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   930篇
  免费   92篇
  国内免费   6篇
耳鼻咽喉   8篇
儿科学   18篇
妇产科学   16篇
基础医学   111篇
口腔科学   17篇
临床医学   91篇
内科学   192篇
皮肤病学   3篇
神经病学   57篇
特种医学   241篇
外科学   99篇
综合类   27篇
预防医学   35篇
眼科学   11篇
药学   48篇
中国医学   1篇
肿瘤学   53篇
  2020年   7篇
  2019年   7篇
  2018年   6篇
  2013年   12篇
  2012年   14篇
  2011年   24篇
  2010年   21篇
  2009年   12篇
  2008年   16篇
  2007年   35篇
  2006年   19篇
  2005年   31篇
  2004年   27篇
  2003年   24篇
  2002年   23篇
  2001年   27篇
  2000年   23篇
  1999年   18篇
  1998年   24篇
  1997年   28篇
  1996年   19篇
  1995年   21篇
  1994年   32篇
  1993年   20篇
  1992年   23篇
  1991年   18篇
  1990年   30篇
  1989年   36篇
  1988年   37篇
  1987年   35篇
  1986年   24篇
  1985年   38篇
  1984年   30篇
  1983年   26篇
  1982年   21篇
  1981年   22篇
  1980年   18篇
  1979年   15篇
  1978年   17篇
  1977年   15篇
  1976年   15篇
  1975年   5篇
  1974年   15篇
  1973年   9篇
  1972年   5篇
  1970年   6篇
  1969年   6篇
  1968年   6篇
  1967年   7篇
  1966年   7篇
排序方式: 共有1028条查询结果,搜索用时 15 毫秒
1.

Background  

Bortezomib, a proteasome-specific inhibitor, has emerged as a promising cancer therapeutic agent. However, development of resistance to bortezomib may pose a challenge to effective anticancer therapy. Therefore, characterization of cellular mechanisms involved in bortezomib resistance and development of effective strategies to overcome this resistance represent important steps in the advancement of bortezomib-mediated cancer therapy.  相似文献   
2.
3.
To investigate indirectly the central neurotransmitter mechanisms of D,L-fenfluramine-induced hormone release, prolactin, adrenocorticotropic hormone, cortisol, growth hormone, 3-methoxy-4-hydroxyphenylglycol (MHPG), homovanillic acid (HVA), and 5-hydroxyindoleacetic acid (5HIAA) responses to D,L-fenfluramine (60 mg, oral) were examined in a single-blind, placebo-controlled trial in 14 normal subjects. As compared with placebo, D,L-fenfluramine significantly increased both prolactin and cortisol. There was a significant correlation between the cortisol and prolactin responses. HVA levels were also significantly increased, but there were no changes in MHPG or 5HIAA. The elevation in HVA significantly correlated with increases in both prolactin and cortisol. These findings are consistent with recent animal studies suggesting that D,L-fenfluramine-induced prolactin and cortisol release may be mediated, at least in part, by catecholaminergic systems.  相似文献   
4.
5.
Normal and diseased isolated lungs: high-resolution CT   总被引:8,自引:0,他引:8  
  相似文献   
6.
M Smythe 《Pharmacotherapy》1992,12(2):132-143
The patient-activated analgesic system was introduced in 1968. Early trials, although uncontrolled, supported the safety and efficacy of patient-controlled analgesia (PCA) in several kinds of pain, such as that relating to surgery, cancer, trauma, and obstetric procedures. In the past decade, prospective, randomized trials have reported several advantages of PCA over conventional analgesia in the early postoperative period. Although not supported by all controlled trials, they include improved pain relief, less sedation, lower level of narcotic consumption, fewer postoperative complications, greater patient satisfaction, and improved pulmonary function. Preliminary results in the management of chronic pain indicate that PCA can lead to significant lifestyle improvements in ambulatory patients with cancer. The most significant, although infrequent, adverse effect is respiratory depression, the majority of cases occurring in patients predisposed secondary to concomitant illness or as a result of human error. The clinical use of PCA will likely see a significant increase among persons with cancer, and an increase in epidural administration. The cost benefit of PCA has yet to be assessed in inpatient and outpatient settings.  相似文献   
7.
BACKGROUND: Inflammatory bowel disease is associated with increased mucosal release of eicosanoids. Among these, thromboxane A2 has been proposed as a possible inflammatory mediator; its suppression may be a useful therapeutic option. METHODS: Using a tissue incubation technique, we compared release of immunoreactive thromboxane B2 by colonic biopsies from patients with ulcerative colitis, Crohn's disease and controls, and assessed the inhibitory effect of picotamide, a thromboxane synthesis inhibitor-receptor antagonist, which has been widely used in Italy for management of ischaemic heart and cerebrovascular disease. RESULTS: Increased amounts of thromboxane B2 were released from biopsies from patients with active ulcerative colitis (median 238 pg/20 min/mg wet weight (interquartile range 147- 325), n = 12) and active Crohn's disease (252 (174-450), 6) compared with those from patients with quiescent ulcerative colitis (95 (61- 140), 12) or Crohn's disease (105 (57-201), 13), or controls (136 (64- 206), 8). Incubation with picotamide at concentrations between 100 microM and 1 mM reduced thromboxane B2 release (IC50 890 microM). CONCLUSION: Since increased thromboxane A2 production may have pathogenetic importance, thromboxane synthesis inhibitor-receptor antagonists such as picotamide merit therapeutic trial in the management of inflammatory bowel disease.  相似文献   
8.
9.
10.
Hydrosalpinges adversely affect markers of endometrial receptivity   总被引:22,自引:10,他引:22  
While in-vitro fertilization (IVF) was initially developed in women with tubal factor infertility, recent clinical studies have suggested that the presence of hydrosalpinges lowers implantation and pregnancy rates. We postulated that these hydrosalpinges cause impaired endometrial receptivity. A total of 103 women with hydrosalpinges were prospectively evaluated, and compared with 55 infertile and 44 fertile controls. All women had endometrial biopsies during the window of implantation, analysed by conventional histological criteria, and also stained for three integrin markers of endometrial receptivity (alpha1beta1, alpha4beta1 and alpha vbeta3). Women with hydrosalpinges (cases) expressed significantly less of the alpha vbeta3 integrin compared with controls. There was no difference in expression of alpha1beta1 or alpha4beta1 among groups. A significantly greater number of cases had out of phase histology and missing alpha vbeta3 (type I defects) and absent integrin expression despite normal histological maturation (type II) defects, compared with controls. Of 20 women with impaired endometrial receptivity who were also biopsied after hydrosalpinx surgery, 70% demonstrated increased alpha vbeta3 expression. Seventy-seven percent of type I and 57% of type II defects were corrected postoperatively. Using markers of endometrial receptivity, this study demonstrates that inflammatory hydrosalpinges have an adverse effect on endometrial receptivity, which in some cases may be overcome by surgical treatment of the hydrosalpinx.   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