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MicroRNA (miRNA) is an important regulator of cellular proliferation, differentiation and death. Leukemia-specific signature of miRNAs suggests that epigenetic dysregulation of miRNAs is important for leukemogenesis. We focused on the role of DNA methylation of miR-203 which targets BCR-ABL1 mRNA. The microarray analysis showed that 48 miRNAs of CpG-rich 212 miRNAs were upregulated over 2-fold after imatinib treatment. Imatinib induced the demethylation of the miR-203 promoter region, resulting in low expression of targeted BCR-ABL1 gene, and loss of proliferation of leukemic cells. In conclusion, demethylation of miR-203 is one of the molecular mechanisms of imatinib-induced inhibition of BCR-ABL1-positive leukemic cells.  相似文献   
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Objective: To research the silence of NBS1 after transfection microRNA expressing eukaryotic recombinants and the changes of telomerase activation in telomerase-positive cell line Hela. Methods: According to the sequence of NBS1 mRNA, the NBS1 pre-microRNA was designed and synthesized, then cloned into the GFP reporter pcDNA6.2-GW/EmGFP-miR vector and transfected into Hela cells. The integrity of the insert fragment was verified through colony PCR and sequencing analysis. The NBS1 gene expression of NBS1 microRNA recombinants was detected by Real-Time PCR and western blot. Telomerase activity in Hela cells was assayed by TRAP-PCR-EB. Results: Sequences of insert fragment in microRNA expressing recombinants were correct. The NBS1 gene expression was decreased, and the telomerase activation of Hela cell reduced. Conclusion: NBS1 microRNA inhibits NBS1 gene expression, and depresses telomerase activation of Hela cells. This confirms that there is relevance between NBS 1 gene and telomerase activity.  相似文献   
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Background:First-line treatments for metastatic pancreatic cancer are chemotherapy regimens consisting of 5-fluorouracil or gemcitabine; however, there are no biomarkers to help determine which patients might benefit from which treatment regimens. We aimed to show that microRNAs let-7c and 7d can be used as independent predictive biomarkers for metastatic pancreatic cancer.Methods:A total of 55 patients who had first-line chemotherapy with FOLFIRINOX or gemcitabine + capecitabine were included. Patients were divided into groups based on let-7c and let-7d levels and chemotherapy treatment as let-7c-7d high FOLFIRINOX, let-7c-7d high gemcitabine + capecitabine, let-7c-7d low FOLFIRINOX, and let-7c-7d low gemcitabine + capecitabine. Blood samples were taken from patients before chemotherapy for microRNA let-7c and 7d analysis. MicroRNA isolation was performed using a miRNeasy Serum/Plasma Kit and identified using spectrophotometric measurements. After isolation, microRNA was converted to cDNA using a microRNA cDNA Synthesis Kit with poly (A) polymerase tailing. The expression of microRNA was examined using quantitative real-time polymerase chain reaction.Results:The overall survival of patients who received FOLFIRINOX treatment with a high let-7c-7d level was statistically significantly longer than those who received gemcitabine + capecitabine with a high let-7c-7d level. In addition, patients with low let-7c expression receiving FOLFIRINOX progressed significantly 2.104 times earlier than patients with high let-7c expression receiving FOLFIRINOX.Conclusion:The serum MicroRNA let-7c level was found to be an independent predictive biomarker in the FOLFIRINOX treatment group.  相似文献   
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目的:应用基因芯片技术筛选结肠癌耐药相关微小RNAs (miRNAs),探究miRNAs对化疗耐药的调控机制。方法:采用基因芯片技术分析结肠癌细胞系HCT8及其耐长春新碱细胞系HCT8/v中miRNAs的表达差异,对部分差异表达的miRNAs应用RT-qPCR进行验证,对表达差异显著的miRNAs进行靶基因预测,利用Gene Ontology (GO)和京都基因与基因组百科全书(KEGG)数据库对预测到的靶基因进行生物信息学分析。结果:筛选出342个差异表达miRNAs,其中190个表达上调,152个表达下调。RT-qPCR验证结果示miR-125-5p、miR-181c-5p和miR-153-3的表达情况和芯片检测结果一致;miR-130a-3p和miR-149-3p的表达与芯片检测结果不一致。GO分析结果显示,耐药相关基因主要富集的旁路是RNA聚合酶II调控区序列特异性DNA结合旁路,主要通过正向调节发挥作用,位置主要是在细胞内有界细胞器上。KEGG分析结果显示,耐药相关基因最为富集的是轴突导向通路、胰岛素信号通路及磷脂酶D信号通路。结论:miRNAs与结肠癌化疗耐药密切相关。对这...  相似文献   
