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   2745篇
  免费   166篇
  国内免费   14篇
耳鼻咽喉   52篇
儿科学   199篇
妇产科学   46篇
基础医学   281篇
口腔科学   59篇
临床医学   289篇
内科学   673篇
皮肤病学   39篇
神经病学   156篇
特种医学   270篇
外科学   402篇
综合类   41篇
预防医学   105篇
眼科学   35篇
药学   133篇
  1篇
中国医学   1篇
肿瘤学   143篇
  2023年   6篇
  2022年   6篇
  2021年   41篇
  2020年   33篇
  2019年   45篇
  2018年   75篇
  2017年   38篇
  2016年   37篇
  2015年   52篇
  2014年   63篇
  2013年   78篇
  2012年   124篇
  2011年   136篇
  2010年   109篇
  2009年   97篇
  2008年   144篇
  2007年   120篇
  2006年   110篇
  2005年   113篇
  2004年   110篇
  2003年   106篇
  2002年   105篇
  2001年   68篇
  2000年   74篇
  1999年   80篇
  1998年   96篇
  1997年   102篇
  1996年   103篇
  1995年   71篇
  1994年   61篇
  1993年   51篇
  1992年   36篇
  1991年   38篇
  1990年   29篇
  1989年   43篇
  1988年   46篇
  1987年   44篇
  1986年   26篇
  1985年   38篇
  1984年   28篇
  1983年   25篇
  1982年   23篇
  1981年   22篇
  1980年   10篇
  1979年   6篇
  1978年   7篇
  1977年   9篇
  1976年   9篇
  1975年   8篇
  1970年   4篇
排序方式: 共有2925条查询结果,搜索用时 187 毫秒
1.
2.
Familial 46,XX gonadal dysgenesis   总被引:1,自引:0,他引:1  
Two sisters, ages 18 and 25, presented with primary amenorrhea and underwent clinical, hormonal, cytogenetic, and pathologic evaluation. Both were of normal stature and lacking of somatic stigmata. Both patients had normal 46,XX karyotype on peripheral blood. Streak gonads were seen in both patients and a rather scanty number of primordial follicles was found in one patient. FSH, LH, and urinary estrogens were consistent with streak gonad syndrome. Autosomal recessive inheritance has been suggested in familial aggregates with XX gonadal dysgenesis.  相似文献   
3.
To evaluate the effects of irradiation on heterotopically placed vascularized knee isografts, a single dose of 10 Gy of total-body irradiation was given to Lewis donor rats. Irradiation was delivered either 2 or 6 days prior to harvesting or subsequent transplantation, and evaluated at 1, 2, and 4 weeks after grafting. Irradiation caused endothelial depopulation of the graft artery, although vascular pedicle patency was maintained throughout the study. Bone graft viability and mineralization were normal. Dramatic changes in the bone marrow were seen that included an increase of its fat content (P less than 0.001), and a concomitant decrease in bone marrow-derived immunocompetent cells. These changes were more prominent in recipients of grafts from day -6 irradiated donor rats. Total-body irradiation did not prejudice the use of vascularized bone grafts, and exhibited an associated immunosuppresant effect over the vascular endothelium and bone marrow. This may be a further rational conditioning procedure to avoid recipient manipulation in vascularized bone allotransplantation.  相似文献   
4.

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   
5.
6.
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   
7.
Previous reports in the literature have described correlation of increasing repeat length with severity of the phenotype, in Kennedy syndrome. We describe male siblings with different repeat lengths, with lack of expression of the phenotype in the sibling with the longer repeat length. The phenotype was identical to motor neurone disease. There is variability of expression in Kennedy syndrome and repeat length even in siblings cannot be taken as a conclusive indicator of severity. CAG repeat length cannot be used to predict the natural history of Kennedy disease. The diagnosis of Kennedy syndrome should be considered in male patients presenting with atypical motor neurone disease.  相似文献   
8.
9.
SUMMARY The interferons are natural glycoproteins secreted in response to various stimuli, including viral infection. They have antiviral, antiproliferative and immunomodulatory effects on different target cell populations. Since recombinant human interferons have become available, they have been tested in a wide range of malignancies. They are well established in the treatment of hairy cell leukaemia, chronic myelogenous leukaemia and multiple myeloma. Although they have documented activity against lymphoma, melanoma, renal cell cancer and carcinoid tumours, their role in the treatment of these tumours is less clear. In the common solid tumours, such as lung cancer and colorectal cancer, the use of interferons remains experimental. Here we will summarise their practice applications in oncology, using randomised studies where available to establish their place in multi-modality treatment. We will not discuss their use as antiviral or immunomodulating agents in viral and autoimmune diseases, multiple sclerosis or after organ transplantation.  相似文献   
10.
Chronic low back pain: comparison of bone SPECT with radiography and CT   总被引:1,自引:0,他引:1  
Ryan  PJ; Evans  PA; Gibson  T; Fogelman  I 《Radiology》1992,182(3):849
  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