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171.
The garnet-type phase Li7La3Zr2O12 (LLZO) attracts significant attention as an oxide solid electrolyte to enable safe and robust solid-state batteries (SSBs) with potentially high energy density. However, while significant progress has been made in demonstrating compatibility with Li metal, integrating LLZO into composite cathodes remains a challenge. The current perspective focuses on the critical issues that need to be addressed to achieve the ultimate goal of an all-solid-state LLZO-based battery that delivers safety, durability, and pack-level performance characteristics that are unobtainable with state-of-the-art Li-ion batteries. This perspective complements existing reviews of solid/solid interfaces with more emphasis on understanding numerous homo- and heteroionic interfaces in a pure oxide-based SSB and the various phenomena that accompany the evolution of the chemical, electrochemical, structural, morphological, and mechanical properties of those interfaces during processing and operation. Finally, the insights gained from a comprehensive literature survey of LLZO–cathode interfaces are used to guide efforts for the development of LLZO-based SSBs.  相似文献   
172.
Antibodies to the six chicken histone H1 subtypes and the variant histone H5 have been used in immunoprecipitations of crosslinked chromatin fragments (xChIPs) to map linker histones across the β-globin locus and the widely expressed glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and carbonic anhydrase (CA) genes in three cell types: 15-day embryo chicken erythrocytes, 15-day embryo chicken brain and the early erythroid cell line HD24. In erythrocytes, where the β-adult and β-hatching genes are active, the H1.01, H1.11L and H1.11R subtypes are substantially depleted throughout the β-globin locus and the neighboring heterochromatin, in contrast to the other four subtypes, in particular the more abundant H5. Active genes therefore carry high levels of some but not all linker histone subtypes. The situation is similar in HD24 cells, except that substantial depletions are found at the promoters of the adult βA and embryonic βρ and βε genes, despite these genes not yet being active in HD24 cells. The distributions in the brain tissue are characterised by the absence of H1.02, H1.03 and H5 from the hypersensitive site HS3 and from the β-adult 3′ enhancer for the H1.11L and H1.11R subtypes. The data show that although linker histone subtypes play distinct cell-type specific roles in gene regulation, their widespread distribution indicates they are not intrinsically inhibitory to basic chromatin transactions.  相似文献   
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Preterm delivery is associated with neurodevelopmental impairment caused by environmental and genetic factors. Dysfunction of the excitatory amino acid transporter 2 (EAAT2) and the resultant impaired glutamate uptake can lead to neurological disorders. In this study, we investigated the role of single nucleotide polymorphisms (SNPs; g.-200C>A and g.-181A>C) in the EAAT2 promoter in susceptibility to brain injury and neurodisability in very preterm infants born at or before 32-week gestation. DNA isolated from newborns’ dried blood spots were used for pyrosequencing to detect both SNPs. Association between EAAT2 genotypes and cerebral palsy, cystic periventricular leukomalacia and a low developmental score was then assessed. The two SNPs were concordant in 89.4% of infants resulting in three common genotypes all carrying two C and two A alleles in different combinations. However, in 10.6% of cases, non-concordance was found, generating six additional rare genotypes. The A alleles at both loci appeared to be detrimental and consequently, the risk of developing cerebral palsy increased four- and sixfold for each additional detrimental allele at -200 and -181 bp, respectively. The two SNPs altered the regulation of the EAAT2 promoter activity and glutamate homeostasis. This study highlights the significance of glutamate in the pathogenesis of preterm brain injury and subsequent development of cerebral palsy and neurodevelopmental disabilities. Furthermore, the described EAAT2 SNPs may be an early biomarker of vulnerability to neurodisability and may aid the development of targeted treatment strategies.  相似文献   
175.
Fungi are generally easily dispersed, able to colonise a wide variety of substrata and can tolerate diverse environmental conditions. However, despite these abilities, the diversity of fungi in the Atacama Desert is practically unknown. Most of the resident fungi in desert regions are ubiquitous. Some of them, however, seem to display specific adaptations that enable them to survive under the variety of extreme conditions of these regions, such as high temperature, low availability of water, osmotic stress, desiccation, low availability of nutrients, and exposure to high levels of UV radiation. For these reasons, fungal communities living in the Atacama Desert represent an unknown part of global fungal diversity and, consequently, may be source of new species that could be potential sources for new biotechnological products. In this review, we focus on the current knowledge of the diversity, ecology, adaptive strategies, and biotechnological potential of the fungi reported in the different ecosystems of the Atacama Desert.  相似文献   
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The host‐associated microbiome is an important player in the ecology and evolution of species. Despite growing interest in the medical, veterinary, and conservation communities, there remain numerous questions about the primary factors underlying microbiota, particularly in wildlife. We bridged this knowledge gap by leveraging microbial, genetic, and observational data collected in a wild, pedigreed population of gray wolves (Canis lupus) inhabiting Yellowstone National Park. We characterized body site‐specific microbes across six haired and mucosal body sites (and two fecal samples) using 16S rRNA amplicon sequencing. At the phylum level, we found that the microbiome of gray wolves primarily consists of Actinobacteria, Bacteroidetes, Firmicutes, Fusobacteria, and Proteobacteria, consistent with previous studies within Mammalia and Canidae. At the genus level, we documented body site‐specific microbiota with functions relevant to microenvironment and local physiological processes. We additionally employed observational and RAD sequencing data to examine genetic, demographic, and environmental correlates of skin and gut microbiota. We surveyed individuals across several levels of pedigree relationships, generations, and social groups, and found that social environment (i.e., pack) and genetic relatedness were two primary factors associated with microbial community composition to differing degrees between body sites. We additionally reported body condition and coat color as secondary factors underlying gut and skin microbiomes, respectively. We concluded that gray wolf microbiota resemble similar host species, differ between body sites, and are shaped by numerous endogenous and exogenous factors. These results provide baseline information for this long‐term study population and yield important insights into the evolutionary history, ecology, and conservation of wild wolves and their associated microbes.  相似文献   
178.
