全文获取类型
收费全文 | 22080篇 |
免费 | 2123篇 |
国内免费 | 1284篇 |
专业分类
耳鼻咽喉 | 198篇 |
儿科学 | 277篇 |
妇产科学 | 416篇 |
基础医学 | 2011篇 |
口腔科学 | 433篇 |
临床医学 | 2944篇 |
内科学 | 2917篇 |
皮肤病学 | 253篇 |
神经病学 | 974篇 |
特种医学 | 677篇 |
外国民族医学 | 8篇 |
外科学 | 1444篇 |
综合类 | 4474篇 |
现状与发展 | 10篇 |
一般理论 | 1篇 |
预防医学 | 2046篇 |
眼科学 | 556篇 |
药学 | 2768篇 |
17篇 | |
中国医学 | 1733篇 |
肿瘤学 | 1330篇 |
出版年
2024年 | 75篇 |
2023年 | 322篇 |
2022年 | 797篇 |
2021年 | 1026篇 |
2020年 | 823篇 |
2019年 | 609篇 |
2018年 | 636篇 |
2017年 | 689篇 |
2016年 | 618篇 |
2015年 | 971篇 |
2014年 | 1229篇 |
2013年 | 1280篇 |
2012年 | 1832篇 |
2011年 | 1920篇 |
2010年 | 1467篇 |
2009年 | 1241篇 |
2008年 | 1475篇 |
2007年 | 1362篇 |
2006年 | 1313篇 |
2005年 | 1110篇 |
2004年 | 803篇 |
2003年 | 715篇 |
2002年 | 662篇 |
2001年 | 496篇 |
2000年 | 409篇 |
1999年 | 311篇 |
1998年 | 179篇 |
1997年 | 186篇 |
1996年 | 139篇 |
1995年 | 139篇 |
1994年 | 101篇 |
1993年 | 67篇 |
1992年 | 89篇 |
1991年 | 78篇 |
1990年 | 62篇 |
1989年 | 53篇 |
1988年 | 47篇 |
1987年 | 35篇 |
1986年 | 35篇 |
1985年 | 17篇 |
1984年 | 11篇 |
1983年 | 7篇 |
1982年 | 7篇 |
1981年 | 7篇 |
1977年 | 5篇 |
1976年 | 3篇 |
1975年 | 3篇 |
1974年 | 3篇 |
1973年 | 4篇 |
1972年 | 4篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
51.
目的探讨参龟培元颗粒对重症肌无力(myastheniagravis,MG)的治疗作用。方法采用合成电鳗乙酰胆碱受体α亚单位125-147段多肽介导的实验性自身免疫性重症肌无力(experimentalautoimmunemyastheniagravis,EAMG)大鼠模型,研究参龟培元颗粒对造模大鼠临床症状、肌电与收缩力、血清AchR-Ab滴度及细胞因子TNF-α、IFN-γ含量的影响。结果参龟培元颗粒(16.0,8.0g/kg)可明显改善大鼠的肌无力症状,降低血清AchR-Ab滴度及TNF-α、IFN-γ含量,且对低频刺激引起的造模大鼠肌电衰减和肌肉收缩力的衰减具有显著的改善作用。结论参龟培元颗粒对大鼠EAMG有一定的治疗作用。 相似文献
52.
目的:自我干预强化点检表对前列腺手术患者自护能力与心理韧性及并发症的影响。方法:选取2019年5月~2021年6月在我院126例前列腺手术患者作为研究对象,按照随机数字表法分为对照组(予以常规护理干预)与观察组(在常规护理干预的基础上予以自我干预强化点检表),各63例,对比自我护理能力测定量表(ESCA)、心理韧性量表;观察并发症(尿路感染、尿道狭窄、尿潴留、尿失禁、尿频)。结果:入院时,两组患者 ESCA评分、心理韧性评分(坚韧、乐观、自强)比较差异无统计学意义;出院后3个月,观察组的ESCA评分、心理韧性评分(坚韧、乐观、自强)高于对照组。观察组患者的并发症总发生率低于对照组。结论:自我干预强化点检表有利于提高前列腺手术患者的自护能力与心理韧性,以及降低并发症发生率。 相似文献
53.
Shao-Huan Lan Chih-Cheng Lai Shen-Peng Chang Li-Chin Lu Shun-Hsing Hung Wei-Ting Lin 《Medicine》2022,101(27)
Background:The aim of this study was to investigate the clinical effect and safety of accelerated-strategy initiation of renal replacement therapy (RRT) in critically ill patients.Methods:PubMed, Embase, OVID, EBSCO, and the Cochrane Library databases were searched for relevant articles from inception to December 30, 2020. Only RCTs that compared the clinical efficacy and safety between accelerated-strategy RRT and standard-strategy RRT among critically ill adult patients with acute kidney injury (AKI) were included. The primary outcome was 28-day mortality.Results:A total of 5279 patients in 12 RCTs were included in this meta-analysis. The 28-day mortality rates of patients treated with accelerated and standard RRT were 37.3% (969/2596) and 37.9% (976/2573), respectively. No significant difference was observed between the groups (OR, 0.92; 95% CI, 0.70–1.12; I2 = 60%). The recovery rates of renal function were 54.5% and 52.5% in the accelerated- and standard-RRT groups, respectively, with no significant difference (OR, 1.03; 95% CI, 0.89–1.19; I2 = 56%). The rate of RRT dependency was similar in the accelerated- and standard-RRT strategies (6.7% vs 5.0%; OR, 1.11; 95% CI, 0.71–1.72; I2 = 20%). The accelerated-RRT group displayed higher risks of hypotension, catheter-related infection, and hypophosphatemia than the standard-RRT group (hypotension: OR, 1.26; 95% CI, 1.10–1.45; I2 = 36%; catheter-related infection: OR, 1.90; 95% CI, 1.17–3.09; I2 = 0%; hypophosphatemia: OR, 2.11; 95% CI, 1.43–3.15; I2 = 67%).Conclusions:Accelerated RRT does not reduce the risk of death and does not improve the recovery of kidney function among critically ill patients with AKI. In contrast, an increased risk of adverse events was observed in patients receiving accelerated RRT. However, these findings were based on low quality of evidence. Further large-scale RCTs is warranted. 相似文献
54.
