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101.
1. Harmonia axyridis was first recorded in Britain in 2004. Two subsequent earlier records were received from 2003. 2. The UK Ladybird Survey, a citizen science initiative involving online recording, was launched in 2005 to encourage people across Britain to track the spread of H. axyridis. Tens of thousands of people have provided records of H. axyridis and other species of ladybirds, creating an invaluable dataset for large‐scale and long‐term research. Declines in the distribution of seven (of eight assessed) native species of ladybird have been demonstrated, and correlated with the arrival of H. axyridis, using the records collated through the UK Ladybird Survey. 3. Experimental research and field surveys have also contributed to our understanding of the ecology of H. axyridis and particularly the process of invasion. Harmonia axyridis arrived in Britain through dispersal and introduction events from regions in which it was deliberately released as a biological control agent. The rapid spread of this species has been attributed to its high natural dispersal capability by means of both flight and anthropogenic transport. A number of factors have contributed to the successful establishment and indeed dominance of this polymorphic species within aphidophagous guilds, including high reproductive capacity, intra‐guild predation, eurytopic nature, high resistance to natural enemies within the invaded range, and potentially phenotypic plasticity. 4. The global invasion by H. axyridis and subsequent research on this species has contributed to the general understanding of biological invasions. 相似文献
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104.
Neo D. Martinez 《Ecology and evolution》2023,13(3)
Elucidating how an organism''s characteristics emerge from its DNA sequence has been one of the great triumphs of biology. This triumph has cumulated in sophisticated computational models that successfully predict how an organism''s detailed phenotype emerges from its specific genotype. Inspired by that effort''s vision and empowered by its methodologies, a grand challenge is described here that aims to predict the biotic characteristics of an ecosystem, its metaphenome, from nucleic acid sequences of all the species in its community, its metagenome. Meeting this challenge would integrate rapidly advancing abilities of environmental nucleic acids (eDNA and eRNA) to identify organisms, their ecological interactions, and their evolutionary relationships with advances in mechanistic models of complex ecosystems. Addressing the challenge would help integrate ecology and evolutionary biology into a more unified and successfully predictive science that can better help describe and manage ecosystems and the services they provide to humanity. 相似文献
105.
《Ecology and evolution》2022,12(3)
Urbanization is an important driver of the diversity and abundance of tree‐associated insect herbivores, but its consequences for insect herbivory are poorly understood. A likely source of variability among studies is the insufficient consideration of intra‐urban variability in forest cover. With the help of citizen scientists, we investigated the independent and interactive effects of local canopy cover and percentage of impervious surface on insect herbivory in the pedunculate oak (Quercus robur L.) throughout most of its geographic range in Europe. We found that the damage caused by chewing insect herbivores as well as the incidence of leaf‐mining and gall‐inducing herbivores consistently decreased with increasing impervious surface around focal oaks. Herbivory by chewing herbivores increased with increasing forest cover, regardless of impervious surface. In contrast, an increase in local canopy cover buffered the negative effect of impervious surface on leaf miners and strengthened its effect on gall inducers. These results show that—just like in non‐urban areas—plant–herbivore interactions in cities are structured by a complex set of interacting factors. This highlights that local habitat characteristics within cities have the potential to attenuate or modify the effect of impervious surfaces on biotic interactions. 相似文献
106.
Stefan Linquist Brent Saylor Karl Cottenie Tyler A. Elliott Stefan C. Kremer T. Ryan Gregory 《Biological reviews of the Cambridge Philosophical Society》2013,88(3):573-584
Considerable variation exists not only in the kinds of transposable elements (TEs) occurring within the genomes of different species, but also in their abundance and distribution. Noting a similarity to the assortment of organisms among ecosystems, some researchers have called for an ecological approach to the study of transposon dynamics. However, there are several ways to adopt such an approach, and it is sometimes unclear what an ecological perspective will add to the existing co‐evolutionary framework for explaining transposon‐host interactions. This review aims to clarify the conceptual foundations of transposon ecology in order to evaluate its explanatory prospects. We begin by identifying three unanswered questions regarding the abundance and distribution of TEs that potentially call for an ecological explanation. We then offer an operational distinction between evolutionary and ecological approaches to these questions. By determining the amount of variance in transposon abundance and distribution that is explained by ecological and evolutionary factors, respectively, it is possible empirically to assess the prospects for each of these explanatory frameworks. To illustrate how this methodology applies to a concrete example, we analyzed whole‐genome data for one set of distantly related mammals and another more closely related group of arthropods. Our expectation was that ecological factors are most informative for explaining differences among individual TE lineages, rather than TE families, and for explaining their distribution among closely related as opposed to distantly related host genomes. We found that, in these data sets, ecological factors do in fact explain most of the variation in TE abundance and distribution among TE lineages across less distantly related host organisms. Evolutionary factors were not significant at these levels. However, the explanatory roles of evolution and ecology become inverted at the level of TE families or among more distantly related genomes. Not only does this example demonstrate the utility of our distinction between ecological and evolutionary perspectives, it further suggests an appropriate explanatory domain for the burgeoning discipline of transposon ecology. The fact that ecological processes appear to be impacting TE lineages over relatively short time scales further raises the possibility that transposons might serve as useful model systems for testing more general hypotheses in ecology. 相似文献
107.