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<正>心血管疾病(cardiovascular diseases,CVD)是全球高发性疾病,其中冠心病(coronary heart disease,CHD)是世界范围内的主要死亡原因,在老年人群中死亡率和发病率不断上升[1],与微小RNA(microRNA,miRNA,miR)的调节密切相关[2]。研究报道,miRNA调节大量信号通路,可通过外泌体(exosome)实现细胞间传递,参与细胞间的信息交流[3],其严格  相似文献   
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外泌体是活细胞分泌至细胞外基质的纳米级囊泡,在细胞之间的物质交换和信号转导方面发挥重要作用,能将其携带的脂质、蛋白质、核酸传递至受体细胞,调节受体细胞的生理、病理过程。微小RNA(microRNA、miRNA)作为外泌体中重要的"货物"被转运至受体细胞,调控受体细胞信号通路,从而对疾病的进展起着调节的作用。近年来,外泌体miRNA在牙周疾病、黏膜相关疾病、口腔癌等疾病中的研究日益增多。本文就外泌体miRNA在口腔疾病中的调控机制进行综述,并讨论外泌体miRNA作为生物标志物在口腔疾病诊断中的潜在前景。  相似文献   
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Mammalian cardiomyocytes (CMs) maintain a low capacity for self-renewal in adulthood, therefore the induction of CMs cycle re-entry is an important approach to promote myocardial repair after injury. Recently, photobiomodulation (PBM) has been used to manipulate physiological activities of various tissues and organs by non-invasive means. Here, we demonstrate that conditioned PBM using light-emitting diodes with a wavelength of 630 nm (LED-Red) was capable of promoting the proliferation of neonatal CMs. Further studies showed that low-power LED-Red affected the expression of miR-877-3p and promoted the proliferation of CMs. In contrast, silencing of miR-877-3p partially abolished the pro-proliferative actions of LED-Red irradiation on CMs. Mechanistically, GADD45g was identified as a downstream target gene of miR-877-3p. Conditioned LED-Red irradiation also inhibited the expression of GADD45g in neonatal CMs. Moreover, GADD45g siRNA reversed the positive effect of LED-Red on the proliferation of neonatal CMs. Taken together, conditioned LED-Red irradiation increased miR-877-3p expression and promoted the proliferation of neonatal CMs by targeting GADD45g. This finding provides a new insight into the role of LED-Red irradiation in neonatal CMs biology and suggests its potential application in myocardial injury repair.  相似文献   
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Breast cancer, the most common cancer among women, is a heterogeneous and complex disease, which detail of its precise progression mechanisms is less understood. So, an improved comprehension of the precise molecular mechanisms leading to disease progression and design of effective targeted therapies are required for patients with breast cancer. MicroRNAs demonstrate an uncovered class of small and endogenous non-coding RNAs and play an important role in the normal biological processes, including cell differentiation, proliferation and apoptosis. Some miRNAs, known as oncomiR, show different expression levels in cancer and are capable to effect on cellular transformation, carcinogenesis and metastasis and are characterized by high expression levels in tumors compared to normal tissues. Therefore, oncomiRs can be considered as prognostic biomarkers and therapeutic targets in different types of cancers. Moreover, the utilization of oncomiRs as therapeutic targets for cancer is promising. Accordingly, there is evidence which implies an important role of various oncogenic microRNAs in immunopathogenesis of breast cancer. In this review we will discuss about the role of various oncomiRs such as miR-21, miR-155, miR-10b, and miR-221/222 in the pathogenesis and treatment of breast cancer.  相似文献   
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主动脉夹层(aortic dissection,AD)是一种由于中层退行性变导致的极其凶险的主动脉疾病,死亡率及并发症率高居不下。目前越来越多研究证明,MicroRNA在主动脉夹层中发病机制中起重要的调控作用。本文就MicroRNA对血管平滑肌细胞、细胞外基质、血管炎症及粥样硬化及黏着斑等的影响,与主动脉夹层发病的关系做一综述。  相似文献   
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