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   28776篇
  免费   2459篇
  国内免费   56篇
耳鼻咽喉   187篇
儿科学   1115篇
妇产科学   837篇
基础医学   4180篇
口腔科学   464篇
临床医学   3745篇
内科学   5195篇
皮肤病学   349篇
神经病学   3243篇
特种医学   607篇
外科学   2745篇
综合类   423篇
一般理论   50篇
预防医学   3674篇
眼科学   504篇
药学   1922篇
中国医学   46篇
肿瘤学   2005篇
  2023年   245篇
  2022年   229篇
  2021年   599篇
  2020年   437篇
  2019年   655篇
  2018年   743篇
  2017年   544篇
  2016年   607篇
  2015年   666篇
  2014年   941篇
  2013年   1365篇
  2012年   1943篇
  2011年   2033篇
  2010年   1080篇
  2009年   1036篇
  2008年   1622篇
  2007年   1851篇
  2006年   1830篇
  2005年   1674篇
  2004年   1636篇
  2003年   1488篇
  2002年   1419篇
  2001年   419篇
  2000年   381篇
  1999年   327篇
  1998年   311篇
  1997年   254篇
  1996年   213篇
  1995年   194篇
  1994年   169篇
  1993年   195篇
  1992年   233篇
  1991年   230篇
  1990年   211篇
  1989年   224篇
  1988年   201篇
  1987年   244篇
  1986年   185篇
  1985年   192篇
  1984年   174篇
  1983年   171篇
  1982年   127篇
  1981年   122篇
  1980年   127篇
  1979年   118篇
  1978年   113篇
  1977年   97篇
  1976年   107篇
  1974年   111篇
  1973年   124篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
Abstract: A qualitative food-frequency questionnaire was administered by mail to a representative sample of 137 people previously diagnosed with possible or definite myocardial infarct. Seventy-eight per cent of subjects returned a completed questionnaire and were subsequently invited to attend local tastings of foods with the National Heart Foundation Tick of Approval. These tastings were organised and promoted with the active involvement of the local branch of the Australian Cardiac Association. The purpose of this study was to measure voluntary participation by people with coronary heart disease in community nutrition education and to identify any self-selection bias with respect to eating habits among the participants. A dietary risk score, which was the proportion of all food choices that were high in fat, was calculated from the data. Eighteen per cent of subjects who answered also participated in the food tastings; there was a statistically significant association between membership of the Australian Cardiac Association and being a participant. Participants had a significantly lower risk score (P < 0.01) after adjustment for age, sex and membership of the association. The results suggest that voluntary participation by people with heart disease in community nutrition education is low and that there is a self-selection bias, with those at highest dietary risk being least likely to attend. The use of existing community networks to recruit participants is also discussed.  相似文献   
62.
63.
Summary: Uraemic dyslipidaemia is a major risk factor for cardiovascular disease in end-stage renal failure patients. In patients without renal failure, high levels and qualitative abnormalities of low-density lipoprotein (LDL) are known to be atherogenic. Recently, LDL subfraction analysis has associated premature coronary artery disease with a high prevalence of small, dense LDL particles characterizing the LDL subclass phenotype B. We therefore examined the lipid profiles, LDL subfraction distribution and phenotypes in our population of haemodialysis (HD; n = 30) and peritoneal dialysis patients (PD; n = 17), and compared them to 40 asymptomatic, non-uraemic volunteers. Dialysis patients had significantly higher triglyceride and VLDL cholesterol concentrations and lower HDL cholesterol and smaller LDL peak particle diameters. PD patients had significantly higher total cholesterol, glycated haemoglobin and fasting blood glucose levels with smaller LDL peak particle diameters (24.4 [0.1] vs 24.8 [0.1 nm] than HD. Both groups showed significant negative correlations between plasma triglyceride and LDL peak particle diameter, and positive correlations between HDL cholesterol and LDL peak particle diameter. All the PD patients expressed the B phenotype (LDL peak diameter ± 25.5 nm) compared to 73% of HD patients. This study demonstrates that HD and especially PD patients have atherogenic lipid profiles which are associated with a predominance of small dense LDL particles and the highly atherogenic LDL subclass phenotype B.  相似文献   
64.
