全文获取类型
收费全文 | 7369篇 |
免费 | 608篇 |
国内免费 | 12篇 |
专业分类
耳鼻咽喉 | 85篇 |
儿科学 | 252篇 |
妇产科学 | 196篇 |
基础医学 | 1012篇 |
口腔科学 | 142篇 |
临床医学 | 885篇 |
内科学 | 1393篇 |
皮肤病学 | 141篇 |
神经病学 | 758篇 |
特种医学 | 179篇 |
外科学 | 925篇 |
综合类 | 105篇 |
一般理论 | 6篇 |
预防医学 | 825篇 |
眼科学 | 233篇 |
药学 | 411篇 |
中国医学 | 3篇 |
肿瘤学 | 438篇 |
出版年
2024年 | 25篇 |
2023年 | 144篇 |
2022年 | 202篇 |
2021年 | 451篇 |
2020年 | 269篇 |
2019年 | 367篇 |
2018年 | 344篇 |
2017年 | 273篇 |
2016年 | 303篇 |
2015年 | 267篇 |
2014年 | 332篇 |
2013年 | 392篇 |
2012年 | 517篇 |
2011年 | 534篇 |
2010年 | 258篇 |
2009年 | 222篇 |
2008年 | 360篇 |
2007年 | 306篇 |
2006年 | 295篇 |
2005年 | 265篇 |
2004年 | 236篇 |
2003年 | 257篇 |
2002年 | 203篇 |
2001年 | 80篇 |
2000年 | 51篇 |
1999年 | 54篇 |
1998年 | 36篇 |
1997年 | 23篇 |
1996年 | 23篇 |
1995年 | 26篇 |
1994年 | 21篇 |
1992年 | 42篇 |
1991年 | 33篇 |
1990年 | 43篇 |
1989年 | 36篇 |
1988年 | 46篇 |
1987年 | 53篇 |
1986年 | 41篇 |
1985年 | 35篇 |
1984年 | 41篇 |
1983年 | 34篇 |
1982年 | 21篇 |
1979年 | 25篇 |
1978年 | 29篇 |
1977年 | 28篇 |
1975年 | 22篇 |
1974年 | 27篇 |
1973年 | 24篇 |
1972年 | 31篇 |
1968年 | 22篇 |
排序方式: 共有7989条查询结果,搜索用时 0 毫秒
1.
2.
Improvement in Tricuspid Annular Plane Systolic Excursion with Pulmonary Hypertension Therapy in Pediatric Patients
下载免费PDF全文
![点击此处可从《Echocardiography (Mount Kisco, N.Y.)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
3.
4.
Few studies have examined the effects of parental incarceration (PI) on outcomes above and beyond other risk and adverse childhood experiences (ACEs). The objectives of this study were to (1) the associations between PI and mental health problems (attention, externalizing, internalizing, and total behavioral problems) and (2) the mediating role of current socioeconomic status and cumulative ACEs. An observational and cross-sectional design was employed. Analyses included hierarchical multivariable linear regression modeling. The analytic sample included 613 adolescents (11–17?years). On average, youth exposed to PI experienced three times as many ACEs compared with youth unexposed. Youth exposed to PI were more likely to have behavioral problems than their unexposed peers. The main effect for all models was attenuated by current economic hardship as well as exposure to increasing numbers of ACEs. Exposure to PI can be viewed as a marker of accumulative risk for intervention since youth impacted by PI are more likely to experience behavioral difficulties and associated adverse childhood experiences. Due to the associated adversity that impact youth exposed to PI, mental health providers need to be able to identify and screen for symptoms associated with trauma. 相似文献
5.
6.
7.
8.
9.
10.
Paramecium calcium channels are blocked by a family of calmodulin antagonists. 总被引:3,自引:0,他引:3
下载免费PDF全文
![点击此处可从《Proceedings of the National Academy of Sciences of the United States of America》网站下载免费的PDF全文](/ch/ext_images/free.gif)
B E Ehrlich A R Jacobson R Hinrichsen L M Sayre M A Forte 《Proceedings of the National Academy of Sciences of the United States of America》1988,85(15):5718-5722
Although the voltage-sensitive Ca channel present in Paramecium has been subjected to detailed physiological and genetic analysis, no organic ligands have been described that block this channel with high affinity and that ultimately can be used to identify channel components. Based on a previous observation that the naphthalene sulfonamide calmodulin antagonist W-7 can block Paramecium Ca channels at high concentration, we have synthesized analogs of W-7 that block these channels at concentrations of less than 1 microM. The effectiveness of these compounds was tested both by a sensitive behavioral assay and on Ca channels that had been incorporated into planar lipid bilayers. Despite the fact that these compounds are effective Paramecium calmodulin antagonists, two independent lines of evidence suggest that W-7 and its analogs block the Ca channel by a mechanism that is independent of their action on calmodulin. In addition, the sensitivity to W-7 or dihydropyridines of Ca channels present in a number of eukaryotic phyla has been used to identify similarities in Ca channels from widely diverse organisms. It appears that the pharmacological specificity provides a means to group Ca channels. 相似文献