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21.
We describe the clinical features of 28 patients with juvenile dermatomyositis (JDM) and 1 patient with adult-onset dermatomyositis (DM), all of whom developed lipodystrophy (LD) that could be categorized into 1 of 3 phenotypes, generalized, partial, or focal, based on the pattern of fat loss distribution. LD onset was often delayed, beginning a median of 4.6 years after diagnosis of DM. Calcinosis, muscle atrophy, joint contractures, and facial rash were DM disease features found to be associated with LD. Panniculitis was associated with focal lipoatrophy while the anti-p155 autoantibody, a newly described myositis-associated autoantibody, was more associated with generalized LD. Specific LD features such as acanthosis nigricans, hirsutism, fat redistribution, and steatosis/nonalcoholic steatohepatitis were frequent in patients with LD, in a gradient of frequency and severity among the 3 sub-phenotypes. Metabolic studies frequently revealed insulin resistance and hypertriglyceridemia in patients with generalized and partial LD. Regional fat loss from the thighs, with relative sparing of fat loss from the medial thighs, was more frequent in generalized than in partial LD and absent from DM patients without LD. Cytokine polymorphisms, the C3 nephritic factor, insulin receptor antibodies, and lamin mutations did not appear to play a pathogenic role in the development of LD in our patients. LD is an under-recognized sequela of JDM, and certain DM patients with a severe, prolonged clinical course and a high frequency of calcinosis appear to be at greater risk for the development of this complication. High-risk JDM patients should be screened for metabolic abnormalities, which are common in generalized and partial LD and result in much of the LD-associated morbidity. Further study is warranted to investigate the pathogenesis of acquired LD in patients with DM.  相似文献   
22.
Cell cycle progression is regulated by cyclins and cyclin-dependent kinases, which are formed at specific stages of the cell cycle and regulate the G1/S and G2/M phase transitions, employing a series of "checkpoints" governed by phosphorylation of their substrates. Tumor development is associated with the loss of these checkpoint controls, and this provides an approach for the development of therapeutic agents that can specifically target tumor cells. Here, we describe the synthesis and SAR of a novel group of cytotoxic molecules that selectively induce growth arrest of normal cells in the G1 phase while inducing a mitotic arrest of tumor cells resulting in selective killing of tumor cell populations with little or no effect on normal cell viability. The broad spectrum of antitumor activity in vitro and xenograft models, lack of in vivo toxicity, and drug resistance suggest potential for use of these agents in cancer therapy.  相似文献   
23.

Purpose

To evaluate a mitotic inhibitor, ON01910.Na, as a potential chemotherapeutic agent for brain tumors using a series of PK/PD studies, which led to the evaluation of its structural analog, ON013105, a prodrug of the more lipophilic product, ON013100.

Methods

Systemic PK characterization of ON01910 and ON013105 was completed in healthy mice. Using an orthotopic U87 glioma mouse model, brain and brain tumor distribution under steady-state conditions were evaluated for ON01910.Na and ON013105/ON013100; anticancer potential following a multiple-dose schedule of 250?mg/kg/day IP for 7?days was evaluated for ON01910.Na.

Results

ON01910 exhibited low brain and brain tumor distribution with quasi-steady-state brain/plasma (Cssbrain/Cssplasma) and brain tumor/plasma (Cssbrain tumor/Cssplasma) concentration ratios of 0.03?±?0.02 and 0.14?±?0.08, respectively. Significant antiangiogenic potential and antiproliferative capacity of ON01910 in the intracerebral model was absent. ON013100 showed high brain and brain tumor penetration with Cssbrain/Cssplasma and Cssbrain tumor/Cssplasma ratios of 0.92?±?0.26 and 1.35?±?0.40, respectively; its prodrug ON013105 showed negligible brain and brain tumor penetration.

Conclusions

ON013105, not ON01910.Na, was identified as a potential anticancer drug candidate for further investigation in brain tumor chemotherapy based on the properties of ON013100.  相似文献   
24.
Linkage analysis was performed on the GAW11 Problem 2 data set using stratification to explore the effects of the environmental risk factors and the differences between mild and severe phenotypes. Analysis of the four study populations stratified by the two risk factors identified regions on chromosomes 3 and 5 with significant evidence for linkage. Other loci were sought by removing families consistent with linkage to the chromosome 3 locus. Our studies identified a locus on chromosome 3 (markers 43-46) associated with the mild phenotype in the presence of risk factor 1 and with the severe phenotype independent of risk factor 1. This suggests that distinct allelic variants at the chromosome 3 locus may cause different forms of disease. The locus identified on chromosome 5 (markers 36-39) was linked to the severe phenotype, but exposure to factor 1 or 2 may have a protective effect. The regions on chromosomes 3 and 5 appeared to have independent roles in disease etiology. Evidence for two loci on chromosome 1 linked to the mild form was found. The methods successfully identified linkages and interaction consistent with the generating model.  相似文献   
25.
Knowing the answers, we used the GAW11 data set to compare the power and efficiency of discordant versus concordant affected sib pairs for qualitative traits at different levels of penetrance. Samples of 200 concordant sib pairs outperformed discordant sib pairs for low penetrance (40%) and 70% penetrance models while at 90% penetrance they performed equally well. Increasing the sample size of discordant sib pairs to twice that of concordant pairs was not enough to reach the power of concordant sib pairs at the 40% and 70% penetrance models. For low penetrance using a combination of concordant and discordant sib pairs resulted in higher power than using discordant sib pairs alone. At 90% penetrance, the power of concordant and discordant sib pairs was similar in the region close to the gene while concordant sib pairs performed better at locations further from the gene.  相似文献   
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27.
In a study of 304 pregnant women, the prevalence of HIV infection in remote rural areas of western India was 0.7% (confidence interval 0.08-2.3%). It is nearly 2(1/2) times higher than the presumed prevalence for this part of the country.  相似文献   
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Cortical grey matter volume and sensorimotor gating in schizophrenia   总被引:2,自引:0,他引:2  
Prepulse inhibition (PPI) of the startle response, a cross-species measure of sensorimotor gating, provides a valuable tool to study the known inability of a large proportion of individuals with schizophrenia to effectively screen out irrelevant sensory input. The cortico-striato-pallido-thalamic circuitry is thought to be responsible for modulation of PPI in experimental animals. The involvement of this circuitry in human PPI is supported by observations of deficient PPI in a number of neuropsychiatric disorders that are characterised by abnormalities at some level in this circuitry, and findings of recent functional neuroimaging studies in healthy participants. The current study sought to investigate the structural neural correlates of PPI in a sample of 42 stable male outpatients with schizophrenia. Participants underwent magnetic resonance imaging (MRI) at 1.5T and were assessed (off-line) on acoustic PPI using electromyographic recordings of the orbicularis oculi muscle beneath the right eye. Optimised volumetric voxel-based morphometry implemented in SPM2 was used to investigate the relationship of PPI (prepulse onset-to-pulse onset interval 120msec) to regional grey matter (GM) volumes. Significant positive correlations were obtained between PPI and GM volume in the dorsolateral prefrontal, middle frontal and the orbital/medial prefrontal cortices. Our findings are consistent with (a) previous suggestions of susceptibility of PPI to cognitive processes controlled in a 'top down' manner by the cortex and (b) the hypothesis that compromised neural resources in the frontal cortex contribute to reduced PPI in schizophrenia.  相似文献   
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