Longyu Wang Haoyang Li Xiao Wang Xiaofeng Liu Weiqing Ma Guangji Zhou Qiaochu Liang Huixia Lan 《RSC advances》2022,12(32):20983
In this study, the effect of pH shock during the treatment of sulfate-containing organic wastewater was investigated using an anaerobic fermentation system reinforced with graphene oxide (GO)/iron series systems. The results show that the anaerobic system with the GO/iron series systems exhibited enhanced resistance to pH shock. Among them, the GO/Fe0 system had the strongest resistance to pH shock, the systems of GO/Fe3O4 and GO/Fe2O3 followed close behind, while the blank system performed the worst. After pH shock, the CODCr removal rate, SO42− removal rate, and gas production of the GO/Fe0 group were significantly improved compared with those of the control group by 51.0%, 65.3%, and 34.6%, respectively, while the accumulation of propionic acid was the lowest. Further, detailed microbial characterization revealed that the introduction of the GO/iron series systems was beneficial to the formation of more stable anaerobic co-metabolic flora in the system, and the relative abundance of Geobacter, Clostridium, Desulfobulbus and Desulfovibrio increased after acidic and alkaline shock.In this paper, we studied the pH shock resistance mechanism of GO/iron series from the perspectives of the treatment effect, changes in effluent pH and VFA, and microbial co-metabolic stability, providing a reference for the practical application. 相似文献
55.
Cardiovascular disease (CVD) is a group of diseases affecting the heart and blood vessels and is the leading cause of morbidity and mortality worldwide. Increasingly more evidence has shown that the senescence of vascular endothelial cells is the key to endothelial dysfunction and cardiovascular diseases. Anthocyanin is a type of water-soluble polyphenol pigment and secondary metabolite of plant-based food widely existing in fruits and vegetables. The gut microbiome is involved in the metabolism of anthocyanins and mediates the biological activities of anthocyanins and their metabolites, while anthocyanins also regulate the growth of specific bacteria in the microbiota and promote the proliferation of healthy anaerobic flora. Accumulating studies have shown that anthocyanins have antioxidant, anti-inflammatory, and anti-aging effects. Many animal and in vitro experiments have also proven that anthocyanins have protective effects on cardiovascular-disease-related dysfunction. However, the molecular mechanism of anthocyanin in eliminating aging endothelial cells and preventing cardiovascular diseases is very complex and is not fully understood. In this systematic review, we summarize the metabolism and activities of anthocyanins, as well as their effects on scavenging senescent cells and cardioprotection. 相似文献
56.
Effects of organophosphorus pesticides and their ozonation byproducts on gap junctional intercellular communication in rat liver cell line. 总被引:2,自引:0,他引:2
Jiguo Wu Li Lin Tiangang Luan Yuk Sing Chan Gilbert Chongyu Lan 《Food and chemical toxicology》2007,45(10):2057-2063
The effects of organophosphorus pesticides (OPs), oxons and their ozonation byproducts on gap junctional intercellular communication (GJIC) on cultured BRL cell line were investigated using scrape loading and dye transfer (SL/DT) technique. The neutral red uptake assay was used to identify the non-cytotoxic levels of diazinon, parathion and methyl-parathion applied to GJIC assay. The concentration-dependent inhibition of GJIC was observed over a range of 50-350 mg/l diazinon, parathion and methyl-parathion after 90 min incubation compared with the vehicle control. However, oxons and ozonation byproducts of OPs had no inhibition effect on GJIC at any of the concentrations tested. The inhibition of GJIC by OPs was reversible after removal of the tested pesticides followed by incubation with fresh medium. The present study suggested that the ozonation treatment could be used for the detoxification of drinking water and food crops contaminated with diazinon, parathion and methyl-parathion without formation of GJIC toxicity. 相似文献
57.
-组新的N-羟基肉桂酰胺类组蛋白去乙酰化酶抑制剂的合成和初步活性研究 总被引:1,自引:0,他引:1
目的 设计合成了一组新的N-羟基肉桂酰胺类衍生物并测定其对组蛋白去乙酰化酶(HDACs)的抑制活性.方法 以阿魏酸为原料,经酯化、Williamson反应、皂化、缩合4步反应合成了一组新的N-羟基肉桂酰胺类衍生物;用组蛋白去乙酰化酶活性检测试剂盒测定该组化合物体外抑酶活性.结果 与结论 合成了11个未见文献报道的N-羟基肉桂酰胺类衍生物,其结构经过1H-NMR、MS、和IR确认.其中化合物5a、5b、5e和5k的体外抑酶活性较强(IC50=2~15μmol·L-1),有可能具有抗肿瘤活性,值得进一步研究. 相似文献
58.
<正> 相似文献
59.
60.