全文获取类型
收费全文 | 180931篇 |
免费 | 10430篇 |
国内免费 | 796篇 |
专业分类
耳鼻咽喉 | 1937篇 |
儿科学 | 5122篇 |
妇产科学 | 4027篇 |
基础医学 | 25391篇 |
口腔科学 | 6546篇 |
临床医学 | 15477篇 |
内科学 | 42287篇 |
皮肤病学 | 4385篇 |
神经病学 | 17102篇 |
特种医学 | 4315篇 |
外国民族医学 | 1篇 |
外科学 | 19525篇 |
综合类 | 739篇 |
一般理论 | 78篇 |
预防医学 | 17051篇 |
眼科学 | 3105篇 |
药学 | 12586篇 |
中国医学 | 676篇 |
肿瘤学 | 11807篇 |
出版年
2024年 | 123篇 |
2023年 | 1402篇 |
2022年 | 2385篇 |
2021年 | 4779篇 |
2020年 | 2954篇 |
2019年 | 4294篇 |
2018年 | 5740篇 |
2017年 | 4088篇 |
2016年 | 4584篇 |
2015年 | 5408篇 |
2014年 | 6546篇 |
2013年 | 8807篇 |
2012年 | 15323篇 |
2011年 | 15860篇 |
2010年 | 8014篇 |
2009年 | 6452篇 |
2008年 | 12971篇 |
2007年 | 13143篇 |
2006年 | 12523篇 |
2005年 | 11925篇 |
2004年 | 10752篇 |
2003年 | 9789篇 |
2002年 | 9004篇 |
2001年 | 2161篇 |
2000年 | 2490篇 |
1999年 | 1653篇 |
1998年 | 1051篇 |
1997年 | 839篇 |
1996年 | 744篇 |
1995年 | 629篇 |
1994年 | 570篇 |
1993年 | 480篇 |
1992年 | 433篇 |
1991年 | 325篇 |
1990年 | 278篇 |
1989年 | 277篇 |
1988年 | 237篇 |
1987年 | 206篇 |
1986年 | 234篇 |
1985年 | 193篇 |
1984年 | 247篇 |
1983年 | 203篇 |
1982年 | 252篇 |
1981年 | 198篇 |
1980年 | 211篇 |
1979年 | 119篇 |
1978年 | 122篇 |
1977年 | 110篇 |
1976年 | 95篇 |
1974年 | 96篇 |
排序方式: 共有10000条查询结果,搜索用时 234 毫秒
101.
102.
H N David M Dhilly M Degoulet G Poisnel C Meckler N Vallée J-é Blatteau J-J Risso M Lemaire D Debruyne J H Abraini 《Translational psychiatry》2015,5(7):e594
We investigated the effects of the noble gas argon on the expression of locomotor sensitization to amphetamine and amphetamine-induced changes in dopamine release and mu-opioid neurotransmission in the nucleus accumbens. We found (1) argon blocked the increase in carrier-mediated dopamine release induced by amphetamine in brain slices, but, in contrast, potentiated the decrease in KCl-evoked dopamine release induced by amphetamine, thereby suggesting that argon inhibited the vesicular monoamine transporter-2; (2) argon blocked the expression of locomotor and mu-opioid neurotransmission sensitization induced by repeated amphetamine administration in a short-term model of sensitization in rats; (3) argon decreased the maximal number of binding sites and increased the dissociation constant of mu-receptors in membrane preparations, thereby indicating that argon is a mu-receptor antagonist; (4) argon blocked the expression of locomotor sensitization and context-dependent locomotor activity induced by repeated administration of amphetamine in a long-term model of sensitization. Taken together, these data indicate that argon could be of potential interest for treating drug addiction and dependence. 相似文献
103.
José Roberto Jurado Jorge Hernán Santos Nieto Jairo Ospina Gaitán Constanza Garzón Bonilla Ricardo Villarreal David Acevedo Laura Cabrera Luis Felipe Cabrera Mauricio Pedraza 《Arab Journal Of Gastroenterology》2021,22(2):170-173
Background and study aimsThe COVID-19 outbreak has reorganized surgical team conditions regarding endoscopy. The number of interventions has been reduced, the number of healthcare professionals must be limited, and both the patients and physicians are more protected than ever.Patients and MethodsIn the highest peak of contagion in Colombia, endoscopy, colonoscopy, and esophagogastroduodenoscopy were performed using a low-cost disposable device. A total of 1388 procedures were performed. Every patient was assessed for symptoms via a telephone call, at the health center, and after the procedure, following specific attention routes.ResultsAfter procedure follow-up, no positive cases of COVID-19 were noted.ConclusionThe methodology reduced the risk of infection during the COVID-19 pandemic. 相似文献
104.
