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   5814篇
  免费   369篇
  国内免费   28篇
耳鼻咽喉   92篇
儿科学   137篇
妇产科学   63篇
基础医学   710篇
口腔科学   113篇
临床医学   429篇
内科学   1314篇
皮肤病学   115篇
神经病学   323篇
特种医学   167篇
外国民族医学   2篇
外科学   952篇
综合类   109篇
一般理论   9篇
预防医学   416篇
眼科学   170篇
药学   518篇
中国医学   51篇
肿瘤学   521篇
  2023年   68篇
  2022年   195篇
  2021年   305篇
  2020年   144篇
  2019年   171篇
  2018年   224篇
  2017年   151篇
  2016年   165篇
  2015年   220篇
  2014年   287篇
  2013年   254篇
  2012年   446篇
  2011年   484篇
  2010年   313篇
  2009年   229篇
  2008年   337篇
  2007年   336篇
  2006年   321篇
  2005年   306篇
  2004年   259篇
  2003年   264篇
  2002年   205篇
  2001年   57篇
  2000年   41篇
  1999年   40篇
  1998年   51篇
  1997年   28篇
  1996年   37篇
  1995年   21篇
  1994年   22篇
  1993年   19篇
  1992年   22篇
  1991年   13篇
  1990年   12篇
  1989年   11篇
  1988年   14篇
  1987年   6篇
  1985年   12篇
  1984年   9篇
  1983年   14篇
  1982年   17篇
  1981年   9篇
  1980年   8篇
  1979年   5篇
  1978年   10篇
  1977年   4篇
  1974年   4篇
  1973年   5篇
  1972年   4篇
  1971年   5篇
排序方式: 共有6211条查询结果,搜索用时 15 毫秒
21.
Treatment of metastatic castrate resistant prostate cancer (mCRPC) after progression on docetaxel chemotherapy is a challenging clinical scenario with limited availability of treatment options. Re-treatment with docetaxel, either as monotherapy or in combination with other cytotoxics or targeted agents has shown durable responses. However, most docetaxel re-treatment studies have been either retrospective or early phase non-randomised studies which have not formally assessed Quality of life or survival gain with re-treatment. Despite limited evidence for efficacy of mitoxantrone in the second-line, it continues to remain widely used, largely due to lack of available suitable alternatives. Cabazitaxel in combination with prednisolone is the only chemotherapy to have shown a significant survival benefit and receive approval by the U.S. Food and Drug Administration for patients with mCRPC previously treated with a docetaxel-based regimen. Abiraterone acetate has recently demonstrated a significant improvement in survival when compared to placebo in patients with docetaxel-treated mCRPC. This review aims to summarize the current evidence and discuss future strategies for treatment of mCRPC patients following failure of docetaxel chemotherapy.  相似文献   
22.
Although the antioxidant properties of flavonoids are well documented, it is still unclear whether these effects are dependent on radical scavenging or iron chelating activities. Oxidative stress, a state of excessive reactive oxygen species (ROS) activity, is associated with vascular disease conditions such as hypertension. Both the anti‐ and pro‐oxidant effects of tea catechins have been implicated in the alterations of cellular functions that determine their chemoprotective and therapeutic potentials in health and diseases. The present study examined the concentration dependent (10?7 to 10?4 m ) effects of (?)‐epicatechin and L‐ascorbic acid on Na+/K+‐ATPase and Ca2+‐ATPase activity in hypertensive patients and normal subjects. L‐ascorbic acid has been used as a positive control to compare the effect of (?)‐epicatechin. A significant (p < 0.0001) decrease in the activities of Na+/K+‐ATPase and Ca2+‐ATPase was observed in hypertensive patients compared with normal subjects. We report that (?)‐epicatechin shows a significant (p < 0.001) dose‐dependent protective effect against oxidative stress induced by tert‐butyl hydroperoxide (t‐BHP), which is manisfested as a decrease in the activity of erythrocyte Na+/K+‐ATPase and Ca2+‐ATPase, in hypertensive patients as well as normal subjects. The effect of L‐ascorbic acid was also significant (p < 0.001) and was comparable with that of (?)‐epicatechin. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
23.
24.

