全文获取类型
收费全文 | 25922篇 |
免费 | 3281篇 |
国内免费 | 1120篇 |
专业分类
耳鼻咽喉 | 147篇 |
儿科学 | 100篇 |
妇产科学 | 276篇 |
基础医学 | 2400篇 |
口腔科学 | 541篇 |
临床医学 | 2727篇 |
内科学 | 2902篇 |
皮肤病学 | 138篇 |
神经病学 | 975篇 |
特种医学 | 771篇 |
外国民族医学 | 8篇 |
外科学 | 2028篇 |
综合类 | 4419篇 |
现状与发展 | 7篇 |
一般理论 | 1篇 |
预防医学 | 2455篇 |
眼科学 | 529篇 |
药学 | 3240篇 |
74篇 | |
中国医学 | 3470篇 |
肿瘤学 | 3115篇 |
出版年
2024年 | 60篇 |
2023年 | 451篇 |
2022年 | 1036篇 |
2021年 | 1340篇 |
2020年 | 1333篇 |
2019年 | 853篇 |
2018年 | 882篇 |
2017年 | 689篇 |
2016年 | 832篇 |
2015年 | 1174篇 |
2014年 | 2233篇 |
2013年 | 1895篇 |
2012年 | 2737篇 |
2011年 | 2729篇 |
2010年 | 2175篇 |
2009年 | 1533篇 |
2008年 | 1258篇 |
2007年 | 1785篇 |
2006年 | 1267篇 |
2005年 | 695篇 |
2004年 | 609篇 |
2003年 | 475篇 |
2002年 | 414篇 |
2001年 | 321篇 |
2000年 | 264篇 |
1999年 | 289篇 |
1998年 | 141篇 |
1997年 | 155篇 |
1996年 | 131篇 |
1995年 | 99篇 |
1994年 | 100篇 |
1993年 | 62篇 |
1992年 | 81篇 |
1991年 | 73篇 |
1990年 | 70篇 |
1989年 | 34篇 |
1988年 | 33篇 |
1987年 | 6篇 |
1985年 | 1篇 |
1984年 | 2篇 |
1982年 | 3篇 |
1976年 | 1篇 |
1932年 | 1篇 |
1927年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 62 毫秒
11.
目的探讨分析对急性结石性胆囊炎患者采用腹腔镜胆囊切除术进行治疗的临床效果,以及对患者的胃肠功能和C反应蛋白所造成的影响。方法本次研究对象乃是我院肝胆外科于2017年4月-2019年4月期间收治的急性结石性胆囊炎患者62例,按照患者就诊的先后顺序对其进行平均分组,比较两组患者的术后肠鸣音恢复时间、肛门排气时间、排便时间、C反应蛋白水平以及并发症发生率。结果腹腔镜手术组患者的术后肠鸣音恢复时间(13.6±3.5)小时、肛门排气时间(16.5±2.7)小时以及排便时间(25.7±3.3)小时,均明显少于开腹式手术组患者(P<0.05);腹腔镜手术组患者的术后并发症发生率(6.45%)明显低于开腹式手术组患者(25.80%)(P<0.05);腹腔镜手术组患者的C反应蛋白水平为(10.4±2.5)mg/L,少于开腹式手术组患者(P<0.05)。结论根据本次研究的结果可以确认,对急性结石性胆囊炎患者采用腹腔镜胆囊切除术进行治疗能够取得更好的效果,可以促使患者的胃肠功能在术后更快的恢复,提高患者的C反应蛋白,从而有效避免患者出现并发症。 相似文献
12.
13.
目的:探讨MRI在浸润性小叶癌(ILC)术前诊断中的应用价值,并评估乳腺密度对其影响。方法:选取75例术前30天内行MRI检查的I-Ⅲ期ILC患者列入本项研究,根据腺体含量评估乳腺密度,在MRI下测量肿瘤大小,并对比其与病理大小的一致性。结果:75例入组患者中26例(34.7%)患者经MRI评估发现新的可疑病灶,20例(26.7%)患者改变了手术方式。高密度乳腺型患者额外病灶检出率明显高于低密度乳腺型患者(51.6% vs 22.7%,P=0.010)。MRI评估肿瘤大小在低密度乳腺型患者中容易被低估(36.4% vs 12.9%,P=0.024),在高密度乳腺型患者中容易被高估(6.8% vs 29.0%,P=0.010),但两组患者与病理大小一致性的比例无明显差异。结论:ILC患者术前乳腺MRI检查能够提高额外恶性肿瘤的检出率,而乳腺密度是影响MRI评估的重要因素。 相似文献
14.
