首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   9657篇
  免费   849篇
  国内免费   155篇
耳鼻咽喉   50篇
儿科学   252篇
妇产科学   80篇
基础医学   1687篇
口腔科学   100篇
临床医学   795篇
内科学   1130篇
皮肤病学   44篇
神经病学   1138篇
特种医学   104篇
外科学   381篇
综合类   499篇
预防医学   914篇
眼科学   106篇
药学   2698篇
  6篇
中国医学   312篇
肿瘤学   365篇
  2023年   154篇
  2022年   196篇
  2021年   307篇
  2020年   380篇
  2019年   372篇
  2018年   342篇
  2017年   339篇
  2016年   361篇
  2015年   362篇
  2014年   548篇
  2013年   855篇
  2012年   516篇
  2011年   531篇
  2010年   441篇
  2009年   490篇
  2008年   466篇
  2007年   396篇
  2006年   328篇
  2005年   297篇
  2004年   254篇
  2003年   232篇
  2002年   176篇
  2001年   146篇
  2000年   151篇
  1999年   157篇
  1998年   102篇
  1997年   95篇
  1996年   108篇
  1995年   100篇
  1994年   96篇
  1993年   114篇
  1992年   102篇
  1991年   101篇
  1990年   105篇
  1989年   83篇
  1988年   83篇
  1987年   80篇
  1986年   78篇
  1985年   91篇
  1984年   84篇
  1983年   47篇
  1982年   68篇
  1981年   60篇
  1980年   52篇
  1979年   42篇
  1978年   33篇
  1977年   31篇
  1976年   42篇
  1975年   23篇
  1974年   14篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
《Drug discovery today》2022,27(1):82-101
WNT/β-catenin signaling orchestrates various physiological processes, including embryonic development, growth, tissue homeostasis, and regeneration. Abnormal WNT/β-catenin signaling is associated with various cancers and its inhibition has shown effective antitumor responses. In this review, we discuss the pathway, potential targets for the development of WNT/β-catenin inhibitors, available inhibitors, and their specific molecular interactions with the target proteins. We also discuss inhibitors that are in clinical trials and describe potential new avenues for therapeutically targeting the WNT/β-catenin pathway. Furthermore, we introduce emerging strategies, including artificial intelligence (AI)-assisted tools and technology-based actionable approaches, to translate WNT/β-catenin inhibitors to the clinic for cancer therapy.  相似文献   
2.
Mixed lineage leukemia 1(MLL1)是组蛋白甲基转移酶SET家族的成员之一。MLL1与WDR5、RbBP5、Ash2L和DPY-30组成MLL1甲基转移酶复合物调控组蛋白H3的第4位赖氨酸的甲基化水平,对造血系统的发育和血细胞的更新至关重要。部分白血病患者体内存在因MLL1基因易位而产生的致癌蛋白——MLL1融合蛋白,MLL1融合蛋白在发挥其致癌作用时需要功能完整的MLL1酶复合物,故靶向MLL1-WDR5的蛋白-蛋白相互作用成为治疗MLL1融合型白血病的潜在策略。本文对MLL1-WDR5蛋白-蛋白相互作用的生物学机制、结构信息以及抑制剂进行了系统的总结,并结合已报道数据对该领域进行了展望,以期为后续研究提供参考。  相似文献   
3.
赵文  赵斐  李敏  叶慧芳 《眼科新进展》2022,(12):962-966
目的 探讨补体因子H(CFH)基因多态性与玻璃体液血管内皮生长因子(VEGF)对年龄相关性黄斑变性(AMD)患者抗VEGF疗效影响的交互作用。方法 选取2020年5月~2022年1月广州医科大学附属第三医院眼科149例(149眼)AMD患者为研究对象,根据抗VEGF治疗是否有应答,分为应答组(111例)、无应答组(38例)。比较两组患者CFH基因多态性、玻璃体液VEGF表达水平,比较CFH位点rs1061170不同基因型患者玻璃体液VEGF表达水平,采用Logistic分析抗VEGF疗效的相关影响因素,采用交互作用系数γ分析CFH基因多态性、玻璃体液VEGF的交互作用是否存在及其作用类型。结果 无应答组患者CFH位点rs1061170基因型分布与应答组比较,差异有统计学意义(P<0.05)。无应答组患者玻璃体液VEGF高于应答组(P<0.05)。在全部AMD患者中,玻璃体液VEGF高水平患者CFH位点rs1061170基因型分布与低水平患者比较,差异有统计学意义(P<0.05)。在全部AMD患者中,玻璃体液VEGF、CFH位点rs1061170 CC基因型均是抗VEGF疗效的独立相关影响因素(均为P<0.05)。在全部AMD患者中,单独玻璃体液VEGF的OR值为41.250,单独rs1061170基因型CC的OR值为22.000,两者共存时的OR值为759.000,且γ为1.068,提示患者玻璃体液VEGF升高与CFH位点rs1061170 CC基因型在抗VEGF疗效中呈正向交互作用;同时交互作用<两单独因素OR值的乘积,则患者玻璃体液VEGF升高与CFH位点rs1061170 CC基因型交互作用符合次相乘模型。结论 玻璃体液VEGF升高与CFH位点rs1061170 CC基因型在AMD抗VEGF疗效中呈正向交互作用,且交互作用符合次相乘模型,为临床抗VEGF药物精准使用提供参考。  相似文献   
4.
