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991.
Lithium–sulfur batteries (LSBs) are considered promising candidates for the next‐generation energy‐storage systems due to their high theoretical capacity and prevalent abundance of sulfur. Their reversible operation, however, encounters challenges from both the anode, where dendritic and dead Li‐metal form, and the cathode, where polysulfides dissolve and become parasitic shuttles. Both issues arise from the imperfection of interphases between electrolyte and electrode. Herein, a new lithium salt based on an imide anion with fluorination and unsaturation in its structure is reported, whose interphasial chemistries resolve these issues simultaneously. Lithium 1, 1, 2, 2, 3, 3‐hexafluoropropane‐1, 3‐disulfonimide (LiHFDF) forms highly fluorinated interphases at both anode and cathode surfaces, which effectively suppress formation of Li‐dendrites and dissolution/shuttling of polysulfides, and significantly improves the electrochemical reversibility of LSBs. In a broader context, this new Li salt offers a new perspective for diversified beyond Li‐ion chemistries that rely on a Li‐metal anode and active cathode materials.  相似文献   
992.
Local adaptation of plants along environmental gradients provides strong evidence for clinal evolution mediated by natural selection. Plants have developed diverse strategies to mitigate stress, for example, drought escape is a phenological strategy to avoid drought stress, while polyploidy was proposed as a genomic adaptation to stress. Polyploidy as an adaptation to aridity (an environmental parameter integrating temperature and precipitation) was previously documented in annual Brachypodium spp. (Poaceae) in the Western Mediterranean. Here, we examined whether polyploidy or phenology are associated with aridity in annual Brachypodium spp. along the aridity gradient in the Eastern Mediterranean. Using flow cytometry, we determined ploidy levels of plants from natural populations along the Israeli gradient, spanning ∼424 km from mesic Mediterranean to extreme desert climates. In a common garden we recorded time of seedling emergence, flowering and senescence. We tested whether the proportion of allotetraploids in the populations and phenological traits were associated with aridity. Contrary to a previous study in the Western Mediterranean, we found no effect of aridity on the proportion of allotetraploids and diploids within populations. Interestingly, phenology was associated with aridity: time of emergence was later, while flowering and senescence were earlier in desert plants. Our results indicate that in the Eastern Mediterranean, adaptation of Brachypodium to aridity is mediated mainly by phenology, rather than ploidy level. Therefore, we suggest that genome duplication is not the main driver of adaptation to environmental stress; rather, phenological change as a drought escape mechanism may be the major adaptation.  相似文献   
993.
The familial placements of Cyrtandromoea Zoll. and Wightia Wall., two small and enigmatic South‐East Asian genera, have long been controversial in Lamiales. Here we adopt a two‐step approach to resolve their phylogenetic relationships. We initially reconstructed a large‐scale phylogeny of Lamiales using six chloroplast markers (atpB, matK, ndhF, psbBTNH, rbcL, and rps4). The results showed that both Cyrtandromoea and Wightia emerged in the LMPO clade, including Lamiaceae, Mazaceae, Phrymaceae, Paulowniaceae, and Orobanchaceae. Based on the second set of six chloroplast markers (atpB, matK, ndhF, rbcL, rps16, and trnL‐F) and two nuclear ribosomal regions (external transcribed spacer and internal transcribed spacer) for the analyses focusing on the LMPO clade, our results revealed that Cyrtandromoea was consistently nested within Phrymaceae, whereas Wightia was supported as sister to Phrymaceae by the chloroplast DNA dataset or sister to Paulowniaceae by the nuclear ribosomal DNA dataset. Morphological and anatomical evidence fully supports the inclusion of Cyrtandromoea in Phrymaceae, and an updated tribal classification is done for Phrymaceae with five tribes, that is, Cyrtandromoeeae Bo Li, Bing Liu, Su Liu & Y. H. Tan, trib. nov., Diplaceae Bo Li, Bing Liu, Su Liu & Y. H. Tan, trib. nov., Leucocarpeae, Mimuleae, and Phrymeae. The conflicting phylogenetic position of Wightia indicated by different genome markers results in difficulty placing the genus in either Phrymaceae or Paulowniaceae. Considering the distinct morphological differences between Wightia and other families in the LMPO clade, we here propose a new family, Wightiaceae Bo Li, Bing Liu, Su Liu & Y. H. Tan, fam. nov., to accommodate it, which is the 26th family recognized in Lamiales.  相似文献   
994.
