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861.
Sara Heidl Isabella Ellinger Verena Niederberger Eva E. Waltl Renate Fuchs 《Protoplasma》2016,253(6):1557-1564
The airway epithelium is a central player in the defense against pathogens including efficient mucociliary clearance and secretion of immunoglobulins, mainly polymeric IgA, but also IgG. Pulmonary administration of therapeutic antibodies on one hand, and intranasal immunization on the other, are powerful tools to treat airway infections. In either case, the airway epithelium is the primary site of antibody transfer. In various epithelia, bi-polar transcytosis of IgG and IgG immune complexes is mediated by the human neonatal Fc receptor, FcRn, but FcRn expression in the nasal epithelium had not been demonstrated, so far. We prepared affinity-purified antibodies against FcRn α-chain and confirmed their specificity by Western blotting and immunofluorescence microscopy. These antibodies were used to study the localization of FcRn α-chain in fixed nasal tissue. We here demonstrate for the first time that ciliated epithelial cells, basal cells, gland cells, and endothelial cells in the underlying connective tissue express the receptor. A predominant basolateral steady state distribution of the receptor was observed in ciliated epithelial as well as in gland cells. Co-localization of FcRn α-chain with IgG or with early sorting endosomes (EEA1-positive) but not with late endosomes/lysosomes (LAMP-2-positive) in ciliated cells was observed. This is indicative for the presence of the receptor in the recycling/transcytotic pathway but not in compartments involved in lysosomal degradation supporting the role of FcRn in IgG transcytosis in the nasal epithelium. 相似文献
862.
Xiufang Liu Yunzhi Song Fangyu Xing Ning Wang Fujiang Wen Changxiang Zhu 《Protoplasma》2016,253(5):1265-1281
863.
Cytochrome P450s constitute the largest family of enzymatic proteins in plants acting on various endogenous and xenobiotic molecules. They are monooxygenases that insert one oxygen atom into inert hydrophobic molecules to make them more reactive and hydro-soluble. Besides for physiological functions, the extremely versatile cytochrome P450 biocatalysts are highly demanded in the fields of biotechnology, medicine, and phytoremediation. The nature of reactions catalyzed by P450s is irreversible, which makes these enzymes attractions in the evolution of plant metabolic pathways. P450s are prime targets in metabolic engineering approaches for improving plant defense against insects and pathogens and for production of secondary metabolites such as the anti-neoplastic drugs taxol or indole alkaloids. The emerging examples of P450 involvement in natural product synthesis in traditional medicinal plant species are becoming increasingly interesting, as they provide new alternatives to modern medicines. In view of the divergent roles of P450s, we review their classification and nomenclature, functions and evolution, role in biosynthesis of secondary metabolites, and use as tools in pharmacology. 相似文献
864.
Lipid trafficking is vital for metabolite exchange and signal communications between organelles and endomembranes. Acyl-CoA-binding proteins (ACBPs) are involved in the intracellular transport, protection, and pool formation of acyl-CoA esters, which are important intermediates and regulators in lipid metabolism and cellular signaling. In this review, we highlight recent advances in our understanding of plant ACBP families from a cellular and developmental perspective. Plant ACBPs have been extensively studied in Arabidopsis thaliana (a dicot) and to a lesser extent in Oryza sativa (a monocot). Thus far, they have been detected in the plasma membrane, vesicles, endoplasmic reticulum, Golgi apparatus, apoplast, cytosol, nuclear periphery, and peroxisomes. In combination with biochemical and molecular genetic tools, the widespread subcellular distribution of respective ACBP members has been explicitly linked to their functions in lipid metabolism during development and in response to stresses. At the cellular level, strong expression of specific ACBP homologs in specialized cells, such as embryos, stem epidermis, guard cells, male gametophytes, and phloem sap, is of relevance to their corresponding distinct roles in organ development and stress responses. Other interesting patterns in their subcellular localization and spatial expression that prompt new directions in future investigations are discussed. 相似文献
865.
