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   2399篇
  免费   224篇
  国内免费   11篇
耳鼻咽喉   10篇
儿科学   138篇
妇产科学   43篇
基础医学   257篇
口腔科学   52篇
临床医学   354篇
内科学   496篇
皮肤病学   23篇
神经病学   118篇
特种医学   260篇
外科学   281篇
综合类   57篇
一般理论   6篇
预防医学   197篇
眼科学   47篇
药学   162篇
  1篇
中国医学   1篇
肿瘤学   131篇
  2021年   20篇
  2020年   17篇
  2019年   31篇
  2018年   50篇
  2017年   28篇
  2016年   29篇
  2015年   45篇
  2014年   50篇
  2013年   57篇
  2012年   75篇
  2011年   92篇
  2010年   79篇
  2009年   74篇
  2008年   60篇
  2007年   64篇
  2006年   55篇
  2005年   65篇
  2004年   49篇
  2003年   58篇
  2002年   65篇
  2001年   52篇
  2000年   53篇
  1999年   57篇
  1998年   100篇
  1997年   107篇
  1996年   109篇
  1995年   86篇
  1994年   70篇
  1993年   57篇
  1992年   51篇
  1991年   53篇
  1990年   34篇
  1989年   60篇
  1988年   61篇
  1987年   68篇
  1986年   45篇
  1985年   51篇
  1984年   40篇
  1983年   37篇
  1982年   21篇
  1981年   30篇
  1980年   17篇
  1979年   32篇
  1977年   24篇
  1976年   24篇
  1975年   23篇
  1974年   15篇
  1972年   17篇
  1971年   16篇
  1969年   21篇
排序方式: 共有2634条查询结果,搜索用时 15 毫秒
1.
2.
3.
Background: t(14; 18)/bcl-2 gene rearrangement (R) is claimedto impart a worse rate of complete remission and disease-freesurvival in diffuse large cell lymphoma (DLCL). DEL 6q has alsobeen associated with poor outcome. Design: Retrospective studyof 54 patients with either diffuse large cell or immunoblasticlymphoma who had cytogenetics and/or molecular studies performed.Results: Patient characteristics, complete remission rate, andtime to treatment failure (TTF) were similar at three year follow-upfor groups with and without t(14; 18)/BCL-2R Survival was worsefor the former but the difference was not statistically significant.For DEL 6q, patient characteristics and survival rates weresimilar at three year follow-up for patients with and withoutthe abnormality. TTF was worse for the former but this was notstatistically significant. Conclusion: This study, with equalor greater number of patients with t(14; 18) than previous reports,fails to show a worse prognosis for patients with the t(14;18) chromosomal abnormality. A definite association will awaitfurther accrual of patients and a meaningul multivariate analysis. lymphoma, BCL-2, cytogenetics, DEL 6q  相似文献   
4.
This series of articles, Managing Your Academic Career, presents ways to intentionally improve your teaching. This first article explains the concept of becoming an intention teacher. Subsequent articles will deal with strategies that are useful in clinical teaching, such as preparing students to value and use research in practice, and providing feedback to students in the clinical setting.  相似文献   
5.
A case of poisoning with 100 mg of oxybutynin in a 34-year-old female is reported. The main features were anticholinergic effects, including stupor, followed by disorientation and agitation on awakening, dilated pupils, dry skin and retention of urine. She had a sinus tachycardia which resolved 3 h after admission, and in addition ventricular ectopics and bigeminy which continued for a further 30 h. She recovered fully on symptomatic treatment alone.  相似文献   
6.

Background  

The aims of this study were to examine the extent to which higher intellectual abilities protect higher socio-economic groups from functional decline and to examine whether the contribution of intellectual abilities is independent of childhood deprivation and low birth weight and other socio-economic and developmental factors in early life.  相似文献   
7.
The initiation and growth of microscopic hepatocellular neoplasms in C57BL/6 mice, considered relatively resistant to hepatocarcinogenesis, was compared with that of the more responsive C3H and B6C3F1 (C57BL/6 x C3H) strains. Tumors were induced by giving male mice injections of diethylnitrosamine when they were 15 days old. During the first 18 weeks postinjection, the growth rates of neoplasms in the three strains were almost identical (doubling time of 2.1 to 2.5 weeks). However, after that time, only the growth rates of the C57BL/6 neoplasms slowed; between 30 and 42 weeks the doubling time had increased to 13 weeks. In addition, at all sacrifice times the number of neoplasms in the C3H strain was at least 2.5 times higher than in the C57BL/6 and B6C3F1 strains. These results suggest that the genetic determinant(s) for inhibited tumor growth (expressed only in C57BL/6 mice) are recessive to those for unimpeded tumor growth (expressed in C3H and B6C3F1 mice), while the determinant(s) for large numbers of tumors (expressed only in C3H mice) are recessive to those for small numbers of tumors (expressed in C57BL/6 and B6C3F1 mice). In addition to the interstrain differences in tumor growth, two other types of tumor growth heterogeneity were identified. First, in each of the three strains, the largest tumors were found to grow faster than the smaller tumors. This suggests that the very broad range in tumor size that is seen in this model results from the long-term differences in the growth rates of individual neoplasms. Second, we found that in microscopic hepatic neoplasms in B6C3F1 mice, the thymidine labeling indices were 2.3 times greater in the outer 50-microns shell (2 cells thick) than in the next deeper 50-micron layer cells. This suggests that even in these minute neoplasms, gradients in blood-borne oxygen, nutrients, or growth factors are responsible for heterogeneous growth.  相似文献   
8.
9.
10.
Defecography in multiple sclerosis patients with severe constipation   总被引:3,自引:0,他引:3  
Gill  KP; Chia  YW; Henry  MM; Shorvon  PJ 《Radiology》1994,191(2):553
  相似文献   
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