Taxonomy is a traditional subject, but it still receives attention and has become a topic of much discussion in recent years. Many of these discussions have raised concerns about the future of taxonomy, especially with regard to the workforce responsible for the discovery of new species in the context of declining biodiversity. Previous discussions were based on the taxonomic data of plants and animals, but the status of fungal taxonomy has not been mentioned. Fungi have one of the highest levels of biodiversity among all living organisms, second only to insects. The discussion of the future of taxonomy without the inclusion of fungal data is incomplete. Here, we present the results of analyses based on all new fungal taxa published since 1753. Fungal taxonomy is an ever‐growing area of study with increasing numbers of new taxa being described and growing numbers of fungal taxonomists. Compared with plants and most animal groups, there has been a much sharper increase in the rate at which new fungal taxa are being described. Furthermore, the number of taxonomists studying fungi has increased at a faster speed than those studying plants or animals. This indicates that fungal taxonomy is a prosperous subject and a dynamic area for scientific studies, and that it deserves much more attention and support. The study of fungal taxonomy will deepen our understanding of the biodiversity of our planet.  相似文献   
995.
Fumana is a diverse genus of the Cistaceae family, consisting of 21 currently accepted species. In this study, nuclear (ITS) and plastid (matK, trnT‐L) molecular markers were used to reconstruct the phylogeny and to estimate divergence times, including 19 species of Fumana. Phylogenetic analyses (Bayesian Inference, Maximum Parsimony and Maximum Likelihood) confirmed the monophyly of Fumana and did not support the infrageneric divisions previously established. The results support four main clades that group species that differ in vegetative and reproductive characters. Given the impossibility to define morphological characters common to all species within the clades, our proposal is to reject infrageneric divisions. Molecular dating and ancestral area analyses provide evidence for a Miocene diversification of the genus in the north‐western Mediterranean. Ancestral state reconstructions revealed ancestral character states for some traits related to xeric and arid habitats, suggesting a preadaptation to the Mediterranean climate.  相似文献   
996.
To detect the genomic constitutions and investigate the evolutionary relationships between Campeiostachys Drobov and Elymus L. species, we have cloned and analyzed 271 5S nuclear ribosomal DNA sequences from 27 accessions of these species, mostly of Chinese origin. We identified Long H1, Short S1, and Long Y1 unit classes in nine Campeiostachys or Elymus species. The identification of the three orthologous unit classes was confirmed by the neighbor‐joining tree of each unit class from PAUP and the phylogeny tree of three unit classes from MrBayes. The results suggested that these Elymus species comprise StYH haplomes and should be included in Campeiostachys. The phylogeny tree showed a clear separation between the S1 unit class and Y1 unit class. However, Y1 unit class sequences formed a sister clade to the S1 unit class, implying that although the St and Y haplomes might have some affinity, they are distinct from one another. The phylogeny tree also indicated that the five species in sect. Turczaninovia (C. dahurica var. cylindrica, C. dahurica var. dahurica, C. dahurica var. tangutorum, E. purpuraristatus, and E. dahuricus Turcz. ex Griseb. var. violeus C. P. Wang & H. L. Yang) might share a more recent common ancestor, whereas the four species in sect. Elymus (C. nutans, E. breviaristatus (Keng) Keng ex Keng f., E. sinosubmuticus (Keng) Keng f., and E. atratus (Nevski) Hand.‐Mazz.) share a close relationship. By identifying only one type of unit class for each haplome, we propose that the 5S nuclear ribosomal DNA sequences of species within Campeiostachys might have undergone haplome‐specific concerted evolution.  相似文献   
997.