Dabigatran etexilate (DABE), an oral anticoagulant prodrug, is nearly completely metabolized to the dabigatran (DAB) active metabolite by carboxylesterase-1 (CES1) and carboxylesterase-2 (CES2). The high interpatient variation in DAB plasma concentrations, coupled with its low therapeutic index, emphasizes the need to understand how CES1 and CES2 impact active metabolite formation. Previous work focused on CES1 enzyme activity but the contributions of CES2 remain unclear. The purpose of this study was to determine how CES2 activity influences DAB active metabolite formation. We compared the efficiency of DAB formation from DABE when exposed sequentially to human intestinal and then human hepatic microsomes (mimicking the normal metabolic sequence) with the reverse metabolic sequence in which DABE is exposed to hepatic and then intestinal microsomes. The poor efficiency of DAB formation with reverse sequential hydrolysis indicates that CES2 activity is crucial for active metabolite formation. Thus, the decrease in DAB formation with normal sequential hydrolysis was more sensitive to CES2 inhibition by verapamil (CES2 IC50 = 3.4 μM) than CES1 inhibition by diltiazem (CES2 IC50 = 9.1 μM). These results show CES2 activity plays a crucial role in DAB formation and that variability in its activity is an important determinant of therapeutic response.  相似文献   
5.
《Drug discovery today》2022,27(5):1350-1366
The screening of compound–protein interactions (CPIs) is one of the most crucial steps in finding hit and lead compounds. Deep learning (DL) methods for CPI prediction can address intrinsic limitations of traditional HTS and virtual screening with the advantage of low cost and high efficiency. This review provides a comprehensive survey of DL-based CPI prediction. It first summarizes popular databases of small-molecule compounds, proteins and binding complexes. Then, it outlines classical representations of compounds and proteins in turn. After that, this review briefly introduces state-of-the-art DL-based models in terms of design paradigms and investigates their prediction performance. Finally, it indicates current challenges and trends toward better CPI prediction and sketches out crucial approaches toward practical applications.  相似文献   
6.
《Saudi Pharmaceutical Journal》2022,30(11):1572-1588
Non-alcoholic fatty liver disease (NAFLD) is one of the most common complications of a metabolic syndrome caused by excessive accumulation of fat in the liver. Orthosiphon stamineus also known as Orthosiphon aristatus is a medicinal plant with possible potential beneficial effects on various metabolic disorders. This study aims to investigate the in vitro inhibitory effects of O. stamineus on hepatic fat accumulation and to further use the computational systems pharmacology approach to identify the pharmacokinetic properties of the bioactive compounds of O. stamineus and to predict their molecular mechanisms against NAFLD. Methods: The effects of an ethanolic extract of O. stamineus leaves on cytotoxicity, fat accumulation and antioxidant activity were assessed using HepG2 cells. The bioactive compounds of O. stamineus were identified using LC/MS and two bioinformatics databases, namely the Traditional Chinese Medicine Integrated Database (TCMID) and the Bioinformatics Analysis Tool for the Molecular Mechanism of Traditional Chinese Medicine (BATMAN-TCM). Pathway enrichment analysis was performed on the predicted targets of the bioactive compounds to provide a systematic overview of the molecular mechanism of action, while molecular docking was used to validate the predicted targets. Results: A total of 27 bioactive compounds corresponding to 50 potential NAFLD-related targets were identified. O. stamineus exerts its anti-NAFLD effects by modulating a variety of cellular processes, including oxidative stress, mitochondrial β-oxidation, inflammatory signalling pathways, insulin signalling, and fatty acid homeostasis pathways. O. stamineus is significantly targeting many oxidative stress regulators, including JNK, mammalian target of rapamycin (mTOR), NFKB1, PPAR, and AKT1. Molecular docking analysis confirmed the expected high affinity for the potential targets, while the in vitro assay indicates the ability of O. stamineus to inhibit hepatic fat accumulation. Conclusion: Using the computational systems pharmacology approach, the potentially beneficial effect of O. stamineus in NAFLD was indicated through the combination of multiple compounds, multiple targets, and multicellular components.  相似文献   
7.
