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1.
Antoni Sicras-Mainar Javier Rejas Ruth Navarro Milagrosa Blanca Ángela Morcillo Raquel Larios Soledad Velasco Carme Villarroya 《Arthritis research & therapy》2009,11(2):R54-14
Introduction
The objective of this study was to analyze health care and non-health care resource utilization under routine medical practice in a primary care setting claims database and to estimate the incremental average cost per patient per year of fibromyalgia syndrome (FMS) compared with a reference population. 相似文献2.
Function of Cancer Associated Genes Revealed by Modern Univariate and Multivariate Association Tests
Malka Gorfine Boaz Goldstein Alla Fishman Ruth Heller Yair Heller Ayelet T. Lamm 《PloS one》2015,10(5)
Copy number variation (CNV) plays a role in pathogenesis of many human diseases, especially cancer. Several whole genome CNV association studies have been performed for the purpose of identifying cancer associated CNVs. Here we undertook a novel approach to whole genome CNV analysis, with the goal being identification of associations between CNV of different genes (CNV-CNV) across 60 human cancer cell lines. We hypothesize that these associations point to the roles of the associated genes in cancer, and can be indicators of their position in gene networks of cancer-driving processes. Recent studies show that gene associations are often non-linear and non-monotone. In order to obtain a more complete picture of all CNV associations, we performed omnibus univariate analysis by utilizing dCov, MIC, and HHG association tests, which are capable of detecting any type of association, including non-monotone relationships. For comparison we used Spearman and Pearson association tests, which detect only linear or monotone relationships. Application of dCov, MIC and HHG tests resulted in identification of twice as many associations compared to those found by Spearman and Pearson alone. Interestingly, most of the new associations were detected by the HHG test. Next, we utilized dCov''s and HHG''s ability to perform multivariate analysis. We tested for association between genes of unknown function and known cancer-related pathways. Our results indicate that multivariate analysis is much more effective than univariate analysis for the purpose of ascribing biological roles to genes of unknown function. We conclude that a combination of multivariate and univariate omnibus association tests can reveal significant information about gene networks of disease-driving processes. These methods can be applied to any large gene or pathway dataset, allowing more comprehensive analysis of biological processes. 相似文献
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Sheryl Coombs Ruth A. Conley 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1997,180(4):401-415
Extracellular, single unit recording techniques were used to measure the responses of posterior lateral line nerve fibers
to a 50-Hz dipole source that slowly changed its location along the length of the fish. The flow-field equations for a dipole
source were used to model the pressure gradient pattern and thus, the expected excitation pattern along a linear array of
lateral line receptor organs for different source locations. Finally, excitation patterns were similarly modeled along the
left and right side of the fish's head for actual steps taken by sculpin in approach pathways to the 50-Hz dipole source.
Spatial histograms of posterior lateral line nerve fiber responses to different locations of the dipole source could be predicted
from pressure gradient patterns modeled from the flow-field equations, confirming that the modeling approach applied to behavioral
results was a good predictor of excitation patterns likely to be encoded by the lateral line periphery. An examination of
how modeled excitation patterns changed from one position to the next in typical approach pathways and how patterns differed
between positions from which successful and unsuccessful strikes were launched suggests that approach and strike strategies
can indeed be explained by the information available in excitation patterns. In particular, changes in the spatial distribution
of pressure gradient directions (polarities), available only when the source is lateral (as opposed to directly in front of
the fish), appear to enhance the ability of sculpin to determine source distance. Without such information, misses are more
likely to occur and successful strikes are more likely to be launched from short distances only.
Accepted: 23 October 1996 相似文献
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Harriet M. Jackson Kristen D. Onos Keating W. Pepper Leah C. Graham Ellen C. Akeson Candice Byers Laura G. Reinholdt Wayne N. Frankel Gareth R. Howell 《PloS one》2015,10(5)
Alzheimer’s disease (AD) is a leading cause of dementia in the elderly and is characterized by amyloid plaques, neurofibrillary tangles (NFTs) and neuronal dysfunction. Early onset AD (EOAD) is commonly caused by mutations in amyloid precursor protein (APP) or genes involved in the processing of APP including the presenilins (e.g. PSEN1 or PSEN2). In general, mouse models relevant to EOAD recapitulate amyloidosis, show only limited amounts of NFTs and neuronal cell dysfunction and low but significant levels of seizure susceptibility. To investigate the effect of genetic background on these phenotypes, we generated APPswe and PSEN1de9 transgenic mice on the seizure prone inbred strain background, DBA/2J. Previous studies show that the DBA/2J genetic background modifies plaque deposition in the presence of mutant APP but the impact of PSEN1de9 has not been tested. Our study shows that DBA/2J.APPswePSEN1de9 mice are significantly more prone to premature lethality, likely to due to lethal seizures, compared to B6.APPswePSEN1de9 mice—70% of DBA/2J.APPswePSEN1de9 mice die between 2-3 months of age. Of the DBA/2J.APPswePSEN1de9 mice that survived to 6 months of age, plaque deposition was greatly reduced compared to age-matched B6.APPswePSEN1de9 mice. The reduction in plaque deposition appears to be independent of microglia numbers, reactive astrocytosis and complement C5 activity. 相似文献
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