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51.
目的检测前列腺癌组织及良性前列腺组织中微RNA-374b表达,探讨其与前列腺癌恶性程度及生化复发的关系。方法收集广州医科大学附属广州市第一人民医院、中山大学附属第二医院、广州市红十字会医院2000年至2010年泌尿外科103例前列腺癌手术后的样本和25例前列腺增生手术获取的前列腺良性组织样本。采用原位杂交技术检测微RNA.374b在前列腺癌组织及良性前列腺组织中表达,并对微RNA.374b表达与前列腺癌患者年龄、术前PSA、临床分期、病理分期、Gleason评分、是否生化复发、是否转移及是否死亡的关系进行统计分析。根据微RNA.374b的相对表达量,以中位数(M=4.50)将其分为低表达组及高表达组,运用Kaplan.meier方法及Log.rank检验进行总体生存率和无生化复发生存率分析。结果微RNA.374b在前列腺癌的表达低于良性组织(3.97±1.17比4.70±0.71,P〈0.05)。微RNA.374b的表达量同Gleason评分、病理分期、转移、是否生存及生化复发有关(均P〈0.05),同年龄、PSA水平及临床分期无关(均P〉0.05)。微RNA.374b低表达组无生化复发生存率低于高表达组(P〈0.05),高表达组的生化复发时间高于低表达组(P〈0.05)。微RNA.374b表达与总体生存率无关。结论微RNA.374b的低表达与前列腺癌恶性程度有关,有望成为评价前列腺癌恶性程度及生化复发的指标。  相似文献   
52.
MicroRNAs (miRNAs) are small noncoding RNA molecules of 18–25 nucleotides in length that regulate gene expression involved in fundamental cell processes. The induction and chronification of pain is associated with many expressional changes in pain-related proteins. miRNA has the potential to regulate gene and protein expression associated with the induction and chronification of pain. Thus, miRNAs might have promise in therapy and as a diagnostic and prognostic biomarker in pain medicine. The application of miRNA has been an emerging field in pain research in recent years. Many studies focusing on the regulation of miRNAs under different tissue and nociceptive stimuli have been performed in recent years. In this review, we intend to introduce the most recent research in the field of miRNA related with pain medicine such as the expression and function of miRNA in different animal pain model, the challenge of application and delivery of miRNA in vivo, the potential toxic effects of miRNA and future problems in clinical application that need to be resolved. This review focuses on the results of miRNA in animal studies and the prospect for future success.  相似文献   
53.
ABSTRACT: BACKGROUND: Lung cancer is the major cause of cancer death globally, it is often diagnosed at an advanced stage and has one of the lowest survival rates of any type of cancer. The common interest in the field of lung cancer research is the identification of biomarkers for early diagnosis and accurate prognosis. There is increasing evidence to suggest that microRNAs play important and complex roles in lung cancer. METHODS: A meta-analysis was conducted to review the published microRNA expression profiling studies that compared the microRNAs expression profiles in lung cancer tissues with those in normal lung tissues. A vote-counting strategy that considers the total number of studies reporting its differential expression, the total number of tissue samples used in the studies and the average fold change was employed. RESULTS: A total of 184 differentially expressed microRNAs were reported in the fourteen microRNA expression profiling studies that compared lung cancer tissues with normal tissues, with 61 microRNAs were reported in at least two studies. In the panel of consistently reported up-regulated microRNAs, miR-210 was reported in nine studies and miR-21 was reported in seven studies. In the consistently reported down-regulated microRNAs, miR-126 was reported in ten studies and miR-30a was reported in eight studies. Four up-regulated microRNAs (miR-210, miR-21. miR-31 and miR-182) and two down-regulated mcroiRNAs (miR-126 and miR-145) were consistently reported both in squamous carcinoma and adenocarcinoma-based subgroup analysis, with the other 14 microRNAs solely reported in one or the other subset. CONCLUSIONS: In conclusion, the top two most consistently reported up-regulated microRNAs were miR-210 and miR-21. The results of this meta-analysis of human lung cancer microRNA expression profiling studies might provide some clues of the potential biomarkers in lung cancer. Further mechanistic and external validation studies are needed for their clinical significance and role in the development of lung cancer.  相似文献   
54.
