全文获取类型
收费全文 | 952篇 |
免费 | 144篇 |
国内免费 | 10篇 |
专业分类
耳鼻咽喉 | 15篇 |
儿科学 | 94篇 |
妇产科学 | 13篇 |
基础医学 | 84篇 |
口腔科学 | 39篇 |
临床医学 | 150篇 |
内科学 | 217篇 |
皮肤病学 | 9篇 |
神经病学 | 39篇 |
特种医学 | 166篇 |
外科学 | 132篇 |
综合类 | 34篇 |
预防医学 | 39篇 |
眼科学 | 1篇 |
药学 | 21篇 |
中国医学 | 5篇 |
肿瘤学 | 48篇 |
出版年
2022年 | 2篇 |
2021年 | 12篇 |
2020年 | 6篇 |
2019年 | 7篇 |
2018年 | 35篇 |
2017年 | 42篇 |
2016年 | 38篇 |
2015年 | 34篇 |
2014年 | 37篇 |
2013年 | 63篇 |
2012年 | 29篇 |
2011年 | 25篇 |
2010年 | 60篇 |
2009年 | 53篇 |
2008年 | 31篇 |
2007年 | 31篇 |
2006年 | 19篇 |
2005年 | 14篇 |
2004年 | 11篇 |
2003年 | 12篇 |
2002年 | 8篇 |
2001年 | 18篇 |
2000年 | 7篇 |
1999年 | 6篇 |
1998年 | 59篇 |
1997年 | 53篇 |
1996年 | 55篇 |
1995年 | 49篇 |
1994年 | 28篇 |
1993年 | 40篇 |
1992年 | 17篇 |
1991年 | 18篇 |
1990年 | 19篇 |
1989年 | 15篇 |
1988年 | 24篇 |
1987年 | 21篇 |
1986年 | 15篇 |
1985年 | 10篇 |
1984年 | 12篇 |
1983年 | 16篇 |
1982年 | 3篇 |
1981年 | 16篇 |
1980年 | 8篇 |
1979年 | 1篇 |
1978年 | 2篇 |
1977年 | 10篇 |
1976年 | 9篇 |
1975年 | 3篇 |
1971年 | 1篇 |
1938年 | 1篇 |
排序方式: 共有1106条查询结果,搜索用时 312 毫秒
121.
Background
Selective serotonin reuptake inhibitors (SSRIs), a popular class of antidepressants, may increase breast cancer risk by stimulating the secretion of prolactin, a potential tumour promoter. We evaluated the effects of duration of SSRI use, cumulative dose, and latency on the risk of breast cancer by conducting a population-based case-control study utilizing Saskatchewan health databases. 相似文献122.
Maurits PA van Meer Kajo van der Marel Willem M Otte Jan Willem Berkelbach van der Sprenkel Rick M Dijkhuizen 《Journal of cerebral blood flow and metabolism》2010,30(10):1707-1711
This study shows a significant correlation between functional connectivity, as measured with resting-state functional magnetic resonance imaging (MRI), and neuroanatomical connectivity, as measured with manganese-enhanced MRI, in rats at 10 weeks after unilateral stroke and in age-matched controls. Reduced interhemispheric functional connectivity between the contralesional primary motor cortex (M1) and ipsilesional sensorimotor cortical regions was accompanied by a decrease in transcallosal manganese transfer from contralesional M1 to the ipsilesional sensorimotor cortex after a large unilateral stroke. Increased intrahemispheric functional connectivity in the contralesional sensorimotor cortex was associated with locally enhanced neuroanatomical tracer uptake, which underlines the strong link between functional and structural reorganization of neuronal networks after stroke. 相似文献
123.
高压氧综合治疗糖尿病足的临床疗效观察 总被引:1,自引:0,他引:1
糖尿病足(diabetic foot,DF)是常见的糖尿病慢性合并症之一,也是导致糖尿病人截肢致残的主要原因.近年来,糖尿病患病率逐年增高,使糖尿病足的患病率也呈逐年上升的趋势. 相似文献
124.
125.
126.
127.
128.
Sumatriptan blocks spreading depression in isolated chick retina 总被引:1,自引:0,他引:1
PA Maranhâo-Filho H Martins-Ferreira MB Vincent LJC Ribeiro SAP Novis 《Cephalalgia : an international journal of headache》1997,17(8):822-825
Spreading depression is a neurohumoral phenomenon that has been related to the pathophysiology of migraine. The recently introduced 5HT1D agonist anti-migraine compound sumatriptan blocks neurogenic extravasation and induces cerebral vasoconstriction, but the actual mechanism of action against migraine remains obscure. Retinal spreading depression (RSD) velocity has been measured in isolated chick retinas in the presence of 0.05-2.00:nM sumatriptan. This drug reversibly blocks RSD in a concentration-dependent manner. Since the preparation is blood-vessel free, this effect must be related to the nervous tissue. 相似文献
129.
Cause of signal loss in MR images of old hemorrhagic lesions 总被引:2,自引:0,他引:2
Old hemorrhagic lesions in the brain are characteristically surrounded by a band of hemosiderin-containing tissue. This region is typically of low signal intensity on long-echo-time (TE) radio-frequency (RF) spin-echo magnetic resonance (MR) images and on gradient-echo MR images. To determine the cause of signal loss in this band, the authors measured the signal that arises from imaging such a region with use of an RF spin-echo technique with a 180 degrees pulse incrementally displaced from TE/2. The incremental loss of signal was small. Using an agar phantom containing iron particles, the authors also showed that signal loss results primarily from diffusion in magnetic gradients. They conclude that most signal loss in the dark band surrounding areas of late-stage hemorrhage arises from diffusion in areas of magnetic inhomogeneity. 相似文献
130.
JD Carroll M Reidy PA Savundra N Cleave J McAinsh 《Cephalalgia : an international journal of headache》1990,10(2):101-105
A randomized double-blind, cross-over study using treatment periods of 12 weeks with a 2-week washout, comparing two long-acting formulations of propranolol ('Inderal' LA 160 mg daily and Half-'Inderal' LA 80 mg daily) was performed after a placebo run-in of 4 weeks on 51 patients. The study indicated that both long-acting formulations were significantly better than placebo in reducing the frequency of migraine attacks (p less than 0.01). After 12 weeks there was a significantly lower (p = 0.03) frequency of migraine attacks in patients on the higher dose formulation than in those on the lower dose formulation. There was no significant difference in the frequency of side effects produced by the two formulations. 相似文献