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   100862篇
  免费   6163篇
  国内免费   438篇
耳鼻咽喉   1118篇
儿科学   2519篇
妇产科学   1798篇
基础医学   12504篇
口腔科学   1756篇
临床医学   10687篇
内科学   20306篇
皮肤病学   1339篇
神经病学   10097篇
特种医学   3907篇
外国民族医学   3篇
外科学   16359篇
综合类   1083篇
一般理论   131篇
预防医学   8269篇
眼科学   2087篇
药学   6510篇
中国医学   105篇
肿瘤学   6885篇
  2023年   563篇
  2022年   937篇
  2021年   2098篇
  2020年   1325篇
  2019年   2099篇
  2018年   2552篇
  2017年   1825篇
  2016年   1988篇
  2015年   2279篇
  2014年   3449篇
  2013年   4733篇
  2012年   7569篇
  2011年   7983篇
  2010年   4586篇
  2009年   4135篇
  2008年   7135篇
  2007年   7459篇
  2006年   7185篇
  2005年   6902篇
  2004年   6720篇
  2003年   6055篇
  2002年   5711篇
  2001年   849篇
  2000年   563篇
  1999年   894篇
  1998年   1221篇
  1997年   929篇
  1996年   752篇
  1995年   686篇
  1994年   590篇
  1993年   587篇
  1992年   455篇
  1991年   409篇
  1990年   333篇
  1989年   300篇
  1988年   282篇
  1987年   283篇
  1986年   244篇
  1985年   283篇
  1984年   308篇
  1983年   255篇
  1982年   337篇
  1981年   282篇
  1980年   222篇
  1979年   94篇
  1978年   130篇
  1977年   106篇
  1976年   82篇
  1975年   68篇
  1973年   72篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
62.
1. The effect of inflammation induced by lipopolysaccharide (LPS) injection on plasma follistatin (FS) concentrations was investigated. 2. Plasma FS and tumour necrosis factor-α concentrations increase following LPS administration in ewes. 3. The rise in FS is similar, but more sustained, to that previously observed after surgery. 4. These results indicate a possible functional link between FS, inflammation and the acute-phase response.  相似文献   
63.
Body pain and treatment response in late-life depression.   总被引:2,自引:0,他引:2  
OBJECTIVE: The authors investigated the influence of body pain on 1) time to treatment response and 2) suicidal ideation, in late-life depression. They hypothesized that higher levels of body pain would predict a longer time to and lower likelihood of response, and increased levels of suicidal ideation. METHODS: Subjects (N=187) were older adult outpatients (age > or =69 years), with current episodes of major depression, who were openly treated with paroxetine up to 40 mg daily and weekly interpersonal psychotherapy. Response was defined as 3 consecutive weeks of Hamilton Rating Scale for Depression at < or =10. Body pain was measured with the Bodily Pain Index of the SF-36 quality-of-life assessment. Authors used survival-analysis models on the responder sample to test the effect of body pain on response, after controlling for severity of depression. RESULTS: Overall response rate was 75.4%. Nonresponders reported more severe pain at baseline. After covarying for severity of baseline depression, no effect was found for physical pain on time-to-response or degree of suicidality. Bodily pain remained stable during acute treatment for responders, independent of depression response to combination psychotherapy and antidepressant treatment. CONCLUSIONS: Older adult patients with higher levels of physical pain can still respond to antidepressant treatment; however, reported bodily pain may be associated with a more difficult-to-treat depression.  相似文献   
64.
65.
66.
Despite recent advances in understanding the immunopathogenesis of oral lichen planus (LP), the initial triggers of lesion formation and the essential pathogenic pathways are unknown. It is therefore not surprising that the clinical management of oral LP poses considerable difficulties to the dermatologist and the oral physician. A consensus meeting was held in France in March 2003 to discuss the most controversial aspects of oral LP. Part 1 of the meeting report focuses on (1) the relationship between oral LP and viral infection with special emphasis on hepatitis C virus (HCV), and (2) oral LP pathogenesis, in particular the immune mechanisms resulting in lymphocyte infiltration and keratinocyte apoptosis. Part 2 focuses on patient management and therapeutic approaches and includes discussion on malignant transformation of oral LP.  相似文献   
67.
SUMMARY: Large simulations have become increasingly complex in many fields, tending to incorporate scale-dependent modeling and algorithms and wide-ranging physical influences. This scale of simulation sophistication has not yet been matched in neuroscience. The authors describe a framework aimed at enabling natural interaction with complex simulations: their configuration, initial conditions, monitoring, and analysis. The architecture is built on three cornerstone components: active probes, adaptive data capture, and visual interface. The resulting synthesis will enable interactive exploration of live simulations running on supercomputing platforms.  相似文献   
68.
This case report describes the rare phenomenon of encephalopathy associated with massive carcinoid tumor. Extensive investigation failed to reveal an obvious cause but a presumptive diagnosis of tryptophan deficiency was made and she was commenced on tryptophan dietary supplements. A rapid and complete response resulted. This case report discusses this unusual case and reviews the literature regarding carcinoid associated encephalopathy.  相似文献   
69.
We examined the time course effects of continuous PTH on cortical bone and mechanical properties. PTH increased cortical bone turnover and induced intracortical porosity with no deleterious effect on bone strength. Withdrawal of PTH increased maximum torque to failure and stiffness with no change in energy absorbed. INTRODUCTION: The skeletal response of cortical bone to parathyroid hormone (PTH) is complex and species dependent. Intermittent administration of PTH to rats increases periosteal and endocortical bone formation but has no known effects on intracortical bone turnover. The effects of continuous PTH on cortical bone are not clearly established. MATERIALS AND METHODS: Eighty-four 6-month-old female Sprague-Dawley rats were divided into three control, six PTH, and two PTH withdrawal (WD) groups. They were subcutaneously implanted with osmotic pumps loaded with vehicle or 40 microg/kg BW/day human PTH(1-34) for 1, 3, 5, 7, 14, and 28 days. After 7 days, PTH was withdrawn from two groups of animals for 7 (7d-PTH/7d-WD) and 21 days (7d-PTH/21d-WD). Histomorphometry was performed on periosteal and endocortical surfaces of the tibial diaphysis in all groups. microCT of tibias and mechanical testing by torsion of femora were performed on 28d-PTH and 7d-PTH/21d-WD animals. RESULTS AND CONCLUSIONS: Continuous PTH increased periosteal and endocortical bone formation, endocortical osteoclast perimeter, and cortical porosity in a time-dependent manner, but did not change the mechanical properties of the femur, possibly because of addition of new bone onto periosteal and endocortical surfaces. Additionally, withdrawal of PTH restored normal cortical porosity and increased maximum torque to failure and stiffness. We conclude that continuous administration of PTH increased cortical porosity in rats without having a detrimental effect on bone mechanical properties.  相似文献   
70.
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