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   1067篇
  免费   79篇
  国内免费   9篇
耳鼻咽喉   4篇
儿科学   57篇
妇产科学   9篇
基础医学   101篇
口腔科学   51篇
临床医学   184篇
内科学   211篇
皮肤病学   13篇
神经病学   36篇
特种医学   244篇
外科学   62篇
综合类   22篇
预防医学   41篇
眼科学   9篇
药学   63篇
中国医学   5篇
肿瘤学   43篇
  2024年   3篇
  2023年   9篇
  2022年   2篇
  2021年   11篇
  2020年   7篇
  2019年   7篇
  2018年   24篇
  2017年   14篇
  2016年   21篇
  2015年   25篇
  2014年   31篇
  2013年   26篇
  2012年   26篇
  2011年   22篇
  2010年   40篇
  2009年   59篇
  2008年   32篇
  2007年   15篇
  2006年   29篇
  2005年   13篇
  2004年   13篇
  2003年   23篇
  2002年   17篇
  2001年   20篇
  2000年   10篇
  1999年   19篇
  1998年   49篇
  1997年   52篇
  1996年   65篇
  1995年   50篇
  1994年   44篇
  1993年   50篇
  1992年   16篇
  1991年   9篇
  1990年   15篇
  1989年   35篇
  1988年   31篇
  1987年   32篇
  1986年   35篇
  1985年   25篇
  1984年   15篇
  1983年   12篇
  1982年   23篇
  1981年   15篇
  1980年   9篇
  1979年   7篇
  1978年   6篇
  1977年   13篇
  1976年   12篇
  1975年   14篇
排序方式: 共有1155条查询结果,搜索用时 0 毫秒
41.
42.
43.
44.
Purpose: The present observational study compares in‐hospital and 12‐month clinical outcomes in elderly patients with unprotected left main coronary artery disease treated either with coronary artery bypass grafting or drug‐eluting stent. Methods: From January 2004 to December 2007, 211 patients (pts) with unprotected left main coronary artery (ULMCA) stenosis, aged 75 or older, underwent coronary revascularization either with coronary artery bypass graft (CABG) (106 pts) or drug‐eluting stent (DES) (105 pts). The decision to treat with CABG or percutaneous coronary intervention (PCI) was dependent on the patient's and the physician's choice. The occurrence of major adverse cardiac or cerebrovascular events (MACCE: death, nonfatal myocardial infarction, or stroke) and revascularizations was recorded after 1 year of follow‐up. A multivariate logistic regression analysis was performed using a propensity score method to take potential baseline differences between groups into account. Results: In‐hospital MACCE rates were 5.7% and 3.8% in the CABG and PCI groups, respectively (P = 0.748). After 1 year of follow‐up, these rates were, respectively, 13.9% and 14.9% (P = 0.841), and rates for target vessel revascularization at 12 months were 1.0% and 13.9% (P < 0.001). The PCI group was significantly associated with older age, dyslipidemia, history of cancer, high Euroscore, elevated creatininemia, single‐vessel disease, fewer chronic occlusions of the left anterior descending artery, and more LMCA stenosis ≥70%. The multivariate logistic regression analysis was adjusted for age, diabetes, left ventricular ejection fraction, Euroscore, and plasma creatininemia and stratified on the score of propensity to be treated with PCI. In the subgroup below median propensity score, the adjusted odds ratio for 1‐year MACCE was OR = 0.91 (95% confidence interval: 0.14 to 5.98; P = 0.924) whereas OR was 0.16 (0.04–0.69; P = 0.013) in the subgroup above median propensity score. Conclusions: In patients with a high probability of being treated with PCI (older age, high Euroscore, high creatininemia, single‐vessel disease, …), the 1‐year risk of MACCE was significantly lower in PCI‐ than in CABG‐treated subjects. No significant difference was found in other cases.  相似文献   
45.
46.
47.
Natural killer (NK)-like T cells are major histocompatibility complex- unrestricted cytotoxic T cells that are surface CD3-positive, express NK-cell antigens, and rearrange their T-cell receptor. Most neoplasms arising from this T-cell subpopulation have been a chronic lymphoproliferative disease referred to as T-large granular lymphocyte (LGL) leukemia. Only 10 NK-like T-cell lymphomas have been described in detail previously; this study presents the clinicopathologic features of six others and distinguishes these lymphomas from T-LGL leukemia. All patients presented with B-symptoms and often had marked hepatosplenomegaly without significant peripheral lymphadenopathy. Four of the six patients were immunosuppressed. All had CD3, CD8, CD56- positive tumors, presumably of hepatosplenic (n = 3), intestinal (n = 1), pulmonary (n = 1), or nodal (n = 1) origin. Three patients had lymphomatous bone marrow infiltrates, and four had peripheral blood involvement by neoplastic large lymphocytes, some of which had a blastic appearance or resembled virocytes. Azurophilic granules, ultrastructurally corresponding to cytoplasmic dense core and/or double density granules, were seen in all cases. T-cell clonality was shown in five tumors by Southern blot analysis, and three had abnormal karyotypes. Two untreated patients died 20 days after presentation, and three patients who received combination chemotherapy died within 5 months of presentation. One patient remains in complete remission 22 months after treatment. These findings suggest NK-like T-cell lymphomas are aggressive, are clinicopathologically distinct from T-LGL leukemia, and should be in the differential diagnosis of extranodal T-cell lymphoproliferations, including those in immunosuppressed patients. Furthermore, the LGL morphology, phenotype, and tissue distribution of some NK-like T-cell lymphomas suggest they arise from thymic- independent T cells of the hepatic sinusoids and intestinal mucosa.  相似文献   
48.
49.
50.
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