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   22054篇
  免费   1409篇
  国内免费   39篇
耳鼻咽喉   146篇
儿科学   717篇
妇产科学   780篇
基础医学   2897篇
口腔科学   313篇
临床医学   3604篇
内科学   4046篇
皮肤病学   220篇
神经病学   2127篇
特种医学   360篇
外科学   1748篇
综合类   304篇
一般理论   35篇
预防医学   3136篇
眼科学   274篇
药学   1291篇
中国医学   13篇
肿瘤学   1491篇
  2023年   96篇
  2022年   161篇
  2021年   382篇
  2020年   229篇
  2019年   418篇
  2018年   432篇
  2017年   306篇
  2016年   384篇
  2015年   443篇
  2014年   658篇
  2013年   1038篇
  2012年   1468篇
  2011年   1487篇
  2010年   844篇
  2009年   817篇
  2008年   1448篇
  2007年   1421篇
  2006年   1432篇
  2005年   1448篇
  2004年   1376篇
  2003年   1354篇
  2002年   1326篇
  2001年   203篇
  2000年   206篇
  1999年   235篇
  1998年   270篇
  1997年   235篇
  1996年   198篇
  1995年   212篇
  1994年   178篇
  1993年   180篇
  1992年   175篇
  1991年   162篇
  1990年   148篇
  1989年   143篇
  1988年   132篇
  1987年   134篇
  1986年   103篇
  1985年   105篇
  1984年   152篇
  1983年   143篇
  1982年   173篇
  1981年   145篇
  1980年   160篇
  1979年   91篇
  1978年   95篇
  1977年   70篇
  1976年   68篇
  1974年   60篇
  1973年   45篇
排序方式: 共有10000条查询结果,搜索用时 218 毫秒
81.
The purpose of this study was to evaluate the ability of helical computed tomography (CT) to detect arterial injuries in gunshot wounds to the neck. In a blinded retrospective review, 54 helical CT scans of the cervical spine were evaluated for bullet/bone fragments, subcutaneous air, bullet path, hematoma, spine fractures, and pharyngoesophageal compromise. The distance of fragments to a major vessel was calculated. CT findings that correlated significantly with major arterial injury included the presence of fragments (bullet/bone) close to a major vessel (2.5 mm) and spine fractures. Visualizing fragments <5 mm from a vessel or a transcervical bullet trajectory predicted 12 of 13 major arterial injuries. We conclude that CT clearly depicts anatomic damage. Specific findings, such as the location of fragments and bullet trajectory adjacent to a vessel and spine fractures, indicate a higher probability of vascular damage, thus directing more definitive evaluation.  相似文献   
82.
83.
84.
85.
Age at first intercourse for a sample of adult white women using variables measured during childhood is predicted. Childhood predictors were measured at birth, and ages 5 and 9–11, using existing public-use data on the women. Median age at first intercourse for the sample was 17.5 years. Early family predictors, early developmental characteristics, and temperamental characteristics during childhood together could predict about a fourth of the variance in age at first intercourse. The strongest predictors were motor skills and nightmares at age 5, church attendance with family at age 9, and domineering and mature personality at age 9.This research was supported by grants R01-HD23454 and P30-HD05798 from the National Institute of Child Health and Human Development. An earlier version of this paper was presented at the annual meetings of the Population Association of America, Denver, Colorado, April 30–May 2, 1992.  相似文献   
86.
Cokeromyces recurvatus , a sporangiola-forming dimorphic is a rare cause of urogenital infection in humans. We report here a case of severe watery diarrhea due lo C. recurvains , which was treated successfully with high-dose oral nystatin therapy. We speculate that our patient was probably predisposed to infections due to opportunistic organisms, such as C. recurvatus , because of post-transplantation immunosuppression. To our knowledge, our patient represents the first documented case of diarrhea due to C. recurvatus in man und this ease highlights the potential pathogenic capability of this opportunistic organism in immunosuppressed patients.  相似文献   
87.
88.
Rohon-Beard cells are large, mechanosensory neurons located in the dorsal spinal cord of anamniote vertebrates. In most species studied to date, these cells die during development. We followed labeled Rohon-Beard cells in living zebrafish embryos and found that they degenerate slowly, over many days. During degeneration, the soma shrinks and finally disappears, and the processes become beady in appearance and finally break apart, but they do not retract. Zebrafish Rohon-Beard cells apparently fragment their DNA, as revealed by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) labeling, before undergoing degenerative morphologic changes. We also followed the development of labeled dorsal root ganglion neurons, as they are developing at the same stages that Rohon-Beard cells are degenerating. We found that, although axons of both cell types extend into similar regions, Rohon-Beard cells degenerate normally in mutants lacking dorsal root ganglia, providing evidence that interactions between the two cell types are not responsible for Rohon-Beard cell degeneration. Developmental Dynamics 229:30-41,2004.  相似文献   
89.
90.
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