收费全文 | 2037篇 |
免费 | 115篇 |
国内免费 | 10篇 |
耳鼻咽喉 | 43篇 |
儿科学 | 64篇 |
妇产科学 | 41篇 |
基础医学 | 253篇 |
口腔科学 | 107篇 |
临床医学 | 163篇 |
内科学 | 450篇 |
皮肤病学 | 26篇 |
神经病学 | 87篇 |
特种医学 | 55篇 |
外科学 | 359篇 |
综合类 | 62篇 |
预防医学 | 150篇 |
眼科学 | 39篇 |
药学 | 168篇 |
中国医学 | 24篇 |
肿瘤学 | 71篇 |
2023年 | 17篇 |
2022年 | 86篇 |
2021年 | 104篇 |
2020年 | 56篇 |
2019年 | 78篇 |
2018年 | 94篇 |
2017年 | 60篇 |
2016年 | 53篇 |
2015年 | 66篇 |
2014年 | 86篇 |
2013年 | 99篇 |
2012年 | 133篇 |
2011年 | 146篇 |
2010年 | 66篇 |
2009年 | 67篇 |
2008年 | 105篇 |
2007年 | 104篇 |
2006年 | 88篇 |
2005年 | 93篇 |
2004年 | 87篇 |
2003年 | 53篇 |
2002年 | 52篇 |
2001年 | 37篇 |
2000年 | 35篇 |
1999年 | 37篇 |
1998年 | 7篇 |
1997年 | 9篇 |
1996年 | 9篇 |
1995年 | 9篇 |
1994年 | 8篇 |
1993年 | 9篇 |
1992年 | 22篇 |
1991年 | 17篇 |
1990年 | 9篇 |
1989年 | 10篇 |
1988年 | 10篇 |
1987年 | 15篇 |
1986年 | 15篇 |
1985年 | 12篇 |
1984年 | 10篇 |
1983年 | 8篇 |
1982年 | 13篇 |
1981年 | 6篇 |
1980年 | 6篇 |
1979年 | 7篇 |
1978年 | 7篇 |
1977年 | 6篇 |
1973年 | 4篇 |
1971年 | 5篇 |
1967年 | 4篇 |
Our recent study has established that young blood factors are not causal, nor necessary, for the systemic rejuvenation of mammalian tissues. Instead, a procedure referred to as neutral blood exchange (NBE) that resets signaling milieu to a pro-regenerative state through dilution of old plasma, enhanced the health and repair of the muscle and liver, and promoted better hippocampal neurogenesis in 2-year-old mice (Mehdipour et al., Aging 12:8790–8819, 2020). Here we expand the rejuvenative phenotypes of NBE, focusing on the brain. Namely, our results demonstrate that old mice perform much better in novel object and novel texture (whisker discrimination) tests after a single NBE, which is accompanied by reduced neuroinflammation (less-activated CD68+ microglia). Evidence against attenuation/dilution of peripheral senescence-associated secretory phenotype (SASP) as the main mechanism behind NBE was that the senolytic ABT 263 had limited effects on neuroinflammation and did not enhance hippocampal neurogenesis in the old mice. Interestingly, peripherally acting ABT 263 and NBE both diminished SA-βGal signal in the old brain, demonstrating that peripheral senescence propagates to the brain, but NBE was more robustly rejuvenative than ABT 263, suggesting that rejuvenation was not simply by reducing senescence. Explaining the mechanism of the positive effects of NBE on the brain, our comparative proteomics analysis demonstrated that dilution of old blood plasma yields an increase in the determinants of brain maintenance and repair in mice and in people. These findings confirm the paradigm of rejuvenation through dilution of age-elevated systemic factors and extrapolate it to brain health and function.
