全文获取类型
收费全文 | 23171篇 |
免费 | 3831篇 |
国内免费 | 277篇 |
专业分类
耳鼻咽喉 | 751篇 |
儿科学 | 761篇 |
妇产科学 | 450篇 |
基础医学 | 1670篇 |
口腔科学 | 560篇 |
临床医学 | 2882篇 |
内科学 | 5327篇 |
皮肤病学 | 733篇 |
神经病学 | 2837篇 |
特种医学 | 855篇 |
外国民族医学 | 1篇 |
外科学 | 5052篇 |
综合类 | 186篇 |
现状与发展 | 2篇 |
一般理论 | 5篇 |
预防医学 | 1830篇 |
眼科学 | 554篇 |
药学 | 886篇 |
中国医学 | 10篇 |
肿瘤学 | 1927篇 |
出版年
2023年 | 543篇 |
2022年 | 214篇 |
2021年 | 439篇 |
2020年 | 847篇 |
2019年 | 385篇 |
2018年 | 836篇 |
2017年 | 807篇 |
2016年 | 968篇 |
2015年 | 898篇 |
2014年 | 1244篇 |
2013年 | 1451篇 |
2012年 | 938篇 |
2011年 | 916篇 |
2010年 | 989篇 |
2009年 | 1166篇 |
2008年 | 922篇 |
2007年 | 802篇 |
2006年 | 928篇 |
2005年 | 718篇 |
2004年 | 608篇 |
2003年 | 615篇 |
2002年 | 557篇 |
2001年 | 605篇 |
2000年 | 583篇 |
1999年 | 543篇 |
1998年 | 395篇 |
1997年 | 418篇 |
1996年 | 457篇 |
1995年 | 418篇 |
1994年 | 279篇 |
1993年 | 223篇 |
1992年 | 393篇 |
1991年 | 426篇 |
1990年 | 333篇 |
1989年 | 379篇 |
1988年 | 306篇 |
1987年 | 269篇 |
1986年 | 285篇 |
1985年 | 280篇 |
1984年 | 227篇 |
1983年 | 192篇 |
1982年 | 156篇 |
1981年 | 138篇 |
1979年 | 166篇 |
1978年 | 159篇 |
1977年 | 146篇 |
1975年 | 160篇 |
1974年 | 135篇 |
1973年 | 124篇 |
1972年 | 122篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Kara S. Tanaka MD Veronica R. Andaya BA Steven W. Thorpe MD Kenneth R. Gundle MD James B. Hayden MD Yee-Cheen Duong MD Raffi S. Avedian MD David G. Mohler MD Lee J. Morse MD Melissa N. Zimel MD Richard J. O'Donnell MD Andrew Fang MD Robert Lor Randall MD Tina H. Tran BS Christin New BA Rosanna L. Wustrack MD other members of Study Group FORCE 《Journal of surgical oncology》2023,127(1):148-158
2.
3.
4.
5.
Margaret H. Lauerman Karen Irizarry Clint Sliker Brandon R. Bruns Ronald Tesoriero Thomas M. Scalea Deborah M. Stein 《Injury》2019,50(1):131-136
Background
Current blunt cerebrovascular injury (BCVI) grading grossly differentiates injury characteristics such as luminal stenosis (LS) and aneurysmal disease. The effect of increasing degree of LS beyond the current BCVI grading scale on stroke formation is unknown.Study Design
BCVI over a 3-year period were retrospectively reviewed. To investigate influence of LS beyond the BCVI grading scale within aneurysmal and non-aneurysmal BCVI, grade 2 BCVI were subdivided into BCVI with ≥ 25% and ≤ 50% LS and BCVI with > 50% and ≤ 99% LS. Grade 3 BCVI were subdivided into BCVI with pseudoaneurysm (PSA) without LS and BCVI with PSA and LS. We hypothesized increased LS beyond the current BCVI grade distinctions would be associated with higher rates of stroke formation.Results
312 BCVI were included, of which 140 were carotid BCVI and 172 vertebral BCVI. Sixteen carotid BCVI underwent endovascular intervention (EI) and 19 suffered a stroke. In carotid BCVI stroke rates increased sequentially with BCVI grade except in grade 3. There was a stroke rate of 12% in grade 1 carotid BCVI, 18% in grade 2, 6% in grade 3, and 31% in grade 4. In subgroup analysis for grade 2 carotid BCVI, BCVI with > 50% and ≤ 99% LS had higher rates of stroke (22% vs. 15%, p?=?0.44) than BCVI with ≥ 25% and ≤ 50% LS. In subgroup analysis of grade 3 carotid BCVI, BCVI with PSA and LS had higher rates of stroke (9% vs. 4%, p?=?0.48) than BCVI with PSA without LS. Higher rates of EI in grade 2 carotid BCVI with > 50% and ≤ 99% LS (22% vs. 5%, p?=?0.14) and grade 3 carotid BCVI with PSA and LS (35% vs. 4%, p?=?0.01) were noted in subgroup analysis.Conclusion
Higher percentage LS beyond the currently used BCVI grading scale has a non-significantly increased rate of stroke in both aneurysmal and non-aneurysmal BCVI. Grade 3 BCVI with PSA and LS seems to be a high-risk subgroup. Use of EI confounds modern measurement of stroke risk in higher LS BCVI. 相似文献6.