Andrew Moore 《BioEssays : news and reviews in molecular, cellular and developmental biology》2009,31(1):119-124
From understanding ageing to the creation of artificial membrane‐bounded ‘organisms’, systems biology and synthetic biology are seen as the latest revolutions in the life sciences. They certainly represent a major change of gear, but paradigm shifts? This is open to debate, to say the least. For scientists they open up exciting ways of studying living systems, of formulating the ‘laws of life’, and the relationship between the origin of life, evolution and artificial biological systems. However, the ethical and societal considerations are probably indistinguishable from those of human genetics and genetically modified organisms. There are some tangible developments just around the corner for society, and as ever, our ability to understand the consequences of, and manage, our own progress lags far behind our technological abilities. Furthermore our educational systems are doing a bad job of preparing the next generation of scientists and non‐scientists. 相似文献
108.
Finn?DanielsenEmail author Neil?D.?Burgess Andrew?Balmford 《Biodiversity and Conservation》2005,14(11):2507-2542
Monitoring of biodiversity and resource use by professional scientists is often costly and hard to sustain, especially in
developing countries, where financial resources are limited. Moreover, such monitoring can be logistically and technically
difficult and is often perceived to be irrelevant by resource managers and the local communities. Alternatives are emerging,
carried out at a local scale and by individuals with little formal education. The methods adopted span a spectrum, from participatory
monitoring where aims and objectives are defined by the community, to ranger-based monitoring in protected areas. What distinguishes
these approaches is that local people or local government staff are directly involved in data collection and (in most instances)
analysis. In this issue of Biodiversity and Conservation, 15 case studies examine whether these new approaches can address
the limitations of professional monitoring in developing countries. The case studies evaluate ongoing locally-based monitoring
schemes involving more than 1500 community members in 13 countries. The papers are based on a symposium held in Denmark in
April 2004 (www. monitoringmatters.org). Here, we review how the case studies shed light on the following key issues concerning
locally-based methods: cost, sustainability, their ability to detect true local or larger-scale trends, their links to management
decisions and action, and the empowerment of local constituencies. Locally-based monitoring appears to be consistently cheap
relative to the costs of management and of professional monitoring, even though the start-up costs can be high. Most local
monitoring schemes are still young and thus their chances of being sustained over the longer term are not yet certain. However,
we believe their chances of surviving are better than many professional schemes, particularly when they are institutionalised
within existing management structures, and linked to the delivery of ecosystem goods or services to local communities. When
properly designed, local schemes yield locally relevant results that can be as reliable as those derived from professional
monitoring. Many management decisions emanate from local schemes. The decisions appear to be taken promptly, in response to
immediate threats to the environment, and often lead to community-based actions to protect habitats, species or the local
flow of ecosystem benefits; however, few local schemes have so far led to actions beyond the local scale. Locally-based monitoring
schemes often reinforce existing community-based resource management systems and lead to change in the attitude of locals
towards more environmentally sustainable resource management. Locally-derived data have considerable unexplored potential
to elucidate global patterns of change in the status of populations and habitats, the services they provide, and the threats
they face, but more effort is needed to develop effective modalities for feeding locally-derived data up to national and international
levels. 相似文献
109.
First-order intrinsic autoregressions and the de Wijs process 总被引:1,自引:0,他引:1
110.
The static fluid mosaic model of biological membranes has been progressively complemented by a dynamic membrane model that includes phospholipid reordering in domains that are proposed to extend from nanometers to microns. Kinetic models for lipolytic enzymes have only been developed for homogeneous lipid phases. In this work, we develop a generalization of the well-known surface dilution kinetic theory to cases where, in a same lipid phase, both domain and nondomain phases coexist. Our model also allows understanding the changes in enzymatic activity due to a decrease of free substrate concentration when domains are induced by peptides. This lipid reordering and domain dynamics can affect the activity of lipolytic enzymes, and can provide a simple explanation for how basic peptides, with a strong direct interaction with acidic phospholipids (such as beta-amyloid peptide), may cause a complex modulation of the activities of many important enzymes in lipid signaling pathways. 相似文献