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   1025305篇
  免费   67979篇
  国内免费   1339篇
耳鼻咽喉   13642篇
儿科学   27630篇
妇产科学   24693篇
基础医学   144266篇
口腔科学   28771篇
临床医学   86399篇
内科学   202335篇
皮肤病学   19691篇
神经病学   81716篇
特种医学   41047篇
外国民族医学   79篇
外科学   168466篇
综合类   18840篇
现状与发展   1篇
一般理论   234篇
预防医学   70288篇
眼科学   22274篇
药学   77544篇
  3篇
中国医学   2167篇
肿瘤学   64537篇
  2018年   19947篇
  2017年   15958篇
  2016年   18444篇
  2015年   9239篇
  2014年   12282篇
  2013年   17756篇
  2012年   27114篇
  2011年   34791篇
  2010年   22589篇
  2009年   20088篇
  2008年   34743篇
  2007年   38244篇
  2006年   26707篇
  2005年   27432篇
  2004年   27046篇
  2003年   27287篇
  2002年   25590篇
  2001年   55020篇
  2000年   57043篇
  1999年   47129篇
  1998年   10920篇
  1997年   9721篇
  1996年   9745篇
  1995年   9087篇
  1994年   8442篇
  1993年   7726篇
  1992年   35621篇
  1991年   34054篇
  1990年   32871篇
  1989年   31993篇
  1988年   29100篇
  1987年   28371篇
  1986年   26395篇
  1985年   25249篇
  1984年   17907篇
  1983年   15210篇
  1982年   7884篇
  1981年   6785篇
  1979年   15884篇
  1978年   10665篇
  1977年   9071篇
  1976年   7946篇
  1975年   8629篇
  1974年   10500篇
  1973年   9868篇
  1972年   9358篇
  1971年   8852篇
  1970年   8450篇
  1969年   7959篇
  1968年   7225篇
排序方式: 共有10000条查询结果,搜索用时 203 毫秒
141.
142.
143.
144.
145.
Peacekeeping missions involve experiences that may impact the mental health of participating soldiers. However, research on the long-term mental health consequences of peacekeeping is sparse. The present study aimed to find the prevalence of mental health problems (MHPs), possible MHP predictors, and associations between predictors and MHPs in Norwegian peacekeepers 18–38 years after deployment to a United Nations peacekeeping mission. We used data from a cross-sectional, postdeployment survey of Norwegian peacekeepers who served in Lebanon between 1978 and 1998 (N = 10,605). Participants were assessed for posttraumatic stress disorder (PTSD); anxiety; depression; insomnia; alcohol misuse; drug misuse; and exposure to pre-, peri-, and postdeployment stressors. Logistic regressions were executed to explore key variables associated with MHPs. Total MHP prevalence was 15.1%, 95% CI [14.4, 15.8]. The estimates for specific disorders were 0.1% for drug misuse, 3.4% for alcohol misuse, 4.0% for depression, 6.2% for PTSD, 6.4% for anxiety, and 9.3% for insomnia. Postdeployment stressors, OR = 1.91, 95% CI [1.79, 2.04]; employment status, OR = 1.41, 95% CI [1.33, 1.48]; and traumatic exposure during deployment, OR = 1.11, 95% CI [1.09, 1.12], were positively related to PTSD, χ2(17, N = 8,568) = 1,791.299, p < .001. Similar patterns were found for the other MHPs. Considering that most participants (84.9%) reported low symptom levels, our findings challenge the widespread public perception that most peacekeepers have MHPs. Moreover, our results indicate that future peacekeepers should be prepared for challenges they may face not only during deployment but also in the years following their homecoming.  相似文献   
146.
147.
Postoperative pulmonary complications are associated with an increase in mortality, morbidity and healthcare utilisation. The Agency for Healthcare Research and Quality recommends risk assessment for postoperative respiratory complications in patients undergoing surgery. In this hospital registry study of adult patients undergoing non-cardiac surgery between 2005 and 2017 at two independent healthcare networks, a prediction instrument for early postoperative tracheal re-intubation was developed and externally validated. This was based on the development of the Score for Prediction Of Postoperative Respiratory Complications. For predictor selection, stepwise backward logistic regression and bootstrap resampling were applied. Development and validation cohorts were represented by 90,893 patients at Partners Healthcare and 67,046 patients at Beth Israel Deaconess Medical Center, of whom 699 (0.8%) and 587 (0.9%) patients, respectively, had their tracheas re-intubated. In addition to five pre-operative predictors identified in the Score for Prediction Of Postoperative Respiratory Complications, the final model included seven additional intra-operative predictors: early post-tracheal intubation desaturation; prolonged duration of surgery; high fraction of inspired oxygen; high vasopressor dose; blood transfusion; the absence of volatile anaesthetic use; and the absence of lung-protective ventilation. The area under the receiver operating characteristic curve for the new score was significantly greater than that of the original Score for Prediction Of Postoperative Respiratory Complications (0.84 [95%CI 0.82–0.85] vs. 0.76 [95%CI 0.75–0.78], respectively; p < 0.001). This may allow clinicians to develop and implement strategies to decrease the risk of early postoperative tracheal re-intubation.  相似文献   
148.
149.
Schizophrenia is a chronic and severe psychiatric disorder that has profound impact on an individual’s life and on society. Thus, developing more effective therapeutic interventions is essential. Over the past quarter‐century, an abundance of evidence from pharmacologic challenges, post‐mortem studies, brain imaging, and genetic studies supports the role of glutamatergic dysregulation in the pathophysiology of schizophrenia, and the results of recent randomized clinical trials based on this evidence have yielded promising results. In this article, we review the evidence that alterations in glutamatergic neurotransmission, especially focusing on the N‐methyl‐d ‐aspartate receptor (NMDAR) function, may be a critical causative feature of schizophrenia, how this contributes to pathologic circuit function in the brain, and how these insights are revealing whole new avenues for treatment development that could reduce treatment‐resistant symptoms, which account for persistent disability.  相似文献   
150.
This paper reviews the published literature on a group of developmental disorders of the retina and retinal pigment epithelium which result in focal abnormalities in one or both eyes. They are often asymptomatic, found on routine examination and are generally non-progressive. Some are associated with other systemic abnormalities.Subject terms: Retinal diseases, Eye abnormalities  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