全文获取类型
收费全文 | 8228篇 |
免费 | 496篇 |
国内免费 | 35篇 |
专业分类
耳鼻咽喉 | 68篇 |
儿科学 | 282篇 |
妇产科学 | 205篇 |
基础医学 | 1265篇 |
口腔科学 | 174篇 |
临床医学 | 719篇 |
内科学 | 1690篇 |
皮肤病学 | 254篇 |
神经病学 | 873篇 |
特种医学 | 168篇 |
外科学 | 638篇 |
综合类 | 68篇 |
一般理论 | 3篇 |
预防医学 | 666篇 |
眼科学 | 186篇 |
药学 | 808篇 |
中国医学 | 12篇 |
肿瘤学 | 680篇 |
出版年
2024年 | 6篇 |
2023年 | 58篇 |
2022年 | 180篇 |
2021年 | 352篇 |
2020年 | 204篇 |
2019年 | 221篇 |
2018年 | 280篇 |
2017年 | 195篇 |
2016年 | 279篇 |
2015年 | 280篇 |
2014年 | 321篇 |
2013年 | 465篇 |
2012年 | 694篇 |
2011年 | 679篇 |
2010年 | 355篇 |
2009年 | 304篇 |
2008年 | 485篇 |
2007年 | 528篇 |
2006年 | 506篇 |
2005年 | 462篇 |
2004年 | 481篇 |
2003年 | 413篇 |
2002年 | 390篇 |
2001年 | 52篇 |
2000年 | 48篇 |
1999年 | 44篇 |
1998年 | 56篇 |
1997年 | 51篇 |
1996年 | 41篇 |
1995年 | 23篇 |
1994年 | 28篇 |
1993年 | 23篇 |
1992年 | 22篇 |
1991年 | 18篇 |
1990年 | 13篇 |
1989年 | 23篇 |
1988年 | 13篇 |
1987年 | 11篇 |
1986年 | 10篇 |
1985年 | 15篇 |
1984年 | 10篇 |
1983年 | 13篇 |
1982年 | 13篇 |
1981年 | 10篇 |
1980年 | 6篇 |
1979年 | 10篇 |
1978年 | 9篇 |
1977年 | 12篇 |
1975年 | 6篇 |
1974年 | 6篇 |
排序方式: 共有8759条查询结果,搜索用时 328 毫秒
1.
2.
3.
4.
5.
Enrique Luengo Izaskun Buendia Cristina Fernndez‐Mendívil Paula Trigo‐Alonso Pilar Negredo Patrycja Michalska Borja Hernndez‐García Cristina Snchez‐Ramos Juan A. Bernal Tsuneya Ikezu Rafael Len Manuela G. Lpez 《Journal of pineal research》2019,67(1)
Alterations in autophagy are increasingly being recognized in the pathogenesis of proteinopathies like Alzheimer's disease (AD). This study was conducted to evaluate whether melatonin treatment could provide beneficial effects in an Alzheimer model related to tauopathy by improving the autophagic flux and, thereby, prevent cognitive decline. The injection of AAV‐hTauP301L viral vectors and treatment/injection with okadaic acid were used to achieve mouse and human ex vivo, and in vivo tau‐related models. Melatonin (10 μmol/L) impeded oxidative stress, tau hyperphosphorylation, and cell death by restoring autophagy flux in the ex vivo models. In the in vivo studies, intracerebroventricular injection of AAV‐hTauP301L increased oxidative stress, neuroinflammation, and tau hyperphosphorylation in the hippocampus 7 days after the injection, without inducing cognitive impairment; however, when animals were maintained for 28 days, cognitive decline was apparent. Interestingly, late melatonin treatment (10 mg/kg), starting once the alterations mentioned above were established (from day 7 to day 28), reduced oxidative stress, neuroinflammation, tau hyperphosphorylation, and caspase‐3 activation; these observations correlated with restoration of the autophagy flux and memory improvement. This study highlights the importance of autophagic dysregulation in tauopathy and how administration of pharmacological doses of melatonin, once tauopathy is initiated, can restore the autophagy flux, reduce proteinopathy, and prevent cognitive decline. We therefore propose exogenous melatonin supplementation or the development of melatonin derivatives to improve autophagy flux for the treatment of proteinopathies like AD. 相似文献
6.
7.
8.
Anneloes Dirks Lucianne Groenink Koen G C Westphal Jocelien D A Olivier P Monika Verdouw Jan van der Gugten Mark A Geyer Berend Olivier 《Neuropsychopharmacology》2003,28(10):1790-1798
Chronically elevated levels of corticotropin-releasing factor (CRF) in transgenic mice overexpressing CRF in the brain (CRF-OE) appear to be associated with alterations commonly associated with major depressive disorder, as well as with sensorimotor gating deficits commonly associated with schizophrenia. In the present study, we tested the hypothesis that antipsychotics may be effective in normalizing prepulse inhibition (PPI) of acoustic startle in CRF-OE mice, which display impaired sensorimotor gating compared to wild-type (WT) mice. The typical antipsychotic haloperidol and atypical antipsychotic risperidone improved PPI in the CRF-OE mice, but were ineffective in WT mice. The atypical antipsychotic clozapine did not influence PPI in CRF-OE mice, but reduced gating in WT mice. This effect of clozapine in the CRF-OE mice may thus be regarded as a relative improvement, consistent with the observed effect of haloperidol and risperidone. As expected, the anxiolytic, nonantipsychotic chlordiazepoxide was devoid of any effect. All four compounds dose-dependently reduced the acoustic startle response irrespective of genotype. These results indicate that antipsychotic drugs are effective in improving startle gating deficits in the CRF-OE mice. Hence, the CRF-OE mouse model may represent an animal model for certain aspects of psychotic depression, and could be a valuable tool for research addressing the impact of chronically elevated levels of CRF on information processing. 相似文献
9.
10.
Claus D. Eisenbach Andreas Gldel Monika Terskan-Reinold Ulrich S. Schubert 《Macromolecular chemistry and physics.》1995,196(4):1077-1091
The synthesis and properties of segmented ABA triblock and (AB)n multiblock copolymer systems with 6,6′-disubstituted 2,2′-bipyridine (bpy) building blocks B and poly(oxytetramethylene) soft segments A are described. The access to the disubstituted bipyridines in large scale quantities was achieved by modification of conventional synthetic routes. In the presence of copper(I) ions these polymers formed mononuclear [Cu(I)(bpy)2] complexes in solution through self-assembly. The complexed copolymers were microphase separated systems in bulk with nano to mesoscopic superstructures consisting of copper-bpy complex aggregates in a polyether matrix. The thermal, mechanical and elastomer properties of the block copolymers varied with composition. 相似文献