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目的 提出基于舌象和形体特征的中医体质辨识模型,探讨中医以舌辨质客观化、规范化方法。方法 提取客观化的舌象特征(舌质与舌苔的色度和饱和度、舌苔纹理的平均亮度、平滑度以及齿痕特征)和形体特征,建立基于神经网络和支持向量机的客观化舌象和形体特征的辅助中医体质识别模型。结果 对平和质、气虚质、阴虚质和气淤质四种体质进行模型的训练和测试,结果表明融合舌象特征和形体特征的中医体质辨识模型能有效地辅助中医体质识别,且支持向量机对四种体质辨识效果总体上优于神经网络。结论 基于客观化的舌象特征和形体特征辅助中医体质辨识有利于提高中医体质辨识的客观化水平,合理选择机器学习算法可以提高中医体质辨识的准确性。  相似文献   
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The 12th International Food Data Conference (IFDC) was held in Buenos Aires, Argentina, from 11 to 13 October 2017. It was organized by Instituto Nacional de Investigaciones Biológica and International Network of Data System/FAO (INSIBIO and INFOODS/FAO) as a pre-conference of the 21th International Congress of Nutrition (ICN2017). The theme was “From Food Composition to Better Policies and Programmes in Nutrition and Agriculture”. A total of 152 delegates from 37 countries participated in the Conference. The programme included one keynote address, 46 oral presentations and 82 poster displays. The conference programme along with the Power Point files of the oral presentations are available on the conference website (http://www.ifdc2017.com/). The Conference was very successful, with high-quality scientific oral presentations and posters, and very satisfactory participation. The participants were able to exchange knowledge and personal experiences, and develop new ideas while discussing current research and other matters.  相似文献   
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Split liver transplantation (SLT) is 1 strategy for maximizing the number of deceased donor liver transplants. Recent reports suggest that utilization of SLT in the United States remains low. We examined deceased donor offers that were ultimately split between 2010 and 2014. SLTs were categorized as “primary” and “secondary” transplants. We analyzed allocation patterns and used logistic regression to evaluate factors associated with secondary split discard. Four hundred eighteen livers were split: 54% from adult, 46% from pediatric donors. Of the 227 adult donor livers split, 61% met United Network for Organ Sharing “optimal” split criteria. A total of 770 recipients (418 primary and 352 secondary) were transplanted, indicating 16% discard. Ninety‐two percent of the 418 primary recipients were children, and 47% were accepted on the first offer. Eighty‐seven percent of the 352 secondary recipients were adults, and 7% were accepted on the first offer. Of the 352 pairs, 99% were transplanted in the same region, 36% at the same center. In logistic regression, shorter donor height was associated with secondary discard (odds ratio 0.97 per cm, 95% CI 0.94‐1.00, P = .02). SLT volume by center was not predictive of secondary discard. Current policy proposals that incentivize SLT in the United States could increase the number of transplants to children and adults.  相似文献   
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《Annals of hepatology》2020,19(4):437-445
Introduction and objectivesThe prevalence of alcohol, tobacco, and coffee use and association with liver health among North Americans with Chronic Hepatitis B (CHB) infection has not been well described.Materials and methodsThe Hepatitis B Research Network includes an observational study of untreated CHB adults enrolled at 21 sites in the United States and Canada. Alcohol use was categorized as none, moderate, and at-risk based on the definition from the National Institute on Alcohol Abuse and Alcoholism; tobacco use as never, current and former; coffee use as none, 1–2 cups/day, and ≥3 cups/day. Linear regression and linear mixed models were used to associate lifestyle behaviors with ALT and FIB-4 values.Results1330 participants met eligibility: 53% males, 71% Asian