全文获取类型
收费全文 | 4788篇 |
免费 | 266篇 |
国内免费 | 67篇 |
专业分类
耳鼻咽喉 | 82篇 |
儿科学 | 66篇 |
妇产科学 | 139篇 |
基础医学 | 342篇 |
口腔科学 | 300篇 |
临床医学 | 351篇 |
内科学 | 1319篇 |
皮肤病学 | 87篇 |
神经病学 | 453篇 |
特种医学 | 167篇 |
外科学 | 1027篇 |
综合类 | 20篇 |
一般理论 | 1篇 |
预防医学 | 171篇 |
眼科学 | 124篇 |
药学 | 192篇 |
中国医学 | 3篇 |
肿瘤学 | 277篇 |
出版年
2025年 | 3篇 |
2024年 | 44篇 |
2023年 | 75篇 |
2022年 | 119篇 |
2021年 | 211篇 |
2020年 | 130篇 |
2019年 | 169篇 |
2018年 | 197篇 |
2017年 | 130篇 |
2016年 | 177篇 |
2015年 | 212篇 |
2014年 | 255篇 |
2013年 | 254篇 |
2012年 | 405篇 |
2011年 | 442篇 |
2010年 | 254篇 |
2009年 | 227篇 |
2008年 | 337篇 |
2007年 | 325篇 |
2006年 | 306篇 |
2005年 | 271篇 |
2004年 | 230篇 |
2003年 | 145篇 |
2002年 | 121篇 |
2001年 | 14篇 |
2000年 | 7篇 |
1999年 | 8篇 |
1998年 | 10篇 |
1997年 | 9篇 |
1996年 | 9篇 |
1995年 | 6篇 |
1994年 | 6篇 |
1993年 | 3篇 |
1992年 | 1篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1984年 | 1篇 |
1980年 | 1篇 |
1976年 | 1篇 |
1972年 | 1篇 |
1962年 | 1篇 |
1893年 | 1篇 |
排序方式: 共有5121条查询结果,搜索用时 15 毫秒
991.
Georgios S. Papaetis Evgenia Anastasakou Dora Orphanidou 《European Journal of Internal Medicine》2009,20(6):579-585
Chlamydophila pneumoniae has been recognized as a common cause of respiratory tract infections affecting all age groups. The organism has been implicated as an infectious trigger for acute exacerbations of COPD. Moreover, the intracellular existence of this pathogen and the ability to cause chronic respiratory infections have led to a number of studies that investigated its possible association with disease development. The present paper examines and discusses the possible association of acute C. pneumoniae infection in episodes of acute exacerbation of COPD. It also reviews the existing evidence of chronic C. pneumoniae infection with disease pathogenesis and severity. The significant interstudy variation of the choice of diagnostic methods and criteria applied is most likely responsible for the great diversity of results observed. The use of well-standardized, commercially available diagnostic tools, as well as the adoption of a more unified diagnostic approach is probably the key element missing in order to clarify the exact role of C. pneumoniae in COPD. 相似文献
992.
993.
Carlos A. Molina MD PhD Andrew D. Barreto MD Georgios Tsivgoulis MD Paul Sierzenski MD Marc D. Malkoff MD Marta Rubiera MD Nicole Gonzales MD Robert Mikulik MD Greg Pate MA James Ostrem PhD Walter Singleton MD Garen Manvelian MD Evan C. Unger MD James C. Grotta MD Peter D. Schellinger MD PhD Andrei V. Alexandrov MD 《Annals of neurology》2009,66(1):28-38
994.
995.
996.
Sarrigiannis PG Randall M Kandler RH Grunewald RA Harkness K Reuber M 《Epilepsy & behavior : E&B》2011,20(3):450-453
The pathophysiology of stretch syncope is demonstrated through the clinical, electrophysiological, and hemodynamic findings in three patients. Fifty-seven attacks were captured by video/EEG monitoring. Simultaneous EEG, transcranial (middle cerebral artery) doppler, and continuous arterial pressure measurements were obtained for at least one typical attack of each patient. They all experienced a compulsion to precipitate their attacks. Episodes started with a stereotyped phase of stretching associated with neck torsion and breath holding, followed by a variable degree of loss of consciousness and asymmetric, recurrent facial and upper limb jerks in the more prolonged episodes. Significant sinus tachycardia coincided with the phase of stretching and was followed within 9-16 seconds by rhythmic generalized slow wave abnormalities on the EEG in attacks with impairment of consciousness. Transcranial doppler studies showed a dramatic drop in cerebral perfusion in the middle cerebral arteries during the episodes. The combination of the stereotyped semiology of the attacks, the pseudofocal myoclonic jerking, and the rhythmic generalized slow wave EEG abnormalities with the tachycardia make differential diagnosis from epilepsy challenging. 相似文献
997.
