全文获取类型
收费全文 | 1974篇 |
免费 | 129篇 |
国内免费 | 6篇 |
专业分类
耳鼻咽喉 | 9篇 |
儿科学 | 56篇 |
妇产科学 | 48篇 |
基础医学 | 267篇 |
口腔科学 | 100篇 |
临床医学 | 198篇 |
内科学 | 311篇 |
皮肤病学 | 152篇 |
神经病学 | 85篇 |
特种医学 | 231篇 |
外科学 | 254篇 |
综合类 | 81篇 |
预防医学 | 121篇 |
眼科学 | 27篇 |
药学 | 83篇 |
中国医学 | 25篇 |
肿瘤学 | 61篇 |
出版年
2022年 | 13篇 |
2021年 | 14篇 |
2020年 | 13篇 |
2019年 | 21篇 |
2018年 | 38篇 |
2017年 | 35篇 |
2016年 | 24篇 |
2015年 | 35篇 |
2014年 | 58篇 |
2013年 | 92篇 |
2012年 | 90篇 |
2011年 | 97篇 |
2010年 | 73篇 |
2009年 | 72篇 |
2008年 | 86篇 |
2007年 | 105篇 |
2006年 | 64篇 |
2005年 | 65篇 |
2004年 | 45篇 |
2003年 | 55篇 |
2002年 | 42篇 |
2001年 | 48篇 |
2000年 | 38篇 |
1999年 | 44篇 |
1998年 | 64篇 |
1997年 | 63篇 |
1996年 | 46篇 |
1995年 | 31篇 |
1994年 | 35篇 |
1993年 | 37篇 |
1992年 | 33篇 |
1991年 | 37篇 |
1990年 | 28篇 |
1989年 | 50篇 |
1988年 | 49篇 |
1987年 | 59篇 |
1986年 | 45篇 |
1985年 | 48篇 |
1984年 | 22篇 |
1983年 | 17篇 |
1982年 | 19篇 |
1981年 | 16篇 |
1980年 | 13篇 |
1979年 | 18篇 |
1978年 | 11篇 |
1977年 | 15篇 |
1976年 | 13篇 |
1975年 | 9篇 |
1974年 | 8篇 |
1973年 | 12篇 |
排序方式: 共有2109条查询结果,搜索用时 15 毫秒
101.
102.
目的 评价改良小梁切除术治疗伴有高眼压及大瞳孔的急性房角关闭的临床疗效。方法收集2005年1月至2009年3月中山大学中山眼科中心青光眼专业实施改良小梁切除术治疗伴有高眼压及大瞳孔的急性房角关闭21例(21眼)的临床资料,对术后并发症及手术前后的眼压、视力、瞳孔等进行统计分析。 结果 术前眼压(48.25±3.14) mmHg,平均用降眼压药种类3.35种,明显高于出院时眼压(10.47±1.15)mmHg(t=11.4573,P<0.01)及术后3个月眼压(13.86±0.93) mmHg(t=11.2641,P<0.01)。出院视力(0.09±0.05)与术前视力(0.11±0.06)差异无统计学意义(沁0.8702,P= 0.3913),术后3个月视力(0.21±0.04)则稍好于术前(t=-2.7907,P=0.0112)。术前瞳孔垂直径(5.81±0.23) mm与出院时瞳孔垂直径(5.92±0.21 )mm差异无统计学意义(t=-1.5013,P=0.1672)。无严重并发症发生。 结论 改良小梁切除术是治疗伴有高眼压及大瞳孔的急性房角关闭的有效方法,术中分次放房水、巩膜瓣调节缝线、术毕形成前房等措施可有效减少严重并发症的发生。 相似文献
103.
Transforming growth factor beta-coated platinum coils for endovascular treatment of aneurysms: an animal study 总被引:5,自引:0,他引:5
de Gast AN Altes TA Marx WF Do HM Helm GA Kallmes DF 《Neurosurgery》2001,49(3):690-4; discussion 694-6
OBJECTIVE: To test the hypothesis that coating platinum coils with transforming growth factor beta (TGFbeta) would improve the cellular proliferation within experimental aneurysms relative to uncoated coils. MATERIALS AND METHODS: Elastase-induced saccular aneurysms were created in 12 New Zealand White rabbits. These aneurysms were embolized with platinum coils, either "control" (unmodified) coils or "test" (coated with TGFbeta) coils. Subjects were killed either 2 weeks (n = 3, control; n = 3, test) or 6 weeks (n = 3, control; n = 3, test) after embolization. Aneurysm tissue was embedded in plastic, sectioned, and stained with hematoxylin and eosin. The thickness of tissue covering the coils at the coil-lumen interface was measured by use of a digital microscope, and was compared between groups by use of the Student's t test (P < or = 0.05). RESULTS: Two-week implantation samples demonstrated mean thickness of tissue overlying TGFbeta-coated coils of 36+/-15 microm and mean thickness of overlying control coils of 3+/-5 microm, indicating significantly thicker tissue growth covering test versus control coils (P = 0.02). Six-week implantation samples demonstrated mean thickness of tissue overlying TGFbeta-coated coils of 86+/-74 microm versus mean thickness overlying control coils of 37+/-6 mu; this difference did not reach statistical significance (P = 0.30). Thickness of tissue covering TGFbeta-coated coils did not change significantly from 2 to 6 weeks (P = 0.31). Tissue thickness over control coils increased significantly between 2 and 6 weeks (P = 0.002). CONCLUSION: TGFbeta-coated platinum coils undergo earlier cellular coverage than standard platinum coils, but differences in coverage between coated and control coils are no longer present at later time points. These data suggest that improvements in intra-aneurysmal cellular proliferation resulting from coil modifications, although significant in the early postembolization phase, may dissipate over time. 相似文献
104.
