全文获取类型
收费全文 | 1774篇 |
免费 | 307篇 |
国内免费 | 8篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 58篇 |
妇产科学 | 281篇 |
基础医学 | 79篇 |
口腔科学 | 27篇 |
临床医学 | 852篇 |
内科学 | 168篇 |
皮肤病学 | 51篇 |
神经病学 | 21篇 |
特种医学 | 236篇 |
外科学 | 49篇 |
综合类 | 56篇 |
预防医学 | 87篇 |
眼科学 | 5篇 |
药学 | 65篇 |
肿瘤学 | 52篇 |
出版年
2024年 | 4篇 |
2023年 | 43篇 |
2022年 | 5篇 |
2021年 | 7篇 |
2020年 | 34篇 |
2019年 | 18篇 |
2018年 | 57篇 |
2017年 | 92篇 |
2016年 | 76篇 |
2015年 | 99篇 |
2014年 | 102篇 |
2013年 | 98篇 |
2012年 | 37篇 |
2011年 | 61篇 |
2010年 | 102篇 |
2009年 | 100篇 |
2008年 | 42篇 |
2007年 | 47篇 |
2006年 | 42篇 |
2005年 | 22篇 |
2004年 | 16篇 |
2003年 | 31篇 |
2002年 | 23篇 |
2001年 | 37篇 |
2000年 | 10篇 |
1999年 | 47篇 |
1998年 | 93篇 |
1997年 | 109篇 |
1996年 | 105篇 |
1995年 | 93篇 |
1994年 | 64篇 |
1993年 | 48篇 |
1992年 | 21篇 |
1991年 | 23篇 |
1990年 | 10篇 |
1989年 | 32篇 |
1988年 | 31篇 |
1987年 | 18篇 |
1986年 | 26篇 |
1985年 | 29篇 |
1984年 | 13篇 |
1983年 | 13篇 |
1982年 | 18篇 |
1981年 | 12篇 |
1980年 | 15篇 |
1979年 | 4篇 |
1978年 | 16篇 |
1977年 | 15篇 |
1976年 | 13篇 |
1975年 | 13篇 |
排序方式: 共有2089条查询结果,搜索用时 14 毫秒
1.
2.
M J Barbanoj R M Antonijoan J Riba M Valle S Romero F Jané 《Clinical EEG and neuroscience》2006,37(2):108-120
A drug interaction refers to an event in which the usual pharmacological effect of a drug is modified by other factors, most frequently additional drugs. When two drugs are administered simultaneously, or within a short time of each other, an interaction can occur that may increase or decrease the intended magnitude or duration of the effect of one or both drugs. Drugs may interact on a pharmaceutical, pharmacokinetic or pharmacodynamic basis. Pharmacodynamic interactions arise when the alteration of the effects occurs at the site of action. This is a wide field where not only interactions between different drugs are considered but also drug and metabolites (midazolam/alpha-hydroxy-midazolam), enantiomers (ketamine), as well as phenomena such as tolerance (nordiazepam) and sensitization (diazepam). Pharmacodynamic interactions can result in antagonism or synergism and can originate at a receptor level (antagonism, partial agonism, down-regulation, up-regulation), at an intraneuronal level (transduction, uptake), or at an interneuronal level (physiological pathways). Alternatively, psychotropic drug interactions assessed through quantitative pharmaco-EEG can be viewed according to the broad underlying objective of the study: safety-oriented (ketoprofen/theophylline, lorazepam/diphenhydramine, granisetron/haloperidol), strictly pharmacologically-oriented (benzodiazepine receptors), or broadly neuro-physiologically-oriented (diazepam/buspirone). Methodological issues are stressed, particularly drug plasma concentrations, dose-response relationships and time-course of effects (fluoxetine/buspirone), and unsolved questions are addressed (yohimbine/caffeine, hydroxizyne/alcohol). 相似文献
3.
D Van Neste† RM Trüeb‡ 《Journal of the European Academy of Dermatology and Venereology》2006,20(5):578-583
BACKGROUND: Computer-assisted image analysis has been proposed for human hair growth studies. METHODS: The performances of Trichoscan, a commercially available automated system combining epiluminiscence microscopy with digital image analysis, developed for office-based hair growth measurements, have been evaluated comparatively on the same skin sites using standardized photographic equipment and calibrated processing for contrast-enhanced phototrichogram (CE-PTG) analysis. This reference method has been validated with scalp biopsies and histological examination of serial sectioning. RESULTS: Besides edge effects, hair fibres escaped the Trichoscan analysis for various reasons including, but not limited to, thickness, pigmentation, closeness and crossing. CONCLUSION: Most of these problems have been identified in the late 1980s and remain largely unsolved by the processing software that was evaluated in 2004. Therefore claims promoting the Trichoscan method for accurate hair measurements in clinical trials on scalp and body hair are not supported by the present investigation. The speed at which the analysis is performed is outweighed by the errors in signal detection. Therefore we suggest that improvements must be clearly documented before Trichoscan is established for quantified diagnostic purposes and detailed hair cycle monitoring during hair trials. 相似文献
4.
5.
V Schleyer† S Radakovic-Fijan‡ S Karrer† T Zwingers§ A Tanew‡ M Landthaler† RM Szeimies† 《Journal of the European Academy of Dermatology and Venereology》2006,20(7):823-828
BACKGROUND: Based on good results in the treatment of superficial skin tumours, since the early 1990s topical photodynamic therapy with aminolaevulinic acid (ALA PDT) has been used for disseminated, inflammatory dermatoses including psoriasis. However, there is still a lack of well-documented trials. OBJECTIVE: A prospective randomized, double-blind phase I/II intrapatient comparison study was conducted in 12 patients to investigate whether topical ALA PDT is an effective treatment for chronic plaque-type psoriasis. METHODS: In each patient three psoriatic plaques were randomly treated with a light dose of 20 J/cm(2) and 0.1%, 1% and 5% ALA, respectively. Treatment was conducted twice a week until complete clearance or for a maximum of 12 irradiations. Therapeutic efficacy was assessed by weekly determination of the psoriasis severity index (PSI). RESULTS: The mean percentage improvement was 37.5%, 45.6% and 51.2% in the 0.1%, 1% and 5% ALA-treated groups, respectively. Irradiation had to be interrupted several times because of severe burning and pain sensation. CONCLUSION: Topical ALA PDT did not prove to be an appropriate treatment option for plaque-type psoriasis due to disappointing clinical efficacy, the time-consuming treatment procedure and its unfavourable adverse event profile. 相似文献
6.
7.
8.
9.
M.M. Bialoskurski MA RN RM C.L. Cox MSc PhD RN & R.D. Wiggins PhD 《Journal of advanced nursing》2002,37(1):62-69
AIM: The aim of this study was to investigate the nature and organization of maternal needs and priorities in a neonatal unit. BACKGROUND: The relationship between maternal needs and priorities appears to be an under studied area in neonatal nursing. METHODS: A quantitative survey was carried out based on 209 mothers with premature infants. Two self-assessment schedules were used: critical care maternal needs inventory (J. Leske, Heart and Lung 15, 27-42) and a ranking scale. The data were analysed with multivariate analysis. FINDINGS: Data analysis revealed clear priorities in maternal needs. In particular the need for accurate infant related information was a priority for 93% of the mothers. Good communication practices with professionals were also valued. The mothers displayed altruistic behaviour, and self-related needs took second place. It is proposed that maternal needs demonstrate a hierarchical organization. CONCLUSION: It is important for nurses to consider the individual needs of the mothers, simply because the satisfaction of these needs is essential for maternal well-being. 相似文献
10.