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61.
Head and neck squamous cell carcinoma (HNSCC) is the fifth most common cancer in men with an incidence of about 780000 new cases per year worldwide and a poor rate of survival. There is a need for a better understanding of HNSCC, for the development of rational targeted interventions and to define new prognostic or diagnostic markers. To address these needs, we performed a large-scale differential display comparison of hypopharyngeal HNSCCs against histologically normal tissue from the same patients. We have identified 70 genes that exhibit a striking difference in expression between tumours and normal tissues. There is only a limited overlap with other HNSCC gene expression studies that have used other techniques and more heterogeneous tumour samples. Our results provide new insights into the understanding of HNSCC. At the genome level, a series of differentially expressed genes cluster at 12p12-13 and 1q21, two hotspots of genome disruption. The known genes share functional relationships in keratinocyte differentiation, angiogenesis, immunology, detoxification, and cell surface receptors. Of particular interest are the 13 'unknown' genes that exist only in EST, theoretical cDNA and protein databases, or as chromosomal locations. The differentially expressed genes that we have identified are potential new markers and therapeutic targets.  相似文献   
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Cost-efficiency targets, used to encourage downward pressure on hospital unit costs, have been employed within the UK NHS for many years. There has been considerable speculation that these targets create incentives to reduce beds and increase occupancy rates at the expense of holding spare capacity to accommodate fluctuations in emergency admissions. This research used panel data for the period 1994/1995-1999/2000, supplemented by a series of semi-structured interviews, to explore the strategies Trusts employ to reduce unit costs. No relationship could be found between published targets and changes in unit costs, nor that targets were successful in reducing the dispersion of unit costs over time. Interviews revealed that efficiency gains required of Trusts, usually dictated by the local health economy, often bore no correspondence to the national or regional published targets. Results further indicated that contrary to prior speculation, Trusts divide into two distinct groups, those with high occupancy rates and those with a high proportion of free beds to accommodate emergencies, with Trust characteristics displaying stability over time. A pressing need for future work is the development of measures to encourage efficiency that take account of quality improvement.  相似文献   
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Introduction: Enhancement of glucose metabolism and repression of oxidative phosphorylation followed by the Warburg effect is the common hallmark of cancer cells. Hexokinase II (HKII) plays a dual role – first, HKII up-regulation results in increased glycolysis rates. Second, association of VDAC and HKII contributes to inhibition of apoptosis through repression of the formation of mitochondrial permeability transition pores.

Areas covered: In this review, the role of HKII in evasion of apoptosis, aspects of HKII expression regulation, novel approaches targeting HKII and VDAC–HKII complexes and their application areas are discussed.

Expert opinion: The dual role of HKII in cancer cells makes it an attractive target for anti-cancer therapy. Several agents, either synthetic or plant-derived, that target hexokinase and induce VDAC–HK complex dissociation have been identified to date. Targeting hexokinase, HK–VDAC complexes as well as other glycolytic proteins not only improves the efficacy of commonly used drugs. The most prominent benefit of this approach is the ability to overcome drug resistance, for example, to cisplatin or sorafenib. In some cases, it could create an insurmountable challenge for selection of appropriate therapy. Future studies and trials should address the issue of how to transfer these approaches into clinical practice.  相似文献   
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As the pharmaceutical industry continues to re-strategise and focus on low-risk, relatively short-term gains for the sake of survival, we need to re-invigorate the early stages of drug discovery and rebalance efforts towards novel modes of action therapeutics and neglected genetic and tropical diseases. Academic drug discovery is one model which offers the promise of new approaches and an alternative organisational culture for drug discovery as it attempts to apply academic innovation and thought processes to the challenge of discovering drugs in addressing real unmet need.  相似文献   
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The disappointing results in long-term survival of patients who have a resectable non-small cell lung cancer (NSCLC) may reflect the lack of knowledge on the way by which molecular abnormalities in neoplastic cells affect responsiveness to adjuvant therapy. This issue deserves intensive investigation to select methodological approaches for a new generation of chemotherapeutic strategies. Remarkable advances in the understanding of NSCLC biology have been made, including the discovery of critical mutations in oncogenes (i.e. K-Ras and c-myc), as well as the loss of tumor-suppressor genes, such as TP53, p16INK4 or Rb. Other studies demonstrated the role of mutations or deregulation of the expression of several molecular determinants involved in cell cycle control such as epidermal growth factor receptor (EGFR). All these characteristics, as well as alterations in gene products directly related to drug activity, might contribute to the aggressive behaviour of NSCLC. The future challenge of chemotherapy of NSCLC relies on the identification of molecular markers that are predictive of drug sensitivity and are helpful in the selection of chemotherapeutic agents best suited to the individual patient. Other intriguing issues will be the identification of the optimal drug sequence in combination regimens and the pharmacogenetics of severe toxicities. Moreover, due to the developments of novel technologies to decipher genetic alterations involved in tumor progression, new agents are gaining momentum, including inhibitors of intracellular signal transduction, and a large body of research, using prospective clinical trials, should be devoted to this area.  相似文献   
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目的:基于网络药理学分析土鳖虫对破血逐瘀相关疾病的作用机制。方法:经文献查阅并结合PubChem、SwissADME、SwissTargetPrediction和TCMSP等数据库对土鳖虫已知成分及其对应靶点进行搜集,并与经GeneCards、OMIM、TTD、HPO数据库搜索得到的“破血逐瘀”相关靶点进行交互分析得到共同靶点;通过蛋白-蛋白质-蛋白质相互作用(PPI)分析、基因本体(GO)分析和京都基因与基因组百科全书(KEGG)分析,构建土鳖虫“成分-靶点-疾病”网络,探讨土鳖虫破血逐瘀功效的作用机制。同时采用体外纤溶实验评价土鳖虫水溶性蛋白质与其他成分的活性差异。结果:筛选得到土鳖虫活性化合物54个,共对应靶点653个;与血瘀相关的17种疾病的16141个作用靶点经交互分析得出两者共有靶点26个。GO和KEGG分析结果表明,土鳖虫已知成分主要涉及嘌呤代谢通路、细胞能量代谢通路、环磷酸鸟苷(cGMP)信号通路、Toll样受体信号通路、醛固酮合成代谢通路、三酰甘油合成通路等13条信号通路,通过干预DNA转录、细胞能量代谢等生物功能发挥药效。同时体外纤溶实验得出土鳖虫水溶性蛋白质较其他成分表现出更强的纤溶活性。结论:土鳖虫已知活性成分并不能很好的证明其对破血逐瘀相关疾病的治疗有显著的效果。结合土鳖虫水溶性蛋白质促纤溶作用,为下一步土鳖虫纤溶物质基础的研究提供参考。  相似文献   
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中药药理分子基础的探索与延缓衰老密码的解读   总被引:1,自引:0,他引:1  
黄酮类与雌性激素立体结构的相似,胆汁酸与齐墩果酸等五环三萜药物成分的结构相似,为它们通过雌性激素受体ER和GPR30,与胆汁酸受体FXR和TGR5引起药理学效果提供了解释;中药有效成分对NFκB的阻止,为抗炎药物在非传统炎症概念上的相关疾病治疗得到了诠释。基于这些研究,从中药有效成分与受体配体结构相似性,以及植物小分子在细胞内信号传导调节中的作用阐述中药的功用;并从分子水平剖析中药"七情"理论的多靶点性,以及解读延缓衰老的因子与中药抗衰老的研究前景。  相似文献   
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