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   542篇
  免费   71篇
  国内免费   1篇
耳鼻咽喉   2篇
儿科学   6篇
妇产科学   8篇
基础医学   48篇
口腔科学   4篇
临床医学   43篇
内科学   162篇
皮肤病学   112篇
神经病学   51篇
特种医学   10篇
外科学   115篇
预防医学   26篇
眼科学   3篇
药学   6篇
肿瘤学   18篇
  2022年   6篇
  2021年   11篇
  2020年   14篇
  2019年   29篇
  2018年   29篇
  2017年   17篇
  2016年   21篇
  2015年   15篇
  2014年   23篇
  2013年   28篇
  2012年   38篇
  2011年   31篇
  2010年   15篇
  2009年   24篇
  2008年   43篇
  2007年   27篇
  2006年   32篇
  2005年   16篇
  2004年   21篇
  2003年   17篇
  2002年   23篇
  2001年   17篇
  2000年   15篇
  1999年   18篇
  1998年   7篇
  1997年   4篇
  1996年   6篇
  1995年   3篇
  1993年   5篇
  1992年   3篇
  1991年   7篇
  1990年   12篇
  1989年   2篇
  1988年   4篇
  1987年   6篇
  1986年   6篇
  1985年   3篇
  1984年   8篇
  1981年   1篇
  1979年   2篇
  1977年   1篇
  1976年   1篇
  1972年   1篇
  1971年   1篇
  1970年   1篇
排序方式: 共有614条查询结果,搜索用时 15 毫秒
1.
2.
Measurement of ultrasonographic parameters provides information concerning not only bone density but also bone architecture. We investigated the usefulness of ultrasonographic parameters and bone mineral density (BMD) to evaluate the probability of Colles' fracture. Two-hundred eighty-nine postmenopausal women (62.3 +/- 8.7 yr) with (n = 76) and without (n = 213) Colles' fracture were studied. BMD of lumbar spine and proximal femur was evaluated in all women by dual-energy X-ray absorptiometry (DXA) and speed of sound (SOS), broadband ultrasound attenuation (BUA), and stiffness in the calcaneus were measured by a Sahara ultrasonometer (Hologic). Patients suffering from Colles' fracture had lower values of BMD adjusted by height at the lumbar spine, L2-L4 (0.797 g/cm2 vs 0.860 g/cm2), femoral neck (0.685 g/cm2 vs 0.712 g/cm2 ), SOS (1518 m/sg vs 1525 m/sg), and stiffness (74.6 vs 77.7) (p < 0.05). Nevertheless, BUA values were similar in both groups. After stepwise logistic regression analysis, the area found under receiver operating characteristic (ROC) curves was 0.60 for L2L4 and 0.63 for a formula combining L2L4 and height. Our data suggest that patients suffering from Colles' fracture have lower values of BMD by DXA, SOS, and stiffness. However, the ability of these techniques to discriminate is low because the values for the area under ROC curve are 0.60 for L2-L4 and 0.63 for a formula derived of the combination of L2-L4 and height.  相似文献   
3.
Role of Natural Killer Cell Subsets in Cardiac Allograft Rejection   总被引:2,自引:0,他引:2  
To achieve donor-specific immune tolerance to allogeneic organ transplants, it is imperative to understand the cell types involved in acute allograft rejection. In wild-type mice, CD4(+) T cells are necessary and sufficient for acute rejection of cardiac allografts. However, when T-cell responses are suboptimal, such as in mice treated with costimulation-targeting agents or in CD28-deficient mice, and perhaps in transplanted patients taking immunosuppressive drugs, the participation of other lymphocytes such as CD8(+) T cells and NK1.1(+) cells becomes apparent. We found that host NK but not NKT cells were required for cardiac rejection. Ly49G2(+) NK cells suppressed rejection, whereas a subset of NK cells lacking inhibitory Ly49 receptors for donor MHC class I molecules was sufficient to promote rejection. Notably, rejection was independent of the activating receptors Ly49D and NKG2D. Finally, our experiments supported a mechanism by which NK cells promote expansion and effector function of alloreactive T cells. Thus, therapies aimed at specific subsets of NK cells may facilitate transplantation tolerance in settings of impaired T-cell function.  相似文献   
4.
The histopathological changes observed in the cutaneous rash of three patients who suffered the acute phase of HFV infection are described. In all three patients a perivascular and interstitial inflammatory infiltrate was present in the upper and mid-reticular dermis. In one biopsy isolated areas of epidermal necrosis were observed and in the two other biopsies a perifollicular inflammatory infiltrate was detected with perforation in one case. Furthermore, a periductal infiltrate was observed in one of these biopsies.  相似文献   
5.
6.
7.
8.
9.
10.
The objective of this study was to assess the efficacy and safety of amitriptyline as a treatment of FM. A comprehensive computerized search in Medline (Pubmed), EMBASE and The Cochrane Library was performed. Randomized controlled trials (RCTs) comparing amitriptyline vs placebo in adult patients suffering from FM were identified, the methodological quality was assessed and the results of the main outcomes were evaluated. Ten RCTs were identified. Large clinical variability and statistical heterogeneity precluded quantitative meta-analysis. Overall, the study quality was moderate to high. Amitriptyline 25 mg/day (six RCTs) demonstrated a therapeutic response compared with placebo in the domains of pain, sleep, fatigue and overall patient and investigator impression. This benefit was generally seen at 6-8 weeks of treatment but no effect was noted at 12 weeks. Amitriptyline 50 mg/day (four RCTs) did not demonstrate a therapeutic effect compared with placebo. Neither dose of amitriptyline had an effect on tender points count. No clear statements on adverse events with amitriptyline can be made due to inconsistencies in data among the studies. A definitive clinical recommendation regarding the efficacy of amitriptyline for FM symptoms cannot be made. There is some evidence to support the short-term efficacy of amitriptyline 25 mg/day in FM. There is no evidence to support the efficacy of amitriptyline at higher doses or for periods >8 weeks. More stringent RCTs with longer follow-up periods are required to determine the long-term efficacy and safety of the amitriptyline and define its role in the multidisciplinary management of FM.  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