全文获取类型
收费全文 | 6029篇 |
免费 | 612篇 |
国内免费 | 12篇 |
专业分类
耳鼻咽喉 | 24篇 |
儿科学 | 128篇 |
妇产科学 | 90篇 |
基础医学 | 851篇 |
口腔科学 | 93篇 |
临床医学 | 894篇 |
内科学 | 1160篇 |
皮肤病学 | 79篇 |
神经病学 | 618篇 |
特种医学 | 183篇 |
外科学 | 775篇 |
综合类 | 115篇 |
一般理论 | 8篇 |
预防医学 | 713篇 |
眼科学 | 91篇 |
药学 | 505篇 |
中国医学 | 5篇 |
肿瘤学 | 321篇 |
出版年
2023年 | 45篇 |
2022年 | 49篇 |
2021年 | 129篇 |
2020年 | 97篇 |
2019年 | 132篇 |
2018年 | 160篇 |
2017年 | 112篇 |
2016年 | 118篇 |
2015年 | 113篇 |
2014年 | 146篇 |
2013年 | 233篇 |
2012年 | 418篇 |
2011年 | 406篇 |
2010年 | 223篇 |
2009年 | 212篇 |
2008年 | 423篇 |
2007年 | 344篇 |
2006年 | 375篇 |
2005年 | 340篇 |
2004年 | 285篇 |
2003年 | 257篇 |
2002年 | 254篇 |
2001年 | 107篇 |
2000年 | 124篇 |
1999年 | 107篇 |
1998年 | 59篇 |
1997年 | 52篇 |
1996年 | 45篇 |
1995年 | 33篇 |
1994年 | 26篇 |
1993年 | 36篇 |
1992年 | 93篇 |
1991年 | 80篇 |
1990年 | 77篇 |
1989年 | 78篇 |
1988年 | 82篇 |
1987年 | 73篇 |
1986年 | 55篇 |
1985年 | 60篇 |
1984年 | 46篇 |
1983年 | 45篇 |
1982年 | 28篇 |
1981年 | 23篇 |
1980年 | 24篇 |
1979年 | 31篇 |
1978年 | 22篇 |
1976年 | 25篇 |
1974年 | 25篇 |
1972年 | 22篇 |
1931年 | 19篇 |
排序方式: 共有6653条查询结果,搜索用时 8 毫秒
1.
Stuart J. Dilley Tracey J. Weiland Robert O’Brien Neil J. Cunningham Julian E. Van Dijk Rosie M. Mahoney 《Teaching and learning in medicine》2015,27(1):71-79
Theory: Immersive simulation is a common mode of education for medical students. Observation of clinical simulations prior to participation is believed to be beneficial, though this is often a passive process. Active observation may be more beneficial. Hypotheses: The hypothesis tested in this study was that the active use of a simple checklist during observation of an immersive simulation would result in better participant performance in a subsequent scenario compared with passive observation alone. Methods: Medical students were randomized to either passive or active (with checklist) observation of an immersive simulation involving cardiac arrest prior to participating in their own simulation. Performance measures included time to cardiopulmonary resuscitation (CPR) and time to defibrillation and were compared between first and second scenarios as well as between passive and active observers. Results: Seventy-nine simulations involving 232 students were conducted. Mean time to CPR was 18 seconds (SD = 11.6) for those using the checklist and 24 seconds (SD = 15.8) for those who observed passively (M difference = 6 seconds), t(35) = 1.46, p =.153. Time to defibrillation was 94 seconds (SD = 26.4) for those using the checklist and 92 seconds (SD = 23.8) for those who observed passively (M difference = –2 seconds), t(38) =.21, p =.837. Time to CPR was 24 seconds (SD = 15.8) for passive observers and 31 seconds (SD = 21.0; M difference = 7 seconds), t(35) = 1.13, p =.265, for their first scenario counterparts. Time to CPR was 18 seconds (SD = 11.6) for active observers and 36 seconds (SD = 26.2; M difference = 18 seconds), t(24) = 2.81, p =.010, for their first scenario counterparts. Time to defibrillation was 92 seconds (SD = 23.8) for passive observers and 125 seconds (SD = 32.2; M difference = 33 seconds), t(33) = 3.63, p =.001, for their first scenario counterparts. Time to defibrillation was 94 seconds (SD = 26.4) for the active observers and 132 seconds (SD = 52.9; M difference = 38 seconds), t(28) =.46, p =.008, for their first scenario counterparts. Conclusions: Observation alone leads to improved performance in the management of a simulated cardiac arrest. The active use of a simple skills-based checklist during observation did not appear to improve performance over passive observation alone. 相似文献
2.