and the median age was 42 years (IQR: 34–52). Median ALT was 33 U/L (IQR: 22–50), 37% had HBV DNA <103 IU/mL, 71% were HBeAg negative, and 65% had a FIB-4 <1.45. At baseline, 8% of participants were at-risk alcohol drinkers, 11% were current smokers and 92% drank <3 cups of coffee/day. Current tobacco and ‘at-risk’ alcohol use, were significantly associated with elevated ALT levels in univariable analyses, however, these associations were not statistically significant when controlling for sociodemographic and HBV characteristics.ConclusionsIn this large diverse cohort of untreated CHB participants, at-risk alcohol use, current tobacco use and limited coffee consumption did not have an association with high ALT and FIB-4 values. In contrast, significant associations were found between the frequency of these lifestyle behaviors and sociodemographic factors.  相似文献   
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BackgroundAlzheimer’s disease (AD) is a neurodegenerative disease that primarily manifests as progressive memory loss and cognitive impairment. Traditional herbal medicines may be helpful in the discovery of new anti-AD drugs. Studies have shown that Ferula assafoetida has neuroprotective and memory-enhancing effects, which may be beneficial for the treatment of AD. However, the combination of active ingredients and their mechanisms remain unclear. Therefore, we aimed to identify potential active ingredients in F. assafoetida and their mechanisms of action against AD by using network pharmacology.MethodsIn our study, an integrated network pharmacological approach, that included adsorption, distribution, metabolism and excretion screening, target identification, network construction, topological analysis, gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis, and molecular docking, was used to predict the pharmacological material basis and potential mechanisms through which these ingredients may treat and prevent AD.ResultsThe results indicated that 12 key active ingredients, obtained by topological analysis (including farnesiferol a, conferol, farnesiferol b, ferulic acid, etc.), may be the primary pharmacological components that may ameliorate AD. The 2 key significant pathways identified are the cholinergic synapse signaling pathway (critical targets include ACHE, CHRM1, CHRM2, MAPK1, PIK3CA, PIK3CB, PIK3CD, and PIK3CG) and the AD signaling pathway (critical targets include APP, BACE1, GSK3B, MAPK1, NCSTN, NOS1, PSEN1). These critical targets are closely related to the regulation of three typical pathological features of AD [central nervous system (CNS) cholinergic hypofunction, amyloid-β (Aβ) plaques, and hyperphosphorylated tau proteins]. Finally, 14 critical targets in the 2 key significant pathways were validated by molecular docking analysis.ConclusionF. assafoetida may be effective for alleviating AD symptoms, through multi-component, multi-target, and multi-pathway synergistic effects, associated with the multiple pathogenesis hypotheses of AD. Our study may provide certain clues for the further development and utilization of this natural herbal medicine.  相似文献   
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目的:目前青黛已是治疗急性幼粒细胞白血病(APL)的临床有效药物,但其分子机制与物质基础仍不明确。基于此本研究构建青黛与APL可视化药靶蛋白模型,以探究青黛作用于APL的分子机制。方法:通过GEO数据库检索APL微阵列芯片分析APL差异表达基因,使用TCMSP数据库筛选青黛活性成分,结合PubChem和SwissTargetPrediction匹配活性成分的靶基因并进行富集分析。String用于挖掘并构建APL可视化蛋白互作数据,将其读入Cytoscape,通过Centiscape实现网络拓扑分析。综合APL差异表达基因,通过Sybyl与青黛活性成分构建药靶蛋白模型。结果:筛选出3张APL微阵列芯片,164个差异表达基因,9种青黛活性成分,541个靶基因,这些靶点较多地参与细胞凋亡、药物结合、癌症途径、慢性粒细胞白血病等,这些都在APL中起重要作用。拓扑分析显示ELANE,CTSS为核心基因,将其与青黛9种活性成分进行药靶蛋白模型预测,显示靛玉红和靛蓝与核心基因结合度最佳。结论:APL是受多基因调控的复杂疾病,而青黛成分中靛玉红和靛蓝可通过结合ELANE,CTSS作用于APL的发生发展。  相似文献   
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