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81.
Hepatocellular carcinoma (HCC) is one of the most prevalent malignancies worldwide. HCC is associated with several etiological factors, including HBV/HCV infections, cirrhosis, and fatty liver diseases. However, the molecular mechanism underlying HCC development remains largely elusive. The advent of high-throughput sequencing has unveiled an unprecedented discovery of a plethora of long noncoding RNAs (lncRNAs). Despite the lack of coding capacity, lncRNAs have key roles in gene regulation through interacting with various biomolecules. It is increasingly evident that the dysregulation of lncRNAs is inextricably linked to HCC cancer phenotypes, suggesting that lncRNAs are potential prognostic markers and therapeutic targets. In light of the emerging research in the study of the regulatory roles of lncRNAs in HCC, we discuss the association of lncRNAs with HCC. We link the biological processes influenced by lncRNAs to cancer hallmarks in HCC and describe the associated functional mechanisms. This review sheds light on future research directions, including the potential therapeutic applications of lncRNAs.  相似文献   
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Senescence marker protein 30 (SMP30) is a cell survival factor playing an important role in vitamin C synthesis and antiapoptosis. Moreover, its cytoprotective role suggests a possibility to be related to cancer cell survival. Mammary carcinoma is a common cancer in both humans and animals. Because of its histopathological diversity, especially in the early stage, histopathological diagnosis may be complicated; therefore, a diagnostic marker is helpful for confirmation. The present study analyzed the expression pattern of SMP30 in mammary carcinoma in humans, dogs, and cats. Immunohistochemistry, immunofluorescence, and western blot analysis were used to investigate SMP30 expression patterns. The expression was specifically observed in neoplastic glandular epithelial cells. The expression increased with the malignancy of glandular epithelial cells with a highly proliferative status. However, SMP30 expression was low in normal mammary gland tissues or well-differentiated adenoma tissues. The patterns were consistently reproduced in canine primary mammary carcinoma cells and MCF-7 and MDA-MB-231 human carcinoma cell lines. This study provides useful information to understand SMP30 expression in various stages of mammary carcinoma and to suggest its utility as a pan-species diagnostic marker, thereby helping to establish strategies for diagnosing mammary carcinoma in several species.  相似文献   
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目的:探讨核糖核苷酸还原酶M2(RRM2)在肝癌细胞对5-氟尿嘧啶(5-FU)耐药中的作用,并开发潜在的策略来提高肝癌细胞对5-FU的敏感性。方法:利用Western blot检测5-FU耐药肝癌细胞(BEL/5-FU)与非耐药肝癌细胞(BEL7402)中RRM2蛋白的表达差异;通过用RNA干扰技术下调BEL/5-FU细胞中RRM2的表达或RRM2抑制剂3-AP(Triapine)抑制RRM2活性;CCK-8和集落形成实验用于检测细胞的增殖能力;使用高内涵细胞成像系统仪检测与分析细胞凋亡。结果:BEL/5-FU细胞中RRM2的表达量是BEL7402细胞的2.5倍。RNA干扰技术能够下调BEL/5-FU细胞中RRM2的表达,并使5-FU对BEL/5-FU细胞的半数抑制浓度(IC50)下降约50%,同时细胞集落形成能力也显著减弱。3-AP与5-FU联合处理BEL/5-FU细胞,使5-FU对BEL/5-FU细胞的IC50下降约40%,细胞集落形成能力减弱,并促进5-FU导致的细胞凋亡。结论:RRM2与肝癌细胞对5-FU的耐药相关,本研究通过抑制RRM2的活性来逆转肝癌细胞对5-FU的耐药,为提高肝癌的5-FU化疗疗效提供新靶点和新思路。  相似文献   
86.
