全文获取类型
收费全文 | 32391篇 |
免费 | 2131篇 |
国内免费 | 125篇 |
专业分类
耳鼻咽喉 | 490篇 |
儿科学 | 655篇 |
妇产科学 | 538篇 |
基础医学 | 5021篇 |
口腔科学 | 818篇 |
临床医学 | 3159篇 |
内科学 | 5989篇 |
皮肤病学 | 655篇 |
神经病学 | 3239篇 |
特种医学 | 1852篇 |
外科学 | 4711篇 |
综合类 | 307篇 |
一般理论 | 18篇 |
预防医学 | 1920篇 |
眼科学 | 1014篇 |
药学 | 2077篇 |
中国医学 | 37篇 |
肿瘤学 | 2147篇 |
出版年
2023年 | 154篇 |
2022年 | 290篇 |
2021年 | 674篇 |
2020年 | 411篇 |
2019年 | 586篇 |
2018年 | 699篇 |
2017年 | 529篇 |
2016年 | 685篇 |
2015年 | 798篇 |
2014年 | 1018篇 |
2013年 | 1248篇 |
2012年 | 2152篇 |
2011年 | 2090篇 |
2010年 | 1269篇 |
2009年 | 1245篇 |
2008年 | 1799篇 |
2007年 | 1964篇 |
2006年 | 1857篇 |
2005年 | 1809篇 |
2004年 | 1681篇 |
2003年 | 1488篇 |
2002年 | 1386篇 |
2001年 | 613篇 |
2000年 | 535篇 |
1999年 | 498篇 |
1998年 | 354篇 |
1997年 | 281篇 |
1996年 | 240篇 |
1995年 | 200篇 |
1994年 | 170篇 |
1993年 | 167篇 |
1992年 | 252篇 |
1991年 | 267篇 |
1990年 | 258篇 |
1989年 | 243篇 |
1988年 | 244篇 |
1987年 | 214篇 |
1986年 | 174篇 |
1985年 | 205篇 |
1984年 | 211篇 |
1983年 | 144篇 |
1982年 | 135篇 |
1981年 | 134篇 |
1979年 | 200篇 |
1978年 | 143篇 |
1977年 | 148篇 |
1976年 | 126篇 |
1974年 | 119篇 |
1973年 | 119篇 |
1972年 | 125篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
M.F. Werner A. López-Rueda F.X. Zarco J. Blasco L. San Román S. Amaro E. Carrero R. Valero L. Oleaga J.M. Macho N. Bargalló 《Radiologia》2019,61(2):143-152
Purpose
Endovascular treatment with mechanical thrombectomy devices demonstrated high recanalization rates but functional outcome did not correlate with high rates of recanalization obtained. Patient selection prior to the endovascular treatment is very important in the final outcome of the patient. The primary aim of our study was to evaluate the prognostic value of posterior circulation Alberta Stroke Program Early CT Score (pc-ASPECTS) and Pons-Midbrain Index (PMI) scores in patients with Basilar Artery Occlusion (BAO) treated with successful angiographic recanalization after mechanical thrombectomy.Methods
Retrospective single-center study including 18 patients between 2008 and 2013 who had acute basilar artery occlusion managed with endovascular treatment within 24 hours from symptoms onset and with successful angiographic recanalization. The patients were initially classified into two groups according to clinical outcome and mortality at 90 days. For analysis we also divided patients into groups based on pc-ASPECTS (≥8vs.< 8) and PMI (≥3vs.< 3) on non-contrast CT (NCCT) and CT Angiography Source Images (CTASI). Imaging data were correlated to clinical outcome and mortality rate.Results
CTASI pc-ASPECTS, dichotomized at < 8 versus≥8, was associated with a favorable outcome (RR: 2.6; 95% CI: 1.3-5.2) and a reduced risk of death (RR: 6.5: 95% CI: 7.8-23.3). All patients that survived and were functionally independent had pc-ASPECTS score≥8. None of the 5 patients with CTASI pc-ASPECTS score less than 8 survived.Conclusion
PC-ASPECTS on CTASI is helpful for predicting functional outcome after BAO recanalization with endovascular treatment. These results should be validated in a randomized controlled trial in order to decide whether or not to treat a patient with BAO. 相似文献2.
