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彭晋  杨放春 《高技术通讯》2006,16(2):122-126
探讨了将固网软交换的特性引入到UMTS MSC Server中以增强MSC Server的能力的问题.从信令控制、媒体控制、业务交换等方面对增强的MSC Server进行了阐述和分析,在UMTS电路交换域上为实现广泛的网络融合和灵活多样的增值业务提供架构.  相似文献   
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Human umbilical-cord-derived mesenchymal stem cells (hUC-MSC) are a type of mesenchymal stem cells and are more primitive than other MSCs. In this study, we identify novel genes and signal-activating proteins involved in the neural differentiation of hUC-MSCs induced by Low-Intensity Sub-Sonic Vibration (LISSV). RNA sequencing was used to find genes involved in the differentiation process by LISSV. The changes in hUC-MSCs caused by LISSV were confirmed by PLXNA4 overexpression and gene knockdown through small interfering RNA experiments. The six genes were increased among genes related to neurons and the nervous system. One of them, the PLXNA4 gene, is known to play a role as a guide for axons in the development of the nervous system. When the PLXNA4 recombinant protein was added, neuron-related genes were increased. In the PLXNA4 gene knockdown experiment, the expression of neuron-related genes was not changed by LISSV exposure. The PLXNA4 gene is activated by sema family ligands. The expression of SEMA3A was increased by LISSV, and its downstream signaling molecule, FYN, was also activated. We suggest that the PLXNA4 gene plays an important role in hUC-MSC neuronal differentiation through exposure to LISSV. The differentiation process depends on SEMA3A-PLXNA4-dependent FYN activation in hUC-MSCs.  相似文献   
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Adenomyosis, endometriosis, endometritis, and typical endometrial hyperplasia are common non-cancerous diseases of the endometrium that afflict many women with life-impacting consequences. The mammalian target of the rapamycin (mTOR) pathway interacts with estrogen signaling and is known to be dysregulated in endometrial cancer. Based on this knowledge, we attempt to investigate the role of mTOR signaling in benign endometrial diseases while focusing on how the interplay between mTOR and eukaryotic translation initiation factors (eIFs) affects their development. In fact, mTOR overactivity is apparent in adenomyosis, endometriosis, and typical endometrial hyperplasia, where it promotes endometrial cell proliferation and invasiveness. Recent data show aberrant expression of various components of the mTOR pathway in both eutopic and ectopic endometrium of patients with adenomyosis or endometriosis and in hyperplastic endometrium as well. Moreover, studies on endometritis show that derangement of mTOR signaling is linked to the establishment of endometrial dysfunction caused by chronic inflammation. This review shows that inhibition of the mTOR pathway has a promising therapeutic effect in benign endometrial conditions, concluding that mTOR signaling dysregulation plays a critical part in their pathogenesis.  相似文献   