Korda Athanasia Zamaro Ewa Wagner Franca Morrison Miranda Caversaccio Marco Domenico Sauter Thomas C Schneider Erich Mantokoudis Georgios 《Journal of neurology》2022,269(3):1396-1403
Journal of Neurology - Skew deviation results from a dysfunction of the graviceptive pathways in patients with an acute vestibular syndrome (AVS) leading to vertical diplopia due to vertical ocular... 相似文献
998.
García-Borreguero D Kohnen R Högl B Ferini-Strambi L Hadjigeorgiou GM Hornyak M de Weerd AW Happe S Stiasny-Kolster K Gschliesser V Egatz R Cabrero B Frauscher B Trenkwalder C Hening WA Allen RP 《Sleep medicine》2007,8(5):455-463
BACKGROUND: Augmentation is the main complication during long-term dopaminergic treatment of restless legs syndrome (RLS) and reflects an overall increase in RLS severity. Its severity varies considerably from a minor problem to a devastating exacerbation of disease. Despite its clinical relevance, systematic evaluations have rarely been undertaken and there has been no development of methods to assess the severity of augmentation. To fill this gap, the European RLS Study Group (EURLSSG) has developed the Augmentation Severity Rating Scale (ASRS), using three items that assess the degree of change in three specific dimensions of augmentation. The changes in each dimension are summed to give an ASRS total score. METHODS: The ASRS was developed to cover the basic dimensions defining RLS augmentation. The items were developed by an interactive process involving professional and patient input. The ASRS that was evaluated included four major items and two alternative forms of one item. The validation was conducted using 63 (85%) mostly untreated RLS patients from six centers, who were treated for six months with levodopa (L-Dopa) (up to 500 mg/day, as clinically needed). Two consecutive assessments before and at baseline measured test-retest reliability. Consecutive ASRS ratings by two independent raters on a subsample of patients evaluated inter-rater reliability. Comparison with clinical severity ratings of two independent experts provided external validation of the ASRS. Comparison of patients with and without augmentation with regard to the items and the total score of the ASRS added discriminant validity. RESULTS: Sixty patients (63% females, mean age: 53 years, baseline International RLS Severity Rating (IRLS) score 24.7+/-5.2) were treated with a median daily dose of 300 mg L-Dopa (range: 50-500 mg). Thirty-six patients (60%) experienced augmentation. Item analyses indicated that one item could be removed as it did not contribute significantly to the test score and only one form of the duplicated item needed to be used. The final ASRS then included three items. Test-retest reliability for the total score was rho=0.72, and inter-rater reliability was rcc=0.94. Cronbach's alpha was 0.62. Validity as assessed by the correlation between the worst ASRS total score during the trial and the expert rating was rho=0.72. ASRS total score differed between patients without versus with augmentation (mean: 7.4 (standard deviation (SD)=4.0) vs. 2.0 (2.7) (P<0.0001). CONCLUSIONS: The ASRS is a reliable and valid scale to measure the severity of augmentation. Due to the need to systematically quantify augmentation for both long-term efficacy and tolerability, the ASRS may become a useful tool to monitor augmentation in future clinical trials. 相似文献
999.
Association between the plasminogen activator inhibitor-1 4G/5G polymorphism and venous thrombosis. A meta-analysis 总被引:3,自引:0,他引:3
Tsantes AE Nikolopoulos GK Bagos PG Rapti E Mantzios G Kapsimali V Travlou A 《Thrombosis and haemostasis》2007,97(6):907-913
The effect of the 675 insertion/deletion (4G/5G) polymorphism of plasminogen activator inhibitor-1 (PAI-1) gene on the risk of venous thromboembolism (VTE) remains controversial. In this study, we performed a meta-analysis of published data regarding this issue. A comprehensive electronic search was carried out up until September 2006. A total of 22 articles were included in the analysis that was performed using random effects models. Eighteen papers, concerning patients without another known risk factor, comprised 2,644 cases and 3,739 controls. The alleles contrast (4G vs. 5G allele) yielded a statistically significant odds ratio (OR) of 1.153 (95% confidence interval [CI]: 1.068-1.246). In a sub-analysis of five studies that included 256 cases with another genetic risk factor and 147 controls, the combined per-allele OR was still significant (OR: 1.833,95% CI: 1.325-2.536). On the contrary, the analysis of five studies regarding cases with a non-genetic risk factor for VTE (antiphospholipid antibody syndrome, Behcet disease) provided insignificant results in all aspects. There was no evidence for heterogeneity and publication bias in all analyses. Based on our findings, the 4G allele appears to increase the risk of venous thrombosis, particularly in subjects with other genetic thrombophilic defects. Recommendation for detection of this polymorphism in evaluating thrombophilia in such patients might be considered. 相似文献