微小RNA(miRNA)是一类小分子的非编码调控的单链RNA,它参与有机体的生长、发育等多种生理过程.近年来研究表明肿瘤组织具有不同的miRNA表达,异常表达的miRNA影响了肿瘤细胞的发生、进展、分化、转移和复发.miRNA的不同表达不仅有助于肿瘤组织的诊断,而且可以指导预后.针对miRNA为靶点的动物学研究也发现,干扰某种miRNA表达可以减小肿瘤体积,抑制腹膜转移而发挥治疗作用.  相似文献   
55.
目的:探讨miR-362-3p在胆囊癌中的表达及功能。方法:用qRT-PCR检测手术切除的44例胆囊癌患者手术标本中miR-362-3p的表达,并分析其表达与胆囊癌临床病理特征及预后的关系。miR-362-3p模拟物转染胆囊癌细胞后,分别用MTT法、细胞划痕试验及Transwell侵袭试验观察细胞增殖、迁移及侵袭的改变。通过生物信息学方法及双荧光素酶报告基因试验分析miR-362-3p的靶基因,并采用补救试验验证。结果:miR-362-3p在胆囊癌组织的表达明显低于相应癌旁组织(P0.05)。miR-362-3p的低表达与肿瘤TNM分期、淋巴结转移及远处转移明显有关(均P0.05)。低表达miR-362-3p患者总体生存率较高表达miR-362-3p患者明显降低(P0.05)。转染miR-362-3p模拟物后,胆囊癌细胞的增殖,迁移及侵袭能力明显减弱(均P0.05)。Nemo样激酶(NLK)被确定为miR-362-3p的潜在靶基因,转染NLK过表达载体后,miR-362-3p模拟物对胆囊癌细胞的上述作用被明显逆转(均P0.05)。结论:miR-362-3p在胆囊癌中表达下调,下调的miR-362-3p减少了对靶基因NLK的抑制,从而促进了胆囊癌细胞的增殖、迁移和侵袭。  相似文献   
56.
目的 探讨miR-143/145侧翼序列rs4705342和rs4705343多态性与膀胱癌遗传易感性的关系。方法 采用基于医院的病例对照研究,收集106例膀胱癌患者和162例对照人群外周静脉血样本,TaqMan探针法和聚合酶链反应-限制性长度片段多态性分析rs4705342和rs4705343多态性。结果 rs4705342位点CC基因型和C等位基因显著降低了膀胱癌的发病风险(CC与TT相比,调整OR=0.30,95%CI:0.10~0.88,P=0.018;C与T相比,调整OR=0.60,95%CI:0.40~0.89,P=0.01)。 单倍型分析显示,rs4705342C-rs4705343T单倍型显著降低了膀胱癌的发病风险(OR=0.33,95%CI:0.15~0.74)。结论 miR-143/145侧翼序列rs4705342CC基因型可能是膀胱癌发病的保护因素。  相似文献   
57.
目的探寻调节青少年特发性脊柱侧凸(AIS)患者椎旁肌改变的关键微RNA(miRNA)。方法对3例女性AIS患者凹侧与凸侧椎旁肌组织进行RNA高通量测序,获得差异表达miRNA。使用27例AIS手术患者的椎旁肌组织采用实时荧光定量PCR法验证测序的质量和差异,并将miRNA的相对差异表达量与患者临床参数进行相关性分析。结果 AIS患者凹侧与凸侧椎旁肌组织存在18个差异表达miRNA。实时荧光定量PCR法检测结果显示,miR-516、miR-517、mi R-495的表达差异具有统计学意义(P 0.05)。两侧椎旁肌miR-516相对表达量差值与患者发病年龄呈负相关(r=-0.452),miR-517相对表达量差值与侧凸Cobb角呈负相关(r=-0.378)。结论 AIS患者两侧椎旁肌miR-516、miR-517、miR-495存在不对称表达,其中miR-516、miR-517的不对称表达与发病年龄和侧凸角度相关。  相似文献   
58.
