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991.
Riccio A Mangiapia G Giordano D Flagiello A Tedesco R Bruno S Vergara A Mazzarella L di Prisco G Pucci P Paduano L Verde C 《IUBMB life》2011,63(5):346-354
In vitro, and possibly in vivo, hemoglobin polymerization and red blood cell sickling appear to be widespread in codfish. In this article, we show that the hemoglobins of the two Arctic fish Lycodes reticulatus and Gadus morhua also have the tendency to polymerize, as monitored by dynamic light scattering experiments. The elucidation of the primary structure of the single hemoglobin of the zoarcid L. reticulatus shows the presence of a large number of cysteyl residues in α and β chains. Their role in eliciting the ability to produce polymers was also addressed by MALDI-TOF and TOF-TOF mass spectrometry. The G.morhua globins are also rich in Cys, but unlike in L. reticulatus, polymerization does not seem to be disulfide driven. The widespread occurrence of the polymerization phenomenon displayed by hemoglobins of Arctic fish supports the hypothesis that this feature may bea response to stressful environmental conditions. 相似文献
992.
Recent advances in computing technology have increased interest in applying data mining to ecology. Machine learning is one of the methods used in most of these data mining applications. As is well known, approximately 80% of the resources in most data mining applications are devoted to cleaning and preprocessing the data. However, there are few studies on preprocessing the ecological data used as the input in these data mining systems. In this study, we use four different feature selection methods (χ2, Information Gain, Gain Ratio, and Symmetrical Uncertainty) and evaluate their effectiveness in preprocessing the input data to be used for inducing artificial neural networks (ANNs) and decision trees (DTs). The presence/absence of fish is the data item used to illustrate our models. Feature selection is fundamental in order to increase the performances of the models obtained. Accuracy of classification improves when a small set of optimally selected features is used. DTs and ANNs are very useful tools when applied to modeling presence/absence of Alburnus alburnus alborella. ANNs generally performed better than DT models. 相似文献
993.
Cavallari N Frigato E Vallone D Fröhlich N Lopez-Olmeda JF Foà A Berti R Sánchez-Vázquez FJ Bertolucci C Foulkes NS 《PLoS biology》2011,9(9):e1001142
The circadian clock is synchronized with the day-night cycle primarily by light. Fish represent fascinating models for deciphering the light input pathway to the vertebrate clock since fish cell clocks are regulated by direct light exposure. Here we have performed a comparative, functional analysis of the circadian clock involving the zebrafish that is normally exposed to the day-night cycle and a cavefish species that has evolved in perpetual darkness. Our results reveal that the cavefish retains a food-entrainable clock that oscillates with an infradian period. Importantly, however, this clock is not regulated by light. This comparative study pinpoints the two extra-retinal photoreceptors Melanopsin (Opn4m2) and TMT-opsin as essential upstream elements of the peripheral clock light input pathway. 相似文献
994.
A Systematic Review on the Contributions of Edible Plant and Animal Biodiversity to Human Diets 总被引:1,自引:0,他引:1
The sustainable use of natural and agricultural biodiversity in the diet can be instrumental to preserve existing food biodiversity,
address malnutrition, and mitigate adverse effects of dietary changes worldwide. This systematic review of literature summarizes
the current evidence on the contribution of plant and animal biodiversity to human diets in terms of energy intake, micronutrient
intake, and dietary diversification. Peer-reviewed studies were searched in ten databases using pre-defined search terms.
Only original studies assessing food biodiversity and dietary intake were included, resulting in a total of 34 studies. 7,
14, and 17 studies reported information in relation to energy intake, micronutrient intake, and dietary diversification, respectively.
In general, locally available foods were found to be important sources of energy, micronutrients, and dietary diversification
in the diet of particularly rural and forest communities of highly biodiverse ecosystems. The current evidence shows local
food biodiversity as important contributor of nutritious diets. Findings are, however, limited to populations living in highly
biodiverse areas. Research on the contribution of biodiversity in diets of industrialized and urban settings needs more attention.
Instruments are needed that would more appropriately measure the dietary contribution of local biodiversity. 相似文献
995.
