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Current MS-based proteomics has facilitated the identification of large numbers of proteins from complex mixtures. The bovine plasma proteome has the potential to provide a wealth of information concerning the biological state of an animal. However, during MS-based experiments, higher abundance proteins such as albumin and immunoglobulin G (IgG) can hinder the identification of potentially important proteins that are present in much lower abundance. While a variety of readily available technologies exist for the depletion of multiple high-abundance proteins from human, mouse and rat samples, there are few available for bovine. In this study, we report the depletion of >97% of albumin and >92% of IgG from bovine plasma. 相似文献
916.
Background
Camouflage patterns that hinder detection and/or recognition by antagonists are widely studied in both human and animal contexts. Patterns of contrasting stripes that purportedly degrade an observer's ability to judge the speed and direction of moving prey ('motion dazzle') are, however, rarely investigated. This is despite motion dazzle having been fundamental to the appearance of warships in both world wars and often postulated as the selective agent leading to repeated patterns on many animals (such as zebra and many fish, snake, and invertebrate species). Such patterns often appear conspicuous, suggesting that protection while moving by motion dazzle might impair camouflage when stationary. However, the relationship between motion dazzle and camouflage is unclear because disruptive camouflage relies on high-contrast markings. In this study, we used a computer game with human subjects detecting and capturing either moving or stationary targets with different patterns, in order to provide the first empirical exploration of the interaction of these two protective coloration mechanisms.Results
Moving targets with stripes were caught significantly less often and missed more often than targets with camouflage patterns. However, when stationary, targets with camouflage markings were captured less often and caused more false detections than those with striped patterns, which were readily detected.Conclusions
Our study provides the clearest evidence to date that some patterns inhibit the capture of moving targets, but that camouflage and motion dazzle are not complementary strategies. Therefore, the specific coloration that evolves in animals will depend on how the life history and ontogeny of each species influence the trade-off between the costs and benefits of motion dazzle and camouflage. 相似文献917.
Li M Gustchina A Matúz K Tözsér J Namwong S Goldfarb NE Dunn BM Wlodawer A 《The FEBS journal》2011,278(22):4413-4424
Interactions between the protease (PR) encoded by the xenotropic murine leukemia virus-related virus and a number of potential inhibitors have been investigated by biochemical and structural techniques. It was observed that several inhibitors used clinically against HIV PR exhibit nanomolar or even subnanomolar values of K(i) , depending on the exact experimental conditions. Both TL-3, a universal inhibitor of retroviral PRs, and some inhibitors originally shown to inhibit plasmepsins were also quite potent, whereas inhibition by pepstatin A was considerably weaker. Crystal structures of the complexes of xenotropic murine leukemia virus-related virus PR with TL-3, amprenavir and pepstatin A were solved at high resolution and compared with the structures of complexes of these inhibitors with other retropepsins. Whereas TL-3 and amprenavir bound in a predictable manner, spanning the substrate-binding site of the enzyme, two molecules of pepstatin A bound simultaneously in an unprecedented manner, leaving the catalytic water molecule in place. 相似文献
918.
Corthals GL Dunn M James P Gil C Penque D Albar JP Andrén P Rabilloud T Marko-Varga G 《Journal of Proteomics》2011,75(1):18-22
The following report provides an overview of the discussions and outcome of the EuPA General Council meeting that took place in Estoril 20-21 October 2010. During the annual meeting future policy and action plans in a variety of areas are decided. Several important points were decided upon during this meeting including the expansion of the EuPA Executive Committee by introducing a new EuPA committee - EuPA Developments - that will initially spearhead activities in standardisation, imaging ms and biobanking. The EuPA General Council also invited Russia as its 17th member. More details about these and additional activities are presented in the article. 相似文献
919.
Capsule Vegetation structure and invertebrate abundance interact to influence both foraging sites and nestling provisioning rate; when invertebrate availability is low, adults may take greater risks to provide food for their young. Aims To investigate nesting and foraging ecology in a declining farmland bird whose fledging success is influenced by the availability of invertebrate prey suitable for feeding to offspring, and where perceived predation risk during foraging can be mediated by vegetation structure. Methods Provisioning rates of adult Yellowhammers feeding nestlings were measured at nests on arable farmland. Foraging sites were compared with control sites of both the same and different microhabitats; provisioning rate was related to habitat features of foraging‐sites. Results Foraging sites had low vegetation density, probably enhancing detection of predators, or high invertebrate abundance at high vegetation density. Parental provisioning rate decreased with increasing vegetation cover at foraging sites with high invertebrate abundance; conversely, where invertebrate abundance was low, provisioning rate increased with increasing vegetation cover. Conclusions Vegetation structure at foraging sites suggests that a trade‐off between predator detection and prey availability influences foraging site selection in Yellowhammers. Associations between parental provisioning rate and vegetation variables suggest that where invertebrate abundance is high birds increase time spent scanning for predators at higher vegetation densities; however, when prey are scarce, adults may take more risks to provide food for their young. 相似文献
920.
The diet of the New Zealand orange perch, Lepidoperca aurantia, was determined from examination of stomach contents of 248 specimens, primarily adults, sampled by bottom trawl on Chatham Rise, east of South Island, New Zealand, over three years. The diet was dominated by euphausiids (87% of total prey weight), with the remainder comprising mostly hyperiid amphipods (4%) and semi-pelagic teleost fish (7%). Orange perch are selective feeders specialising on small semi-pelagic crustaceans. They have an estimated trophic level of 3.4, classifying them as low-level carnivores. A multivariate analysis examined the influence on diet of a set of biological and environmental predictors; year and time of day were found to be the most influential variables, explaining 24% of the deviance in diet. 相似文献