全文获取类型
收费全文 | 5170篇 |
免费 | 284篇 |
国内免费 | 34篇 |
专业分类
耳鼻咽喉 | 157篇 |
儿科学 | 77篇 |
妇产科学 | 258篇 |
基础医学 | 651篇 |
口腔科学 | 56篇 |
临床医学 | 453篇 |
内科学 | 1524篇 |
皮肤病学 | 52篇 |
神经病学 | 445篇 |
特种医学 | 90篇 |
外科学 | 626篇 |
综合类 | 33篇 |
一般理论 | 1篇 |
预防医学 | 180篇 |
眼科学 | 68篇 |
药学 | 409篇 |
中国医学 | 4篇 |
肿瘤学 | 404篇 |
出版年
2023年 | 25篇 |
2022年 | 144篇 |
2021年 | 369篇 |
2020年 | 85篇 |
2019年 | 126篇 |
2018年 | 152篇 |
2017年 | 111篇 |
2016年 | 137篇 |
2015年 | 167篇 |
2014年 | 219篇 |
2013年 | 289篇 |
2012年 | 408篇 |
2011年 | 425篇 |
2010年 | 207篇 |
2009年 | 142篇 |
2008年 | 348篇 |
2007年 | 381篇 |
2006年 | 330篇 |
2005年 | 309篇 |
2004年 | 331篇 |
2003年 | 305篇 |
2002年 | 217篇 |
2001年 | 20篇 |
2000年 | 19篇 |
1999年 | 23篇 |
1998年 | 25篇 |
1997年 | 14篇 |
1996年 | 9篇 |
1995年 | 12篇 |
1994年 | 13篇 |
1993年 | 8篇 |
1992年 | 12篇 |
1991年 | 6篇 |
1990年 | 9篇 |
1989年 | 8篇 |
1988年 | 8篇 |
1987年 | 4篇 |
1986年 | 16篇 |
1985年 | 6篇 |
1983年 | 3篇 |
1982年 | 5篇 |
1981年 | 8篇 |
1980年 | 5篇 |
1979年 | 2篇 |
1978年 | 4篇 |
1977年 | 3篇 |
1976年 | 3篇 |
1975年 | 3篇 |
1971年 | 2篇 |
1968年 | 2篇 |
排序方式: 共有5488条查询结果,搜索用时 15 毫秒
51.
This paper presents experimental investigations of reinforced concrete (RC) beams flexurally strengthened with carbon fiber reinforced polymer (CFRP) strips. Seven 3300 mm × 250 mm × 150 mm beams of the same design, with the tension reinforcement ratio of 1.01%, were tested. The beams differed in the way they were strengthened: one of the beams was the reference, two beams were passively strengthened as precracked (series B-I), two beams were passively strengthened as unprecracked (series B-II) and two beams were actively strengthened as unprecracked (series B-III). Moreover, the strengthening parameters differed between the particular series. The parameters were: CFRP strip cross-sectional areas (series B-I, B-II) or prestressing forces (series B-III). The beams were statically loaded, up to the assumed force value, in the three-point bending test and deflections at midspan were registered. After unloading the beams were suspended on flexible ropes (the free-free beam system) and their eigenfrequencies were measured using operational modal analysis (OMA). The static measurements (deflections) and the dynamic measurements (eigenfrequencies) were conducted for the adopted loading steps until failure. Static stiffnesses and dynamic stiffnesses were calculated on the basis of respectively the deflections and the eigenfrequencies. The qualitative and quantitative differences between the parameters are described. 相似文献
52.
53.
54.
55.
Rakowski Tomasz Siudak Zbigniew Dziewierz Artur Plens Krzysztof Kleczyński Paweł Dudek Dariusz 《Journal of thrombosis and thrombolysis》2018,45(1):151-157
Journal of Thrombosis and Thrombolysis - According to guidelines, it is recommended to give P2Y12 inhibitors (preferably ticagrelor or prasugrel) at the time of first medical contact in patients... 相似文献
56.
Validation of a semi‐automatic co‐registration of MRI scans in patients with brain tumors during treatment follow‐up 下载免费PDF全文
Anouk van der Hoorn Jiun‐Lin Yan Timothy J. Larkin Natalie R. Boonzaier Tomasz Matys Stephen J. Price 《NMR in biomedicine》2016,29(7):882-889
There is an expanding research interest in high‐grade gliomas because of their significant population burden and poor survival despite the extensive standard multimodal treatment. One of the obstacles is the lack of individualized monitoring of tumor characteristics and treatment response before, during and after treatment. We have developed a two‐stage semi‐automatic method to co‐register MRI scans at different time points before and after surgical and adjuvant treatment of high‐grade gliomas. This two‐stage co‐registration includes a linear co‐registration of the semi‐automatically derived mask of the preoperative contrast‐enhancing area or postoperative resection cavity, brain contour and ventricles between different time points. The resulting transformation matrix was then applied in a non‐linear manner to co‐register conventional contrast‐enhanced T1‐weighted images. Targeted registration errors were calculated and compared with linear and non‐linear co‐registered images. Targeted registration errors were smaller for the semi‐automatic non‐linear co‐registration compared with both the non‐linear and linear co‐registered images. This was further visualized using a three‐dimensional structural similarity method. The semi‐automatic non‐linear co‐registration allowed for optimal correction of the variable brain shift at different time points as evaluated by the minimal targeted registration error. This proposed method allows for the accurate evaluation of the treatment response, essential for the growing research area of brain tumor imaging and treatment response evaluation in large sets of patients. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
57.
Barbara Jasiewicz Jacek Pietraszek Sławomir Duda Szymon Pietrzak Błażej Pruszczyński Tomasz Parol Tomasz Potaczek Aneta Gądek-Moszczak 《Foot and Ankle Surgery》2021,27(4):371-376
BackgroundFoot bones in children have more rounded shapes in radiograms than adults. Thus, the goal of this work was assessing inter- and intra-observer reliability in paediatric forefoot angle measurements.Material and methodsSix forefoot angles in 34 AP standing paediatric foot radiographs were measured by 5 researchers. A classic statistical analysis with use of IBM SPSS Statistics 25 was performed and a new method with two-way analysis of variance was applied.ResultsResults of statistical analysis revealed the properties of a subjective assessment related to specific angles. Kilmartin’s angle, calcaneus-fifth metatarsal angle and first ray angle are the most reliable; metatarsus adductus angle should be used with great caution in pediatric population. Engel’s angle is the most difficult for measuring and measurement error is the highest.ConclusionThe power of paediatric forefoot measurements is various. Several angles are reliable, while Engle’s angle is the most doubtful. 相似文献
58.
59.
Aleksander Ku Mikoaj Radziszewski Aleksandra Glina Konrad Szymaski Beata Jurecka‐Lubieniecka Edyta Pawlak‐Adamska Dorota Kula Natalia Wawrusiewicz‐Kurylonek Joanna Ku Piotr Mikiewicz Rafa Poski Marek Bolanowski Jacek Daroszewski Barbara Jarzb Artur Bossowski Tomasz Bednarczuk 《Clinical endocrinology》2019,90(2):320-327
60.
Jan Detka Joanna Ślusarczyk Anna Kurek Mateusz Kucharczyk Tomasz Adamus Paweł Konieczny Marta Kubera Agnieszka Basta-Kaim Władysław Lasoń Bogusława Budziszewska 《Pharmacological reports : PR》2019,71(2):338-346