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   1378篇
  免费   77篇
  国内免费   2篇
耳鼻咽喉   6篇
儿科学   23篇
妇产科学   20篇
基础医学   186篇
口腔科学   7篇
临床医学   192篇
内科学   250篇
皮肤病学   4篇
神经病学   93篇
特种医学   17篇
外科学   252篇
综合类   12篇
一般理论   1篇
预防医学   145篇
眼科学   3篇
药学   148篇
中国医学   1篇
肿瘤学   97篇
  2023年   7篇
  2022年   8篇
  2021年   25篇
  2020年   18篇
  2019年   25篇
  2018年   34篇
  2017年   19篇
  2016年   20篇
  2015年   32篇
  2014年   66篇
  2013年   83篇
  2012年   137篇
  2011年   118篇
  2010年   60篇
  2009年   38篇
  2008年   70篇
  2007年   87篇
  2006年   57篇
  2005年   54篇
  2004年   53篇
  2003年   36篇
  2002年   64篇
  2001年   16篇
  2000年   28篇
  1999年   22篇
  1998年   14篇
  1997年   12篇
  1996年   8篇
  1995年   8篇
  1994年   7篇
  1992年   12篇
  1991年   14篇
  1990年   10篇
  1989年   12篇
  1988年   16篇
  1987年   6篇
  1986年   12篇
  1985年   14篇
  1984年   11篇
  1983年   15篇
  1982年   13篇
  1981年   7篇
  1979年   11篇
  1978年   11篇
  1977年   6篇
  1976年   6篇
  1974年   7篇
  1972年   7篇
  1971年   12篇
  1969年   5篇
排序方式: 共有1457条查询结果,搜索用时 15 毫秒
41.
42.

Background

Robot-assisted radical prostatectomy (RARP) remains controversial, and no improvement in cancer control outcomes has been demonstrated over open radical prostatectomy (ORP).

Objective

To examine population-based, comparative effectiveness of RARP versus ORP pertaining surgical margin status and use of additional cancer therapy.

Design, setting, and participants

This was a retrospective observational study of 5556 RARP and 7878 ORP cases from 2004 to 2009 from Surveillance Epidemiology and End Results–Medicare linked data.

Intervention

RARP versus ORP.

Outcome measurements and statistical analysis

Propensity-based analyses were performed to minimize treatment selection biases. Generalized linear regression models were computed for comparison of RP surgical margin status and use of additional cancer therapy (radiation therapy [RT] or androgen deprivation therapy [ADT]) by surgical approach.

Results and limitations

In the propensity-adjusted analysis, RARP was associated with fewer positive surgical margins (13.6% vs 18.3%; odds ratio [OR]: 0.70; 95% confidence interval [CI], 0.66–0.75), largely because of fewer RARP positive margins for intermediate-risk (15.0% vs 21.0%; OR: 0.66; 95% CI, 0.59–0.75) and high-risk (15.1% vs 20.6%; OR: 0.70; 95% CI, 0.63–0.77) disease. In addition, RARP was associated with less use of additional cancer therapy within 6 mo (4.5% vs 6.2%; OR: 0.75; 95% CI, 0.69–0.81), 12 mo (OR: 0.73; 95% CI, 0.62–0.86), and 24 mo (OR: 0.67; 95% CI, 0.57–0.78) of surgery. Limitations include the retrospective nature of the study and the absence of prostate-specific antigen levels to determine biochemical recurrence.

Conclusions

RARP is associated with improved surgical margin status relative to ORP for intermediate- and high-risk disease and less use of postprostatectomy ADT and RT. This has important implications for quality of life, health care delivery, and costs.

Patient summary

Robot-assisted radical prostatectomy (RP) versus open RP is associated with fewer positive margins and better early cancer control because of less use of additional androgen deprivation and radiation therapy within 2 yr of surgery.  相似文献   
43.
44.
45.

Background

Excess body weight is a risk factor for obstructive sleep apnoea (OSA). The aim of the systematic review was to establish whether weight loss via lifestyle interventions such as diet and exercise are useful in the treatment of OSA.

