全文获取类型
收费全文 | 22610篇 |
免费 | 1587篇 |
国内免费 | 949篇 |
专业分类
耳鼻咽喉 | 216篇 |
儿科学 | 228篇 |
妇产科学 | 282篇 |
基础医学 | 3625篇 |
口腔科学 | 676篇 |
临床医学 | 1498篇 |
内科学 | 3044篇 |
皮肤病学 | 259篇 |
神经病学 | 1159篇 |
特种医学 | 1080篇 |
外国民族医学 | 4篇 |
外科学 | 5361篇 |
综合类 | 2675篇 |
现状与发展 | 7篇 |
预防医学 | 781篇 |
眼科学 | 190篇 |
药学 | 1246篇 |
21篇 | |
中国医学 | 295篇 |
肿瘤学 | 2499篇 |
出版年
2024年 | 77篇 |
2023年 | 518篇 |
2022年 | 884篇 |
2021年 | 1232篇 |
2020年 | 1158篇 |
2019年 | 923篇 |
2018年 | 778篇 |
2017年 | 681篇 |
2016年 | 708篇 |
2015年 | 795篇 |
2014年 | 1385篇 |
2013年 | 1559篇 |
2012年 | 1139篇 |
2011年 | 1332篇 |
2010年 | 1033篇 |
2009年 | 1151篇 |
2008年 | 1138篇 |
2007年 | 1128篇 |
2006年 | 998篇 |
2005年 | 897篇 |
2004年 | 783篇 |
2003年 | 716篇 |
2002年 | 557篇 |
2001年 | 513篇 |
2000年 | 405篇 |
1999年 | 385篇 |
1998年 | 323篇 |
1997年 | 285篇 |
1996年 | 241篇 |
1995年 | 210篇 |
1994年 | 169篇 |
1993年 | 164篇 |
1992年 | 112篇 |
1991年 | 105篇 |
1990年 | 93篇 |
1989年 | 62篇 |
1988年 | 67篇 |
1987年 | 73篇 |
1986年 | 50篇 |
1985年 | 67篇 |
1984年 | 63篇 |
1983年 | 24篇 |
1982年 | 40篇 |
1981年 | 39篇 |
1980年 | 33篇 |
1979年 | 14篇 |
1978年 | 20篇 |
1977年 | 6篇 |
1976年 | 7篇 |
1966年 | 2篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
The circadian rhythm in humans is determined by the central clock located in the hypothalamus’s suprachiasmatic nucleus, and it synchronizes the peripheral clocks in other tissues. Circadian clock genes and clock-controlled genes exist in almost all cell types. They have an essential role in many physiological processes, including lipid metabolism in the liver, regulation of the immune system, and the severity of infections. In addition, circadian rhythm genes can stimulate the immune response of host cells to virus infection. Hepatitis B virus (HBV) infection is the leading cause of liver disease and liver cancer globally. HBV infection depends on the host cell, and hepatocyte circadian rhythm genes are associated with HBV replication, survival, and spread. The core circadian rhythm proteins, REV-ERB and brain and muscle ARNTL-like protein 1, have a crucial role in HBV replication in hepatocytes. In addition to influencing the virus’s life cycle, the circadian rhythm also affects the pharmacokinetics and efficacy of antiviral vaccines. Therefore, it is vital to apply antiviral therapy at the appropriate time of day to reduce toxicity and improve the effectiveness of antiviral treatment. For these reasons, understanding the role of the circadian rhythm in the regulation of HBV infection and host responses to the virus provides us with a new perspective of the interplay of the circadian rhythm and anti-HBV therapy. Therefore, this review emphasizes the importance of the circadian rhythm in HBV infection and the optimization of antiviral treatment based on the circadian rhythm-dependent immune response. 相似文献
3.
4.
Jeffrey J. Silbiger 《Echocardiography (Mount Kisco, N.Y.)》2019,36(5):954-957
Secondary tricuspid regurgitation (TR) caused by right ventricular enlargement in the setting of left heart disease/pulmonary hypertension has been well described. In contrast, that associated with right atrial enlargement—atrial functional TR (AF‐TR)—remains largely underappreciated. AF‐TR most often occurs in the setting of lone atrial fibrillation, although it is also seen in its absence (idiopathic AF‐TR). Several recent studies have found that the prevalence, hemodynamic significance, and prognosis of AF‐TR are not inconsequential, suggesting increased physician awareness of this novel clinical entity is warranted. This article discusses the pathogenesis, echocardiographic findings, and treatment of this underappreciated cause of secondary TR. 相似文献
5.
6.
7.