田亚丽  奉林  赵万  谷敏  沈涵菁  柴晓艳 《金属学报》2021,26(10):1118-1126
目的:研究乳腺癌易感基因1(breast cancer susceptibility gene1,BRCA1)单核苷酸多态性(single nucleotide polymorphism,SNP)对转移性食管鳞癌患者化疗敏感性及生存预后的影响。方法:选取2016年6月至2020年2月于苏州科技城医院收治的153例初治转移性食管鳞癌患者,均给予顺铂联合卡培他滨化疗。首次化疗前抽静脉血5ml提取DNA,应用TaqMan探针法检测BRCA1基因rs8176318G/T 、rs799917T/C和rs1799966T/C多态性位点的基因型,探讨不同基因型之间化疗客观反应率 (objective response rate,RR)和总生存期(overall survival,OS)的差异。结果:rs799917T/C多态性与转移性食管鳞癌化疗敏感性密切相关,TT、TC、CC基因型化疗有效率呈逐渐升高趋势(TT 22.5%、TC 38.6%、CC 55.3%,χ2=8.041,P=0.018)。CC基因型化疗反应率为TT基因型的4.154倍 (95%CI:1.549~11.141,χ2=8.007,P=0.005);TC+CC基因型化疗反应率为TT基因型的2.678倍 (95%CI:1.160~6.179,χ2=5.329,P=0.021)。Kaplan-Meier分析显示rs1799966T/C多态性与患者生存时间相关, TT、TC和CC基因型携带者中位OS呈逐渐延长趋势 (TT8.5月、TC12.1月、CC13.8月,χ2=11.864,P=0.003); TC+CC基因型患者中位OS为12.6个月,与TT组相比明显延长(χ2=10.515,P=0.001)。COX回归模型分析结果显示,rs1799966T/C多态性仍是影响患者OS的独立预后因素。未发现rs8176318G/T多态性与化疗反应及预后之间存在统计学关联。结论:BRCA1基因rs799917多态性与转移性食管鳞癌顺铂联合卡培他滨化疗敏感性相关,rs1799966多态性可能影响患者的生存预后。  相似文献   
87.
目的探讨表皮生长因子(EGF)G61A位点(EGF +61)多态性与慢性乙型肝炎肝细胞癌的相关性。方法运用多聚酶链式反应-限制性片段长度多态性(PCR-RFLP)技术,检测中国人群中215例慢性乙型肝炎肝细胞癌患者和104例正常对照者EGF+61位点的基因型,分析基因型及等位基因的分布频率。结果EGF +61位点基因型及等位基因在乙型肝炎肝细胞癌患者及对照者的分布频率差异均无统计学意义。TNMⅠ、Ⅱ及TNMⅢ、Ⅳ两组的基因型及等位基因的分布频率差异也无统计学意义。结论在中国人群中,EGF +61位点的基因多态性与乙型肝炎肝细胞癌的发生和进展程度无密切关系。  相似文献   
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Hepatocellular carcinoma (HCC) develops almost entirely in the presence of chronic inflammation. Chronic hepatitis B virus (HBV) infection with recurrent immune-mediated liver damage ultimately leads to cirrhosis and HCC. It is widely accepted that HBV infection induces the dysfunction of the innate and adaptive immune responses that engage various immune cells. Natural killer (NK) cells are associated with early antiviral and antitumor properties. On the other hand, inflammatory cells release various cytokines and chemokines that may promote HCC tumorigenesis. Moreover, immunosuppressive cells such as regulatory T cells (Treg) and myeloid-derived suppressive cells play a critical role in hepatocarcinogenesis. HBV-specific CD8+ T cells have been identified as pivotal players in antiviral responses, whilst extremely activated CD8+ T cells induce enormous inflammatory responses, and chronic inflammation can facilitate hepatocarcinogenesis. Controlling and maintaining the balance in the immune system is an important aspect in the management of HBV-related HCC. We conducted a review of the current knowledge on the immunopathogenesis of HBV-induced inflammation and the role of such immune activation in the tumorigenesis of HCC based on the recent studies on innate and adaptive immune cell dysfunction in HBV-related HCC.  相似文献   
90.
Corosolic acid (CA; 2α-hydroxyursolic acid) is a natural pentacyclic triterpenoid with antioxidant, antitumour and antimetastatic activities against various tumour cells during tumourigenesis. However, CA’s antitumour effect and functional roles on human oral squamous cell carcinoma (OSCC) cells are utterly unknown. In this study, our results demonstrated that CA significantly exerted an inhibitory effect on matrix metalloproteinase (MMP)1 expression, cell migration and invasion without influencing cell growth or the cell cycle of human OSCC cells. The critical role of MMP1 was confirmed using the GEPIA database and showed that patients have a high expression of MMP1 and have a shorter overall survival rate, confirmed on the Kaplan–Meier curve assay. In the synergistic inhibitory analysis, CA and siMMP1 co-treatment showed a synergically inhibitory influence on MMP1 expression and invasion of human OSCC cells. The ERK1/2 pathway plays an essential role in mediating tumour progression. We found that CA significantly inhibits the phosphorylation of ERK1/2 dose-dependently. The ERK1/2 pathway played an essential role in the CA-mediated downregulation of MMP1 expression and in invasive motility in human OSCC cells. These findings first demonstrated the inhibitory effects of CA on OSCC cells’ progression through inhibition of the ERK1/2–MMP1 axis. Therefore, CA might represent a novel strategy for treating OSCC.  相似文献   
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