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91.
【摘要】 目的 探讨基质金属蛋白酶抑制剂(RECK)、基质金属蛋白酶 9(MMP 9)在三阴性乳腺癌(TNBC)组织、癌旁组织中的表达及与TNBC临床病理的关系。方法 选择绵阳市中心医院乳腺外科2011年5月~2013年7月经病理证实为TNBC的72例石蜡标本及同 患者癌旁组织,利用免疫组化组织芯片技术检测其RECK、MMP 9蛋白的表达。结果 RECK在TNBC组织及癌旁组织中阳性表达率分别为4306%、8056%(P=0000)。TNBC中RECK的表达与临床分期(P=0009)、组织学分级(P=0010)、腋窝淋巴结转移情况(P=0000)相关。MMP 9在TNBC组织及癌旁组织中阳性表达率分别为625%、1528%(P=0000)。TNBC中MMP 9的表达与肿瘤大小(P=0017)、临床分期(P=0001)、组织学分级(P=0001)、腋窝淋巴结转移状况(P=0001)、Ki 67表达情况(P=0034)相关。TNBC中RECK与MMP 9表达呈负相关(r= 0195,P<005)。结论 RECK的表达缺失与MMP 9过度表达与TNBC浸润、转移有关,有望成为TNBC的预后指标,并且有可能成为TNBC治疗的靶点。  相似文献   
92.
Data generated using high-throughput DNA microarrays are changing the way we think about systemic lupus erythematosus (SLE). The identification of an interferon gene-expression signature in the majority of patients with SLE, especially those with severe SLE, has stimulated substantial interest in targeting the interferon pathway for the treatment SLE and has catalyzed new inquiries into the utility of interferon signaling as a diagnostic and prognostic biomarker for SLE. As these genomic datasets enlarge and mature, new signatures are being identified that implicate other pathways dysregulated in SLE, including oxidative phosphorylation, immunoglobulin production and granulocyte maturation. Highly anticipated longitudinal studies will be important in defining how this information will ultimately change the way SLE is managed in the clinical setting.  相似文献   
93.
背景 胎儿鼻骨发育情况评估作为常规产前超声检查项目,是胎儿染色体检查的重要指标,近几年染色体微阵列分析技术(CMA)的应用使得产前胎儿染色体疾病的检查范围更广、准确度更高,在此基础上有必要对鼻骨发育异常和染色体异常之间的相关性重新进行总结,为临床提供参考。目的 探讨胎儿鼻骨发育异常或与其他产前筛查高危因素结合在预测胎儿染色体异常中的价值,以及CMA在胎儿鼻骨发育异常遗传学检测中的应用价值。方法 选取2016年12月-2020年1月于内蒙古自治区妇幼保健院进行产前超声检查并提示胎儿鼻骨缺失或发育不良的92例孕妇及胎儿为研究对象。收集其产检信息、遗传学检测结果及妊娠结局。遗传学检测方法包括染色体核型分析和CMA。结果 染色体核型分析检出染色体异常19例(20.7%),均为21-三体;CMA检出染色体异常25例(27.2%),包括21-三体19例,染色体微缺失微重复6例。孤立性与非孤立性鼻骨发育异常胎儿染色体异常发生率比较,差异无统计学意义(P>0.05)。与单纯孤立性鼻骨发育异常胎儿相比,孤立性鼻骨发育异常+颈项透明层(NT)增厚、孤立性鼻骨发育异常+血清学筛查(MSS)高风险、孤立性鼻骨发育异常+无创产前筛查(NIPT)高风险、孤立性鼻骨发育异常+2种及以上产前筛查高危因素胎儿染色体异常发生率均升高(P<0.05)。结论 鼻骨缺失或发育不良的胎儿染色体异常发生率较高,且与基因组变异有关;染色体核型分析、CMA结合其他产前筛查高危因素将有效提高染色体异常的检出率。CMA的应用为产前诊断提供了更多的染色体变异信息,建议所有类型的胎儿鼻骨缺失或发育不良进行染色体核型分析与CMA结合的遗传学检测。  相似文献   
94.
