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   562篇
  免费   11篇
电工技术   11篇
综合类   1篇
化学工业   40篇
金属工艺   9篇
机械仪表   8篇
建筑科学   10篇
矿业工程   1篇
能源动力   7篇
轻工业   63篇
水利工程   6篇
石油天然气   2篇
无线电   48篇
一般工业技术   60篇
冶金工业   257篇
原子能技术   2篇
自动化技术   48篇
  2021年   3篇
  2020年   3篇
  2018年   6篇
  2017年   6篇
  2016年   5篇
  2015年   5篇
  2014年   8篇
  2013年   18篇
  2012年   17篇
  2011年   27篇
  2010年   19篇
  2009年   24篇
  2008年   22篇
  2007年   14篇
  2006年   23篇
  2005年   15篇
  2004年   17篇
  2003年   10篇
  2002年   12篇
  2001年   14篇
  2000年   17篇
  1999年   13篇
  1998年   30篇
  1997年   28篇
  1996年   18篇
  1995年   10篇
  1994年   18篇
  1993年   17篇
  1992年   5篇
  1991年   3篇
  1990年   6篇
  1988年   7篇
  1987年   7篇
  1986年   10篇
  1985年   11篇
  1984年   5篇
  1983年   7篇
  1980年   6篇
  1979年   4篇
  1978年   5篇
  1977年   6篇
  1976年   12篇
  1975年   4篇
  1974年   6篇
  1973年   4篇
  1972年   5篇
  1970年   7篇
  1969年   5篇
  1968年   3篇
  1963年   5篇
排序方式: 共有573条查询结果,搜索用时 31 毫秒
1.
Presents a model suitable for computing images of absorption cross sections of thick tissue structures illuminated at near infrared (NIR) wavelengths from tomographic projection data. Image reconstruction is accomplished by solving a system of linear equations derived from transport theory. Reconstruction results using different algebraic solvers are shown for anatomical maps of the breast, derived from magnetic resonance imaging data, containing two simulated pathologies, in which case qualitatively good reconstructions were obtained. Evaluation of magnetic resonance (MR) data to optimize NIR optical tomographic imaging methods and to assess the feasibility of a combined MR-optical measurement scheme is discussed  相似文献   
2.
Two studies examined the relationship between the content of a self-threat and the attractiveness of available self-affirmations (C. M. Steele, 1988). After self-threat was induced by means of a cognitive dissonance procedure, participants' choices for affirmations were examined in order to explore whether the attractiveness of a given affirmation depends on its relevance to the threatened domain of the self-concept. The authors hypothesized that when faced with a threat to a specific self-conception or standard, individuals may forego affirmations within the threatened self-concept domain in favor of affirmations of unrelated, compensatory domains. Both studies supported this hypothesis and further suggested that such selective self-affirmation can lead individuals to modify their self-concepts by identifying with self-aspects that justify dissonant behavior and by disidentifying with the standards that such behavior violates. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
4.
OBJECTIVE: To assess the role of DNA ploidy as a predictor of radioresistance in T1 glottic carcinoma. DESIGN: Case-control study. Flow cytometric DNA ploidy measurements were performed on formalin-fixed paraffin-embedded tumor specimens from 15 patients with T1 glottic laryngeal carcinomas in whom radiotherapy had failed and from a matched group of 15 patients in whom an identical radiotherapy regimen was curative. Analysis of DNA content was performed blind to outcome of treatment. SETTING: Academic tertiary referral medical center. PARTICIPANTS: Thirty patients with clinically staged T1, N0, M0 glottic carcinoma. INTERVENTION: All patients received radiation to the larynx through opposed lateral ports at a total dose of 64 to 70 Gy. RESULTS: Ten diploid and five aneuploid histograms were found in the resistant group, and six diploid and nine aneuploid histograms were found in the radiosensitive group. This difference was not statistically significant. A trend toward a higher relapse rate after radiotherapy (62.5%) among patients with diploid tumor compared with those with aneuploid tumor (35.7%) was noted. CONCLUSIONS: DNA ploidy did not predict response to radiotherapy in patients with T1 glottic cancer, probably because of the small number of patients. A trend toward lower risk of local recurrence after radiotherapy in aneuploid tumors was noted. A larger prospective study is needed to assess the value of DNA ploidy in the treatment of early laryngeal cancer.  相似文献   
5.
People differ in the extent to which they emphasize feelings of activation or deactivation in their verbal reports of experienced emotion, termed arousal focus (AF). Two multimethod studies indicate that AF is linked to heightened interoceptive sensitivity (as measured by performance on a heartbeat detection task). People who were more sensitive to their heartbeats emphasized feelings of activation and deactivation when reporting their experiences of emotion over time more than did those who were less sensitive. This relationship was not accounted for by several other variables, including simple language effects. Implications for the role of interoception in experienced emotion and the validity of self-reported emotion are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
7.
8.
9.
10.
PO Leningrad Metallurgical Plant. Translated from Problemy Prochnosti, No. 3, pp. 25–28, March, 1989.  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