全文获取类型
收费全文 | 13488篇 |
免费 | 1802篇 |
国内免费 | 51篇 |
专业分类
耳鼻咽喉 | 207篇 |
儿科学 | 399篇 |
妇产科学 | 246篇 |
基础医学 | 2214篇 |
口腔科学 | 282篇 |
临床医学 | 1574篇 |
内科学 | 2723篇 |
皮肤病学 | 217篇 |
神经病学 | 1026篇 |
特种医学 | 716篇 |
外国民族医学 | 1篇 |
外科学 | 1641篇 |
综合类 | 639篇 |
一般理论 | 8篇 |
预防医学 | 1508篇 |
眼科学 | 196篇 |
药学 | 1010篇 |
中国医学 | 27篇 |
肿瘤学 | 707篇 |
出版年
2021年 | 135篇 |
2020年 | 116篇 |
2019年 | 187篇 |
2018年 | 255篇 |
2017年 | 174篇 |
2016年 | 160篇 |
2015年 | 204篇 |
2014年 | 255篇 |
2013年 | 429篇 |
2012年 | 577篇 |
2011年 | 570篇 |
2010年 | 329篇 |
2009年 | 295篇 |
2008年 | 495篇 |
2007年 | 508篇 |
2006年 | 506篇 |
2005年 | 474篇 |
2004年 | 483篇 |
2003年 | 471篇 |
2002年 | 431篇 |
2001年 | 418篇 |
2000年 | 479篇 |
1999年 | 404篇 |
1998年 | 269篇 |
1997年 | 215篇 |
1996年 | 245篇 |
1995年 | 213篇 |
1994年 | 210篇 |
1993年 | 190篇 |
1992年 | 324篇 |
1991年 | 338篇 |
1990年 | 297篇 |
1989年 | 359篇 |
1988年 | 295篇 |
1987年 | 311篇 |
1986年 | 285篇 |
1985年 | 275篇 |
1984年 | 275篇 |
1983年 | 211篇 |
1982年 | 187篇 |
1981年 | 140篇 |
1980年 | 126篇 |
1979年 | 198篇 |
1978年 | 151篇 |
1977年 | 150篇 |
1976年 | 138篇 |
1975年 | 105篇 |
1974年 | 110篇 |
1973年 | 100篇 |
1972年 | 104篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
2.
Xiumei Jiang Xiaowei Zhang Patrick Gray Jiwen Zheng Timothy R. Croley Peter P. Fu 《journal of environmental science and health part c-environmental carcinogenesis & ecotoxicology reviews》2019,37(2):116-131
Gold nanoparticles (Au NPs) hold great promise in food, industrial and biomedical applications due to their unique physicochemical properties. However, influences of the gastrointestinal tract (GIT), a likely route for Au NPs administration, on the physicochemical properties of Au NPs has been rarely evaluated. Here, we investigated the influence of GIT fluids on the physicochemical properties of Au NPs (5, 50, and 100?nm) and their implications on intestinal epithelial permeability in vitro. Au NPs aggregated in fasted gastric fluids and generated hydroxyl radicals in the presence of H2O2. Cell studies showed that GIT fluids incubation of Au NPs affected the cellular uptake of Au NPs but did not induce cytotoxicity or disturb the intestinal epithelial permeability. 相似文献
3.
Erin C. Tully Jackson M. Gray Sherryl H. Goodman Stephen Nowicki Jr. 《Early child development and care》2016,186(12):1939-1951
Children who expect they can bring about good outcomes and avoid bad outcomes tend to experience more personal successes. Little is known about factors that contribute to these ‘control expectancies’. The purpose of the present study was to determine whether children's internal control expectancies occur in the context of parents’ internal control expectancies, low family strain, and high family cohesiveness and whether these factors are more strongly related to daughters’ than sons’ control expectancies. A community sample of 85 children aged 9–11 years and their parents (85 mothers; 63 fathers) completed rating scales. Fathers’ more internal control expectancies and mothers’ reports of fewer family strains were associated with daughters’ but not sons’ greater internal control expectancies, and greater family cohesiveness was related to both daughters’ and sons’ internal control orientations. These findings suggest that family factors may contribute to children's, particularly daughters’, development of internal control expectancies. 相似文献
4.