Weiyu Ye Anna Olsson-Brown Robert A. Watson Vincent T. F. Cheung Robert D. Morgan Isar Nassiri Rosalin Cooper Chelsea A. Taylor Umair Akbani Oliver Brain Rubeta N. Matin Nicholas Coupe Mark R. Middleton Mark Coles Joseph J. Sacco Miranda J. Payne Benjamin P. Fairfax 《British journal of cancer》2021,124(10):1661
Background Immune checkpoint blockers (ICBs) activate CD8+ T cells, eliciting both anti-cancer activity and immune-related adverse events (irAEs). The relationship of irAEs with baseline parameters and clinical outcome is unclear.Methods Retrospective evaluation of irAEs on survival was performed across primary (N = 144) and secondary (N = 211) independent cohorts of patients with metastatic melanoma receiving single agent (pembrolizumab/nivolumab—sICB) or combination (nivolumab and ipilimumab—cICB) checkpoint blockade. RNA from pre-treatment and post-treatment CD8+ T cells was sequenced and differential gene expression according to irAE development assessed.Results 58.3% of patients developed early irAEs and this was associated with longer progression-free (PFS) and overall survival (OS) across both cohorts (log-rank test, OS: P < 0.0001). Median survival for patients without irAEs was 16.6 months (95% CI: 10.9–33.4) versus not-reached (P = 2.8 × 10−6). Pre-treatment monocyte and neutrophil counts, but not BMI, were additional predictors of clinical outcome. Differential expression of numerous gene pathway members was observed in CD8+ T cells according to irAE development, and patients not developing irAEs demonstrating upregulated CXCR1 pre- and post-treatment.Conclusions Early irAE development post-ICB is associated with favourable survival in MM. Development of irAEs is coupled to expression of numerous gene pathways, suggesting irAE development in-part reflects baseline immune activation.Subject terms: Immunotherapy, Melanoma 相似文献
3.
4.
Brian C. Werner 《Arthroscopy》2019,35(4):1072-1073
Achieving tendon-bone healing continues to be challenging after arthroscopic rotator cuff repair, particularly for larger tears, despite significant improvements in repair techniques and implants. Considerable effort has been invested in research to identify methods to improve healing, including patches and injectable biologics. Parathyroid hormone improves tendon-to-bone healing. Teriparatide is osteogenic, stimulating bone growth, and chondrogenic, promoting cartilage formation at the enthesis. However, it could be difficult to justify the expense and potential risk of systemic administration of a recombinant hormone to improve structural healing until improvement in clinical outcomes can be shown. 相似文献
5.
A typical time series in functional magnetic resonance imaging (fMRI) exhibits autocorrelation, that is, the samples of the time series are dependent. In addition, temporal filtering, one of the crucial steps in preprocessing of functional magnetic resonance images, induces its own autocorrelation. While performing connectivity analysis in fMRI, the impact of the autocorrelation is largely ignored. Recently, autocorrelation has been addressed by variance correction approaches, which are sensitive to the sampling rate. In this article, we aim to investigate the impact of the sampling rate on the variance correction approaches. Toward this end, we first derived a generalized expression for the variance of the sample Pearson correlation coefficient (SPCC) in terms of the sampling rate and the filter cutoff frequency, in addition to the autocorrelation and cross‐covariance functions of the time series. Through simulations, we illustrated the importance of the variance correction for a fixed sampling rate. Using the real resting state fMRI data sets, we demonstrated that the data sets with higher sampling rates were more prone to false positives, in agreement with the existing empirical reports. We further demonstrated with single subject results that for the data sets with higher sampling rates, the variance correction strategy restored the integrity of true connectivity. 相似文献
6.
7.
8.
9.
Oliver Sartor MD Daniel Heinrich MD Neil Mariados MD Maria José Méndez Vidal MD Daniel Keizman MD Camilla Thellenberg Karlsson MD Avivit Peer MD Giuseppe Procopio MD Stephen J. Frank MD Kalevi Pulkkanen MD Eli Rosenbaum MD Stefano Severi MD José Trigo MD Lucia Trandafir MD Volker Wagner MD Rui Li MS Luke T. Nordquist MD 《The Prostate》2019,79(14):1683-1691
10.
Cécile Vicier Lillian Werner Jonathan Chipman Lauren C. Harshman Dattatraya H. Patil Raina N. Fichorova Jennifer R. Rider Martin G. Sanda Lorelei A. Mucci Christopher J. Sweeney 《Clinical genitourinary cancer》2019,17(1):32-37