Ysbrand D. Van Der Werf Els Van Der Helm Menno M. Schoonheim Arne Ridderikhoff Eus J. W. Van Someren 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(45):18926-18930
Numerous studies have shown that sleep enhances memory for motor skills learned through practice. Motor skills can, however, also be learned through observation, a process possibly involving the mirror neuron system. We investigated whether motor skill enhancement through prior observation requires sleep to follow the observation, either immediately or after a delay, to consolidate the procedural memory. Sequence-specific fingertapping performance was tested in 64 healthy subjects in a balanced design. Electromyography verified absence of overt or subliminal hand muscle activations during observation. The results show that immediate sleep is necessary for the enhancement of a motor skill through prior observation. Immediate sleep improved the speed of subsequent performance by 22 ± 11% (mean ± SEM) (P = 0.04) and reduced the error rate by 42 ± 19% (P = 0.02). In contrast, no performance gains occurred if sleep was initiated more than 12 h after observation. A second study on 64 subjects ruled out explicit familiarity with the sequence or the spatiotemporal rhythm of the sequence to underlie performance improvements. The sleep-dependent observational motor learning enhancement is at least similar to that previously reported for implicit and declarative memory. The apparent prerequisite of observing real movements indicates that subjects transfer experience obtained through observation of movements to subsequent self-initiated movements, in the absence of practice. Moreover, the consolidation of this transfer requires an early sleep window. These findings could improve learning new motor skills in athletes and children, but also in patients having to remaster skills following stroke or injury. 相似文献
105.
目的建立大鼠心肌梗死后心力衰竭模型,并进行评估,以提高存活率和成功率。方法分批对70只SD大鼠行冠状动脉左前降支结扎术,同时设15只假手术组,并计算死亡率。于4周时行血流动力学检查,检测心率(HR)、左心室舒张末压(LVEDP)、左室压力最大上升速率(+dp/dtmax)以及左室压力最大下降速率(-dp/dtmax)。结果4周时模型组HR、+dp/dtmax和-dp/dtmax绝对值均低于假手术组(P<0.05),LVEDP则高于假手术组(P<0.05)。随着手术大鼠例数增多,存活率得到提高(P<0.05)。结论心肌梗死后4周形成心力衰竭模型,通过经口气管插管法、选择结扎冠状动脉分支末梢部位、增加手术操作熟练程度,可提高动物存活率。 相似文献
106.
目的:评估人工流产(指手术流产)对乳腺癌危险性的可能影响。方法:研究在上海267040例妇女的一项乳房自我检查随机试验的队列人群中进行,由队列研究和巢式病例对照研究两部分组成。结果:依据基线调查表采集的资料分析,人工流产不增加乳腺癌危险性。调整潜在的混淆因素后,OR=1.06(95%CI:0.91~1.25)。人工流产次数增加无危险性趋势增加。从更详细的652例乳腺癌病例和694例对照资料分析,得出相似的结果。人工流产发生在首次生育后不增加危险性;少数妇女在首次生育前人工流产以及妊娠13周后人工流产,虽然被观察到危险性有增加,但无显著性统计学意义。结论:在中国,人工流产不是乳腺癌发生的重要原因。 相似文献
107.
108.
109.
110.
A Papadopoulou MO Rawashdeh GA Brown AS McNeish IW Booth 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(1):79-83
The short- and long-term effects of an elemental diet in children with acute Crohn's disease were compared with those of prednisolone in historical controls. Clinical remission was induced in 25 of 30 and in 18 of 28 episodes treated for six weeks with an elemental diet and prednisolone. Patients with proximal disease had longer remission after treatment with an elemental diet (p < 0.05) than did patients with colonic disease after treatment with prednisolone (p < 0.01). Disease activity index score improved in both groups compared with the pretreatment scores (p < 0.05). However, the improvement in the elemental diet group was significantly better than in the prednisolone group (p < 0.001). Changes in linear growth were better after treatment with an elemental diet compared with steroids (p < 0.001). Serum albumin and haematocrit concentrations all improved significantly in the children treated with an elemental diet (p < 0.001) but not in those treated with steroids. Thus an elemental diet was better than prednisolone in proximal disease and confirmed improved growth and nutritional status. 相似文献