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81.
BackgroundThere is limited evidence on the use of high-sensitivity C-reactive protein (hsCRP) as a biomarker for selecting patients for advanced cardiovascular (CV) therapies in the modern era. The prognostic value of mildly elevated hsCRP beyond troponin in a large real-world cohort of unselected patients presenting with suspected acute coronary syndrome (ACS) is unknown. We evaluated whether a mildly elevated hsCRP (up to 15 mg/L) was associated with mortality risk, beyond troponin level, in patients with suspected ACS.Methods and findingsWe conducted a retrospective cohort study based on the National Institute for Health Research Health Informatics Collaborative data of 257,948 patients with suspected ACS who had a troponin measured at 5 cardiac centres in the United Kingdom between 2010 and 2017. Patients were divided into 4 hsCRP groups (<2, 2 to 4.9, 5 to 9.9, and 10 to 15 mg/L). The main outcome measure was mortality within 3 years of index presentation. The association between hsCRP levels and all-cause mortality was assessed using multivariable Cox regression analysis adjusted for age, sex, haemoglobin, white cell count (WCC), platelet count, creatinine, and troponin.Following the exclusion criteria, there were 102,337 patients included in the analysis (hsCRP <2 mg/L (n = 38,390), 2 to 4.9 mg/L (n = 27,397), 5 to 9.9 mg/L (n = 26,957), and 10 to 15 mg/L (n = 9,593)). On multivariable Cox regression analysis, there was a positive and graded relationship between hsCRP level and mortality at baseline, which remained at 3 years (hazard ratio (HR) (95% CI) of 1.32 (1.18 to 1.48) for those with hsCRP 2.0 to 4.9 mg/L and 1.40 (1.26 to 1.57) and 2.00 (1.75 to 2.28) for those with hsCRP 5 to 9.9 mg/L and 10 to 15 mg/L, respectively. This relationship was independent of troponin in all suspected ACS patients and was further verified in those who were confirmed to have an ACS diagnosis by clinical coding. The main limitation of our study is that we did not have data on underlying cause of death; however, the exclusion of those with abnormal WCC or hsCRP levels >15 mg/L makes it unlikely that sepsis was a major contributor.ConclusionsThese multicentre, real-world data from a large cohort of patients with suspected ACS suggest that mildly elevated hsCRP (up to 15 mg/L) may be a clinically meaningful prognostic marker beyond troponin and point to its potential utility in selecting patients for novel treatments targeting inflammation.Trial registrationClinicalTrials.gov - NCT03507309

Amit Kaura and colleagues investigate whether mildly elevated high sensitivity C-reactive protein is associated with mortality risk in patients with suspected acute coronary syndromes.  相似文献   
82.
The hypothesis that play behavior is more prevalent in larger-brained animals has recently been challenged. It may be, for example, that only certain brain structures are related to play. Here, we analyze social play behavior with regards to the cerebellum: a structure strongly implicated in motor-development, and possibly also in cognitive skills. We present an evolutionary analysis of social play and the cerebellum, using a phylogenetic comparative method. Social play frequency and relative cerebellum size are positively correlated. Hence, there appears to be a link between the evolutionary elaboration of social play and the cerebellum. Kerrie Lewis recently received her Ph.D. from the University of Durham, U.K., under the supervision of Robert Barton. She is currently working in a postdoctoral position at Duke University, conducting research into primate numerical cognition. Robert Barton is a Reader in Evolutionary Anthropology at the University of Durham. His interests comprise primate behavior and brain evolution. Both authors are keen advocates for the use of the comparative method in evolutionary studies.  相似文献   
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We utilised the retrograde transport machinery of neurones to deliver naked plasmid DNA into the central nervous system. A 5.4-kb fragment of the glycine receptor (GlyR) alpha1 subunit gene was cloned and used to drive the expression of a construct encoding for the enhanced green fluorescent protein (EGFP). Injections of the plasmid DNA in the tongue of mice resulted in the expression of the marker protein in hypoglossal motor neurones, showing that the GlyRalpha1 promoter sequence is sufficient to drive expression of the transgene. In order to determine the specificity of expression of the 5.4-kb fragment of the GlyR alpha1 subunit gene promoter, we subsequently injected the plasmid DNA into the mouse central nucleus of the amygdala. This nucleus receives projections from the parabrachial nucleus, a brainstem area that has a high density of GlyRs, and from the insular cortex, a forebrain structure devoid of GlyRs. We observed EGFP-labelled neurones in the parabrachial nucleus, but not in the insular cortex, indicating that the 5.4-kb GlyR alpha1 subunit gene promoter confers specificity of expression. This approach provides a simple and rapid way to identify, in vivo, promoter elements that mediate neurone-specific gene expression.  相似文献   
84.
Disrupting reconsolidation of drug memories reduces cocaine-seeking behavior   总被引:15,自引:0,他引:15  
Lee JL  Di Ciano P  Thomas KL  Everitt BJ 《Neuron》2005,47(6):795-801
Maladaptive memories that associate environmental stimuli with the effects of drugs of abuse are known to be a major cause of relapse to, and persistence of, a drug addictive habit. However, memories may be disrupted after their acquisition and consolidation by impairing their reconsolidation. Here, we show that infusion of Zif268 antisense oligodeoxynucleotides into the basolateral amygdala, prior to the reactivation of a well-learned memory for a conditioned stimulus (CS)-cocaine association, abolishes the acquired conditioned reinforcing properties of the drug-associated stimulus and thus its impact on the learning of a new cocaine-seeking response. Furthermore, we show that reconsolidation of CS-fear memories also requires Zif268 in the amygdala. These results demonstrate that appetitive CS-drug memories undergo reconsolidation in a manner similar to aversive memories and that this amygdala-dependent reconsolidation can be disrupted to reduce the impact of drug cues on drug seeking.  相似文献   
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Background

The social amoebae (Dictyostelia) are a diverse group of Amoebozoa that achieve multicellularity by aggregation and undergo morphogenesis into fruiting bodies with terminally differentiated spores and stalk cells. There are four groups of dictyostelids, with the most derived being a group that contains the model species Dictyostelium discoideum.

Results

We have produced a draft genome sequence of another group dictyostelid, Dictyostelium purpureum, and compare it to the D. discoideum genome. The assembly (8.41 × coverage) comprises 799 scaffolds totaling 33.0 Mb, comparable to the D. discoideum genome size. Sequence comparisons suggest that these two dictyostelids shared a common ancestor approximately 400 million years ago. In spite of this divergence, most orthologs reside in small clusters of conserved synteny. Comparative analyses revealed a core set of orthologous genes that illuminate dictyostelid physiology, as well as differences in gene family content. Interesting patterns of gene conservation and divergence are also evident, suggesting function differences; some protein families, such as the histidine kinases, have undergone little functional change, whereas others, such as the polyketide synthases, have undergone extensive diversification. The abundant amino acid homopolymers encoded in both genomes are generally not found in homologous positions within proteins, so they are unlikely to derive from ancestral DNA triplet repeats. Genes involved in the social stage evolved more rapidly than others, consistent with either relaxed selection or accelerated evolution due to social conflict.

Conclusions

The findings from this new genome sequence and comparative analysis shed light on the biology and evolution of the Dictyostelia.
  相似文献   
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