Alexander S. Dakos Ellen M. Walker Huai Jiang Barry E. Stein Benjamin A. Rowland 《The European journal of neuroscience》2019,50(11):3702-3712
Unilateral lesions of visual cortex have the secondary consequence of suppressing visual circuits in the midbrain superior colliculus (SC), collectively producing blindness in contralesional space (“hemianopia”). Recent studies have demonstrated that SC visual responses and contralesional vision can be reinstated by a non‐invasive multisensory training procedure in which spatiotemporally concordant visual‐auditory pairs are repeatedly presented within the blind hemifield. Despite this recovery of visual responsiveness, the loss of visual cortex was expected to result in permanent deficits in that hemifield, especially when visual events in both hemifields compete for attention and access to the brain's visuomotor circuitry. This was evaluated in the present study in a visual choice paradigm in which the two visual hemifields of recovered cats were simultaneously stimulated with equally valent visual targets. Surprisingly, the expected disparity was not found, and some animals even preferred stimuli presented in the previously blind hemifield. This preference persisted across multiple stimulus intensity levels and there was no indication that animals were less aware of cues in the previously blind hemifield than in its spared counterpart. Furthermore, when auditory cues were combined with visual cues, the enhanced performance they produced on a visual task was no greater in the normal than in the previously blind hemifield. These observations suggest that the multisensory rehabilitation paradigm revealed greater inherent visual information processing potential in the previously blind hemifield than was believed possible given the loss of visual cortex. 相似文献
7.
8.
9.
10.
Fiene Marie Kuijper Uma V. Mahajan Seul Ku Daniel A.N. Barbosa Sheila M. Alessi Sherman C. Stein Kyle M. Kampman Brandon S. Bentzley Casey H. Halpern 《Neuromodulation》2022,25(2):253-262
ObjectivesCocaine is the second most frequently used illicit drug worldwide (after cannabis), and cocaine use disorder (CUD)-related deaths increased globally by 80% from 1990 to 2013. There is yet to be a regulatory-approved treatment. Emerging preclinical evidence indicates that deep brain stimulation (DBS) of the nucleus accumbens may be a therapeutic option. Prior to expanding the costly investigation of DBS for treatment of CUD, it is important to ensure societal cost-effectiveness.AimsWe conducted a threshold and cost-effectiveness analysis to determine the success rate at which DBS would be equivalent to contingency management (CM), recently identified as the most efficacious therapy for treatments of CUDs.Materials and MethodsQuality of life, efficacy, and safety parameters for CM were obtained from previous literature. Costs were calculated from a societal perspective. Our model predicted the utility benefit based on quality-adjusted life-years (QALYs) and incremental-cost-effectiveness ratio resulting from two treatments on a one-, two-, and five-year timeline.ResultsOn a one-year timeline, DBS would need to impart a success rate (ie, cocaine free) of 70% for it to yield the same utility benefit (0.492 QALYs per year) as CM. At no success rate would DBS be more cost-effective (incremental-cost-effectiveness ratio <$50,000) than CM during the first year. Nevertheless, as DBS costs are front loaded, DBS would need to achieve success rates of 74% and 51% for its cost-effectiveness to exceed that of CM over a two- and five-year period, respectively.ConclusionsWe find DBS would not be cost-effective in the short term (one year) but may be cost-effective in longer timelines. Since DBS holds promise to potentially be a cost-effective treatment for CUDs, future randomized controlled trials should be performed to assess its efficacy. 相似文献