全文获取类型
收费全文 | 1073994篇 |
免费 | 90045篇 |
国内免费 | 17051篇 |
专业分类
耳鼻咽喉 | 14635篇 |
儿科学 | 26721篇 |
妇产科学 | 27922篇 |
基础医学 | 149469篇 |
口腔科学 | 28985篇 |
临床医学 | 105362篇 |
内科学 | 195921篇 |
皮肤病学 | 19065篇 |
神经病学 | 81885篇 |
特种医学 | 43156篇 |
外国民族医学 | 309篇 |
外科学 | 156870篇 |
综合类 | 59516篇 |
现状与发展 | 57篇 |
一般理论 | 282篇 |
预防医学 | 79616篇 |
眼科学 | 26998篇 |
药学 | 86720篇 |
194篇 | |
中国医学 | 13856篇 |
肿瘤学 | 63551篇 |
出版年
2022年 | 11181篇 |
2021年 | 16337篇 |
2020年 | 11745篇 |
2019年 | 12633篇 |
2018年 | 15133篇 |
2017年 | 12709篇 |
2016年 | 13003篇 |
2015年 | 17742篇 |
2014年 | 23325篇 |
2013年 | 27186篇 |
2012年 | 38276篇 |
2011年 | 41325篇 |
2010年 | 24140篇 |
2009年 | 21044篇 |
2008年 | 33297篇 |
2007年 | 35280篇 |
2006年 | 35310篇 |
2005年 | 35123篇 |
2004年 | 30434篇 |
2003年 | 29182篇 |
2002年 | 27207篇 |
2001年 | 40179篇 |
2000年 | 41286篇 |
1999年 | 36143篇 |
1998年 | 12603篇 |
1997年 | 11941篇 |
1996年 | 11211篇 |
1995年 | 10557篇 |
1994年 | 9806篇 |
1992年 | 28370篇 |
1991年 | 27554篇 |
1990年 | 26791篇 |
1989年 | 25617篇 |
1988年 | 24101篇 |
1987年 | 23665篇 |
1986年 | 22380篇 |
1985年 | 21565篇 |
1984年 | 16672篇 |
1983年 | 14208篇 |
1979年 | 16849篇 |
1978年 | 12156篇 |
1977年 | 10218篇 |
1976年 | 9353篇 |
1975年 | 10183篇 |
1974年 | 12687篇 |
1973年 | 12171篇 |
1972年 | 11575篇 |
1971年 | 10709篇 |
1970年 | 10232篇 |
1969年 | 9930篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
ObjectiveEach pulmonary segment is an anatomical and functional unit. However, it is fundamentally difficult to precisely distinguish every pulmonary segment using the conventional pulmonary intersegmental planes from computed tomography images. Building arteriopulmonary segments is likely to be an effective way to identify pulmonary segments.MethodsThe thoracic computed tomography images of 40 patients were collected. The anatomic structures of interest were extracted in the transverse, sagittal, and coronal planes using the semi-automated segmentation tools provided by Amira software. The intrapulmonary vessels were subsequently segmented and reconstructed. The distributions of the pulmonary arteries, veins, and bronchi were observed. In patients with pulmonary masses, the mass was also reconstructed.ResultsThe three-dimensional reconstructed images showed the branches of the pulmonary artery ramified up to their eighth order covering the entire lung as well as evident intersegmental gaps without pulmonary arteries. The segmental artery was closely accompanied by the segmental bronchi in 486 pulmonary segments (90% of total number of segments). The size and spatial location of the pulmonary mass within a pulmonary segment were also clearly visible.ConclusionsDemarcation of arteriopulmonary segments can be used to precisely distinguish every pulmonary segment and provide its detailed anatomical structure before pulmonary segmentectomy. 相似文献
2.
3.
Patrick W. Keeley Mikayla C. Lebo Jordan D. Vieler Jason J. Kim Ace J. St. John Benjamin E. Reese 《The Journal of neuroscience》2021,41(1):103
Amacrine cells of the retina are conspicuously variable in their morphologies, their population demographics, and their ensuing functions. Vesicular glutamate transporter 3 (VGluT3) amacrine cells are a recently characterized type of amacrine cell exhibiting local dendritic autonomy. The present analysis has examined three features of this VGluT3 population, including their density, local distribution, and dendritic spread, to discern the extent to which these are interrelated, using male and female mice. We first demonstrate that Bax-mediated cell death transforms the mosaic of VGluT3 cells from a random distribution into a regular mosaic. We subsequently examine the relationship between cell density and mosaic regularity across recombinant inbred strains of mice, finding that, although both traits vary across the strains, they exhibit minimal covariation. Other genetic determinants must therefore contribute independently to final cell number and to mosaic order. Using a conditional KO approach, we further demonstrate that Bax acts via the bipolar cell population, rather than cell-intrinsically, to control VGluT3 cell number. Finally, we consider the relationship between the dendritic arbors of single VGluT3 cells and the distribution of their homotypic neighbors. Dendritic field area was found to be independent of Voronoi domain area, while dendritic coverage of single cells was not conserved, simply increasing with the size of the dendritic field. Bax-KO retinas exhibited a threefold increase in dendritic coverage. Each cell, however, contributed less dendrites at each depth within the plexus, intermingling their processes with those of neighboring cells to approximate a constant volumetric density, yielding a uniformity in process coverage across the population.SIGNIFICANCE STATEMENT Different types of retinal neuron spread their processes across the surface of the retina to achieve a degree of dendritic coverage that is characteristic of each type. Many of these types achieve a constant coverage by varying their dendritic field area inversely with the local density of like-type neighbors. Here we report a population of retinal amacrine cells that do not develop dendritic arbors in relation to the spatial positioning of such homotypic neighbors; rather, this cell type modulates the extent of its dendritic branching when faced with a variable number of overlapping dendritic fields to approximate a uniformity in dendritic density across the retina. 相似文献
4.
“三全育人”视角下思政教育机制实践与探索——“杏林成长导师”计划的构建 《医学教育管理》2021,7(6):656-660
“三全育人”是高校思政教育工作的关键一环,也是中医药高校推动思政教育的重要内容。以“三全育人”为视角对北京中医药大学思想政治教育举措“杏林成长导师”计划路径、内容深入分析,运用统计分析和文献研究方法,剖析该计划对中医学专业大学生的学业、思想和实践等多个层面的现实成效,从而为“三全育人”理念在中医药院校制度建构中的应用提供新的视角与方法。 相似文献
5.
6.
7.
8.
9.
10.