5.
Fluid role boundaries: exploring the contribution of the advanced nurse practitioner to multi‐professional palliative care
下载免费PDF全文
![点击此处可从《Journal of clinical nursing》网站下载免费的PDF全文](/ch/ext_images/free.gif)
6.
Jennifer B. Gray Neal D. Gray 《International journal of mental health and addiction》2006,4(4):307-318
Some researchers speculate that as many as 10% of users worldwide suffer from “problematic” use of the internet, possibly stemming from an internet dependency. Research is in its early stages, making it an uncertain issue for mental health professionals. This paper provides: (1) a critical review of research on problematic internet use for the mental health and addictions professional; and (2) practical implications, including suggestions on treatment and prevention, given its uncertain clinical classification. 相似文献
7.
MATTHEW B. COLLIER C. ANDERSON ENGH JR. JAMES P. MCAULEY STUART D. GINN GERARD A. ENGH 蔡迅梓 《骨科动态》2006,2(2):93-99
背景:从关节和胫骨假体聚乙烯衬垫后表面转移磨损碎屑,是全膝关节置换术后假体周围骨溶解的主要原因。全膝人工关节假体设计随时问而发生变化,例如对胫骨盘近端表面的粗糙度和聚乙烯衬垫的灭菌方法。我们假设胫骨盘表面抛光和采用空气中γ射线照射之外的其他方法对衬垫灭菌,可降低骨溶解的发生率。方法:从1987年至1998年,我们采用后十字韧带保留型的解剖型组配式全膝人工关节假体系列。对300名患者施行365例全膝关节置换术。术后5至10年,对这些患者的膝关节摄正、侧位X线片。由两位关节置换专家对X线片上的骨溶解状况进行单独评定(骨溶解的界定标准为假体周围存在边缘清晰的非线性松质骨丢失区)。结果:在粗糙表面的胫骨盘的242例膝关节中,使用空气中γ射线照射灭菌的衬垫固定,有34%(82例)骨溶解阳性。用惰性气体中γ射线照射或没有照射的衬垫与抛光表面连接的98例膝关节中,有9%(9例)骨溶解阳性。骨溶解与六项因素相关,这些因素为:一项与患者(男性)相关、一项与胫骨盘(近端表面抛光)相关、三项与聚乙烯衬垫(加工的原材料、灭菌方法及存放时间)相关及一项与手术技术(股骨假体与胫骨假体间的过伸)相关。结论:在这类假体设计中,胫骨盘近端表面采用抛光及衬垫采用更为先进的灭菌方法(不用空气中γ射线照射灭菌)能显著减少骨溶解的发生率,但不能避免骨溶解。 相似文献
8.
Veena Kumari Jeffrey A. Gray Philip J. Corr Owen F. Mulligan Paul A. Cotter Stuart A. Checkley 《Psychopharmacology》1997,129(3):271-276
The effects of an indirect dopamine-agonist, d-amphetamine, and a non-selective dopamine receptor antagonist, haloperidol, were investigated in normal male volunteers using
a between-subjects double-blind design in a procedural learning task, thought mainly to involve unconscious/automatic learning.
The results showed: (1) d-amphetamine facilitated response speed, whereas haloperidol inhibited it, in comparison to placebo; (2) the linear increase
in procedural learning corresponded with pharmacological manipulation of degree of dopaminergic activity, i.e. subjects given
haloperidol showed the least, and subjects given d-amphetamine the greatest, procedural learning. The implications of these findings are discussed in relation to investigation
of abnormalities of procedural learning processes in schizophrenia.
Received: 28 June 1996/Final version: 2 October 1996 相似文献
9.
By injecting small amounts of CO2 through a needle, one can move bowel or bladder from the intended path of instruments during interventional procedures. The technique worked well in six of seven cases in the pelvis and retroperitoneum; it was not effective in the mediastinum or midabdomen (n = 6). 相似文献
10.