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21.
阿尔茨海默病(A D )是最常见的一种痴呆症,主要临床特点为进行性认知功能下降,最终导致身体机能的下降甚至死亡,65岁以上的老年人群多发[1]。对于年轻家族性AD患者而言,AD的发生与多基因因素相关,而对于年老的散发性AD患者,其原因是多重性的,包括基因、环境和后天造成的基因改变等因素。尽管AD的病因不明,但患者脑内β-淀粉样蛋白(Aβ)的增多可能是导致此病的首要原因。Aβ主要是由β-淀粉样前体(APP )在β-分泌酶(BACE1)的作用下使其在β位点发生裂解而产生,这一过程在AD的病理性神经纤维缠结和淀粉样斑块形成中发挥着重要作用[2]。AD患者中BACE1的表达和活性均有显著升高[3],已成为诊断AD的一个重要生物指标[4]。而关于BACE1的了解目前还存在很多局限,现通过以下几个方面来讨论近年BACE1在AD中的有关研究进展。  相似文献   
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目的 母亲血清中微小RNA(microRNA,miRNA)的发现为无创性产前诊断开辟了新途径.但是对神经管缺陷胎儿母亲血清中妊娠相关的miRNA的研究甚少.该文旨在研究微小RNA-423(mi-croRNA-423,miR-423)在神经管缺陷胎儿孕妇血清中的异常表达及其作为潜在诊断标志物的临床价值.方法 33例产前超声检查确诊为胎儿神经管缺陷的患儿为研究对象,其中脊柱裂22例,无脑儿11例;33例胎儿健康孕妇为对照组.所有孕妇均于清晨空腹抽外周静脉血5ml离心后取血清,提取血清总RNA,用Real-time RT-PCR方法测定miR-423表达水平.并用ROC曲线分析用miR-423诊断胎儿神经管缺陷的价值.结果 神经管缺陷胎儿孕妇血清中miR-423含量(0.96±0.14)明显低于健康胎儿孕妇对照组(2.28±0.43),P<0.05.ROC分析miR-423曲线下面积为0.711(95% CI:0.566~0.856)(P<0.05).另外,对不同类型的神经管缺陷孕妇血清中的miR-423表达水平分析发现,只有在无脑儿中表达降低(0.58±0.08)差异有统计学意义.结论 孕妇血清中miR-423可作为胎儿神经管缺陷的无创性产前诊断标志物,具有潜在的临床价值,可能预示胎儿神经管缺陷严重程度.  相似文献   
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BackgroundHigh levels of interleukin 17 are expressed in active Behcet’s disease (BD) patients. High miRNA-499 relative expression is known to be associated with vascular manifestations and aneurysms in BD.Aim of the workTo detect miRNA-499 relative expression and interleukin 17 serum levels in BD patients and find their association to clinical characteristics and disease activity.Patients and methodsBlood samples were obtained from 40 Egyptian BD patients and 40 matched controls. The BD current activity form (BDCAF) was estimated. Relative expression of miRNA-499 was measured by real-time polymerase chain reaction. Serum IL-17 was also measured in by enzyme-linked immunosorbent assay.ResultsThe mean age of the patients was 34.4 ± 10.9 years, disease duration was 8.9 ± 0.8 years and age at onset was 25.5 ± 7.2 years and they were 33 males and 7 females. All patients had oral ulcers, 85% had genital ulcers and 75% had ocular manifestations. The mean BDCAF was 1.54 ± 1.78. Levels of miRNA-499 relative expression were significantly higher in BD cases versus controls (4.2 ± 2.1 vs. 1.1 ± 0.3ΔΔCt respectively; p < 0.001). Levels of IL 17 were significantly higher in BD cases versus controls (86.9 ± 31.2 vs. 34.7 ± 4.4 pg/ml respectively; p < 0.001). There was a non-significant correlation between miRNA and IL 17 in patients (r = −0.06, p < 0.71). IL17 was significantly associated only with the occurrence of arthritis (p = 0.03). There was no significant association between miRNA-499 or IL-17 with the BDCAF (r = 0.22, p = 0.12 and r = −0.002, p = 0.99; respectively).ConclusionMicro RNA-499 relative expression and IL17 levels were significantly higher in BD patients compared to the controls.  相似文献   
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Atherosclerosis is a chronic inflammatory disorder of the vasculature and is the primary cause of cardiovascular disease(CVD). CVD is currently the world's leading cause of death and the numbers are predicted to rise further because of a global increase in risk factors such as diabetes and obesity. Current therapies such as statins have had a major impact in reducing mortality from CVD. However, there is a marked residual CVD risk in patients on statin therapy. It is therefore important to understand the molecular basis of this disease in detail and to develop alternative novel therapeutics. Interferon-γ(IFN-γ) is a pro-inflammatory cytokine that is often regarded as a master regulator of atherosclerosis development. IFN-γ is able to influence several key steps during atherosclerosis development, including pro-inflammatory gene expression, the recruitment of monocytes from the blood to the activated arterial endothelium and plaque stability. This central role of IFN-γ makes it a promising therapeutic target. The purpose of this editorial is to describe the key role IFN-γ plays during atherosclerosis development, as well as discuss potential strategies to target it therapeutically.  相似文献   
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微小RNA(miRNA)是一类高度保守的内源性小分子RNA。miRNA主要通过选择性结合mRNA调控基因表达。目前研究结果表明,中枢神经系统存在大量miRNA,并参与神经细胞的正常生长、发育,以及组织损伤修复、肿瘤发生、神经退行性变等多种病理、生理过程。笔者拟就新生儿缺血缺氧性脑病(HIE) miRNA谱系的最新研究进展进行阐述,探讨其miRNA特异性表达,对新生儿HIE诊断和预后判断的意义,旨在为该病的相关诊治研究提供参考。  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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