Raheleh Dehgahi Latiffah Zakaria Azhar Mohamad Alireza Joniyas Sreeramanan Subramaniam 《Protoplasma》2016,253(5):1373-1383
Dendrobium sonia-28 is a popular orchid hybrid due to its flowering recurrence and dense inflorescences. Unfortunately, it is being decimated by fungal diseases, especially those caused by Fusarium proliferatum. In this study, selection of F. proliferatum-tolerant protocorm-like bodies (PLBs) was carried out by assessing the effects of differing concentrations of fusaric acid (FA). PLBs were cultured on Murashige and Skoog (MS) medium supplemented with 0.05 to 0.2 millimolar (mM) concentrations of FA. Higher concentrations of FA increased mortality of PLBs and reduced their growth. The survival rate for 0.05 mM FA was 20 % but only 1 % at the highest dose of 0.2 mM. Additionally, two different size ranges of PLBs were investigated, and growth increased more at lower FA concentrations for larger PLBs, whilst the growth rate of smaller PLBs was inhibited at an FA concentration of 0.2 mM. Histological examination using transmission electron microscopy (TEM) and scanning electron microscopy (SEM) analyses disclosed severe cell wall and organelle damage, as well as stomatal closure in PLBs treated with the high FA concentrations. Reductions in plantlet growth were much greater at the highest concentrations of FA. Some randomly amplified polymorphic DNA (RAPD) markers clearly discriminated between selected and non-selected variants of Dendrobium sonia-28, showing different banding patterns for each FA concentration and specific bands for selected and control plants. 相似文献
866.
Cayetana Martinez-Maza Sarah E. Freidline Andre Strauss Manuel Nieto-Diaz 《Evolutionary biology》2016,43(1):60-80
Adult craniofacial morphology results from complex processes that involve growth by bone modelling and interactions of skeletal components to keep a functional and structural balance. Previous analyses of growth dynamics in humans revealed critical changes during late ontogeny explaining particular morphological features in our species. Data on bone modelling patterns from other primate species could help us to determine whether postnatal changes in the growth dynamics of the craniofacial complex are human specific or are shared with other primates. However, characterizations of bone modelling patterns through ontogeny in non-human hominids are scarce and restricted to isolated data on facial and mandibular regions. In the present study, we analyse the bone modelling patterns in an ontogenetic series of Pan and Gorilla to infer the growth dynamics of their craniofacial complex during postnatal development. Our results show that both Pan troglodytes and Gorilla gorilla are characterized by species-specific bone modelling patterns indicative of a mainly forward growth direction during postnatal development. Both species show minor but consistent ontogenetic changes in the distribution of bone modelling fields in specific regions of the face and mandible, in contrast to other regions which show more constant bone modelling patterns. In addition, we carry out a preliminary integrative study merging histological and geometric morphometric data. Both approaches yield highly complementary data, each analysis providing details on specific growth dynamics unavailable to the other. Moreover, geometric morphometric data show that ontogenetic variation in the modelling pattern of the mandibular ramus may be linked to sexual dimorphism. 相似文献
867.
Pascal Mège Anders Ödeen Marc Théry Damien Picard Jean Secondi 《Evolutionary biology》2016,43(1):109-118
Ultraviolet (UV) vision exists in several animal groups. Intuitively, one would expect this trait to be favoured in species living in bright environments, where UV light is the most present. However, UV sensitivity, as deduced from sequences of UV photoreceptors and/or ocular media transmittance, is also present in nocturnal species, raising questions about the selective pressure maintaining this perceptual ability. Amphibians are among the most nocturnal vertebrates but their visual ecology remains poorly understood relative to other groups. Perhaps because many of these species breed in environments that filter out a large part of UV radiation, physiological and behavioural studies of UV sensitivity in this group are scarce. We investigated the extent of UV vision in Caudata, the order of amphibians with the most nocturnal habits. We could recover sequences of the UV sensitive SWS1 opsin in 40 out of 58 species, belonging to 6 families. In all of these species, the evidence suggests the presence of functional SWS1 opsins under purifying selection, potentially allowing UV vision. Interestingly, most species whose opsin genes failed to amplify exhibited particular ecological features that could drive the loss of UV vision. This likely wide distribution of functional UV photoreceptors in Caudata sheds a new light on the visual ecology of amphibians and questions the function of UV vision in nocturnal animal species. 相似文献
868.