Climate change poses critical challenges for population persistence in natural communities, for agriculture and environmental sustainability, and for food security. In this review, we discuss recent progress in climatic adaptation in plants. We evaluate whether climate change exerts novel selection and disrupts local adaptation, whether gene flow can facilitate adaptive responses to climate change, and whether adaptive phenotypic plasticity could sustain populations in the short term. Furthermore, we discuss how climate change influences species interactions. Through a more in‐depth understanding of these eco‐evolutionary dynamics, we will increase our capacity to predict the adaptive potential of plants under climate change. In addition, we review studies that dissect the genetic basis of plant adaptation to climate change. Finally, we highlight key research gaps, ranging from validating gene function to elucidating molecular mechanisms, expanding research systems from model species to other natural species, testing the fitness consequences of alleles in natural environments, and designing multifactorial studies that more closely reflect the complex and interactive effects of multiple climate change factors. By leveraging interdisciplinary tools (e.g., cutting‐edge omics toolkits, novel ecological strategies, newly developed genome editing technology), researchers can more accurately predict the probability that species can persist through this rapid and intense period of environmental change, as well as cultivate crops to withstand climate change, and conserve biodiversity in natural systems.  相似文献   
998.
Species concept and delimitation are fundamental to taxonomic and evolutionary studies. Both inadequate informative sites in the molecular data and limited taxon sampling have often led to poor phylogenetic resolution and incorrect species delineation. Recently, the whole chloroplast genome sequences from extensive herbarium specimen samples have been shown to be effective to amend the problem. Stachyuraceae are a small family consisting of only one genus Stachyurus of six to 16 species. However, species delimitation in Stachyurus has been highly controversial because of few and generally unstable morphological characters used for classification. In this study, we sampled 69 individuals of seven species (each with at least three individuals) covering the entire taxonomic diversity, geographic range, and morphological variation of Stachyurus from herbarium specimens for genome‐wide plastid gene sequencing to address species delineation in the genus. We obtained high‐quality DNAs from specimens using a recently developed DNA reconstruction technique. We first assembled four whole chloroplast genome sequences. Based on the chloroplast genome and one nuclear ribosomal DNA sequence of Stachyurus, we designed primers for multiplex polymerase chain reaction and high throughput sequencing of 44 plastid loci for species of Stachyurus. Data of these chloroplast DNA and nuclear ribosomal DNA internal transcribed spacer sequences were used for phylogenetic analyses. The phylogenetic results showed that the Japanese species Stachyurus praecox Siebold & Zucc. was sister to the rest in mainland China, which indicated a typical Sino‐Japanese distribution pattern. Based on diagnostic morphological characters, distinct distributional range, and monophyly of each clade, we redefined seven species for Stachyurus following an integrative species concept, and revised the taxonomy of the family based on previous reports and specimens, in particular the type specimens. Furthermore, our divergence time estimation results suggested that Stachyuraceae split from its sister group Crossosomataceae from the New World at ca. 54.29 Mya, but extant species of Stachyuraceae started their diversification only recently at ca. 6.85 Mya. Diversification time of Stachyurus in mainland China was estimated to be ca. 4.45 Mya. This research has provided an example of using the herbarium specimen‐based phylogenomic approach in resolving species boundaries in a taxonomically difficult genus.  相似文献   
999.
In China, three institutes for botanical research were established in the 1920s. They were the Department of Botany, Biological Laboratory of the Science Society of China (1922, Nanjing), the Fan Memorial Institute of Biology (1928, Beiping), and the Institute of Botany, Beiping Academy of Sciences (1929, Beiping).  相似文献   
1000.
Wasp venom is a complex mixture of biologically active components, including high molecular weight proteins, small peptides, bioactive amines, and amino acids. Peptides comprise up to 70% of dried venom. In social wasp venoms, three of the major peptide types are mastoparans, which cause mast cell degranulation, chemotactic peptides, which promote chemotaxis of polymorphonucleated leukocytes, and kinin‐related peptides, which are known to produce pain and increase vascular permeability. Among these, the bioactive tridecapeptide mastoparan is the most common and may even have antimicrobial activity. Herein we summarize the results of studies on vespid mastoparans, focusing on hornets (Vespa spp.) identified following a systematic literature search for mastoparans of hornets in the genus Vespa, the most active mastoparan research taxon. The common features of hornet mastoparans are C‐terminal amidation, amphipathic helical structure, and multiple functions such as mast cell degranulation and hemolysis, as well as membrane permeabilization. Most interestingly, all tested hornet mastoparans have strong antimicrobial activities, suggesting that they can provide useful insights into and opportunities for development of novel antibacterial peptides.  相似文献   
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