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91.

Introduction

Cystic fibrosis (CF) is a multi-organ disorder characterized by chronic sino-pulmonary infections and inflammation. Many patients with CF suffer from repeated pulmonary exacerbations that are predictors of worsened long-term morbidity and mortality. There are no reliable markers that associate with the onset or progression of an exacerbation or pulmonary deterioration. Previously, we found that the Mirc1/Mir17–92a cluster which is comprised of 6 microRNAs (Mirs) is highly expressed in CF mice and negatively regulates autophagy which in turn improves CF transmembrane conductance regulator (CFTR) function. Therefore, here we sought to examine the expression of individual Mirs within the Mirc1/Mir17–92 cluster in human cells and biological fluids and determine their role as biomarkers of pulmonary exacerbations and response to treatment.

Methods

Mirc1/Mir17–92 cluster expression was measured in human CF and non-CF plasma, blood-derived neutrophils, and sputum samples. Values were correlated with pulmonary function, exacerbations and use of CFTR modulators.

Results

Mirc1/Mir17–92 cluster expression was not significantly elevated in CF neutrophils nor plasma when compared to the non-CF cohort. Cluster expression in CF sputum was significantly higher than its expression in plasma. Elevated CF sputum Mirc1/Mir17–92 cluster expression positively correlated with pulmonary exacerbations and negatively correlated with lung function. Patients with CF undergoing treatment with the CFTR modulator Ivacaftor/Lumacaftor did not demonstrate significant change in the expression Mirc1/Mir17–92 cluster after six months of treatment.

Conclusions

Mirc1/Mir17–92 cluster expression is a promising biomarker of respiratory status in patients with CF including pulmonary exacerbation.  相似文献   
92.

Introduction

Bladder cancer (BC) is diagnosed by cystoscopy, which is invasive, costly and causes considerable patient discomfort. MicroRNAs (miR) are dysregulated in BC and may serve as non-invasive urine markers for primary diagnostics and monitoring. The purpose of this study was to identify a urinary miR signature that predicts the presence of BC.

Methods

For the detection of potential urinary miR markers, expression of 384 different miRs was analyzed in 16 urine samples from BC patients and controls using a Taqman? Human MicroRNA Array (training set). The identified candidate gene signature was subsequently validated in an independent cohort of 202 urine samples of patients with BC and controls with microscopic hematuria. The final miR signature was developed from a multivariable logistic regression model.

Results

Analysis of the training set identified 14 candidate miRs for further analysis within the validation set. Using backward stepwise elimination, we identified a subset of 6 miRs (let-7c, miR-135a, miR-135b, miR-148a, miR-204, miR-345) that distinguished BC from controls with an area under the curve of 88.3%. The signature was most accurate in diagnosing high-grade non-muscle invasive BC (area under the curve?=?92.9%), but was capable to identify both low-grade and high-grade disease as well as non-muscle and muscle-invasive BC with high accuracies.