Background

Low birth weight (LBW) is considered as a major multifaceted public health concern. Seventy-two percent of LBW infants are born in Asia. An estimation of 8% LBW infants has been reported for Eastern Mediterranean region including Iran. This study investigated contributory factors of LBW in singleton term births in Tehran, Iran. Tehran is a multicultural metropolitan area and a sample from the general population in Tehran could be regarded as a representative sample of urban population in Iran.

Methods

This was a retrospective study using data from 15 university maternity hospitals in Tehran, Iran. Data on all singleton term births in these hospitals were extracted from case records during a one calendar year. Study variables included: maternal age, maternal educational level, history of LBW deliveries, history of preterm labor, cigarette smoking during pregnancy, number of parities, chronic diseases and residential area (Tehran versus suburbs of Tehran). In order to examine the relationship between LBW and demographic and reproductive variables the adjusted logistic regression analysis was performed.

Results

In all, data for 3734 term pregnancies were extracted. The mean age of women was 25.7 (SD = 5.3) years and 5.2% of term births were LBW. In addition to association between LBW and maternal age, significant risk factors for LBW were: history of LBW deliveries [adjusted odds ratio (OR) = 2.53, 95% confidence interval (CI) = 1.06–6.03], smoking during pregnancy (OR = 4.64, 95% CI = 1.97–10.95) and chronic diseases (OR for hypertension = 3.70, 95% CI = 2.25–6.06, OR for others = 2.04, 95% CI = 1.09–3.83).

Conclusion

The findings indicate that in addition to maternal age, history of LBW deliveries; smoking during pregnancy and chronic diseases are significant determinants of LBW in this population. This is consistent with national and international findings indicating that maternal variables and risk behaviors during pregnancy play important roles on LBW.  相似文献   
25.
26.
1背景由马来西亚卫生部和马来西亚国民大学(UKM)联合承担的研究项目,主要研究者是Dr·Syed Mohamed AI Junid,研究中心是吉隆坡总医院(GHKL)儿童研究所、UKM医院儿科病房及乌鲁冷岳区(Hulu Langat)医疗中心,研究时间自2004年1月~2006年6月。研究开始前分别获得了马来西亚卫生部  相似文献   
27.
28.
29.
30.
Osteoporosis is a major growing public health problem and it is clear that much needs to be done to bridge the gap between patients and practitioners. However, the educator must have a valid and reliable tool to evaluate the effectiveness of the teaching and learning that are done. Osteoporosis Knowledge Tool (OKT) provides an important strategy for healthcare professionals to start early intervention for patients who are at risk of osteoporosis. The aims of this study were to translate and examine the psychometric properties of the Malaysian version of the Osteoporosis Knowledge Tool (OKT-M) among 250 type 2 diabetes patients and to assess factors that affect diabetic patients’ osteoporosis knowledge. The OKT English version was translated and validated using the internationally accepted and recommended methodology. The sensitivity and specificity of OKT-M was calculated using receiver operating characteristic curve analysis. The face and content validity showed acceptable results. Internal consistency, test–retest reliability, mean difficulty factor and discriminatory power values were 0.72, 0.83, 0.47 ± 0.16 and 0.96, respectively. The cut-off point of the OKT-M to predict osteoporosis/osteopenia was 14 with optimal sensitivity (84.1 %) and specificity (85.5 %). Regression analysis revealed that health belief, self-efficacy and some demographic data had an impact on the OKT-M. The findings of this validation study indicate that the OKT-M is a reliable and valid tool with good psychometric properties in the Malaysian setting. The OKT-M is an appropriate tool for application in clinical setting to identify patients need for a bone health-promoting intervention regarding lifestyle behaviour changes.  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