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101.
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从森林脑炎病毒感染的鼠脑组织中直接抽提总核酸,然后经Sepharose4B柱层析将病毒RNA与细胞RNA分离,方法简便、分离的病毒RNA在260nm处有典型的紫外吸收光谱,260/280nm的比值近似2,对RNase敏感,有感染性。 相似文献
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目的:构建小鼠NOMO1基因RNA干扰载体,比较其对P19细胞NOMO1基因的抑制效率,以研究NOMO1基因与P19细胞向心肌细胞方向分化的关系?方法:利用Designer3.0软件设计小鼠NOMO1基因干扰片段,合成shRNA序列,再行寡核苷酸双链的合成,退火后形成的寡核苷酸双链克隆到pGPU6/Hygro载体的黏性末端,连接产物转化到感受态细胞,增菌,质粒扩增,质粒DNA抽提,使用PstⅠ?BamHⅠ进行双酶切和DNA测序鉴定重组克隆?将小鼠NOMO1基因RNA干扰载体转染P19细胞,以RT-PCR技术验证NOMO1基因在P19细胞中的mRNA表达?以DMSO诱导分化方案诱导P19细胞向心肌细胞分化,采用定量 RT-PCR技术检测P19细胞中α-MHC等基因mRNA的表达,评估NOMO1与P19干细胞向心肌细胞方向分化的关系?结果:双酶切证实shRNA正确插入质粒,测序结果表明插入的序列正确?载体转染的P19细胞筛选稳定表达株,经RT-PCR和Western blot验证4个位点设计的干扰质粒对NOMO1在P19细胞中的mRNA表达均具有较高的抑制效率?转染后P19细胞的α-MHC基因mRNA表达则显著下调(P < 0.05)?结论:成功构建小鼠NOMO1基因RNA干扰载体,为研究NOMO1基因与P19细胞向心肌细胞方向分化的关系提供了稳定的转染细胞工具,NOMO1可能通过诱导α-MHC等基因表达,促进P19干细胞向中胚层的分化? 相似文献
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107.
Xiaomin Hu Dan Wu Bing Zou Huiling Xiao Tao Yang Chenxi Wang Hui Zhou Wen Shen Chenjie Zhang Tao Wu 《Journal of thoracic disease》2022,14(4):1172
BackgroundIt is considered that circRNA can participate in regulating the occurrence and effects of ventricular arrhythmia (VA) through competing endogenous RNA (ceRNA) mechanism, regulating pre-mRNA and regulating parental gene expression. Therefore, we used animal modeling and high-throughput differential screening to screen out circRNA related to VA and study its possible mechanism of action on VA.MethodsThe rat model of myocardial ischemia VA was established. High-throughput screening of the differentiated circRNA was conducted and verified by real-time quantitative polymerase chain reaction (qRT-PCR) and Western blot. Lv-circRNA01724 lentivirus was constructed using molecular biology. Primary isolation of the rat cardiomyocytes, hypoxia modeling, Lv-circRNA01724 transfection, mode of action verification, and dual luciferase detection of circRNA01724 and miR-323-5p was performed.ResultsThrough qRT-PCR verification of circRNA01724, circRNA02230, circRNA02088, miR-323-5p, miR-330-5p, and miR-324-3p expressions, circRNA01724 was selected as the research object. Detection by Western blot showed significantly lower Cx43, ZO-1, and α-catenin expressions in rat myocardial tissue in the model group compared with the control group at 1, 7, 14, and 28 days old. On identification of the isolated primary rat cardiomyocytes by immunofluorescence, the α-SMA characteristic protein expression indicated that the isolation was successful. Verification of rat cardiomyocytes transfected with Lv-circRNA01724 suggested overexpression in cells. The miR-323-5p was also highly expressed in the rat cardiomyocyte hypoxia model following Lv-circRNA01724 transfection. Detection by flow cytometry showed that modeling of the transfected Lv-circRNA01724 had a significant increased apoptotic rate. Detection by Western blot showed that modeling of the transfected Lv-circRNA01724 cells had significantly decreased Cx43, ZO-1, and α-catenin compared with the model group.ConclusionsHigh-throughput screening of circRNA01724 can promote the apoptosis of hypoxic cardiomyocytes, which is related to the rat model of myocardial ischemia VA and may be a potential target for the treatment of VA. 相似文献
108.
目的观察靶向封闭CapG基因对胰腺癌细胞株BxPC3运动侵袭能力的影响。方法设计并体外合成靶向CapG的小干扰RNA,将其转染到BxPC3细胞中,蛋白质印迹法检测转染前后细胞中CapG蛋白的表达,采用Transwell小室检测转染前后细胞运动侵袭能力的改变。结果CapGsiRNA能有效降低BxPC3细胞中CapG的表达,CapG在蛋白质水平的表达抑制率达80%左右。抑制BxPC3细胞中CapG的表达后,BxPC3细胞的运动侵袭能力明显下降,穿过人工基底膜的细胞数显著低于阴性对照组和空白对照组(P〈0.05)。结论封闭CapG表达能明显抑制胰腺癌细胞BxPC3在体外的运动侵袭能力。 相似文献
109.
目的:检测lncRNA DNM3OS在喉鳞状细胞癌(laryngeal squamous cell carcinoma,LSCC)组织和LSCC细胞株中的表达及其临床意义,探讨其对LSCC TU177细胞体外增殖、迁移及侵袭的影响,并分析DNM3OS与EMT的关系.方法:从河北医科大学第四医院生物标本库选取2014年3... 相似文献
110.
Andrea Haller Roger B. Altman Marie F. Soulière Scott C. Blanchard Ronald Micura 《Proceedings of the National Academy of Sciences of the United States of America》2013,110(11):4188-4193
Thiamine pyrophosphate (TPP)-sensitive mRNA domains are the most prevalent riboswitches known. Despite intensive investigation, the complex ligand recognition and concomitant folding processes in the TPP riboswitch that culminate in the regulation of gene expression remain elusive. Here, we used single-molecule fluorescence resonance energy transfer imaging to probe the folding landscape of the TPP aptamer domain in the absence and presence of magnesium and TPP. To do so, distinct labeling patterns were used to sense the dynamics of the switch helix (P1) and the two sensor arms (P2/P3 and P4/P5) of the aptamer domain. The latter structural elements make interdomain tertiary contacts (L5/P3) that span a region immediately adjacent to the ligand-binding site. In each instance, conformational dynamics of the TPP riboswitch were influenced by ligand binding. The P1 switch helix, formed by the 5′ and 3′ ends of the aptamer domain, adopts a predominantly folded structure in the presence of Mg2+ alone. However, even at saturating concentrations of Mg2+ and TPP, the P1 helix, as well as distal regions surrounding the TPP-binding site, exhibit an unexpected degree of residual dynamics and disperse kinetic behaviors. Such plasticity results in a persistent exchange of the P3/P5 forearms between open and closed configurations that is likely to facilitate entry and exit of the TPP ligand. Correspondingly, we posit that such features of the TPP aptamer domain contribute directly to the mechanism of riboswitch-mediated translational regulation. 相似文献