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111.
Burgess, N., de Klerk, H., Fjeldsá, J., Crowe, T. & Rahbek, R. 2000. A preliminary assessment of congruence between biodiversity patterns in Afrotropical forest birds and forest mammals. Ostrich 71 (1 & 2): 286–291. Databases compiled for forest birds and forest mammals in the Afrotropics were tested for congruence of overall patterns and hotspots of species richness and endemism. We also looked at how well a near-minimum set of priority areas for one taxon catered for the second taxon. Overall species richness and richness hotspots of forest birds were significantly correlated with those of forest mammals, as was the case for overall endemism. Endemism hotspots for forest birds and mammals were not significantly correlated. The near-minimum set for forest birds represented 136 (76.5%) forest mammal species. The near-minimum set for forest mammals represented 350 (93.62%) forest bird species. However, to represent all forest mammals three times each, 51 grids were needed in addition to the 78 chosen as a near-minimum set for forest birds, and to represent all forest birds three times each, 43 more grids were needed in addition to the 80 selected for forest mammals. There is some congruence between the patterns of richness, endemism and near-minimum sets for forest birds and mammals in the Afrotropics, but the one taxon does not provide the ideal conservation solution for the other. Further refinement of the databases used in this paper would allow for more rigorous testing of congruence between these two groups. 相似文献
112.
Jon E. Fox 《Ethnic and racial studies》2013,36(11):1871-1889
In many respects, recent East European migrants in the UK look like past migrants to the UK: they left poorer parts of the world in search of work and the better life in the UK. But in other respects, they look different: they are white. Their putative whiteness, however, has not exempted them from the effects of racism. But while there is growing evidence of how they have been targets of racism, less attention has been focused on how they are also perpetrators of racism. The purpose of this paper is to compare the ways Hungarians and Romanians wield ‘race’ to assert and defend the relatively privileged position their putative whiteness affords them in the UK's segmented labour market. I argue that these migrants mark, evaluate and rank difference in racialized ways to secure both social-psychological and material benefits. 相似文献
113.
114.
Biomineralization in heterogeneous aqueous systems results from a complex association between pre-existing surfaces, bacterial cells, extracellular biomacromolecules, and neoformed precipitates. Fourier transform infrared (FTIR) spectroscopy was used in several complementary sample introduction modes (attenuated total reflectance [ATR], diffuse reflectance [DRIFT], and transmission) to investigate the processes of cell adhesion, biofilm growth, and biological Mn-oxidation by Pseudomonas putida strain GB-1. Distinct differences in the adhesive properties of GB-1 were observed upon Mn oxidation. No adhesion to the ZnSe crystal surface was observed for planktonic GB-1 cells coated with biogenic MnO x , whereas cell adhesion was extensive and a GB-1 biofilm was readily grown on ZnSe, CdTe, and Ge crystals prior to Mn-oxidation. IR peak intensity ratios reveal changes in biomolecular (carbohydrate, phosphate, and protein) composition during biologically catalyzed Mn-oxidation. In situ monitoring via ATR-FTIR of an active GB-1 biofilm and DRIFT data revealed an increase in extracellular protein (amide I and II) during Mn(II) oxidation, whereas transmission mode measurements suggest an overall increase in carbohydrate and phosphate moieties. The FTIR spectrum of biogenic Mn oxide comprises Mn-O stretching vibrations characteristic of various known Mn oxides (e.g., “acid” birnessite, romanechite, todorokite), but it is not identical to known synthetic solids, possibly because of solid-phase incorporation of biomolecular constituents. The results suggest that, when biogenic MnO x accumulates on the surfaces of planktonic cells, adhesion of the bacteria to other negatively charged surfaces is hindered via blocking of surficial proteins. 相似文献
115.
Adam F. Odell Luke R. Odell Jon M. Askham Hiba Alogheli Sreenivasan Ponnambalam Monica Hollstein 《The Journal of biological chemistry》2013,288(23):16704-16714
Exposure to herbal remedies containing the carcinogen aristolochic acid (AA) has been widespread in some regions of the world. Rare A→T TP53 mutations were recently discovered in AA-associated urothelial cancers. The near absence of these mutations among all other sequenced human tumors suggests that they could be biologically silent. There are no cell banks with established lines derived from human tumors with which to explore the influence of the novel mutants on p53 function and cellular behavior. To investigate their impact, we generated isogenic mutant clones by integrase-mediated cassette exchange at the p53 locus of platform (null) murine embryonic fibroblasts and kidney epithelial cells. Common tumor mutants (R248W, R273C) were compared with the AA-associated mutants N131Y, R249W, and Q104L. Assays of cell proliferation, migration, growth in soft agar, apoptosis, senescence, and gene expression revealed contrasting outcomes on cellular behavior following introduction of N131Y or Q104L. The N131Y mutant demonstrated a phenotype akin to common tumor mutants, whereas Q104L clone behavior resembled that of cells with wild-type p53. Wild-type p53 responses were restored in double-mutant cells harboring N131Y and N239Y, a second-site rescue mutation, suggesting that pharmaceutical reactivation of p53 function in tumors expressing N131Y could have therapeutic benefit. N131Y is likely to contribute directly to tumor phenotype and is a promising candidate biomarker of AA exposure and disease. Rare mutations thus do not necessarily point to sites where amino acid exchanges are phenotypically neutral. Encounter with mutagenic insults targeting cryptic sites can reveal specific signature hotspots. 相似文献
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117.
