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   21902篇
  免费   2308篇
  国内免费   13篇
  24223篇
  2022年   177篇
  2021年   366篇
  2020年   234篇
  2019年   268篇
  2018年   323篇
  2017年   355篇
  2016年   488篇
  2015年   861篇
  2014年   940篇
  2013年   1060篇
  2012年   1461篇
  2011年   1421篇
  2010年   955篇
  2009年   873篇
  2008年   1189篇
  2007年   1302篇
  2006年   1028篇
  2005年   1086篇
  2004年   1101篇
  2003年   1050篇
  2002年   1002篇
  2001年   400篇
  2000年   413篇
  1999年   351篇
  1998年   303篇
  1997年   221篇
  1996年   172篇
  1995年   164篇
  1994年   172篇
  1993年   165篇
  1992年   253篇
  1991年   243篇
  1990年   199篇
  1989年   219篇
  1988年   187篇
  1987年   183篇
  1986年   180篇
  1985年   201篇
  1984年   210篇
  1983年   146篇
  1982年   123篇
  1981年   136篇
  1980年   124篇
  1979年   123篇
  1978年   114篇
  1977年   106篇
  1976年   107篇
  1974年   114篇
  1972年   95篇
  1970年   99篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
211.
212.
213.
214.
Measurements of intravesical pressure, urinary flow rate, retrograde cystographic residual urine, reflux of contrast medium into the prostatic ducts, and radiological prostate size were made in 45 men with benign prostatic hypertrophy. These factors were all found to be good clinical indices of the degree of urethral resistance to micturition; on the other hand, there was no relation between the latter and the severity of symptoms.  相似文献   
215.
216.
Synopsis A method for the photometric assay of 5-nucleotidase in histochemical preparations of brain is described. The method, which is based upon the determination of the specular density under the microscope of the final reaction product, is shown to be valid statistically because of the correlation of the values obtained by it with those obtained by biochemical assay of the enzyme in adjacent sections. Correlation of the specular density with the amount of lead in the final reaction product is also shown. The accuracy of the method of assay is good as judged by a coefficient of variation of 9.1% in a series of replicate measurements. The assay of the amount of enzymic activity by this method shows that it is linearly proportional to the incubation time for periods of up to 2 hr, and also for sections ranging in thickness from 5 to 20 .  相似文献   
217.
Cytosine arabinoside and daunorubicin used in an intensive intermittent regimen have been shown to be an effective combination for the induction of complete remissions in 14 out of 23 adult patients with acute myelogenous leukaemia. This gives an overall complete remission rate of 60%. A further patient had a good partial remission. The addition of L-asparaginase to the regimen has not increased the incidence of remission and there were more side effects in the L-asparaginasetreated group. Of the 10 patients treated with L-asparaginase in addition to cytosine arabinoside and daunorubicin, five achieved a complete remission. Of the 13 patients treated with cytosine arabinoside and daunorubicin without L-asparaginase, nine achieved a complete remission and one a good partial remission.  相似文献   
218.
Three cases of xylene poisoning occurred after prolonged inhalation of paint fumes. Analysis showed that xylene comprised more than 90% of the solvent in the paint, the total solvent comprising 34% of the paint by weight. One patient was dead on admission, while the other two recovered after at least 15 hours'' loss of consciousness. Both patients had transient liver cell damage, and one temporary impairment of renal function.  相似文献   
219.
An automated follow-up register for the detection of iatrogenic thyroid disease has been established as a joint venture between the general practitioners in the north-east of Scotland and the thyroid clinic of Aberdeen General Hospitals.The data-processing operations in the system are handled by an International Computers Limited 4/50 computer. Patients are followed up at predetermined intervals and the system has been designed to process, screen, and store clinical and biochemical follow-up data and report results to the patients, general practitioners, and the hospital records department.  相似文献   
220.
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