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   14279篇
  免费   1105篇
  国内免费   524篇
耳鼻咽喉   71篇
儿科学   439篇
妇产科学   193篇
基础医学   1496篇
口腔科学   121篇
临床医学   1078篇
内科学   1717篇
皮肤病学   194篇
神经病学   1020篇
特种医学   670篇
外国民族医学   1篇
外科学   1100篇
综合类   2083篇
现状与发展   1篇
预防医学   1537篇
眼科学   301篇
药学   2158篇
  9篇
中国医学   724篇
肿瘤学   995篇
  2024年   36篇
  2023年   171篇
  2022年   317篇
  2021年   568篇
  2020年   401篇
  2019年   347篇
  2018年   375篇
  2017年   443篇
  2016年   528篇
  2015年   544篇
  2014年   879篇
  2013年   1245篇
  2012年   878篇
  2011年   988篇
  2010年   816篇
  2009年   713篇
  2008年   745篇
  2007年   697篇
  2006年   699篇
  2005年   622篇
  2004年   538篇
  2003年   467篇
  2002年   344篇
  2001年   328篇
  2000年   261篇
  1999年   196篇
  1998年   171篇
  1997年   165篇
  1996年   156篇
  1995年   115篇
  1994年   120篇
  1993年   96篇
  1992年   111篇
  1991年   88篇
  1990年   74篇
  1989年   77篇
  1988年   74篇
  1987年   57篇
  1986年   50篇
  1985年   61篇
  1984年   57篇
  1983年   56篇
  1982年   38篇
  1981年   43篇
  1980年   36篇
  1979年   35篇
  1978年   18篇
  1977年   15篇
  1976年   14篇
  1974年   9篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.

Objective

To assay peripheral inter-ictal cytokine serum levels and possible relations with non-invasive vagus nerve stimulation (nVNS) responsiveness in migraineurs.

Methods

This double-blinded, sham-controlled study enrolled 48 subjects and measured headache severity, frequency [headache days/month, number of total and mild/moderate/severe classified attacks/month], functional state [sleep, mood, body weight, migraine-associated disability] and serum levels of inflammatory markers [inter-ictal] using enzyme-linked immunoassays at baseline and after 2 months of adjunctive nVNS compared to sham stimulation and suitably matched controls.

Results

No significant differences were observed at baseline and after 2 months for headache severity, total attacks/month, headache days/month and functional outcome [sleep, mood, disability] between verum and sham nVNS. However, the number of severe attacks/month significantly decreased in the verum nVNS group and circulating pro-inflammatory IL-1β was elevated significantly in the sham group compared to nVNS. Levels of anti-inflammatory IL-10 were significantly higher at baseline in both groups compared to healthy controls, but not at 2 months follow-up [p?<?0.05]. Concentrations of high-mobility group box-1 (HMGB-1), IL-6, tumor-necrosis factor-α (TNF-α), leptin, adiponectin, ghrelin remained unchanged [p?>?0.05]. No severe device-/stimulation-related adverse events occurred.

Conclusion

2 months of adjunctive cervical nVNS significantly declined the number of severe attacks/month. Pro-inflammatory IL-1β plasma levels [inter-ictal] were higher in sham-treated migraine patients compared to verum nVNS. However, pro- [IL-6, HMGB-1, TNF-α, leptin] and anti-inflammatory [IL-10, adiponectin, ghrelin] mediators did not differ statistically. Profiling of neuroinflammatory circuits in migraine to predict nVNS responsiveness remains an experimental approach, which may be biased by pre-analytic variables warranting large-scale biobank-based systematic investigations [omics].  相似文献   
4.
5.
《Vaccine》2020,38(33):5337-5342
Freezing of alum-based vaccines drastically alters their colloidal composition and leads to irreversible cluster formation. The loss of stability is well described, but the impact of frost damage on the functionality of the induced and secreted antibody repertoire has not been studied in detail. We therefore applied our single-cell measurement platform to extract the frequencies of Immunoglobulin G-secreting cells in combination with individual secretion rates and affinities. We showed that, frost-damaged or not, the tested vaccine was able to generate similar frequencies of total and antigen-affine IgG-secreting cells. Additionally, the frost-damaged vaccine stimulated a similar T-cell cytokine secretion pattern when compared to the regularly stored vaccine. However, frost-damaged vaccines induced no efficient affinity maturation and a complete collapse of the affinity distribution was observed. This study unveiled the impact of frost-damage to alum-based vaccines on the induced secreted antibody repertoire, and illustrated the power of functional single-antibody analysis.  相似文献   
6.
7.
8.
新型冠状病毒肺炎(corona virus disease 2019,COVID-19)自2019年12月爆发以来,由于具有高传染性,迅速在世界各地蔓延,国内外疫情防治形势空前严峻。COVID-19不仅造成肺部、肠道、肾脏等多脏器损害,且部分患者以眼表损害为首发或伴发症状出现,临床上很容易被忽视。COVID-19的眼表损害归属于祖国医学“天行赤眼”范畴,本文结合国内外最新的文献报道,探讨新型冠状病毒(2019 novel corona virus,2019-nCoV)对眼表的损害,阐明其可能机制,并从中西医角度提出可行的治疗措施。  相似文献   
9.
ABSTRACT

Genotoxic compounds may be detoxified to non-genotoxic metabolites while many pro-carcinogens require metabolic activation to exert their genotoxicity in vivo. Standard genotoxicity assays were developed and utilized for risk assessment for over 40 years. Most of these assays are conducted in metabolically incompetent rodent or human cell lines. Deficient in normal metabolism and relying on exogenous metabolic activation systems, the current in vitro genotoxicity assays often have yielded high false positive rates, which trigger unnecessary and costly in vivo studies. Metabolically active cells such as hepatocytes have been recognized as a promising cell model in predicting genotoxicity of carcinogens in vivo. In recent years, significant advances in tissue culture and biological technologies provided new opportunities for using hepatocytes in genetic toxicology. This review encompasses published studies (both in vitro and in vivo) using hepatocytes for genotoxicity assessment. Findings from both standard and newly developed genotoxicity assays are summarized. Various liver cell models used for genotoxicity assessment are described, including the potential application of advanced liver cell models such as 3D spheroids, organoids, and engineered hepatocytes. An integrated strategy, that includes the use of human-based cells with enhanced biological relevance and throughput, and applying the quantitative analysis of data, may provide an approach for future genotoxicity risk assessment.  相似文献   
10.
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