《Vaccine》2017,35(52):7273-7282
In this study, we evaluated the immunogenicity, protective efficacy and peptide-based immune signatures of antibodies raised in mice after sublingual immunization with a recombinant form of the P1 (aka AgI/II, PAc) adhesin (P139-512) of Streptococcus mutans, a major etiological agent of dental caries. Sublingual administration of P139-512 in combination with the mucosal adjuvant LTK4R (a derivative of heat-labile LT toxin) induced strong and long-lasting systemic and mucosal immune responses. Incorporation of the adjuvant resulted in an enhancement of the anti-adhesive and anti-colonization activity against S. mutans as evaluated both under in vitro and in vivo conditions. Incorporation of the adjuvant to the vaccine formulation also changed the epitope specificity of the induced antibodies as determined by immunological signatures of sera collected from vaccinated mice. Use of a peptide microarray library led to the identification of peptide targets recognized by antibodies in serum samples with enhanced anti-adhesive effects. Altogether, the results presented herein showed that the sublingual administration of a P1-based subunit vaccine represents a promising approach for the prevention of dental caries caused by S. mutans. In addition, the present study disclosed the role of adjuvants on the epitope specificity and functionality of antibodies raised by subunit vaccines.  相似文献   
95.
96.
Tissue microarrays (TMAs) represent a powerful method for undertaking large‐scale tissue‐based biomarker studies. While TMAs offer several advantages, there are a number of issues specific to their use which need to be considered when employing this method. Given the investment in TMA‐based research, guidance on design and execution of experiments will be of benefit and should help researchers new to TMA‐based studies to avoid known pitfalls. Furthermore, a consensus on quality standards for TMA‐based experiments should improve the robustness and reproducibility of studies, thereby increasing the likelihood of identifying clinically useful biomarkers. In order to address these issues, the National Cancer Research Institute Biomarker and Imaging Clinical Studies Group organized a 1‐day TMA workshop held in Nottingham in May 2012. The document herein summarizes the conclusions from the workshop. It includes guidance and considerations on all aspects of TMA‐based research, including the pre‐analytical stages of experimental design, the analytical stages of data acquisition, and the postanalytical stages of data analysis. A checklist is presented which can be used both for planning a TMA experiment and interpreting the results of such an experiment. For studies of cancer biomarkers, this checklist could be used as a supplement to the REMARK guidelines.  相似文献   
97.
Human cell lines are an important resource for research, and are often used as in vitro models of human diseases. In response to the mandate that all cells should be authenticated, we discovered that the MDA-MB-231 cells that were in use in our lab, did not validate based on the alleles of 9 different markers (STR Profile). We had been using this line as a model of triple negative breast cancer (TNBC) that has the ability to form tumors in immuno-compromised mice. Based on marker analysis, these cells most closely resembled the MCF10A line, which are a near diploid and normal mammary epithelial line. Yet, the original cells express carbonic anhydrase IX (CAIX) both constitutively and in response to hypoxia and are features that likely drive the aggressive nature of these cells. Thus, we sought to sub-purify CAIX-expressing cells using Fluorescence Activated Cell Sorting (FACS). These studies have revealed a new line of cells that we have name UFH-001, which have the TNBC phenotype, are positive for CAIX expression, both constitutively and in response to hypoxia, and behave aggressively in vivo. These cells may be useful for exploring mechanisms that underlie progression, migration, and metastasis of this phenotype. In addition, constitutive expression of CAIX allows its evaluation as a therapeutic target, both in vivo and in vitro.  相似文献   
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99.
目的建立一种基于随机聚合酶链反应的病原细菌基因芯片筛查检测技术。方法用生物学软件分析7种病原菌特异性基因序列的保守性区域,利用Oligo 6.0软件设计针对靶细菌的一系列探针,制备检测用基因芯片。细菌基因组DNA在随机引物扩增中掺入氨基丙烯-dUTP,产物偶联荧光染料后与芯片上探针杂交,通过芯片扫描仪和图像分析软件对结果进行判断。选取19种病原菌基因组DNA进行芯片特异性验证和灵敏度评价,使用问号钩端螺旋体对应靶探针进行基因芯片检测方法重复性验证,并制备问号钩端螺旋体模拟水污染样本进行芯片检测。结果在均一的杂交条件下4种靶细菌均能得到相应特异性杂交图谱,其他非目的细菌均为阴性结果,3种靶细菌基因组DNA最低检测浓度为14.43~363.4 pg/μl,芯片重复性变异系数CV值〈15%,最低可检测含问号钩端螺旋体7×105条/ml模拟水污染样本。结论初步建立的随机聚合酶链反应结合芯片技术的检测方法可用于多种病原菌筛查检测,为细菌高通量筛查与鉴定技术提供了新的思路和实验依据。  相似文献   
100.
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