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71.
目的:探讨lncRNA 178030.2通过TRPS1对三阴性乳腺癌细胞紫杉醇耐药的影响与机制。方法:采用逐步增加剂量间歇作用的方法诱导三阴性乳腺癌紫杉醇耐药细胞系并命名为MDA-MB-231/R。采用定量PCR和Western blot检测耐药细胞和亲本细胞中lncRNA 178030.2和TRPS1的表达;应用Lipofectamine 2000将lncRNA 178030.2高表达质粒pcmv-178030.2和对照质粒pcmv转染至MDA-MB-231细胞,分别为高表达组和对照组,定量PCR检测lncRNA 178030.2水平的变化,分别用定量PCR和Western blot检测TRPS1 mRNA及蛋白水平的变化;RIP实验检测lncRNA 178030.2是否与TRPS1相结合;MTT法检测MDA-MB-231细胞对紫杉醇的敏感性及细胞增殖。应用Lipofectamine 2000将lncRNA 178030.2小干扰RNA si178030.2和对照siNC转染至MDA-MB-231/R细胞,分别为干扰组和对照组,定量PCR检测lncRNA 178030.2水平的变化,分别用定量PCR和Western blot检测TRPS1 mRNA及蛋白水平的变化;MTT法检测MDA-MB-231/R细胞对紫杉醇的敏感性及细胞增殖。应用Lipofectamine 2000将TRPS1过表达质粒pcmv-TRPS1和对照质粒pcmv转染至MDA-MB-231细胞,分别为高表达组和对照组,分别用定量PCR和Western blot检测两组细胞中TRPS1 mRNA及蛋白水平的表达情况,然后再分别应用Lipofectamine 2000将lncRNA 178030.2高表达质粒pcmv-178030.2转染入两组细胞,MTT法检测MDA-MB-231细胞对紫杉醇的敏感性及细胞增殖。结果:成功构建在3 μg/ml紫杉醇中稳定生长的三阴性乳腺癌耐药细胞系MDA-MB-231/R。定量PCR结果显示:lncRNA 178030.2在紫杉醇耐药细胞系MDA-MB-231/R中的表达明显高于在其亲本细胞MDA-MB-231中的表达;定量PCR和Western blot显示:TRPS1 mRNA和蛋白在紫杉醇耐药细胞系MDA-MB-231/R中的表达明显低于在其亲本细胞系MDA-MB-231中的表达;与对照组相比,高表达lncRNA 178030.2组的MDA-MB-231细胞中TRPS1表达下降,细胞对紫杉醇的敏感性降低,细胞增殖增强,且lncRNA 178030.2确实可以与TRPS1相结合;与对照组相比,低表达lncRNA 178030.2组的MDA-MB-231/R细胞中TRPS1表达升高,细胞对紫杉醇的敏感性升高,细胞增殖减弱;在MDA-MB-231细胞中过表达TRPS1后再过表达lncRNA 178030.2,其促进紫杉醇耐药、促进细胞增殖的作用也明显减弱。结论:lncRNA 178030.2促进三阴性乳腺癌细胞MDA-MB-231的紫杉醇耐药,促进细胞增殖,其发生机制可能与下调TRPS1的表达有关。  相似文献   
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Pancreatic ductal adenocarcinoma (PDAC) remains a leading cause of cancer-related death due to the failure of traditional therapies. In the present study, we attempted to construct a lncRNA-miRNA-mRNA network which may modulate PDAC cell proliferation and Gemcitabine-induced cell apoptosis starting from CDK14, a new member of the CDK family and an oncogene in many cancers. Based on TCGA data, a significant positive correlation was observed between lncRNA MSC-AS1 and CDK14. Moreover, MSC-AS1 expression was upregulated in PDAC tissues. Higher MSC-AS1 expression was correlated with poorer prognosis in patients with PDAC. MSC-AS1 knockdown in Panc-1 and BxPC-3 cells significantly inhibited the cell proliferation. Moreover, miR-29b-3p, which has been reported to act as a tumor suppressor, was predicted to bind to both MSC-AS1 and CDK14. Contrary to MSC-AS1, higher miR-29b-3p expression was correlated to better prognosis in patients with PDAC. In both PDAC cell lines, miR-29b-3p negatively regulated MSC-AS1 and CDK14. As confirmed using luciferase reporter gene and RIP