BACKGROUND: Long-term excessive intake of fluoride, especially through drinking water, can cause chronic fluorosis of bone. The disease can lead to bone damage and deformity, and is difficult to recover. Unfortunately, we have not developed a noninvasive or minimally invasive method for its early diagnosis. OBJECTIVE: To observe the expression of apoptosis-related miRNAs under the action of excessive fluorine in human osteoblasts. METHODS: The fluorine model was established in the human osteoblasts by cultured with 20 and 40 mg/L sodium fluoride for 24 and 48 hours, respectively. The expression levels of apoptosis-related miRNAs were determined by PCR array. RESULTS AND CONCLUSION: After 24-hour treatment of sodium fluoride, 48 kinds of miRNAs were upregulated and 4 ones were down-regulated in the osteoblasts. After 48-hour treatment of sodium fluoride, 21 kinds of miRNAs were upregulated and 2 ones were down-regulated. It showed that nine up-regulated miRNAs and one down-regulated miRNA were same in two periods. The 10 miRNAs are selected for target gene analysis on bioinformatics software that refer to the effect of anti-apoptosis and pro-apoptosis, which is of great significance for the early identification of skeletal fluorosis. © 2018, Journal of Clinical Rehabilitative Tissue Engineering Research. All rights reserved.  相似文献   
59.
研究背景脑源性神经营养因子(BDNF)在阿尔茨海默病(AD)发病机制中发挥重要作用,微小RNA-132(mi RNA-132)在神经元呈高表达,可以通过调控靶基因表达参与BDNF介导的神经发育过程。本研究旨在探讨阿尔茨海默病神经元模型中mi RNA-132与BDNF的调控关系和神经保护作用。方法体外培养海马神经元72 h后慢病毒转染mi RNA-132,并于体外培养第7天以β-淀粉样蛋白(Aβ)处理制备阿尔茨海默病神经元模型;实时荧光定量聚合酶链反应观察对照组与AD组mi RNA-132表达差异以及不同处理组BDNF m RNA表达变化,噻唑蓝法观察不同处理方式对细胞活性的影响。结果 (1)AD组海马神经元mi RNA-132(t=13.888,P=0.000)和BDNF m RNA(t=-12.274,P=0.000)表达水平均低于对照组。(2)原代培养的海马神经元经慢病毒转染后倒置相差荧光显微镜可见绿色荧光蛋白,对照组(t=16.135,P=0.000)和AD组(t=8.656,P=0.000)转染过表达mi RNA-132后均能上调BDNFm RNA表达。(3)AD组海马神经元活性降低(t=-6.023,P=0.000),AD组转染mi RNA-132后神经元活性增强(t=3.385,P=0.007),予以外源性BDNF共培养后神经元活性明显改善(t=3.672,P=0.004)。结论阿尔茨海默病神经元模型mi RNA-132和BDNF表达水平均下降,mi RNA-132可上调BDNF表达,提示mi RNA-132和BDNF对阿尔茨海默病神经元模型具有神经保护作用,有望为阿尔茨海默病诊断与治疗提供新的视角。  相似文献   
60.
目的探讨急性脑梗死早期外周血清中miRNAs水平与侧支循环建立的关系及临床意义。方法选择2014年1月-2015年11月在我院住院的急性脑梗死患者,根据其脑侧支循环状况,分为侧支循环良好组(42例)与不良组(28例),另设31例健康体检者为对照。比较各组间一般临床资料及梗死早期血清中一组miRNAs的分子变化,并进一步用Logistic回归分析miRNAs水平与梗死患者侧支循环建立的关系。结果血清中抑制血管新生的MIR-15b、MIR-92a及促血管新生的MIR-126、MIR-132和MIR-210水平在侧支循环良好、不良组及对照组间存在差异表达,部分特异性miRNAs分子组间比较有显著性差异(P0.05,P0.01);Logistic回归显示,这些抑制或促血管新生的miRNAs,特别是促血管新生的MIR-126、MIR-132和MIR-210是急性脑梗死侧支循环建立好坏的影响因素。结论早期血清中一组特异性miRNAs分子可能作为一种预测急性脑梗死患者脑内侧支循环状况的便捷指标。  相似文献   
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