首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1659584篇
  免费   127481篇
  国内免费   4002篇
耳鼻咽喉   21617篇
儿科学   53900篇
妇产科学   47005篇
基础医学   235616篇
口腔科学   47306篇
临床医学   142753篇
内科学   338410篇
皮肤病学   39674篇
神经病学   137557篇
特种医学   60991篇
外国民族医学   485篇
外科学   240019篇
综合类   34452篇
现状与发展   4篇
一般理论   556篇
预防医学   139667篇
眼科学   37408篇
药学   116549篇
  1篇
中国医学   4340篇
肿瘤学   92757篇
  2021年   15791篇
  2019年   16568篇
  2018年   23863篇
  2017年   17610篇
  2016年   19007篇
  2015年   21459篇
  2014年   29572篇
  2013年   42989篇
  2012年   60920篇
  2011年   64232篇
  2010年   36470篇
  2009年   33895篇
  2008年   57282篇
  2007年   60686篇
  2006年   60338篇
  2005年   59018篇
  2004年   56123篇
  2003年   53078篇
  2002年   49803篇
  2001年   79124篇
  2000年   81006篇
  1999年   66980篇
  1998年   18671篇
  1997年   16748篇
  1996年   16835篇
  1995年   15861篇
  1994年   14423篇
  1993年   13513篇
  1992年   49215篇
  1991年   46577篇
  1990年   44552篇
  1989年   42396篇
  1988年   38886篇
  1987年   37905篇
  1986年   35425篇
  1985年   33684篇
  1984年   25599篇
  1983年   21495篇
  1982年   13012篇
  1981年   11543篇
  1979年   22469篇
  1978年   15761篇
  1977年   13161篇
  1976年   12353篇
  1975年   12834篇
  1974年   15448篇
  1973年   15039篇
  1972年   14033篇
  1971年   12765篇
  1970年   12201篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Molnár  B.  Aroca  S.  Dobos  A.  Orbán  K.  Szabó  J.  Windisch  P.  Stähli  A.  Sculean  A. 《Clinical oral investigations》2022,26(12):7135-7142
Clinical Oral Investigations - To evaluate t he long-term outcomes following treatment of RT 1 multiple adjacent gingival recessions (MAGR) using the modified coronally advanced tunnel (MCAT) with...  相似文献   
2.
3.

The exercise pressor reflex is a feedback mechanism engaged upon stimulation of mechano- and metabosensitive skeletal muscle afferents. Activation of these afferents elicits a reflex increase in heart rate, blood pressure, and ventilation in an intensity-dependent manner. Consequently, the exercise pressor reflex has been postulated to be one of the principal mediators of the cardiorespiratory responses to exercise. In this updated review, we will discuss classical and recent advancements in our understating of the exercise pressor reflex function in both human and animal models. Particular attention will be paid to the afferent mechanisms and pathways involved during its activation, its effects on different target organs, its potential role in the abnormal cardiovascular response to exercise in diseased states, and the impact of age and biological sex on these responses. Finally, we will highlight some unanswered questions in the literature that may inspire future investigations in the field.

  相似文献   
4.
The coronavirus disease 2019 (COVID-19) pandemic has rapidly created widespread impacts on global health and the economy. Data suggest that women are less susceptible to severe illness. However, sex-disaggregated data are incomplete, leaving room for misinterpretation, and focusing only on biologic sex underestimates the gendered impact of the pandemic on women. This narrative review summarizes what is known about gender disparities during the COVID-19 pandemic and the economic, domestic, and health burdens along with overlapping vulnerabilities related to the pandemic. In addition, this review outlines recommended strategies that advocacy groups, community leaders, and policymakers should implement to mitigate the widening gender disparities related to COVID-19.  相似文献   
5.
6.
7.
8.
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   
9.
10.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号