Tianying Yang Jiawei Li Yichen Jia Chunchen Yang Ruirui Sang Tongyu Zhu Ming Xu Ruiming Rong Cheng Yang 《Translational andrology and urology》2021,10(1):204
BackgroundIn the field of transplantation, inducing immune tolerance in recipients is of great importance. Blocking co-stimulatory molecule using anti-CD28 antibody could induce tolerance in a rat kidney transplantation model. Myeloid-derived suppressor cells (MDSCs) reveals strong immune suppressive abilities in kidney transplantation. Here we analyzed key genes of MDSCs leading to transplant tolerance in this model.MethodsMicroarray data of rat gene expression profiles under accession number in the Gene Expression Omnibus (GEO) database were analyzed. Running the LIMMA package in R language, the differentially expressed genes (DEGs) were found. Enrichment analysis of the DEGs was conducted in the Database for Annotation, Visualization and Integrated Discovery (DAVID) database to explore gene ontology (GO) annotation and their Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Their protein-protein interactions (PPIs) were provided by STRING database and was visualized in Cytoscape. Hub genes were carried out by CytoHubba.ResultsThree hundred and thirty-eight DEGs were exported, including 27 upregulated and 311 downregulated genes. The functions and KEGG pathways of the DEGs were assessed and the PPI network was constructed based on the string interactions of the DEGs. The network was visualized in Cytoscape; the entire PPI network consisted of 192 nodes and 469 edges. Zap70, Cdc42, Stat1, Stat4, Ccl5 and Cxcr3 were among the hub genes.ConclusionsThese key genes, corresponding proteins and their functions may provide valuable background for both basic and clinical research and could be the direction of future studies in immune tolerance, especially those examining immunocyte-induced tolerance. GSE28545相似文献
8.
《Journal of vascular surgery》2020,71(6):1921-1929
ObjectiveIdentifying biomarkers for abdominal aortic aneurysms (AAA) could prove beneficial in prognosis of AAA and thus the selection for treatment. Microfibrillar-associated protein 4 (MFAP4) is an extracellular matrix protein that is highly expressed in aorta. MFAP4 is involved in several tissue remodeling-related diseases. We aimed to investigate the potential role of plasma MFAP4 (pMFAP4) as a biomarker of AAA.MethodsPlasma samples and data were obtained for 504 male AAA patients and 188 controls in the Viborg Vascular (VIVA) screening trial. The pMFAP4 levels were measured by Alphalisa. The Mann-Whitney U test assessed differences in pMFAP4 levels between the presence and absence of different exposures of interest. The correlation between pMFAP4 and aorta growth rate were investigated through spearman's correlation analysis. Immunohistochemistry and multiple logistic regression adjusted for potential confounders assessed the association between pMFAP4 and AAA. Multiple linear regression assessed the correlation between pMFAP4 and aorta growth rate. Cox regression and competing risk regression were used to investigate the correlation between AAA patients with upper tertile pMFAP4 and the risk of undergoing later surgical repair.ResultsA significant negative correlation between pMFAP4 and aorta growth rate was observed using spearman's correlation analysis (ρ = −0.14; P = .0074). However, this finding did not reach significance when applying multiple linear regression. A tendency of decreased pMFAP4 was observed in AAA using immunohistochemistry. Competing risk regression adjusted for potential confounders indicated that patients with upper tertile pMFAP4 had a hazard ratio of 0.51 (P = .001) for risk of undergoing later surgical repair.ConclusionsHigh levels of pMFAP4 are associated with a decreased likelihood of receiving surgical repair in AAA. This observation warrants confirmation in an independent cohort. 相似文献
9.
10.
目的 探讨一次性根管与常规根管治疗后冠修复对隐裂性牙髓炎患者的治疗效果。方法 选取2014年5月至2017年5月诊治的187例隐裂性牙髓炎患者随机分为观察组和对照组,观察组给予一次性根管治疗后冠修复,对照组给予常规根管治疗后冠修复,比较两组术前及术后1周Mohd Sulong疼痛分级、术后3个月临床疗效、术后6个月X线改变、术后2年治疗成功率。结果 术前两组Mohd Sulong疼痛分级无统计学差异(P>0.05),冠修复术后1周两组疼痛分级无统计学差异(P>0.05),术后3个月观察组临床疗效总有效率为97.83%较对照组88.41%显著提高(P<0.05),术后6个月观察X线改变率为3.26%较对照组14.74%显著降低(P<0.05),术后2年观察组治疗成功率为94.57%较对照组82.11%显著提高(P<0.05)。结论 一次性根管治疗后冠修复能够缓解隐裂性牙髓炎疼痛,提高临床疗效,提高患者咀嚼功能和生活质量,值得在临床上推广。 相似文献