Conclusions

We identified a 6-gene miR signature that can accurately predict the presence of BC from urine samples, independent of stage and grade. This signature represents a simple urine assay that may help reducing costs and morbidity associated with invasive diagnostics.  相似文献   
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Antidepressant efficacy is insufficient, unpredictable and poorly understood in major depressive episode (MDE). Gene expression studies allow for the identification of significantly dysregulated genes but can limit the exploration of biological pathways. In the present study, we proposed a gene coexpression analysis to investigate biological pathways associated with treatment response predisposition and their regulation by microRNAs (miRNAs) in peripheral blood samples of MDE and healthy control subjects. We used a discovery cohort that included 34 MDE patients that were given 12-week treatment with citalopram and 33 healthy controls. Two replication cohorts with similar design were also analyzed. Expression-based gene network was built to define clusters of highly correlated sets of genes, called modules. Association between each module’s first principal component of the expression data and clinical improvement was tested in the three cohorts. We conducted gene ontology analysis and miRNA prediction based on the module gene list. Nine of the 59 modules from the gene coexpression network were associated with clinical improvement. The association was partially replicated in other cohorts. Gene ontology analysis demonstrated that 4 modules were associated with cytokine production, acute inflammatory response or IL-8 functions. Finally, we found 414 miRNAs that may regulate one or several modules associated with clinical improvement. By contrast, only 12 miRNAs were predicted to specifically regulate modules unrelated to clinical improvement. Our gene coexpression analysis underlines the importance of inflammation-related pathways and the involvement of a large miRNA program as biological processes predisposing associated with antidepressant response.  相似文献   
95.
MicroRNA在人结肠癌干细胞中的表达谱   总被引:1,自引:0,他引:1  
目的:探讨微小RNA(microRNA,miRNA)在人结肠癌干细胞中的表达,为进一步研究miRNA调控结肠癌干细胞向结肠癌细胞分化的分子机制奠定基础.方法:应用miRNA表达谱芯片检测人结肠癌干细胞和已分化结肠癌细胞中miRNA的表达谱.利用实时定量PCR技术检测两种细胞中差异表达的miRNA,验证miRNA芯片结果的可靠性.应用软件对筛选出的显著差异表达miRNA的靶基因进行预测.结果:与已分化结肠癌细胞相比,人结肠癌干细胞中表达上调超过1.5倍的miRNA有35个.为:hsa-miR-192,hsa-miR-29b,hsa-miR-215,hsa-miR-194,hsa-miR-33a,hsa-miR-32等:表达下调超过1.5倍的miRNA有11个,为:hsa-miR-93,hsa-miR-1231,hsa-miR-524-3p,hsa-miR-886-3p等.PCR技术验证,与miRNA芯片结果相符合.表达显著上调miRNA的共同靶mRNA有:AFF2、MTF1、RUNDC2C和ZFHX4.表达显著下调miRNA的共同靶mRNA有:ONECUT2、SH3TC2、PTPRT、RNABP10、NR3C1、RGSL1、RNASEL和TANC2.结论:筛选出的差异表达miRNA可能参与结肠癌的发病.为该病诊治提供了新的思路.其共同靶基因可能具有重要的调控结肠癌干细胞生长和分化的作用.  相似文献   
96.
 【摘要】 微小RNA (miRNA)是近年来在真核生物中发现的、在转录后水平负调控基因表达的一类长约22个核苷酸的非编码小分子RNA。miRNA生物学效应广泛,与细胞生长、凋亡、新陈代谢和信号转导等密切相关。已报道miRNA在各种肿瘤中表达失常,可能发挥着癌基因和抑癌基因的双重作用,同时越来越多的研究表明miRNA在调节肿瘤细胞对抗肿瘤药物耐药方面发挥着重要作用。系统深入地研究miRNA在肿瘤耐药中的机制,将为发展基于miRNA逆转肿瘤耐药的治疗策略提供重要的依据。  相似文献   
97.
目的:探讨从石蜡包埋组织中运用实时荧光定量PCR(RQ-PCR)方法检测microRNA表达的可靠性和敏感性。方法:选取2005年至2010年从石河子大学医学院第一附属医院、新疆伊犁哈萨克族自治州友谊医院收集的97例福尔马林固定、石蜡包埋食管癌组织样本,提取组织总RNA,RT-PCR逆转录为cDNA,实时荧光定量PCR法检测microRNA表达。结果:97例食管癌组织样本中,RNA提取成功90例,7例失败,运用实时荧光定量PCR成功检测了83例microRNA表达,7例检测不准确。RNA提取成功率明显高于失败率,实时荧光定量PCR检出的定量准确例数高于定量不准确例数,P<0.05,差异具有统计学意义。结论:实时荧光定量PCR(RQ-PCR)方法是检测石蜡包埋组织中microRNA表达的一种有效方法。  相似文献   
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100.
HLA-G is a class Ib HLA which has gained much attention due to its multiple functions on the immune system. HLA-G exerts several immunomodulatory effects, being beneficially implicated in embryo implantation and fetal survival but, conversely, being potentially detrimental in tumors and viral infections. Such a two-edged sword behavior suggest that HLA-G expression is under tight regulation. However, to date, little is known about the regulation of this gene and previous works have been unable to well correlate HLA-G regulation at the mRNA level with the polymorphic variants at the genomic level. Here we present the hypothesis that an element, which was until now neglected, might play a role in HLA-G expression regulation: MicroRNAs might participate in the regulation of the HLA-G gene expression through a putative microRNA binding site at its 3′ UTR region. Inside the 20 nt region of this microRNA binding site lies a C/G polymorphism, which was shown to be responsible for differential microRNA binding affinity and translation suppression. The role of microRNA binding on the regulation of HLA-G gene expression (and therefore on tolerance versus immune response) can be easily tested through relatively simple steps: Confirming the expression of those three complementary microRNAs in human cells which express HLA-G, followed by examination of the correlation between HLA-G mRNA and protein production controlling for HLA-G genotypes and microRNA levels; finally, selective inhibition of microRNA activity with anti-sense oligos restoring HLA-G production would access microRNA influence on HLA-G expression which, if confirmed, might help in the development of strategies to the management of several conditions in which HLA-G is involved, including pregnancy complications, transplantation, and cancer.  相似文献   
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