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   2311083篇
  免费   159696篇
  国内免费   3504篇
耳鼻咽喉   33193篇
儿科学   75445篇
妇产科学   65135篇
基础医学   332552篇
口腔科学   65438篇
临床医学   200107篇
内科学   446876篇
皮肤病学   50885篇
神经病学   181148篇
特种医学   91159篇
外国民族医学   568篇
外科学   352578篇
综合类   45835篇
现状与发展   2篇
一般理论   593篇
预防医学   166010篇
眼科学   52661篇
药学   179211篇
  8篇
中国医学   5143篇
肿瘤学   129736篇
  2018年   26116篇
  2017年   19639篇
  2016年   21697篇
  2015年   23897篇
  2014年   32413篇
  2013年   48947篇
  2012年   67061篇
  2011年   71714篇
  2010年   42212篇
  2009年   38820篇
  2008年   68292篇
  2007年   73094篇
  2006年   73728篇
  2005年   71539篇
  2004年   68501篇
  2003年   66505篇
  2002年   64841篇
  2001年   110625篇
  2000年   114152篇
  1999年   95238篇
  1998年   25905篇
  1997年   22894篇
  1996年   22879篇
  1995年   21527篇
  1994年   19992篇
  1993年   18701篇
  1992年   73133篇
  1991年   71063篇
  1990年   70084篇
  1989年   67744篇
  1988年   62300篇
  1987年   60921篇
  1986年   57778篇
  1985年   54834篇
  1984年   40472篇
  1983年   34788篇
  1982年   20109篇
  1981年   17761篇
  1979年   37369篇
  1978年   25833篇
  1977年   22716篇
  1976年   20651篇
  1975年   23063篇
  1974年   26952篇
  1973年   26012篇
  1972年   24801篇
  1971年   23156篇
  1970年   21421篇
  1969年   20740篇
  1968年   19030篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
31.
32.
33.
34.
35.
Introduction: The treatment of classical Hodgkin lymphoma (cHL) in children is a story of success. Nowadays, more than 90% of patients are cured and overall survival is nearly 100% at 5 years. Efforts have been made to avoid related effects of therapies; therefore, children are treated using different chemotherapy schemes in comparison with adults.

Areas covered: This review includes a view of the clinical classification and risk assessment in children suffering from HL. The chemotherapy more commonly employed is revisited. The use of PET/CT to evaluate the disease in order to guide therapy is analyzed. New options of chemotherapy and emerging immunotherapy are also included.

Expert opinion: In order to make the right treatment choice, a proper initial assessment of risk is mandatory. The choice of therapy in these kinds of patients must be done according to the experience of the team, and also, the cost and logistics related to the eligible scheme are very important. If possible, efforts must be made to include PET/CT in guiding therapy and avoiding overtreatment and long-term adverse effects in children. New options in immunotherapy are emerging and must be considered with caution in selected patients.  相似文献   

36.
37.
To determine percent of patients without malignancy and ≤ 40 years of age with high cumulative radiation doses through recurrent CT exams and assess imaging appropriateness. From the cohort of patients who received cumulative effective dose (CED) of ≥ 100 mSv over a 5-year period, a sub-set was identified with non-malignant disease. The top 50 clinical indications leading to multiple CTs were determined. Clinical decision support (CDS) system scores were analyzed using a widely adopted standard of 1–3 (red) as “not usually appropriate,” 4–6 (yellow) “may or may not be appropriate,” and 7–9 (green) “usually appropriate.” Clinicians reviewed patient records to assess compliance with appropriate use criteria (AUC). 9.6% of patients in our series were with non-malignant conditions and 1.4% with age ≤ 40 years. CDS scores (rounded) were 2% red, 38% yellow, 27% green, and 33% unscored CTs. Clinical society guidelines for CT exams, wherever available, were followed in 87.5 to 100% of cases. AUCs were not available for several clinical indications as also referral guidelines for serial CT imaging. More than half of CT exams were unrelated to follow-up of a primary chronic disease. We are faced with a situation wherein patients in age ≤ 40 years require or are thought to require many CT exams over the course of a few years but the radiation risk creates concern. There is a fair number of conditions for which AUC are not available. Suggested solutions include development of CT scanners with lesser radiation dose and further development of appropriateness criteria.  相似文献   
38.
39.
40.

Objective

To examine whether a healthy weight intervention embedded in the Parents as Teachers (PAT) home visiting program, which was previously found to improve mothers’ body mass index (BMI) and obesity-related behaviors, changed the BMI of preschool children or maternal feeding practices.

Methods

This stratified randomized trial included preschool-aged children at risk for overweight whose mothers were overweight or had obesity (n?=?179). The Healthy Eating and Active Living Taught at Home (HEALTH) intervention was based on the Diabetes Prevention Program. Differences were examined using repeated-measures mixed-ANOVA models.

Results

Compared with PAT usual care, the HEALTH intervention had no effect on children's BMI or maternal feeding practices. However, combined analyses showed that children's BMI percentile decreased (P??=?.007), BMI z-scores were maintained (P??=?.19), and 3 of 8 feeding practices improved over time (P < .05).

Conclusions and Implications

Additional research is needed to assess the effectiveness of PAT to prevent preschool-age obesity using rigorous designs (eg, group-randomized trials) and to identify its active components. HEALTH is ready to be scaled up to prevent maternal weight gain through embedding within the national PAT program.  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