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   2125篇
  免费   0篇
  国内免费   1篇
电工技术   3篇
综合类   1篇
化学工业   10篇
金属工艺   1篇
机械仪表   38篇
建筑科学   5篇
能源动力   1篇
轻工业   40篇
水利工程   1篇
无线电   5篇
一般工业技术   4篇
冶金工业   2010篇
自动化技术   7篇
  2021年   2篇
  2019年   2篇
  2018年   1篇
  2017年   1篇
  2015年   1篇
  2013年   3篇
  2012年   1篇
  2011年   2篇
  2010年   5篇
  2009年   6篇
  2008年   5篇
  2007年   5篇
  2006年   7篇
  2005年   6篇
  2004年   3篇
  2003年   7篇
  2002年   7篇
  2001年   7篇
  2000年   15篇
  1999年   74篇
  1998年   602篇
  1997年   353篇
  1996年   222篇
  1995年   139篇
  1994年   99篇
  1993年   119篇
  1992年   12篇
  1991年   18篇
  1990年   15篇
  1989年   17篇
  1988年   23篇
  1987年   13篇
  1986年   16篇
  1985年   17篇
  1984年   1篇
  1983年   7篇
  1982年   7篇
  1981年   19篇
  1980年   27篇
  1978年   6篇
  1977年   66篇
  1976年   160篇
  1975年   3篇
  1973年   1篇
  1964年   1篇
  1955年   3篇
排序方式: 共有2126条查询结果,搜索用时 15 毫秒
21.
22.
PURPOSE: Histology has been identified as an important prognostic factor in Hodgkin's disease (HD) in adults. Information regarding the impact of histology on outcome in childhood HD is scarce. This study determines the effect of histology on the overall survival (OS) or progression-free survival (PFS) in a national series of children treated in a standardized manner. PATIENTS AND METHODS: The results of treatment of 331 assessable patients, treated between January 1, 1982 and June 30, 1992, in the United Kingdom Children's Cancer Study Group (UKCCSG) Hodgkin's study I were reviewed to evaluate OS, PFS, and deaths according to stage and histology. Treatment was either involved-field radiation alone (stage IA) or chlorambucil, vinblastine, procarbazine, and prednisolone (ChlVPP) chemotherapy with or without mediastinal radiation. All were clinically staged at diagnosis. RESULTS: Nodular sclerosing (NS) HD was the most common histologic subtype (155 of 331 patients [47%]) and was uniformly distributed through all stages. Lymphocyte-depletion (LD) HD was extremely uncommon (< 1%). Mixed-cellularity (MC) HD had the highest relapse rate, but this was only significant (P < .05) in stage I patients who received local irradiation alone. There was no other statistically significant difference in OS and PFS between the various histologic subtypes. Multivariate analysis for PFS and OS confirmed that stage was the most important prognostic factor and that histology did not have an effect after stratification by stage. CONCLUSION: This study demonstrates that with effective multiagent chemotherapy, histologic subtype does not influence outcome. The high relapse rates in stage I MC subtype indicates that MC HD is biologically aggressive and systemic treatment with or without local irradiation may be indicated. The high relapse rate in stage IV patients appeared to be independent of histology.  相似文献   
23.
Obesity is a major risk factor for cardiovascular disease. However, a direct link between these two states is difficult to establish, since obesity frequently occurs with other disease states such as diabetes, hypertension and atherosclerosis. Clinical studies have clearly shown that uncorrected obesity is associated with cardiac hypertrophy and compromised ventricular function. A number of rodent models of obesity have been studied in terms of cardiovascular adaptations. Cardiac function of the obese Zucker rat appears to be normal at a younger age. Only after several months is depression in cardiac function discernable. These animals are mildly hypertensive, but do not exhibit the characteristic increase in cardiac output associated with human obesity. A unique characteristic of JCR:LA-cp rat is that they develop atherosclerotic and myocardial lesions. Hearts from these animals will maintain normal function when perfused with physiological levels of calcium. At higher calcium concentrations, however, mechanical function becomes impaired. Dietary-induced obese rats exhibit many of the hemodynamic alterations associated with human obesity, but there is no evidence to-date that these animals will develop severe cardiac depression. Short-term weight reduction apparently has beneficial cardiovascular effects, but weight cycling may be harmful. Given the widespread occurrence of obesity, further studies are warranted to characterize the cardiac manifestations of this condition.  相似文献   
24.
25.
26.
27.
28.
29.
A retrospective case reference study examining the use of alcohol and tobacco in 303 women aged 40 or over suffering from oral or oropharyngeal cancer was conducted in the south-west Netherlands. Both alcohol and tobacco consumption are important in the development of oral and oropharyngeal cancer with increased consumption of both markedly increasing the risks of cancer, but alcohol having the greater effect.  相似文献   
30.
We report a case of typical chronic eosinophilic pneumonia (CEP), in a female of 27 years-old suffering bronchial asthma light. Although the initial answer to the treatment with steroids was satisfactory, the patient develop difficult to control asthma (DCA). DCA is a clinical situation which requires careful investigation of several potential factors which can be solved. We suggest a protocol of treatment for patients affected with DCA.  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