Rifamycins (rifampin, rifabutin, and rifapentine) play an essential role in the treatment of mycobacterial and some nonmycobacterial infections. They also induce the activity of various drug transporting and metabolizing enzymes, which can impact the concentrations and efficacy of substrates. Many anticoagulant and antiplatelet (AC/AP) agents are substrates of these enzymes and have narrow therapeutic indices, leading to risks of thrombosis or bleeding when coadministered with rifamycins. The objective of this systematic review was to evaluate the effects on AC/AP pharmacokinetics, laboratory markers, and clinical safety and efficacy of combined use with rifamycins. A systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidance was performed. The PubMed, Embase, and Web of Science databases were queried for English-language reports on combination use of rifamycins and AC/AP agents from database inception through August 2021. The 29 studies identified examined warfarin (n = 17), direct oral anticoagulants (DOACs) (n = 8), and antiplatelet agents (n = 4) combined with rifampin (n = 28) or rifabutin (n = 1). Eleven studies were case reports or small case series; 14 reported on pharmacokinetic or laboratory markers in healthy volunteers. Rifampin-warfarin combinations led to reductions in warfarin area under the curve (AUC) of 15%–74%, with variability by warfarin isomer and study. Warfarin dose increases of up to 3–5 times prerifampin doses were required to maintain coagulation parameters in the therapeutic range. DOAC AUCs were decreased by 20%–67%, with variability by individual agent and with rifampin versus rifabutin. The active metabolite of clopidogrel increased substantially with rifampin coadministration, whereas prasugrel was largely unaffected and ticagrelor saw decreases. Our review suggests most combinations of AC/AP agents and rifampin are problematic. Further studies are required to determine whether rifabutin or rifapentine could be safe alternatives for coadministration with AC/AP drugs.  相似文献   
8.
Gastrointestinal (GI) cancers are a set of diverse diseases affecting many parts/ organs. The five most frequent GI cancer types are esophageal, gastric cancer (GC), liver cancer, pancreatic cancer, and colorectal cancer (CRC); together, they give rise to 5 million new cases and cause the death of 3.5 million people annually. We provide information about molecular changes crucial to tumorigenesis and the behavior and prognosis. During the formation of cancer cells, the genomic changes are microsatellite instability with multiple chromosomal arrangements in GC and CRC. The genomically stable subtype is observed in GC and pancreatic cancer. Besides these genomic subtypes, CRC has epigenetic modification (hypermethylation) associated with a poor prognosis. The pathway information highlights the functions shared by GI cancers such as apoptosis; focal adhesion; and the p21-activated kinase, phosphoinositide 3-kinase/Akt, transforming growth factor beta, and Toll-like receptor signaling pathways. These pathways show survival, cell proliferation, and cell motility. In addition, the immune response and inflammation are also essential elements in the shared functions. We also retrieved information on protein-protein interaction from the STRING database, and found that proteins Akt1, catenin beta 1 (CTNNB1), E1A binding protein P300, tumor protein p53 (TP53), and TP53 binding protein 1 (TP53BP1) are central nodes in the network. The protein expression of these genes is associated with overall survival in some GI cancers. The low TP53BP1 expression in CRC, high EP300 expression in esophageal cancer, and increased expression of Akt1/TP53 or low CTNNB1 expression in GC are associated with a poor prognosis. The Kaplan Meier plotter database also confirmed the association between expression of the five central genes and GC survival rates. In conclusion, GI cancers are very diverse at the molecular level. However, the shared mutations and protein pathways might be used to understand better and reveal diagnostic/prognostic or drug targets.  相似文献   
9.
BackgroundThe consistency in reporting the severity of drug interactions across the drug information resources is important in guiding the appropriate clinical use of drug-pairs, to minimize the associated adverse events. This necessitates the need of a standardized severity rating scale, that can accommodate the different severity ratings of the same interacting drug-pair into a reasonable severity category, that can ease the consistency assessment among different drug information resources.ObjectiveTo develop and validate a standardized severity rating scale that can ease the consistency assessment among the various drug information resources.MethodsThe definitions of various severity rating categories as documented in the eight drug information resources was consolidated to develop a standardized severity rating scale. Thus developed rating scale was validated using twenty commonly used drug-pairs. Fleiss' kappa score was used as an indicator for assessing overall consistency among various drug information resources, whereas, Cohen's kappa was used as an indicator of level of consistency between two drug information resources and between individual drug information resource and newly developed standardized severity rating scale.ResultsThe newly developed standardized severity rating scale classifies the severity of drug-drug interactions into three categories namely mild, moderate and major. The Fleiss' kappa score was improved from 0.047 to 0.176, indicating improved strength of agreement [Average pairwise agreement: 16% Vs 36.7%] among various drug information resources. The average pairwise Cohen's kappa was 0.082 [Strength of agreement: poor] in original severity ratings whereas it was improved to 0.198 [Strength of agreement: almost equal to fair] in standardized severity rating scale.ConclusionThe newly developed standardized severity rating scale can be used as a tool to assess the consistency of severity rating categories among the various drug information resources.  相似文献   
10.
《Drug discovery today》2022,27(1):246-256
Bromodomain-containing protein 4 (BRD4) is emerging as a therapeutic target that acts synergistically with other targets of small-molecule drugs in cancer. Therefore, the discovery of potential new dual-target inhibitors of BRD4 may be a promising strategy for cancer therapy. In this review, we highlight a series of strategies to design therapeutic dual-target inhibitors of BRD4 that focus on the synergistic functions of this protein. Drug combinations that exploit synthetic lethality, protein–protein interactions, functional complementarity, and blocking of resistance mechanisms could ultimately overcome the barriers inherent to the development of BRD4 inhibitors as future cancer drugs.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号