Richard A. Watson Rob Mills C. L. Buckley Kostas Kouvaris Adam Jackson Simon T. Powers Chris Cox Simon Tudge Adam Davies Loizos Kounios Daniel Power 《Evolutionary biology》2016,43(4):553-581
The mechanisms of variation, selection and inheritance, on which evolution by natural selection depends, are not fixed over evolutionary time. Current evolutionary biology is increasingly focussed on understanding how the evolution of developmental organisations modifies the distribution of phenotypic variation, the evolution of ecological relationships modifies the selective environment, and the evolution of reproductive relationships modifies the heritability of the evolutionary unit. The major transitions in evolution, in particular, involve radical changes in developmental, ecological and reproductive organisations that instantiate variation, selection and inheritance at a higher level of biological organisation. However, current evolutionary theory is poorly equipped to describe how these organisations change over evolutionary time and especially how that results in adaptive complexes at successive scales of organisation (the key problem is that evolution is self-referential, i.e. the products of evolution change the parameters of the evolutionary process). Here we first reinterpret the central open questions in these domains from a perspective that emphasises the common underlying themes. We then synthesise the findings from a developing body of work that is building a new theoretical approach to these questions by converting well-understood theory and results from models of cognitive learning. Specifically, connectionist models of memory and learning demonstrate how simple incremental mechanisms, adjusting the relationships between individually-simple components, can produce organisations that exhibit complex system-level behaviours and improve the adaptive capabilities of the system. We use the term “evolutionary connectionism” to recognise that, by functionally equivalent processes, natural selection acting on the relationships within and between evolutionary entities can result in organisations that produce complex system-level behaviours in evolutionary systems and modify the adaptive capabilities of natural selection over time. We review the evidence supporting the functional equivalences between the domains of learning and of evolution, and discuss the potential for this to resolve conceptual problems in our understanding of the evolution of developmental, ecological and reproductive organisations and, in particular, the major evolutionary transitions. 相似文献
869.
Many plants have mutualistic relationships with ants, whereby plants provide food and/or nesting sites for the symbiotic ants, and in turn the ants protect the host plants by excluding herbivores. While the ants are useful as guards, they may negatively affect host reproduction by excluding pollinators. Here we studied this potential conflict in the myrmecophytic Macaranga winkleri pollinated by the thrips Dolichothrips fialae. Behavioural responses of ant guards to pollinator thrips and their chemicals, and related chemical analyses, provide evidence that thrips deter ant-guards by secreting droplets containing ant-repelling n-decanoic acid from their anuses. This is the first report of insect pollinators repelling their host’s symbiotic guard ants to perform pollination. This is a novel strategy by which a plant host avoids interference with pollination by ant-guards in an ant–plant mutualism. The acquisition of a pollination system that is resistant to ant attacks may have facilitated the evolution of myrmecophytes in the genus Macaranga. 相似文献
870.
Paul M. Severns 《Evolutionary biology》2016,43(3):336-343
Capital breeding species, those that do not acquire resources over their reproductive period, are hypothesized to have more flexible reproductive strategies than income breeding species, enabling the former to better cope with environmental changes. Yet, empirical study of this life history attribute in a changing environment is rare. Hemileuca eglanterina (Saturniidae), a strict capital breeding, day-flying moth, should employ a different reproductive strategy to exploit temporary increases in host plant nutrient quality following fire. In wetlands, where one half was burned and the other left unburned, the number of eggs/clutch was positively correlated with host plant abundance in the absence of fire, suggesting that H. eglanterina uses a resource abundance matching reproductive strategy by default. However, following fire, H. eglanterina laid greater numbers of eggs/clutch and did not adjust clutch size to host plant abundance, appearing to shift to a host plant quality based reproductive strategy. Coinciding with the fire-induced shift in reproductive strategy, host plants from burned habitat contained a greater proportion of N-containing compounds in their foliage than plants from unburned habitat, and larvae fed only leaves from the burned habitat had significantly greater survival than siblings fed unburned foliage. These results suggest the shift in reproductive strategy by H. eglanterina following fire was adaptive and that capital breeding species can cope with sudden environmental changes via alternative reproductive strategies. 相似文献