assays, MSC-AS1 served as a ceRNA for miR-29b-3p to counteract miR-29b-mediated CDK14 repression. MSC-AS1 knockdown inhibited CDK14 protein levels and PDAC proliferation and enhanced gemcitabine-induced cell death and apoptosis while miR-29b-3p inhibition exerted an opposing effect; the effect of MSC-AS1 knockdown was partially attenuated by miR-29b-3p inhibition. Taken together, we demonstrated that MSC-AS1/miR-29b-3p axis modulates the cell proliferation and GEM-induced cell apoptosis in PDAC cell lines through CDK14. We provided a novel experimental basis for PDAC treatment from the perspective of lncRNA-miRNA-mRNA network.  相似文献   
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目的探究尿液外泌体长链非编码RNA前列腺癌相关转录本1(lncRNA PCAT-1)评估非浸润性膀胱癌患者复发的价值。方法随机选取2015年1月—2016年3月进行治疗的非浸润性膀胱癌患者50例作为非浸润性膀胱癌组,选取同期在进行健康体检的健康受检者50例作为对照组。测定两组尿液外泌体中lncRNA PCAT-1表达情况。分析尿液外泌体lncRNA PCAT-1表达与临床病理参数的相关性、尿液外泌体lncRNA PCAT-1与尿液脱落细胞学对非浸润性膀胱癌的诊断价值、影响非浸润性膀胱癌患者复发的相关因素,评估非浸润性膀胱癌复发的价值及尿液外泌体lncRNA PCAT-1表达与非浸润性膀胱癌患者预后的关系。结果与对照组比较,非浸润性膀胱癌组患者尿液外泌体lncRNA PCAT-1表达水平明显升高(P<0.01)。尿液外泌体lncRNA PCAT-1表达与病理分期具有明显相关性(P<0.01)。尿液外泌体lncRNA PCAT-1诊断非浸润性膀胱癌的曲线下面积明显高于尿液脱落细胞学。采用Cox比例风险因素回归模型分析,病理分期及lncRNA PCAT-1均为影响非浸润性膀胱癌患者复发的独立危险因素。以尿液外泌体lncRNA PCAT-1相对表达量5.14±1.04分为高表达组(23例)与低表达组(27例),Kaplan-Meier生存曲线分析结果显示,lncRNA PCAT-1低表达量组生存期明显高于lncRNA PCAT-1高表达组。结论外泌体lncRNA PCAT-1在非浸润性膀胱癌患者尿液中的表达水平较健康受检者明显升高,且其表达水平与患者病理分期明显相关。尿液外泌体lncRNA PCAT-1对评估非浸润性膀胱癌患者的复发具有重要作用。  相似文献   
75.
GBM (glioblastoma multiforme) is the most malignant form of glioma and is the most commonly occurring primary malignant brain tumour. GBM is difficult to completely excise, resulting in an extremely high recurrence rate. The occurrence of an aggressive glioma phenotype depends on EMT (epithelial-mesenchymal transformation), in which epithelial cells transform into mesenchymal cells by losing their cell-cell adhesion and polarity. NcRNAs (non-coding RNAs) play a significant role in the cellular progression from a normal phenotype to a cancerous phenotype. Recently, many studies have shown that there are two essential regulatory ncRNAs, miRNAs (microRNAs) and lncRNAs, which are closely related to EMT. In this review, we conducted a comprehensive investigation of the dysregulated lncRNAs and miRNAs in gliomas with particular attention to the function and regulatory mechanisms of several important lncRNAs and miRNAs, and we discussed their roles as glioma diagnostic and prognostic biomarkers and their potential clinical applications as therapeutic targets.  相似文献   
76.