Jon M. Massman Andres Gordillo Robenzon E. Lorenzana Rex Bernardo 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2013,126(1):13-22
Maize (Zea mays L.) breeders evaluate many single-cross hybrids each year in multiple environments. Our objective was to determine the usefulness of genomewide predictions, based on marker effects from maize single-cross data, for identifying the best untested single crosses and the best inbreds within a biparental cross. We considered 479 experimental maize single crosses between 59 Iowa Stiff Stalk Synthetic (BSSS) inbreds and 44 non-BSSS inbreds. The single crosses were evaluated in multilocation experiments from 2001 to 2009 and the BSSS and non-BSSS inbreds had genotypic data for 669 single nucleotide polymorphism (SNP) markers. Single-cross performance was predicted by a previous best linear unbiased prediction (BLUP) approach that utilized marker-based relatedness and information on relatives, and from genomewide marker effects calculated by ridge-regression BLUP (RR-BLUP). With BLUP, the mean prediction accuracy (r MG) of single-cross performance was 0.87 for grain yield, 0.90 for grain moisture, 0.69 for stalk lodging, and 0.84 for root lodging. The BLUP and RR-BLUP models did not lead to r MG values that differed significantly. We then used the RR-BLUP model, developed from single-cross data, to predict the performance of testcrosses within 14 biparental populations. The r MG values within each testcross population were generally low and were often negative. These results were obtained despite the above-average level of linkage disequilibrium, i.e., r 2 between adjacent markers of 0.35 in the BSSS inbreds and 0.26 in the non-BSSS inbreds. Overall, our results suggested that genomewide marker effects estimated from maize single crosses are not advantageous (compared with BLUP) for predicting single-cross performance and have erratic usefulness for predicting testcross performance within a biparental cross. 相似文献
118.
Jon P. Mitchell 《Ethnos》2013,78(1):81-101
This paper examines local people's memories of a Maltese urban community that was demolished in the 1970s. The memories create an idealised, nostalgic picture of community harmony and solidarity prior to the demolition, but also apportion blame for its subsequent destruction. The paper argues that in such situations of physical displacement and/or social dislocation, this nostalgic process serves as a strategic resource that not only produces order and identity, but also creates legitimate moral claims against the state. The paper thereby contributes to ongoing debates about the relationship between local identity and wider political and economic processes. 相似文献
119.
Susan K. Boehlein Janine R. Shaw Donald R. McCarty Seon-Kap Hwang Jon D. Stewart L. Curtis Hannah 《Archives of biochemistry and biophysics》2013
ADP-glucose pyrophosphorylase (AGPase) is highly regulated by allosteric effectors acting both positively and negatively. Enzymes from various sources differ, however, in the mechanism of allosteric regulation. Here, we determined how the effector, inorganic phosphate (Pi), functions in the presence and absence of saturating amounts of the activator, 3-phosphoglyceric acid (3-PGA). This regulation was examined in the maize endosperm enzyme, the oxidized and reduced forms of the potato tuber enzyme as well as a small subunit chimeric AGPase (MP), which contains both maize endosperm and potato tuber sequences paired with a wild-type maize large subunit. These data, combined with our previous kinetic studies of these enzymes led to a model of Pi inhibition for the various enzymes. The Pi inhibition data suggest that while the maize enzyme contains a single effector site that binds both 3-PGA and Pi, the other enzymes exhibit more complex behavior and most likely have at least two separate interacting binding sites for Pi. The possible physiological implications of the differences in Pi inhibition distinguishing the maize endosperm and potato tuber AGPases are discussed. 相似文献
120.
Diego Pavón‐Jordán Patrik Karell Kari Ahola Heikki Kolunen Hannu Pietiäinen Teuvo Karstinen Jon E. Brommer 《Ibis》2013,155(4):823-834
Understanding how survival is affected by the environment is essential to gain insight into population dynamics and the evolution of life‐history traits as well as to identify environmental selection pressures. However, we still have little understanding of the relative effect of different environmental factors and their interactions on demographic traits and population dynamics. Here we used two long‐term, individual‐based datasets on Tawny Owl Strix aluco (1981–2010) and Ural Owl S. uralensis (1986–2010) to undertake capture‐mark‐recapture analysis of annual survival of adult females in response to three biologically meaningful environmental variables and their two‐way interactions. Despite the similar ecology of these two species, their survival was associated with different and uncorrelated environmental drivers. The main correlate of Tawny Owl survival was an inverse association with snow depth (winter severity). For Ural Owl, high food (vole) abundance improved survival during years with deep snow, but was less important during years with little snow. In addition, Ural Owl survival was strongly density‐dependent, whereas Tawny Owl survival was not. Our findings advise caution in extrapolating demographic inferences from one species to another, even when they are very closely related and ecologically similar. Analyses including only one or few potential environmental drivers of a species' survival may lead to incomplete conclusions because survival may be affected by several factors and their interactions. 相似文献