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   2149015篇
  免费   165495篇
  国内免费   4334篇
耳鼻咽喉   29229篇
儿科学   65892篇
妇产科学   59069篇
基础医学   305322篇
口腔科学   61450篇
临床医学   190871篇
内科学   425676篇
皮肤病学   48518篇
神经病学   173610篇
特种医学   82728篇
外国民族医学   536篇
外科学   332535篇
综合类   46746篇
现状与发展   4篇
一般理论   678篇
预防医学   159656篇
眼科学   49180篇
药学   157430篇
  4篇
中国医学   4842篇
肿瘤学   124868篇
  2019年   15965篇
  2018年   23030篇
  2017年   17729篇
  2016年   19890篇
  2015年   22414篇
  2014年   31274篇
  2013年   46577篇
  2012年   63186篇
  2011年   66653篇
  2010年   39317篇
  2009年   37763篇
  2008年   63003篇
  2007年   66456篇
  2006年   67548篇
  2005年   65367篇
  2004年   62664篇
  2003年   60051篇
  2002年   58347篇
  2001年   114312篇
  2000年   117253篇
  1999年   97366篇
  1998年   25482篇
  1997年   22796篇
  1996年   22935篇
  1995年   21680篇
  1994年   19791篇
  1993年   18474篇
  1992年   73961篇
  1991年   70761篇
  1990年   68067篇
  1989年   65613篇
  1988年   60089篇
  1987年   58649篇
  1986年   54607篇
  1985年   52319篇
  1984年   38691篇
  1983年   32636篇
  1982年   18627篇
  1981年   16400篇
  1979年   34126篇
  1978年   23514篇
  1977年   19816篇
  1976年   18033篇
  1975年   19016篇
  1974年   23070篇
  1973年   22064篇
  1972年   20769篇
  1971年   19213篇
  1970年   18314篇
  1969年   17078篇
排序方式: 共有10000条查询结果,搜索用时 515 毫秒
1.
Quality of Life Research - The COVID-19 pandemic might add to the stressors experienced by people living with rheumatic diseases. This study aimed to examine rheumatic patients’ functional...  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.
9.
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   
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