65.
66.
This research investigated the effects of a psychophysiological treatment methodology on brain plasticity as reflected in event-related brain potential topographic mapping and morphology along with School-marks and Mangina-Test performance in three different groups of pre-adolescents at baseline and 8 months later: (a) Learning Disabled/ADHD pre-adolescents who were treated; (b) Non-treated Learning Disabled/ADHD pre-adolescents; (c) Normal controls. Results indicate that: (1) the Event-Related Brain Potentials topographic mapping was significantly modified in post-treatment condition for the treated Learning/Disabled/ADHD group as opposed to pre-treatment baseline (P < 0.001). This was mainly due to the enhanced pre-frontal and frontal N450 amplitudes along with higher P450 components over posterior regions in post-treatment condition (P < 0.001); (2) for group comparisons at baseline, no significant topographic mapping differences were found between the treated Learning Disabled/ADHD group and the non-treated Learning Disabled/ADHD control group (P > 0.05) and significant differences were present between the treated Leaning Disabled/ADHD and the normal control group (P < 0.001); (3) 8 months later, in post-treatment condition, group comparisons revealed significant topographic mapping differences between the treated Learning Disabled/ADHD group and the non-treated Learning Disabled/ADHD control group (P < 0.001) and none between the treated Learning Disabled/ADHD group and the normal control group (P > 0.05); (4) the topographic mapping of both components was similar at baseline and 8 months later in both control groups (P > 0.05); (5) at baseline, school-marks and Mangina-Test performance of treated Learning Disabled/ADHD were not significantly different than those of the non-treated Learning Disabled/ADHD (P > 0.05) and significantly lower than those of the normal control group (P < 0.001); (6) the treated Learning Disabled/ADHD group in post-treatment condition had significantly higher school-marks and Mangina-Test performance than those of non-treated Learning Disabled/ADHD controls (P < 0.001) and were similar to those of normal controls 8 months later (P > 0.05); (7) school-marks and Mangina-Test performance at baseline for non-treated Learning Disabled/ADHD controls were not modified 8 months later (P > 0.05) and normal controls maintained their high performance within the same time interval (P > 0.05). These findings provide evidence of the impact of the psychophysiological treatment methodology on brain plasticity and regulation as reflected in significantly improved neurophysiology of pre-frontal, frontal and posterior brain regions concomitantly with higher school-marks and neuropsychometric performance in the Mangina-Test.  相似文献   
67.
68.
The present paper introduces the concept of the narcissistically vulnerable system by suggesting that organizations may manifest some of the same pathological characteristics as narcissistic individuals. The public mental hospital was chosen as an example of such a system. Reasons for its vulnerability were suggested and specific defenses, employed at the system level, were discussed. Finally, remedies for the repair of the narcissistically vulnerable system were considered.  相似文献   
69.
Abstract  Preference utilitarians are concerned to maximize the autonomous choices of individuals; for this reason, they argue that nurses ought to advocate for those patients who desire assistance with ending their lives. This approach prompts us to consider, then, the moral validity of nursing involvement in measures intended to end the lives of patients. In this article, the terms of preference utilitarianism are set out and considered in order to determine whether this approach offers sufficient philosophical support for sanctioning a role for nursing in euthanasia. Ultimately, it is found that preference utilitarianism is lacking in this respect, as well as in its fitness for guiding nursing activity in general. In particular, it is found that nurses are required to exchange a handmaiden relationship with the medical profession for an equally undignified relationship with patients. If nursing involvement in measures intended to end the lives of patients is to find sufficient philosophical support, then we need to look elsewhere.  相似文献   
70.
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