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   85510篇
  免费   6767篇
  国内免费   1735篇
耳鼻咽喉   728篇
儿科学   1985篇
妇产科学   1108篇
基础医学   3600篇
口腔科学   4508篇
临床医学   8048篇
内科学   10342篇
皮肤病学   1523篇
神经病学   5255篇
特种医学   2105篇
外国民族医学   21篇
外科学   8921篇
综合类   15058篇
现状与发展   8篇
一般理论   4篇
预防医学   6075篇
眼科学   1539篇
药学   8277篇
  159篇
中国医学   8891篇
肿瘤学   5857篇
  2024年   312篇
  2023年   1425篇
  2022年   2561篇
  2021年   3517篇
  2020年   3771篇
  2019年   2886篇
  2018年   2680篇
  2017年   2983篇
  2016年   3253篇
  2015年   2995篇
  2014年   5888篇
  2013年   8019篇
  2012年   5743篇
  2011年   6036篇
  2010年   5073篇
  2009年   4396篇
  2008年   3869篇
  2007年   4103篇
  2006年   3657篇
  2005年   3100篇
  2004年   2614篇
  2003年   2274篇
  2002年   1895篇
  2001年   1537篇
  2000年   1322篇
  1999年   1022篇
  1998年   843篇
  1997年   773篇
  1996年   646篇
  1995年   567篇
  1994年   526篇
  1993年   452篇
  1992年   370篇
  1991年   335篇
  1990年   245篇
  1989年   255篇
  1988年   229篇
  1987年   214篇
  1986年   199篇
  1985年   247篇
  1984年   198篇
  1983年   133篇
  1982年   174篇
  1981年   137篇
  1980年   124篇
  1979年   114篇
  1978年   65篇
  1977年   61篇
  1976年   49篇
  1975年   31篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
61.
In order to make effective use of the statistical theory of design of clinical trials for chronic diseases such as periodontal disease, certain issues must be considered. Any clinical trial requires that the disease definition be well-specified; that patient eligibility be explicit; that the observation times be explicit; that the duration and endpoint of therapy be specified; that the duration of subsequent followup observation be specified; and that the unit of observation (e.g., tooth, set of teeth, patient) be defined. In a chronic disease, the potential biases that can readily be introduced by self-selection of patients who enter the trial and/or who return for subsequent observation become more important, because subjects are required to remain on treatment and/or observation for prolonged periods. Further, the cyclical nature of some chronic diseases may require special attention to baseline definitions of active disease and disease outcome. These issues are illustrated with examples from clinical trials of hypertension, breast cancer screening, and Polycythemia Vera. Implications for periodontal disease are discussed.  相似文献   
62.
腔内激光治疗大隐静脉曲张192例报告   总被引:4,自引:1,他引:3  
目的 探讨腔内激光治疗大隐静脉曲张的疗效。方法 2004年7月~2006年3月我院对192例238条肢体大隐静脉曲张行高位结扎、激光烧灼静脉主干和小腿曲张静脉。小腿局部严重曲张的静脉团,另做切口做局部切除或点状抽拨。结果 本组一次治愈率96.2%(229/238)。9例9条肢体术后因仍有少量曲张静脉存在,局麻下行切除或再次激光治愈。114例大隐静脉主干及小腿局部条索状硬结、疼痛;9例皮肤灼伤。术后住院时间4~8 d,平均5.6 d。158例随访1~18个月,平均11.6月,未见复发。结论 腔内激光治疗大隐静脉曲张效果确切,创伤小。  相似文献   
63.
The choice of therapies for Crohn's disease has expanded greatly over the past 30 years. Increasingly it is important that we attempt to identify subgroups of patients who will benefit most from each type of therapy. This article reviews the therapeutic options currently available, organized by the goal the practitioner hopes to achieve. Imaging is one critical way of aiding the classification of Crohn's disease by attempting to accurately determine the location, extent and, most importantly, the nature of the disease.  相似文献   
64.
65.
Chronic headaches are difficult to treat and represent the biggest challenge in headache centres. Mirtazapine has a prophylactic and ibuprofen an acute effect in tension-type headache. Combination therapy may increase efficacy and lower side effects. We aimed to evaluate the prophylactic effect of a combination of low-dose mirtazapine and ibuprofen in chronic tension-type headache. Ninety-three patients were included in the double-blind, placebo-controlled, parallel trial. Following a 4-week run-in period they were randomized to four groups for treatment with a combination of mirtazapine 4.5 mg and ibuprofen 400 mg, placebo, mirtazapine 4.5 mg or ibuprofen 400 mg daily for 8 weeks. Eighty-four patients completed the study. The primary efficacy parameter, change in area under the headache curve from run-in to the last 4 weeks of treatment, did not differ between combination therapy (190) and placebo (219), P  = 0.85. Explanatory analyses revealed worsening of headache already in the third week of treatment with ibuprofen alone. In conclusion, the combination of low-dose mirtazapine and ibuprofen is not effective for the treatment of chronic tension-type headache. Moreover, the study suggests that daily intake of ibuprofen worsens headache already after few weeks in chronic tension-type headache.  相似文献   
66.
本文通过复习相关文献资料,就早期胰岛素强化序贯治疗在ICU病人治疗中应用的几个主要方面进行扼要的综述,以利临床医生的参考。  相似文献   
67.
肝移植术后并发胆道狭窄和胆泥淤积影像诊断及介入治疗   总被引:1,自引:0,他引:1  
目的:评价肝移植术后胆道狭窄和胆泥淤积影像诊断及介入治疗的价值。方法:对39例肝移植术后并发胆道狭窄和胆泥淤积的影像诊断及介入治疗进行回顾性分析。结果:超声、T型管胆道造影、CT和MRI检查诊断胆道狭窄伴胆泥形成39例,38例介入治疗后胆道梗阻症状明显缓解;1例介入治疗后胆道梗阻症状未明显改善,后行外科胆管修补术。结论:T型管胆道造影或直接经皮胆道造影对肝移植术后胆道狭窄和胆泥淤积诊断特异性及敏感性最高,放射介入和内镜介入技术对其均发挥重要的治疗作用。  相似文献   
68.
69.
Milieu relationships provide the critical background presence to staff's attempts to motivate, regulate, and teach patients how to cope with stress. Forging a connection with hospitalized children and adolescents demands attention to how they respond to adults and engage with staff around milieu expectations. Assessment guides that deal with these issues are presented. Important aspects of children's relatedness are presented in the context of their working models of adults and the influence of these representations on their response to staff. Coping skills are explained with particular emphasis on behavioral coping strategies. Tied to the assessment process are interventions that emphasize staff's role in helping patients manage strong affects and avoid the use of nonproductive behavior regulation strategies.  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