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   8365篇
  免费   686篇
  国内免费   11篇
耳鼻咽喉   107篇
儿科学   240篇
妇产科学   202篇
基础医学   1092篇
口腔科学   185篇
临床医学   1123篇
内科学   1662篇
皮肤病学   103篇
神经病学   887篇
特种医学   384篇
外国民族医学   4篇
外科学   800篇
综合类   89篇
预防医学   865篇
眼科学   243篇
药学   686篇
中国医学   6篇
肿瘤学   384篇
  2022年   54篇
  2021年   113篇
  2020年   79篇
  2019年   134篇
  2018年   129篇
  2017年   96篇
  2016年   130篇
  2015年   148篇
  2014年   213篇
  2013年   299篇
  2012年   440篇
  2011年   474篇
  2010年   247篇
  2009年   260篇
  2008年   416篇
  2007年   469篇
  2006年   404篇
  2005年   415篇
  2004年   350篇
  2003年   366篇
  2002年   322篇
  2001年   242篇
  2000年   218篇
  1999年   191篇
  1998年   91篇
  1997年   64篇
  1996年   66篇
  1994年   80篇
  1993年   58篇
  1992年   138篇
  1991年   155篇
  1990年   162篇
  1989年   173篇
  1988年   140篇
  1987年   114篇
  1986年   125篇
  1985年   113篇
  1984年   99篇
  1983年   68篇
  1982年   50篇
  1980年   52篇
  1979年   80篇
  1978年   79篇
  1977年   62篇
  1975年   52篇
  1974年   58篇
  1973年   68篇
  1972年   70篇
  1971年   54篇
  1967年   50篇
排序方式: 共有9062条查询结果,搜索用时 15 毫秒
1.
Biostatisticians play an important role in medical research. They are co-responsible for an appropriate and efficient study design, they are involved in monitoring the study conduct, they plan and perform the data analysis, and they are involved in interpreting and publishing the results. However, how are the biostatisticians prepared for their tasks and responsibilities? Graduate programs in biostatistics are being offered, but some practicing biostatisticians completed their studies in a mathematical or epidemiological program, or obtained their degree in subject-specific fields (such as medicine or biology). Therefore, the expertise and the competencies can vary widely between the individual biostatisticians, also depending on the application field. In this article, focusing on European and US practices, we discuss the required professional expertise for the main areas of applications in the medical field as well as the necessary soft skill competencies of a biostatistician.  相似文献   
2.
3.
An educational intervention was developed to improve family practice residents' ability to obtain useful information from pharmaceutical representatives. The curriculum is based on the traditional one-on-one drug detail. The objectives are to develop residents' skills in controlling the interview, promote skills for critically analyzing drug-promotional material, and discuss ethical issues. The contents include an assessment tool, suggested readings, and interview questions with rationale. After 5 years, residents' confidence in all areas of the curriculum improved significantly.  相似文献   
4.
5.
Fifty women with pyelonephritic renal scarring were prospectively followed for five years and the changes in renal function were related to blood pressure control, plasma renin activity, urinary albumin excretion and the incidence of urinary tract infections (UTI). Five patients (10%) developed end stage renal disease. All these patients had bilateral disease, proteinuria and anti-hypertensive treatment at presentation. The mean +/- SD glomerular filtration rate (GFR) of all patients with renal scarring was 74 +/- 27 ml/min x 1.73 m2 at presentation which was significantly lower than the GFR in 55 patients with a recent episode of acute pyelonephritis (p less than 0.001) and 10 healthy controls (p less than 0.001). GFR and age corrected GFR decreased significantly during follow-up (p less than 0.001) and p less than 0.02 respectively). The decrease in GFR was significantly higher in patients with bilateral scarring, in patients on blood pressure treatment and in patients with an episode of symptomatic UTI during follow-up. Eight patients (16%) had antihypertensive treatment at presentation and another 11 patients (26%), of whom 10 had bilateral scarring, developed hypertension (greater than 140/90 mmHg) during follow-up. Seventy-five per cent of all patients had symptomatic UTI and 40% had an episode of acute pyelonephritis during follow-up. In conclusion, patients with pyelonephritic scarring have a high incidence of UTI and are at high risk of developing renal failure and hypertension. It is essential that recurrent episodes of symptomatic UTI are treated promptly and that blood pressure is monitored carefully in these patients.  相似文献   
6.
Five agents are currently approved for the treatment of chronic hepatitis B infection. This article will discuss the three agents for which the most extensive data are available; interferon (IFN), lamivudine, and adefovir, while the following article by Dr. Jules Dienstag will discuss the recently marketed agents, entecavir and peginterferon alfa-2a. The advantages of IFN are its finite duration of therapy (4–6 months), lack of emergence of resistance, and durability of response. On the negative side, response to IFN is less durable in patients with HBeAg-negative chronic hepatitis B virus (HBV). Also, use of IFN is limited by adverse effects and the mode of administration (daily to thrice-weekly subcutaneous injection). Lamivudine and adefovir are orally administered and have good tolerability and safety. Even in patients who experience a marked decrease in serum HBV DNA and loss of HBeAg, oral therapy needs to be continued for at least 6 months, to avoid the risk of reappearance of HBeAg and viremia. Rates of HBeAg seroconversion to anti-HBe-positivity increase with duration of lamivudine or adefovir therapy. The likelihood of development of resistance to lamivudine and associated viral breakthrough limits its long-term use. In patients with HBeAg-negative chronic hepatitis B, long-term therapy is usually required, as off-treatment relapse is common. The emergence of resistance to adefovir is delayed and infrequent, hence adefovir may be preferred in patients requiring long-term therapy.  相似文献   
7.
8.
9.
10.
In this paper, we will discuss a phase-contrast imaging method that avoids the complications of interferometry to provide phase contrast in weakly absorbing samples. A transversely coherent neutron beam is used with the traditional radiography scheme. Images taken with this scheme show dramatic intensity variations due to sharp changes in the neutron wave refractive index. With some numerical processing these images may be used to reconstruct a quantitative phase radiograph of specimens imaged with this technique.  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