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   1848篇
  免费   188篇
  国内免费   96篇
耳鼻咽喉   37篇
儿科学   60篇
妇产科学   15篇
基础医学   222篇
口腔科学   48篇
临床医学   257篇
内科学   473篇
皮肤病学   25篇
神经病学   84篇
特种医学   194篇
外科学   92篇
综合类   57篇
一般理论   1篇
预防医学   226篇
眼科学   25篇
药学   241篇
中国医学   13篇
肿瘤学   62篇
  2023年   8篇
  2021年   22篇
  2019年   19篇
  2018年   20篇
  2017年   18篇
  2016年   21篇
  2015年   21篇
  2014年   24篇
  2013年   52篇
  2012年   53篇
  2011年   60篇
  2010年   62篇
  2009年   51篇
  2008年   75篇
  2007年   155篇
  2006年   112篇
  2005年   101篇
  2004年   84篇
  2003年   86篇
  2002年   77篇
  2001年   79篇
  2000年   78篇
  1999年   66篇
  1998年   56篇
  1997年   48篇
  1996年   46篇
  1995年   42篇
  1994年   35篇
  1993年   40篇
  1992年   25篇
  1991年   25篇
  1990年   33篇
  1989年   46篇
  1988年   41篇
  1987年   33篇
  1986年   39篇
  1985年   32篇
  1984年   28篇
  1983年   20篇
  1982年   16篇
  1981年   12篇
  1980年   16篇
  1979年   22篇
  1978年   14篇
  1977年   18篇
  1974年   9篇
  1973年   8篇
  1972年   8篇
  1971年   9篇
  1969年   9篇
排序方式: 共有2132条查询结果,搜索用时 46 毫秒
31.
Oxidative stress caused by reactive oxygen species is proposed to cause age related muscle wasting (sarcopenia). Reversible oxidation of protein thiols by reactive oxygen species can affect protein function, so we evaluated whether muscle wasting in normal aging was associated with a pervasive increase in reversible oxidation of protein thiols or with an increase in irreversible oxidative damage to macromolecules. In gastrocnemius muscles of C57BL/6J female mice aged 3, 15, 24, 27, and 29 months there was no age related increase in protein thiol oxidation. In contrast, there was a significant correlation (R 2 = 0.698) between increasing protein carbonylation, a measure of irreversible oxidative damage to proteins, and loss of mass of gastrocnemius muscles in aging female mice. In addition, there was an age-related increase in lipofuscin content, an aggregate of oxidised proteins and lipids, in quadriceps limb muscles in aging female mice. However, there was no evidence of an age-related increase in malondialdehyde or F2-isoprostanes levels, which are measures of oxidative damage to lipids, in gastrocnemius muscles. In summary, this study does not support the hypothesis that a pervasive increase in protein thiol oxidation is a contributing factor to sarcopenia. Instead, the data are consistent with an aging theory which proposes that molecular damage to macromolecules leads to the structural and functional disorders associated with aging.  相似文献   
32.
33.
34.
35.
Croft AM  Palmer JV 《Lancet》2012,379(9818):799-800; author reply 800-1
  相似文献   
36.
37.
We performed a meta-analysis of 3 genome-wide association studies to identify additional common variants influencing chronic lymphocytic leukemia (CLL) risk. The discovery phase was composed of genome-wide association study data from 1121 cases and 3745 controls. Replication analysis was performed in 861 cases and 2033 controls. We identified a novel CLL risk locus at 6p21.33 (rs210142; intronic to the BAK1 gene, BCL2 antagonist killer 1; P = 9.47 × 10(-16)). A strong relationship between risk genotype and reduced BAK1 expression was shown in lymphoblastoid cell lines. This finding provides additional support for polygenic inheritance to CLL and provides further insight into the biologic basis of disease development.  相似文献   
38.
Abstract: The prevalence of Parkinson’s disease (PD) is expected to double over the next 20 years owing to the increase in life expectancy. This progressive disease has several implications relating to oral health, and many are manageable with proper awareness and knowledge about the disease. This article reviews the epidemiology, pathophysiology, and characteristics of PD, as well as the treatments and oral health considerations to enable dental hygienists to undertake an informed approach to patient management strategies and provide optimal care.  相似文献   
39.

Introduction

The high mortality and morbidity associated with resection for oesophagogastric malignancy has resulted in a conservative approach to the postoperative management of this patient group. In August 2009 we introduced an enhanced recovery after surgery (ERAS) pathway tailored to patients undergoing resection for oesophagogastric malignancy. We aimed to assess the impact of this change in practice on standard clinical outcomes.

Methods

Two cohorts were studied of patients undergoing resection for oesophagogastric malignancy before (August 2008 – July 2009) and after (August 2009 – July 2010) the implementation of the ERAS pathway. Data were collected on demographics, interventions, length of stay, morbidity and in-hospital mortality.

Results

There were 53 and 55 oesophagogastric resections undertaken respectively for malignant disease in each of the study periods. The median length of stay for both gastric and oesophageal resection decreased from 15 to 11 days (Mann– Whitney U, p<0.001) following implementation of the ERAS pathway. There was no significant increase in morbidity (gastric resection 23.1% vs 5.3% and oesophageal resection 25.9% vs 16.7%) or mortality (gastric resection no deaths and oesophageal resection 1.8% vs 3.6%) associated with the changes. There was a significant decrease in the number of oral contrast studies used following oesophageal resection, with a reduction from 21 (77.8%) in 2008–2009 to 6 (16.7%) in 2009–2010 (chi-squared test, p<0.0001).

Conclusions

The introduction of an enhanced recovery programme following oesophagogastric surgery resulted in a significant decrease in length of median patient stay in hospital without a significant increase in associated morbidity and mortality.  相似文献   
40.
Chronic progressive multisystem granulomatous disease is seen in 10-30% of patients with sarcoidosis and can result in end organ damage. Corticosteroids are the mainstay of treatment with the addition of cytotoxic agents in severe cases. Some patients are refractory to such treatment and, therefore, management is a challenge. There is currently limited evidence for biological agents such as infliximab, a monoclonal anti-tumor necrosis factor-α antibody in the treatment of multisystem sarcoidosis. We report outcomes of three patients with extensive multisystem sarcoidosis refractory to conventional treatment and treated at our center. Clinical assessment and radiographic imaging were used to assess the response to infliximab treatment. Infliximab therapy induced clinical remission in all three patients, and this clinical response correlated with radiographic evidence of the resolution of granulomatous disease. Serum ACE level was reduced in all cases, and daily steroid dosage was reduced. We propose that infliximab can be an effective treatment in patients with multisystem complex sarcoidosis refractory to conventional drug therapy and can result in sustained clinical remission. Our experience supports the urgent need for randomized controlled clinical trials of anti-TNF therapy in refractory systemic sarcoidosis.  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