The typical soil micromycetes Aspergillus niger and Cladosporium cladosporioides from the family moniliaceae were investigated with emphasis on production of ABA into the culture medium. The both fungi were cultivated in a static liquid Czapek — Dox medium and agar Czapek — Dox medium. Aspergillus niger and Cladosporium cladosporioides showed ability to produce ABA. Analytical detection of ABA from the culture medium was performed by TLC combinated with biotest and HPLC with spectroscopy.  相似文献   
179.
Hyphae of the dimorphic fungus, Candida albicans , exhibit directional tip responses when grown in contact with surfaces. On hard surfaces or in liquid media, the trajectory of hyphal growth is typically linear, with tip re-orientation events limited to encounters with topographical features (thigmotropism). In contrast, when grown on semisolid surfaces, the tips of C. albicans hyphae grow in an oscillatory manner to form regular two-dimensional sinusoidal curves and three-dimensional helices. We show that, like thigmotropism, initiation of directional tip oscillation in C. albicans hyphae is severely attenuated when Ca2+ homeostasis is perturbed. Chelation of extracellular Ca2+ or deletion of the Ca2+ transporters that modulate cytosolic [Ca2+] (Mid1, Cch1 or Pmr1) did not affect hyphal length but curve formation was severely reduced in mid1 Δ and cch1 Δ and abolished in pmr1 Δ. Sinusoidal hypha morphology was altered in the mid1 Δ, chs3 Δ and heterozygous pmr1 Δ/ PMR1 strains. Treatments that affect cell wall integrity, changes in surface mannosylation or the provision of additional carbon sources had significant but less pronounced effects on oscillatory growth. The induction of two- and three-dimensional sinusoidal growth in wild-type C. albicans hyphae is therefore the consequence of mechanisms that involve Ca2+ influx and signalling rather than gross changes in the cell wall architecture.  相似文献   
180.
The invasion of alien species into areas beyond their native ranges is having profound effects on ecosystems around the world. In particular, novel alien predators are causing rapid extinctions or declines in many native prey species, and these impacts are generally attributed to ecological naïveté or the failure to recognise a novel enemy and respond appropriately due to a lack of experience. Despite a large body of research concerning the recognition of alien predation risk by native prey, the literature lacks an extensive review of naïveté theory that specifically asks how naïveté between novel pairings of alien predators and native prey disrupts our classical understanding of predator–prey ecological theory. Here we critically review both classic and current theory relating to predator–prey interactions between both predators and prey with shared evolutionary histories, and those that are ecologically ‘mismatched’ through the outcomes of biological invasions. The review is structured around the multiple levels of naïveté framework of Banks & Dickman (2007), and concepts and examples are discussed as they relate to each stage in the process from failure to recognise a novel predator (Level 1 naïveté), through to appropriate (Level 2) and effective (Level 3) antipredator responses. We discuss the relative contributions of recognition, cue types and the implied risk of cues used by novel alien and familiar native predators, to the probability that prey will recognise a novel predator. We then cover the antipredator response types available to prey and the factors that predict whether these responses will be appropriate or effective against novel alien and familiar native predators. In general, the level of naïveté of native prey can be predicted by the degree of novelty (in terms of appearance, behaviour or habitat use) of the alien predator compared to native predators with which prey are experienced. Appearance in this sense includes cue types, spatial distribution and implied risk of cues, whilst behaviour and habitat use include hunting modes and the habitat domain of the predator. Finally, we discuss whether the antipredator response can occur without recognition per se, for example in the case of morphological defences, and then consider a potential extension of the multiple levels of naïveté framework. The review concludes with recommendations for the design and execution of naïveté experiments incorporating the key concepts and issues covered here. This review aims to critique and combine classic ideas about predator–prey interactions with current naïveté theory, to further develop the multiple levels of naïveté framework, and to suggest the most fruitful avenues for future research.  相似文献   
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