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991.
Petsko GA 《Genome biology》2007,8(2):103
The retraction of 5 protein crystal structures has held back an entire sub-field for years due to the inordinately persuasive power of the pretty pictures that structural biology produces. All too often the first report is sketchy, superficial in its analysis, and prone to error. The second report is often more thoughtful, more useful, and is essential to the scientific process of validation and self-correction. 相似文献
992.
993.
Functional constraint and small insertions and deletions in the ENCODE regions of the human genome 总被引:1,自引:0,他引:1
Background
We describe the distribution of indels in the 44 Encyclopedia of DNA Elements (ENCODE) regions (about 1% of the human genome) and evaluate the potential contributions of small insertion and deletion polymorphisms (indels) to human genetic variation. We relate indels to known genomic annotation features and measures of evolutionary constraint. 相似文献994.
Huang da W Sherman BT Tan Q Collins JR Alvord WG Roayaei J Stephens R Baseler MW Lane HC Lempicki RA 《Genome biology》2007,8(9):R183
The DAVID Gene Functional Classification Tool uses a novel agglomeration algorithm to condense a list of genes or associated biological terms into organized classes of
related genes or biology, called biological modules. This organization is accomplished by mining the complex biological co-occurrences
found in multiple sources of functional annotation. It is a powerful method to group functionally related genes and terms
into a manageable number of biological modules for efficient interpretation of gene lists in a network context. 相似文献
995.
Wray GA 《Nature reviews. Genetics》2007,8(3):206-216
For decades, evolutionary biologists have argued that changes in cis-regulatory sequences constitute an important part of the genetic basis for adaptation. Although originally based on first principles, this claim is now empirically well supported: numerous studies have identified cis-regulatory mutations with functionally significant consequences for morphology, physiology and behaviour. The focus has now shifted to considering whether cis-regulatory and coding mutations make qualitatively different contributions to phenotypic evolution. Cases in which parallel mutations have produced parallel trait modifications in particular suggest that some phenotypic changes are more likely to result from cis-regulatory mutations than from coding mutations. 相似文献
996.
James M Wells Farzad Esni Gregory P Boivin Bruce J Aronow William Stuart Chelsea Combs Angela Sklenka Steven D Leach Andrew M Lowy 《BMC developmental biology》2007,7(1):4
Background
β-catenin is an essential mediator of canonical Wnt signaling and a central component of the cadherin-catenin epithelial adhesion complex. Dysregulation of β-catenin expression has been described in pancreatic neoplasia. Newly published studies have suggested that β-catenin is critical for normal pancreatic development although these reports reached somewhat different conclusions. In addition, the molecular mechanisms by which loss of β-catenin affects pancreas development are not well understood. The goals of this study then were; 1] to further investigate the role of β-catenin in pancreatic development using a conditional knockout approach and 2] to identify possible mechanisms by which loss of β-catenin disrupts pancreatic development. A Pdx1-cre mouse line was used to delete a floxed β-catenin allele specifically in the developing pancreas, and embryonic pancreata were studied by immunohistochemistry and microarray analysis. 相似文献997.
The availability of sequenced genomes of human and many experimental animals necessitated the development of new technologies and powerful computational tools that are capable of exploiting these genomic data and ask intriguing questions about complex nature of biological processes. This gave impetus for developing whole genome approaches that can produce functional information of genes in the form of expression profiles and unscramble the relationships between variation in gene expression and the resulting physiological outcome. These profiles represent genetic fingerprints or catalogue of genes that characterize the cell or tissue being studied and provide a basis from which to begin an investigation of the underlying biology. Among the most powerful and versatile tools are high-density DNA microarrays to analyze the expression patterns of large numbers of genes across different tissues or within the same tissue under a variety of experimental conditions or even between species. The wide spread use of microarray technologies is generating large sets of data that is stimulating the development of better analytical tools so that functions can be predicted for novel genes. In this review, the authors discuss how these profiles are being used at various stages of the drug discovery process and help in the identification of new drug targets, predict the function of novel genes, and understand individual variability in response to drugs. 相似文献
998.
Kimberly M. Carlson Gregory P. Asner R. Flint Hughes Rebecca Ostertag Roberta E. Martin 《Ecosystems》2007,10(4):536-549
Mapping biological diversity is a high priority for conservation research, management and policy development, but few studies
have provided diversity data at high spatial resolution from remote sensing. We used airborne imaging spectroscopy to map
woody vascular plant species richness in lowland tropical forest ecosystems in Hawai’i. Hyperspectral signatures spanning
the 400–2,500 nm wavelength range acquired by the NASA Airborne Visible and Infrared Imaging Spectrometer (AVIRIS) were analyzed
at 17 forest sites with species richness values ranging from 1 to 17 species per 0.1–0.3 ha. Spatial variation (range) in
the shape of the AVIRIS spectra (derivative reflectance) in wavelength regions associated with upper-canopy pigments, water,
and nitrogen content were well correlated with species richness across field sites. An analysis of leaf chlorophyll, water,
and nitrogen content within and across species suggested that increasing spectral diversity was linked to increasing species
richness by way of increasing biochemical diversity. A linear regression analysis showed that species richness was predicted
by a combination of four biochemically-distinct wavelength observations centered at 530, 720, 1,201, and 1,523 nm (r
2 = 0.85, p < 0.01). This relationship was used to map species richness at approximately 0.1 ha resolution in lowland forest reserves
throughout the study region. Future remote sensing studies of biodiversity will benefit from explicitly connecting chemical
and physical properties of the organisms to remotely sensed data. 相似文献
999.
Kate Jolly Rod S Tayor Gregory YH Lip Sheila M Greenfield Michael K Davies Russell C Davis Jonathan W Mant Sally J Singh Jackie T Ingram Jane Stubley Andrew J Stevens 《BMC cardiovascular disorders》2007,7(1):1-9
Background
We aimed to assess whether we could identify a graded association between increasing number of components of the metabolic syndrome and cardiac structural and functional abnormalities independently of predicted risk of coronary heart disease by the Framingham risk score.Methods
We conducted a cross-sectional study on a random sample of the urban population of Porto aged 45 years or over. Six hundred and eighty-four participants were included. Data were collected by a structured clinical interview with a physician, ECG and a transthoracic M-mode and 2D echocardiogram. The metabolic syndrome was defined according to ATPIII-NCEP. The association between the number of features of the metabolic syndrome and the cardiac structural and functional abnormalities was assessed by 3 multivariate regression models: adjusting for age and gender, adjusting for the 10-year predicted risk of coronary heart disease by Framingham risk score and adjusting for age, gender and systolic blood pressure.Results
There was a positive association between the number of features of metabolic syndrome and parameters of cardiac structure and function, with a consistent and statistically significant trend for all cardiac variables considered when adjusting for age and gender. Parameters of left ventricular geometry patterns, left atrial diameter and diastolic dysfunction maintained this trend when taking into account the 10-year predicted risk of coronary heart disease by the Framingham score as an independent variable, while left ventricular systolic dysfunction did not. The prevalence of left ventricular diastolic dysfunction, and the mean left ventricular mass, left ventricular diameter and left atrial diameter increased significantly with the number of features of the metabolic syndrome when additionally adjusting for systolic blood pressure as a continuous variable.Conclusion
Increasing severity of metabolic syndrome was associated with increasingly compromised structure and function of the heart. This association was independent of Framingham risk score for indirect indices of diastolic dysfunction but not systolic dysfunction, and was not explained by blood pressure level. 相似文献1000.