Daniela Guicking Brigitte Fiala Frank R. Blattner Ferry Slik Maryati Mohamed Kurt Weising 《Tree Genetics & Genomes》2011,7(3):573-585
Macaranga (Euphorbiaceae) has received much ecological and evolutionary research attention as a genus that includes some of the most
conspicuous pioneer trees of Southeast Asian tropical rainforests and because of its manifold associations with ants, including
about 30 species that are obligate ant-plants (myrmecophytes). We used sequence data from three chloroplast DNA loci (ccmp5,
ccmp6, atpB-rbcL) to assess phylogeographical patterns in species of Macaranga, section Pruinosae, sampled from various regions of Borneo and the Malay Peninsula. Forty-nine chloroplast DNA haplotypes (HT) were identified
among 768 specimens from five species, Macaranga gigantea (N = 329; 23 HT), Macaranga pearsonii (N = 347; 21 HT), Macaranga puberula (N = 24; 4 HT), Macaranga hosei (N = 48; 6 HT), and Macaranga pruinosa (N = 20; 5 HT). Forty-one haplotypes were species-specific, whereas eight haplotypes were shared by two, three, or four species
and occupied internal positions in a parsimony network. Population genetic parameters based on haplotype frequencies proved
to be in a similar range in the non-myrmecophytic M. gigantea and in the ant-associated M. pearsonii, which have overlapping distributions in northern and eastern Borneo. A comparison of G
ST and N
ST values revealed a strong phylogeographic structure in both species, whereas colonization pathways suggested by the network
topology were different. Both species exhibited similar levels of haplotypic diversity and moderate to high levels of population
differentiation. There were no obvious indications for an influence of the symbiotic ant partners on the population structure
of their host plants. 相似文献
996.
Jabes D 《Current opinion in microbiology》2011,14(5):564-569
There is an urgent need for new antibacterials to target emerging multidrug-resistant bacteria. The need for such agents is rising while the efforts in antibacterial research have declined dramatically in the past few decades with the result of only four compounds belonging to new chemical classes being approved for clinical use. The main reasons that led to this critical situation are shortly described. A renewed interest in the research of new effective antimicrobials is nonetheless delivering compounds deriving mainly from modification of existing drugs, yet new chemical classes are appearing. Because many of these activities have started relatively recently, we should expect a long period before new antibiotics are added to the medical armamentarium. 相似文献
997.
Tanca A Pagnozzi D Falchi G Tonelli R Rocca S Roggio T Uzzau S Addis MF 《Proteomics》2011,11(5):1005-1011
The ability to investigate the proteome of formalin-fixed, paraffin-embedded (FFPE) tissues can be considered a major recent achievement in the field of clinical proteomics. However, gel-based approaches to the investigation of FFPE tissue proteomes have lagged behind, mainly because of insufficient quality of full-length protein extracts. Here, the 2-D DIGE technology was investigated for applicability to FFPE proteins, for internal reproducibility among replicate FFPE extracts, and for comparability between FFPE and fresh-frozen tissue profiles. The 2-D DIGE patterns obtained upon labeling and electrophoresis of replicate FFPE tissue extracts were highly reproducible, with satisfactory resolution and complexity. Moreover, the implementation of DIGE enabled to highlight and characterize the consistent differences found in the FFPE profiles compared with fresh-frozen profiles, represented by an acidic shift, directly correlated to the protein pI value, and by a reduction in spot signal intensity, directly correlated to molecular weight and percentage of lysine residues. Being constantly and reproducibly present in all FFPE tissue extract replicates at similar extents, these modifications do not appear to hinder the comparative analysis of FFPE tissue extracts by 2-D DIGE, opening the way to its application for the differential proteomic investigation of archival tissue repositories. 相似文献
998.
Common reed die-back is a widely investigated phenomenon in Central Europe, not frequently recorded in S-European areas and almost unknown in the Mediterranean Basin. Symptoms of reed decline recently observed in the Italian Peninsula provided the starting point for a detailed investigation on a reed population in one of the largest freshwater ecosystems in Central Italy. The analyses were conducted over two vegetative seasons in 19 plots at seven locations. A set of 13 morphologic and phenologic reed traits were screened, monitored and statistically analysed. The data indicated the presence of the reed die-back syndrome in a wet Mediterranean ecosystem and enabled us to highlight a set of usable traits to detect the condition of decline. Among them, the stem height and diameter, the number of nodes, the relative growth rate and the lateral root diameter resulted the most significant factors highlighting the declining condition. Some environmental characteristics of the reed stands were also taken into account. The period of submersion and the presence of standing litter emerged as important features of the stands, strictly related to the degree of decline in the population. The results draw attention to the risk, in southern Europe too, of the loss of an ecosystem which plays an important role in biodiversity conservation. 相似文献
999.
1000.
Ruiz JC D'Afonseca V Silva A Ali A Pinto AC Santos AR Rocha AA Lopes DO Dorella FA Pacheco LG Costa MP Turk MZ Seyffert N Moraes PM Soares SC Almeida SS Castro TL Abreu VA Trost E Baumbach J Tauch A Schneider MP McCulloch J Cerdeira LT Ramos RT Zerlotini A Dominitini A Resende DM Coser EM Oliveira LM Pedrosa AL Vieira CU Guimarães CT Bartholomeu DC Oliveira DM Santos FR Rabelo ÉM Lobo FP Franco GR Costa AF Castro IM Dias SR Ferro JA Ortega JM Paiva LV Goulart LR Almeida JF Ferro MI Carneiro NP 《PloS one》2011,6(4):e18551