Brain glioma is the most common malignant tumor of the central nervous system, and one of the leading causes of death in patients with intracranial tumors. The clinical outcome of glioma is usually poor due to abundant vascularity, fast growth and susceptibility of invasion to normal brain tissues. Our microarray study showed that lncRNA-LINC01116 was significantly upregulated in glioma tissues and played an important role in cell proliferation, cycle, migration, invasion and angiogenesis. In addition, vascular endothelial growth factor (VEGFA) may be the major target genes in the downstream of lncRNA-LINC01116. Dual luciferase assay showed that LINC01116 and VEGFA both contained a miR-31-5p binding site, and LINC01116 could regulate the expression of VEGFA through competitive absorption of miR-31-5p. RNA immunoprecipitation indicated that LINC01116 and VEGFA were present in the miR-31-5p-RISC complex, and biotinylated miR-31-5p pull-down assay suggested that there was a competitive relationship between LINC01116 and VEGFA to bind with miR-31-5p. Collectively, our study has identified a novel lncRNA-LINC01116 and clarified the role and mechanism of LINC01116 in the tumorigenesis of glioma. LINC01116 may prove to be a potential target for the clinical diagnosis and treatment of glioma.  相似文献   
77.
目的:分析LINC00473在胃癌中的表达情况、临床意义及对人胃癌细胞增殖水平的影响。方法:利用癌症基因组图谱(TCGA)数据库下载胃腺癌相关数据集,分析肿瘤组织与正常组织之间LINC00473的表达差异;利用 Kaplan-Meier 曲线进行患者生存分析;MTT方法检测胃癌细胞增殖水平、流式细胞术检测凋亡率的改变。结果:与癌旁组织比较,LINC00473在胃癌组织中的表达明显增加,差异具有统计学意义(P<0.05);生存分析发现,LINC00473表达与胃癌患者OS和DFS时间相关,LINC00473高表达的胃癌患者,OS和DFS时间明显缩短(P<0.05)。转染LINC00473 siRNA至胃癌细胞后,结果发现与阴性质粒转染组比较:转染siRNA-LINC00473的胃癌细胞,LINC00473 表达明显降低;LINC00473表达下调后细胞增殖水平减慢,凋亡率增加。结论:LINC00473是一个新的胃癌生物标记物,可作为潜在的治疗新靶点。  相似文献   
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宋洋  任芳 《现代肿瘤医学》2020,(14):2365-2369
目的:探讨miR-590-5p在卵巢癌组织中的表达情况以及其对卵巢癌细胞增殖的影响及作用机制。方法:Real-time PCR和双荧光素酶实验确定miR-590-5p与lncRNA SNHG1之间的调控作用。Real-time PCR检测卵巢癌、癌旁组织以及卵巢癌细胞中miR-590-5p的表达。分别采用NC mimic或者miR-590-5p mimic转染两株卵巢癌细胞,CCK-8检测各组细胞的增殖情况。此外,Real-time PCR检测两株细胞中SOX2、RECK和YAP1的表达。结果:Real-time PCR结果显示下调SNHG1后miR-590-5p的表达显著升高。双荧光素酶结果显示转染miR-590-5p mimic和野生型SNHG1片段的细胞中荧光素酶的活性显著降低。此外,Real-time PCR结果显示miR-590-5p在卵巢癌组织中的表达水平显著低于癌旁组织。CaOV3、OV-90细胞中miR-590-5p的表达水平明显低于其他卵巢癌细胞。转染miR-590-5p mimic显著上调了CaOV3、OV-90细胞中miR-590-5p的表达并且抑制了这两株细胞的增殖,同时抑制了两株细胞中SOX2、RECK和YAP1的表达。结论:miR-590-5p的低表达与卵巢癌的进展密切相关,miR-590-5p能够介导SNHG1信号并且通过对其下游靶基因的调控抑制卵巢癌细胞的增殖。  相似文献   
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