Many nanoparticles (NPs) have toxic effects on multiple cell lines. This toxicity is assumed to be related to their accumulation within cells. However, the process of internalization of NPs has not yet been fully characterized. In this study, the cellular uptake, accumulation, and localization of titanium dioxide nanoparticles (TiO2 NPs) in rat (C6) and human (U373) glial cells were analyzed using time-lapse microscopy (TLM) and transmission electron microscopy (TEM). Cytochalasin D (Cyt-D) was used to evaluate whether the internalization process depends of actin reorganization. To determine whether the NP uptake is mediated by phagocytosis or macropinocytosis, nitroblue tetrazolium (NBT) reduction was measured and the 5-(N-ethyl-N-isopropyl)-amiloride was used. Expression of proteins involved with endocytosis and exocytosis such as caveolin-1 (Cav-1) and cysteine string proteins (CSPs) was also determined using flow cytometry.TiO2 NPs were taken up by both cell types, were bound to cellular membranes and were internalized at very short times after exposure (C6, 30 min; U373, 2 h). During the uptake process, the formation of pseudopodia and intracellular vesicles was observed, indicating that this process was mediated by endocytosis. No specific localization of TiO2 NPs into particular organelles was found: in contrast, they were primarily localized into large vesicles in the cytoplasm. Internalization of TiO2 NPs was strongly inhibited by Cyt-D in both cells and by amiloride in U373 cells; besides, the observed endocytosis was not associated with NBT reduction in either cell type, indicating that macropinocytosis is the main process of internalization in U373 cells. In addition, increases in the expression of Cav-1 protein and CSPs were observed.In conclusion, glial cells are able to internalize TiO2 NPs by a constitutive endocytic mechanism which may be associated with their strong cytotoxic effect in these cells; therefore, TiO2 NPs internalization and their accumulation in brain cells could be dangerous to human health. 相似文献
15.
孤独症谱系障碍(ASD)是影响儿童健康的严重公共问题之一,以社交沟通障碍、兴趣或活动范围狭窄以及重复刻板行为为特征。近年来越来越多的研究显示,ASD患儿维生素D(VitD)水平明显低于同龄健康儿童,VitD缺乏可能与ASD的发病机制相关。本文就VitD与ASD的相关研究进行综述。 相似文献
16.
《Clinics and research in hepatology and gastroenterology》2022,46(10):102012
BackgroundAlcoholic fatty liver disease (AFLD) is a liver disease caused by prolonged heavy drinking and has a poor prognosis in the clinic. This study aimed to explore the differential miRNAs expression profiles in the AFLD rat model.MethodsThe rat model of AFLD was established by ethanol intragastric administration and was used to explore the differential miRNAs expression profiles. We further analyzed the potential target mRNAs using the bioinformatics technique. GO and KEGG pathway enrichment analyses were carried out to better understand the biological function of differential expression genes (DEGs). We used the human Gene Expression Omnibus (GEO) dataset GSE28619 to further screen the key differentially expressed genes. The integration between the differentially expressed genes from the AFLD model and GEO was conducted and the key genes were identified.ResultsThe serum ALT, AST, TG, and TC levels in the AFLD model group were significantly higher than those in the normal control group. There are 45 miRNAs with significant changes including 26 upregulated and 19 down-regulated miRNAs. GO and KEGG enrichment showed various metabolic processes and signaling pathways were enriched in the progression of AFLD. After integrating the results of GSE28619 and DEGs, we observed that there are 12 genes with significant changes in two data sets, including PSAT1, TKFC, PTTG1, LCN2, CXCL1, NR4A1, RGS1, VCAN, FOS, CXCL10, ATF3, and CYP1A1.ConclusionAFLD showed differentially expressed miRNAs, which may be involved in the occurrence and progression of AFLD. Meanwhile, some signal metabolic pathways may be related to the pathogenesis of AFLD. 相似文献
17.
18.
19.
20.