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The central nervous system (CNS) necessitates intricately coordinated immune responses to prevent neurological disease. However, the emergence of viruses capable of entering the CNS and infecting neurons threatens this delicate balance. Our CNS is protected from foreign invaders and excess solutes by a semipermeable barrier of endothelial cells called the blood–brain barrier. Thereby, viruses have implemented several strategies to bypass this protective layer and modulate immune responses within the CNS. In this review, we outline these immune regulatory mechanisms and provide perspectives on future questions in this rapidly expanding field.  相似文献   
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The present studies were conducted to evaluate key serum proteins and other components that mediate anchorage-independent growth (3-D growth) of LNCaP prostate cancer cells as spheroids. The cells were cultured on ultra-low attachment plates in the absence and presence of fetuin-A and with or without extracellular vesicles. The data show that fetuin-A (alpha 2HS glycoprotein) is the serum protein that mediates 3-D growth in these cells. It does so by sequestering extracellular vesicles of various sizes on the surfaces of rounded cells that grow as spheroids. These vesicles in turn transmit growth signals such as the activation of AKT and MAP kinases in a pattern that differs from the activation of these key growth signaling pathways in adherent and spread cells growing in 2-D. In the process of orchestrating the movement and disposition of extracellular vesicles on these cells, fetuin-A is readily internalized in adhered and spread cells but remains on the surfaces of non-adherent cells. Taken together, our studies suggest the presence of distinct signaling domains or scaffolding platforms on the surfaces of prostate tumor cells growing in 3-D compared to 2-D.  相似文献   
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目的:探讨槲皮素是否通过核因子E2相关因子2(nuclear factor erythroid 2-related factor 2, Nrf2)通路拮抗糖尿病大鼠胰腺氧化损伤。方法:选取SPF级SD大鼠48 只,随机选取10 只大鼠作为正常对照组,其余38 只大鼠饲喂高脂饲料联合注射30 mg/kg mb链脲佐菌素建立2型糖尿病(type 2 diabetes mellitus,T2DM)模型。以大鼠随机血糖浓度不低于16.7 mmol/L作为造模成功判断标准,按血糖浓度分层将大鼠随机分为T2DM模型组、低剂量槲皮素(L-QU)、高剂量槲皮素(H-QU)干预组,每组10 只,连续灌胃12 周。测定大鼠胰腺组织匀浆液的氧化损伤和抗氧化指标,运用Western Blot、实时定量聚合酶链式反应测定Nrf2、血红素氧合酶1(heme oxygenase 1,HO-1)、谷胱甘肽硫转移酶(glutathione S-transferase,GST)、NADP(H):醌氧化还原酶1(NADP(H):quinone oxido-reductase 1,NQO1)蛋白及其mRNA表达量。结果:与T2DM模型组相比,低、高剂量槲皮素干预显著降低了大鼠血糖浓度和胰腺丙二醛含量(P<0.05),减轻胰岛素抵抗,显著提高超氧化物歧化酶等抗氧化酶活力(P<0.05),Nrf2以及下游抗氧化酶HO-1、NQO1的蛋白含量和mRNA表达量均显著上升(P<0.05)。结论:槲皮素可能是通过激活胰腺组织Nrf2信号通路,上调下游抗氧化酶表达,进而减轻T2DM大鼠胰腺氧化损伤,改善胰岛素抵抗,调节血糖水平,从而发挥防治糖尿病的作用。  相似文献   
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冯晨  于洋 《食品工业科技》2021,42(3):304-309,319
为探究枸杞多糖(Lycium barbarum polysaccharide,LBP)对脂多糖(lipopolysaccharide,LPS)诱导的BV2小胶质细胞的保护作用。本研究利用MTT法检测细胞活性,ELISA检测炎症因子的分泌,Western Blot检测蛋白表达情况。结果显示,单独LPS处理BV2小胶质细胞后,细胞的活性无显著变化而细胞上清液中的炎症因子PGE2、IL-1β、IL-6及TNF-α释放显著增多;将枸杞多糖梯度与LPS诱导的BV2小胶质细胞共孵育24 h后,有效地提升了LPS诱导的BV2小胶质细胞的活性,同时显著抑制了LPS激活的BV2小胶质细胞炎症因子的释放(P<0.05);流式结果表明,LPS组小胶质细胞可产生大量ROS,小胶质细胞经不同浓度LBP处理12 h后,ROS含量显著降低(P<0.05);Western Blot检测结果显示,与对照组相比,LPS组和LBP组中NF-κB信号通路相关蛋白表达及细胞核内p65蛋白表达水平均显著上调(P<0.05),且与LBP浓度成反比,而细胞质内p65蛋白表达显著降低(P<0.05),且随着LBP浓度增加而降低。本研究表明,枸杞多糖对LPS激活的BV2小胶质细胞有显著的保护作用,对于LPS激活的BV2小胶质细胞引起的炎症反应具有抑制作用,同时能抑制小胶质细胞中ROS的含量以发挥抗氧化应激作用,同时有效地抑制LPS刺激后细胞内p-TAK1、iκB、p-iκB及p-p65的表达。  相似文献   
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