3.
4.
R J Elwood P J Hildebrand J W Dundee P S Collier 《British journal of clinical pharmacology》1983,15(6):743-745
In a randomised crossover study in volunteers plasma midazolam levels were estimated for 24 h following 15 mg by mouth, either preceded by no medication or following 24 h therapy with ranitidine. Administration of the H2-receptor blocker significantly increased bioavailability of the benzodiazepine and resulted in higher plasma levels for the first 6 h after taking midazolam. This was accompanied by a greater soporific effect. 相似文献
5.
6.
Somatosensory nuclei in the brainstem of the rat: independent projections to the thalamus and cerebellum 总被引:2,自引:0,他引:2
The dorsal column nuclei and the sensory trigeminal nuclei project not only to the ventrobasal thalamus but also to the cerebellum. In this study the numbers and distribution of neurones projecting to these two regions were examined for the following nuclei: the rostral part of the main cuneate nucleus, the external cuneate nucleus, nucleus x, the principal sensory nucleus of the trigeminal nerve, and the oral, interpolar, and caudal subnuclei of the spinal nucleus of the trigeminal nerve. A thalamic projection from nucleus x and from the external cuneate nucleus was confirmed, and a distinct group of neurones projecting to the ventroposteromedial thalamus was distinguished near the ventromedial aspect of the principal sensory nucleus. Of the 165,000 neurones examined, only one was found to be double labelled. It was concluded that the populations of neurones that project to the ventrobasal thalamus and to the cerebellum are separate, and that somatosensory neurones in the brainstem do not send axon collaterals to both regions. 相似文献
7.
Jennifer M Griffith James R Sorenson J Michael Bowling Tracey Jennings-Grant 《Health education & behavior》2005,32(5):613-626
The Enhancing Patient Prenatal Education study tested the feasibility and educational impact of an interactive program for patient prenatal genetic screening and testing education. Patients at two private practices and one public health clinic participated (N = 207). The program collected knowledge and measures of anxiety before and after use of the tool. Time in various prenatal visit activities was collected prior to and after the introduction of the education tool. Providers completed an assessment of their experiences with patients who had used the program. Results indicate that patient knowledge significantly increased from pre to post (p = .0001) with no increase in anxiety (p = .31). Time in clinic activities, including overall visit time, increased. A majority of providers indicated that the program disrupted clinic flow. This assessment suggests that the program increases patient knowledge and does not increase patient anxiety. However, challenges remain to using this program in a clinic setting. 相似文献
8.
9.
Advanced glycosylation products quench nitric oxide and mediate defective endothelium-dependent vasodilatation in experimental diabetes. 总被引:48,自引:12,他引:36 下载免费PDF全文
Nitric oxide (an endothelium-derived relaxing factor) induces smooth muscle relaxation and is an important mediator in the regulation of vascular tone. Advanced glycosylation end products, the glucose-derived moieties that form nonenzymatically and accumulate on long-lived tissue proteins, have been implicated in many of the complications of diabetes and normal aging. We demonstrate that advanced glycosylation products quench nitric oxide activity in vitro and in vivo. Acceleration of the advanced glycosylation process in vivo results in a time-dependent impairment in endothelium-dependent relaxation. Inhibition of advanced glycosylation with aminoguanidine prevents nitric oxide quenching, and ameliorates the vasodilatory impairment. These results implicate advanced glycosylation products as important modulators of nitric oxide activity and endothelium-dependent relaxation. 相似文献
10.