takes a community-wide approach, thus limiting our understanding of its evolutionary, ecological, and conservation implications. Of particular relevance for conservation are changes caused by landscape-scale processes (e.g., forest loss and fragmentation), but these effects need to be assessed using a landscape approach, which is currently absent in primate seed dispersal research. Agroecosystems can play a key role in maintaining primate seed dispersal in anthropogenic landscapes, but this topic remains poorly studied. Primate seed dispersal research will need to play a role in refaunation projects aimed at restoring plant–animal interactions. Old challenges that we still need to address include the long-term effects of primate declines on plant populations and communities, and the role of primate seed dispersal in the regeneration of degraded habitats. If we take advantage of all tools provided by modern science, from powerful methods of data analyses to molecular techniques, and combine them with strong multidisciplinary collaborations, the future of primate seed dispersal research will indeed be exciting.  相似文献   
969.
970.
Integrating classical biological control with other management techniques such as herbicide, fire, mechanical control, grazing, or plant competition, can be the most effective way to manage invasive weeds in natural areas and rangelands. Biological control agents can be protected from potential negative impacts of these weed control methods through untreated refugia or by applying the treatment at a time when the agent is not vulnerable. A literature review of experiments that integrated biological control with other management strategies from 1987 to 2017 yielded 39 terrestrial and 16 aquatic studies. The tactics most frequently integrated with biological control were herbicide applications and plant competition. Despite numerous examples of successful programs and calls for more widespread integration of biological control with other weed management strategies, there was no increase in the number of studies reported annually over time. Additional studies investigating the ecological and economic benefits of integrated weed management are needed.  相似文献   
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