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   1611篇
  免费   103篇
  国内免费   3篇
耳鼻咽喉   8篇
儿科学   27篇
妇产科学   13篇
基础医学   258篇
口腔科学   45篇
临床医学   145篇
内科学   345篇
皮肤病学   34篇
神经病学   171篇
特种医学   67篇
外科学   208篇
综合类   5篇
预防医学   117篇
眼科学   8篇
药学   101篇
中国医学   5篇
肿瘤学   160篇
  2023年   8篇
  2022年   14篇
  2021年   45篇
  2020年   20篇
  2019年   27篇
  2018年   34篇
  2017年   29篇
  2016年   27篇
  2015年   40篇
  2014年   37篇
  2013年   63篇
  2012年   82篇
  2011年   88篇
  2010年   72篇
  2009年   42篇
  2008年   69篇
  2007年   66篇
  2006年   80篇
  2005年   87篇
  2004年   74篇
  2003年   65篇
  2002年   61篇
  2001年   45篇
  2000年   61篇
  1999年   53篇
  1998年   18篇
  1997年   22篇
  1996年   18篇
  1995年   15篇
  1994年   7篇
  1993年   11篇
  1992年   42篇
  1991年   25篇
  1990年   27篇
  1989年   27篇
  1988年   19篇
  1987年   24篇
  1986年   21篇
  1985年   19篇
  1984年   13篇
  1983年   11篇
  1982年   7篇
  1980年   7篇
  1979年   10篇
  1978年   9篇
  1977年   10篇
  1975年   6篇
  1974年   10篇
  1972年   7篇
  1969年   10篇
排序方式: 共有1717条查询结果,搜索用时 15 毫秒
41.
OBJECTIVE: To evaluate the applicability of the WHO densitometric criteria for the diagnosis of spinal osteoporosis in men and to compare it with women with vertebral fractures, as well as to analyze the role of vertebral dimensions in the development of spinal fractures. METHODS: For these purposes we analyzed, using DXA, vertebral projected area and lumbar bone mineral density (BMD), as well as T and Z-scores in lumbar spine in a cohort of 66946 individuals; 2556 of these subjects had one or more atraumatic vertebral fracture (396 men and 2160 postmenopausal women). RESULTS: Men and women with fractures showed significantly lower mean BMD, T-score and Z-score values than individuals without fractures while vertebral dimensions were similar in both groups of patients. When comparing men and women with vertebral fractures, the former showed a significantly greater projected area (46.89+/-5.5 vs. 39.13+/-4.6 cm(2) p<0.001) and lumbar BMD (0.991+/- 0.21 vs. 0.938+/- t0.19 g/cm(2) p<0.001). However, the median lumbar T-score values were similar for both sexes (-2.3 in women vs. -2.2 in men; p: NS). In addition, a similar percentage of men and women with vertebral fractures showed T-score values <-2.5 in the lumbar spine (44% vs. 46%, p=NS). CONCLUSION: We conclude that although men with vertebral fractures have greater vertebral dimensions and BMD than women, the lumbar T-scores are similar. Therefore, it seems reasonable to adopt the same T-score values for the diagnosis of osteoporosis in men and women.  相似文献   
42.
43.
44.
45.
46.
Angiographic contrast media are known to induce alterations in cardiovascular dynamics which may result in acute pulmonary edema. The risk of pulmonary edema was previously shown to be negatively correlated to the level of colloid oncotic pressure (COP). It was also shown that the gradient between COP and left ventricular end-diastolic pressure (LVEDP) represents a better predictor of pulmonary edema than does LVEDP alone. The present report evaluates the effects of a bolus injection of contrast media on those pressures, as predisposing factors for pulmonary edema.Our data are based on 15 unselected patients admitted for coronary angiography. The plasma volume increased by 16.5% (2,903 to 3,384 ml.) at two minutes after injection of a 50 c.c. bolus of meglumine diatrizoate (Renographin 76%) and had returned towards normal at 30 minutes. In parallel the COP decreased from 23.4 ± 2.4 to 19.6 ± 2.3 mm. Hg (P < 0.001) to return the 22.7 ± 2.6. The COP-LVEDP gradient decreased by 8.7 mm. Hg (8.4 to ?0.3, P < 0.001). Such a gradient was well within the danger zone of pulmonary edema. These findings further clarify the mechanisms of pulmonary edema induced by contrast media.  相似文献   
47.
To assess the place of allogeneic hematopoietic stem cell transplantation (HSCT) in the advanced stage of acute myeloid leukemia (AML), we retrospectively analyzed 379 consecutive patients who underwent allogeneic HSCT for advanced AML. The median follow-up of the entire cohort was 7.5 years. Sixty-nine patients (18%) were transplanted with primary resistant disease. Three hundred and ten (82%) were relapsed patients, 94 (30%) of whom were in untreated relapse, 67 (22%) in refractory relapse and 149 (48%) in 2nd or 3rd complete remission at time of transplantation. The 5-year probabilities of overall survival (OS), disease-free survival (DFS), and transplant-related mortality (TRM) were 22 +/- 4%, 20 +/- 4%, 45 +/- 6%, respectively. In multivariate analysis, we demonstrated the favorable impact on OS, DFS and TRM of two factors over which we have no control (age <15 years, complete remission achievement) and three factors over which we have some control (female donor, acute and chronic graft-versus-host disease). The results of this study suggest that the graft-versus-leukemia effect is important in advanced AML and that new HSCT modalities are needed for some patients with this indication.  相似文献   
48.
49.
50.
This cross-sectional observational study aimed to explore the relationship between B cell count and ultrasound (US)-detected synovitis, in patients with rheumatoid arthritis treated with rituximab. Thirty-seven consecutive RA patients treated with RTX were recruited for the study. The patients underwent clinical [i.e., Disease Activity Score 28 joints (DAS28)], laboratory, and US assessment of 12 joints. Each joint was semiquantitatively (0–3) scored on B-mode and power Doppler mode. The scores were summed, and a global index was created for BM (BMS) and PD scores (PDI) synovitis. BM subclinical synovitis was evident in all patients, with PD synovial signal detected in 16 patients (43.2 %). No correlation was found between DAS28 and US scores. B cells were detected in 27 (72.9 %) patients, but there was no association in the mean B cell count and disease activity as measured by DAS28 (DAS28 < 2.6 = 34.53, DAS28 > 2.6 = 49.45, p = 0.52) and PDI score (PDI < 1 = 49.48, PDI > 1 = 35.44, p = 0.54). There was no correlation between the B cell count and DAS28, BMS, and PDI (r = 0.020, p = 0.907; r = ?0.151, p = 0.371; r = ?0.099, p = 0.558, respectively). In RTX-treated RA patients, no relationship could be established between US-detected synovitis and peripheral blood B cell count.  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