Paolo Mazzone Fabrizio Stocchi Salvatore Galati Angelo Insola Maria Grazia Altibrandi Nicola Modugno Domenicantonio Tropepi Livia Brusa Alessandro Stefani 《Neuromodulation》2006,9(3):221-228
Objectives. Traditional deep brain stimulation (DBS) at the subthalamic nucleus (STN) has proved to be efficacious on core Parkinsonian symptoms. However, very disabling l ‐dopa–induced abnormal involuntary movements (AIMs) and axial signs are slightly affected, suggesting that we target less conventional targets. Our candidates for DBS were the globus pallidus internus (GPi) plus the intralaminar thalamic complex (Pf or CM), given its extensive functional links with basal ganglia nuclei. Materials and Methods. The routine utilization of our innovative stereotactic apparatus allows us to implant, at the same time, both the CM‐Pf complex together with the GPi in six Parkinson disease patients. Both intraoperative and postoperative neurophysiologic assessments helped us recognize functional subregions while optimizing implantation of electrodes. Unified Parkinson disease rating scale (UPDRS) motor scores, AIMs, and freezing were carefully blindly evaluated for each condition. Results. A significant amelioration of UPDRS scores was achieved by simultaneous activation of both targets. CM‐Pf activation was only slightly effective in reducing rigidity and akinesia, but more efficacious on freezing. Not surprisingly, AIMs were peculiarly decreased by the activation of the permanent electro‐catheter in the posteroventral GPi. Conclusions. These findings confirm that, in selected patients, it is conceivable to target structures other than the conventional STN in order to maximize clinical benefit. 相似文献
105.
106.
Zinc sulfate addition to glass-ionomer-based cements: influence on physical and antibacterial properties, zinc and fluoride release. 总被引:5,自引:0,他引:5
Prudencio W R Osinaga Rosa Helena M Grande Rafael Y Ballester Maria Regina L Simionato Célia Regina M Delgado Rodrigues Antonio Muench 《Dental materials》2003,19(3):212-217
OBJECTIVES: The aim of this study is to evaluate the effect of ZnSO(4) addition to a conventional glass ionomer and a resin-modified glass ionomer on solubility, flexural strength, zinc and fluoride (F) release, and Streptococcus mutans growth inhibition. METHODS: 5 or 10% ZnSO(4) was added to Vitremer and Ketac-Fil powders. Solubility test was performed based on ISO 7489. Flexural strength was determined by 3-point bending test based on ISO 4049. Zn release/uptake was determined by atomic emission spectrometry; F release/uptake was measured using a F-specific electrode. Both release measurements were performed for 15 d before and 15 d after recharging. Antibacterial test was conducted according to agar plate methods against S. mutans, by measuring the inhibition halos in 1-h and 15-d specimens. Data were analyzed by ANOVA. RESULTS: Solubility increased with higher ZnSO(4) content, but remained below the ISO 7489 limit. Flexural strength was not affected by ZnSO(4) addition, and Vitremer performed better than Ketac-Fil. The control materials released no zinc. Vitremer with 10% ZnSO(4) released the highest amount of zinc. Fluoride release was similar for Ketac-Fil and Vitremer. In both cases, the highest amounts were released in the first 24 h. The growth inhibition halo of S. mutans was similar for both materials with highest content of ZnSO(4) and occurred only with 1-h specimens. SIGNIFICANCE: Zinc addition decreased microorganisms growth and improved fluoride release, without significantly affecting the materials' flexural strength and solubility. 相似文献
107.
108.
109.
110.
Access to good-quality health services is crucial for the improvement of many health outcomes, such as those targeted by the
Millennium Development Goals (MDGs) adopted by the international community in 2000. The health-related MDGs cannot be achieved
if vulnerable populations do not have access to skilled personnel and to other necessary inputs. This paper focuses on the
geographical dimension of access and on one of its critical determinants: the availability of qualified personnel. The objective
of this paper is to offer a better understanding of the determinants of geographical imbalances in the distribution of health
personnel, and to identify and assess the strategies developed to correct them. It reviews the recent literature on determinants,
barriers and the effects of strategies that attempted to correct geographical imbalances, with a focus on empirical studies
from developing and developed countries. An analysis of determinants of success and failures of strategies implemented, and
a summary of lessons learnt, is included. 相似文献