Methods

A literature search was conducted between 1980 and February 2012. Systematic reviews and randomised controlled trials (RCTs) with participants who had OSA, were overweight or obese, and who had undergone lifestyle interventions with the aim of improving sleep apnoea were included. Meta analyses were conducted for a subset of RCTs with appropriate data.

Results

Two systematic reviews and eight RCTs were included. Meta-analyses were conducted for four RCTs comparing intensive lifestyle interventions to a control. The overall weighted mean differences for weight change, change in apnoea -hypopnoea index (AHI) and change in oxygen desaturation index of ≥4% were as follows: −13.76 kg (95% confidence interval (CI) −19.21, −-8.32), −16.09 (95% CI −25.64, −6.54) and −14.18 (95% CI −24.23, −4.13), respectively. Although high heterogeneity within the meta analyses, all studies favoured the interventions. Long-term follow-up data from three RCTs suggest that improvements in weight and AHI are maintained for up to 60 months.

Conclusions

Intensive lifestyle interventions are effective in the treatment of OSA, resulting in significant weight loss and a reduction in sleep apnoea severity. Weight loss via intensive lifestyle interventions could be encouraged as a treatment for mild to moderate OSA.  相似文献   
46.
47.
Using cultured human osteoblast-like cells, we studied the effects of tumor necrosis factor (TNF) and recombinant human γ-interferon (γ-IFN) on osteoblast growth and function, and demonstrated that TNF stimulated bone cell proliferation and prostaglandin production while inhibiting 1,25-(OH)2D3—stimulated alkaline phosphatase activity and osteocalcin release. In contrast, γ-IFN inhibited proliferation and stimulated alkaline phosphatase activity of the cells, while inhibiting 1,25-(OH)2D3—stimulated osteocalcin production and having variable effects on the release of prostaglandins, depending on the presence of other factors. Our results suggest that TNF and γ-IFN can act directly on bone-forming cells to affect both their proliferation and their differentiated function, and that changes in the ability of cells to produce these factors in disease states may contribute to alterations in the integrity of connective tissue matrices.  相似文献   
48.
49.
In this case study, we describe a method that has potential to provide systematic support for public health information management. Public health agencies depend on specialized information that travels throughout an organization via communication networks among employees. Interactions that occur within these networks are poorly understood and are generally unmanaged. We applied organizational network analysis, a method for studying communication networks, to assess the method's utility to support decision making for public health managers, and to determine what links existed between information use and agency processes. Data on communication links among a health department's staff was obtained via survey with a 93% response rate, and analyzed using Organizational Risk Analyzer (ORA) software. The findings described the structure of information flow in the department's communication networks. The analysis succeeded in providing insights into organizational processes which informed public health managers' strategies to address problems and to take advantage of network strengths.  相似文献   
50.
Metabolic adaptation is considered an emerging hallmark of cancer, whereby cancer cells exhibit high rates of glucose consumption with consequent lactate production. To ensure rapid efflux of lactate, most cancer cells express high levels of monocarboxylate transporters (MCTs), which therefore may constitute suitable therapeutic targets. The impact of MCT inhibition, along with the clinical impact of altered cellular metabolism during prostate cancer (PCa) initiation and progression, has not been described. Using a large cohort of human prostate tissues of different grades, in silico data, in vitro and ex vivo studies, we demonstrate the metabolic heterogeneity of PCa and its clinical relevance. We show an increased glycolytic phenotype in advanced stages of PCa and its correlation with poor prognosis. Finally, we present evidence supporting MCTs as suitable targets in PCa, affecting not only cancer cell proliferation and survival but also the expression of a number of hypoxia‐inducible factor target genes associated with poor prognosis. Herein, we suggest that patients with highly glycolytic tumours have poorer outcome, supporting the notion of targeting glycolytic tumour cells in prostate cancer through the use of MCT inhibitors. © 2015 Authors. Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.  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