相似文献Introduction and objectives
The PARIS score allows combined stratification of ischemic and hemorrhagic risk in patients with ischemic heart disease treated with coronary stenting and dual antiplatelet therapy (DAPT). Its usefulness in patients with acute coronary syndrome (ACS) treated with ticagrelor or prasugrel is unknown. We investigated this issue in an international registry.Methods
Retrospective multicenter study with voluntary participation of 11 centers in 6 European countries. We studied 4310 patients with ACS discharged with DAPT with ticagrelor or prasugrel. Ischemic events were defined as stent thrombosis or spontaneous myocardial infarction, and hemorrhagic events as BARC (Bleeding Academic Research Consortium) type 3 or 5 bleeding. Discrimination and calibration were calculated for both PARIS scores (PARISischemic and PARIShemorrhagic). The ischemic-hemorrhagic net benefit was obtained by the difference between the predicted probabilities of ischemic and bleeding events.Results
During a period of 17.2 ± 8.3 months, there were 80 ischemic events (1.9% per year) and 66 bleeding events (1.6% per year). PARISischemic and PARIShemorrhagic scores were associated with a risk of ischemic events (sHR, 1.27; 95%CI, 1.16-1.39) and bleeding events (sHR, 1.14; 95%CI, 1.01-1.30), respectively. The discrimination for ischemic events was modest (C index = 0.64) and was suboptimal for hemorrhagic events (C index = 0.56), whereas calibration was acceptable for both. The ischemic-hemorrhagic net benefit was negative (more hemorrhagic events) in patients at high hemorrhagic risk, and was positive (more ischemic events) in patients at high ischemic risk.Conclusions
In patients with ACS treated with DAPT with ticagrelor or prasugrel, the PARIS model helps to properly evaluate the ischemic-hemorrhagic risk. 相似文献Purpose of Review
Periprosthetic joint infection (PJI) is a devastating complication after total joint replacement. A main source for antibiotic tolerance and treatment failure is bacterial production of biofilm—a resilient barrier against antibiotics, immune system, and mechanical debridement. The purpose of this review is to explore some novel approaches to treat PJI and biofilm-related infections.Recent Findings
Innovative treatment strategies of bacterial and biofilm infections revolve around (a) augmenting current therapies, such as improving the delivery and efficiency of conventional antibiotics and enhancing the efficacy of antiseptics and (b) administrating completely new therapeutic modalities, such as using immunotherapy, nanoparticles, lytic bacteriophages, photodynamic therapy, novel antibiotics, and antimicrobial peptides.Summary
Several promising treatment strategies for PJI are available to be tested further. The next requirement for most of the novel treatments is reproducing their effects in clinically representative animal models of PJI against clinical isolates of relevant bacteria.Distinguishing between fibrotic and inflammatory strictures in Crohn’s disease (CD) is still challenging. The capacity of diffusion-weighted (DWI) magnetic resonance (MRE) to identify intestinal fibrosis was recently demonstrated; however, the therapeutic implications of this association have never been evaluated. The aim of the current study was to identify imaging features, including DWI, which can predict response to anti-inflammatory treatment in patients with stricturing CD.
MethodsConsecutive CD patients with intestinal strictures that initiated treatment with anti-tumor necrosis alpha (anti-TNF) between June 2012 and April 2017 with MRE adjacent to treatment onset were retrospectively collected. The primary outcome was treatment failure, defined as drug discontinuation, CD-related surgery, or endoscopic dilatation of the stricture. Clinical, demographic, and imaging data were compared between patients who did and did not develop treatment failure within 12 months of anti-TNF treatment initiation.
ResultsA total of 21 patients were included in the study; 9/21 (42.8%) developed treatment failure. None of the clinical/demographic parameters were associated with the risk of treatment failure. Among imaging parameters, only ADC value (< 1 × 10−3 mm2/s) was significantly associated with the risk of treatment failure (AUC = 0.81, 66% vs. 0%, p = 0.015).
ConclusionsOur results suggest that ADC value on DWI MRE may predict the risk of treatment failure in stricturing CD. If replicated in larger studies, these results may guide therapeutic decisions and suggest avoiding anti-TNF treatment.
相似文献