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   3175篇
  免费   70篇
电工技术   24篇
综合类   5篇
化学工业   606篇
金属工艺   47篇
机械仪表   74篇
建筑科学   153篇
矿业工程   8篇
能源动力   113篇
轻工业   341篇
水利工程   29篇
石油天然气   16篇
武器工业   1篇
无线电   263篇
一般工业技术   428篇
冶金工业   760篇
原子能技术   27篇
自动化技术   350篇
  2023年   10篇
  2022年   22篇
  2021年   18篇
  2020年   22篇
  2019年   23篇
  2018年   38篇
  2017年   42篇
  2016年   44篇
  2015年   32篇
  2014年   65篇
  2013年   196篇
  2012年   124篇
  2011年   175篇
  2010年   156篇
  2009年   136篇
  2008年   172篇
  2007年   193篇
  2006年   159篇
  2005年   123篇
  2004年   102篇
  2003年   87篇
  2002年   79篇
  2001年   59篇
  2000年   56篇
  1999年   83篇
  1998年   78篇
  1997年   70篇
  1996年   56篇
  1995年   62篇
  1994年   66篇
  1993年   60篇
  1992年   53篇
  1991年   30篇
  1990年   47篇
  1989年   43篇
  1988年   34篇
  1987年   40篇
  1986年   36篇
  1985年   49篇
  1984年   48篇
  1983年   45篇
  1982年   26篇
  1981年   32篇
  1980年   10篇
  1979年   28篇
  1978年   12篇
  1977年   16篇
  1976年   16篇
  1975年   12篇
  1973年   10篇
排序方式: 共有3245条查询结果,搜索用时 15 毫秒
71.
Alport syndrome (AS) is a hereditary renal disorder with no etiological therapy. In the preclinical Col4a3-/- model of AS, disease progression and severity vary depending on mouse strain. The sodium-glucose cotransporter 2 (SGLT2) is emerging as an attractive therapeutic target in cardiac/renal pathologies, but its application to AS remains untested. This study investigates cardiorespiratory function and SGLT2 renal expression in Col4a3-/- mice from three different genetic backgrounds, 129x1/SvJ, C57Bl/6 and Balb/C. male Col4a3-/- 129x1/SvJ mice displayed alterations consistent with heart failure with preserved ejection fraction (HFpEF). Female, but not male, C57Bl/6 and Balb/C Col4a3-/- mice exhibited mild changes in systolic and diastolic function of the heart by echocardiography. Male C57Bl/6 Col4a3-/- mice presented systolic dysfunction by invasive hemodynamic analysis. All strains except Balb/C males demonstrated alterations in respiratory function. SGLT2 expression was significantly increased in AS compared to WT mice from all strains. However, cardiorespiratory abnormalities and SGLT2 over-expression were significantly less in AS Balb/C mice compared to the other two strains. Systolic blood pressure was significantly elevated only in mutant 129x1/SvJ mice. The results provide further evidence for strain-dependent cardiorespiratory and hypertensive phenotype variations in mouse AS models, corroborated by renal SGLT2 expression, and support ongoing initiatives to develop SGLT2 inhibitors for the treatment of AS.  相似文献   
72.
73.
74.
In hopes of promoting college success among Mexican Americans, researchers have identified factors related to their academic performance. A gap in the literature exists between the interactive role of acculturation, enculturation, and generation status in predicting college self-efficacy and college performance (grade-point average, or GPA). To fill this void, this study investigated the relation of demographic variables (e.g., age, gender, socioeconomic status) and cultural variables (e.g., acculturation, enculturation, generation status) on academic outcomes (e.g., college self-efficacy, college performance) among 408 Mexican-American college students. Results of a series of hierarchical regression analyses indicated socioeconomic status, generation status, enculturation, and acculturation had significant positive effects on college self-efficacy; socioeconomic status and the interaction of higher enculturation and first-generation status were positively and significantly related to GPA. Post-hoc analyses indicated college self-efficacy predicted college performance for students who were second generation and beyond. Implications for research and practice are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
75.
American culture is filled with cultural products. Yet few studies have investigated how changes in cultural products correspond to changes in psychological traits and emotions. The current research fills this gap by testing the hypothesis that one cultural product—word use in popular song lyrics—changes over time in harmony with cultural changes in individualistic traits. Linguistic analyses of the most popular songs from 1980–2007 demonstrated changes in word use that mirror psychological change. Over time, use of words related to self-focus and antisocial behavior increased, whereas words related to other-focus, social interactions, and positive emotion decreased. These findings offer novel evidence regarding the need to investigate how changes in the tangible artifacts of the sociocultural environment can provide a window into understanding cultural changes in psychological processes. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
76.
Norman Garmezy, a pioneer in research on risk and resilience, died in Nashville, Tennessee, on November 21, 2009, at the age of 91. He was a legendary mentor as well as an eminent scientist in clinical psychology. Norm was born on June 18, 1918, in New York City and grew up in the Bronx in a Jewish neighborhood where educational attainment was highly valued. The scientific study of resilience as conceived by Norman Garmezy, his peers, and students has transformed the science and practice of multiple disciplines, from the molecular level to the global ecosystem, infusing a strength-based and recovery-oriented approach into psychology, education, social work, and psychiatry. Current research on resilience ranges from studies of plasticity in brain development to effective planning for resilience in the context of disaster. Norm’s influential ideas and research earned him international acclaim and many honors for lifetime achievements in science. Throughout his career, Norm held many leadership roles. Throughout his life, Norm spoke with great love about his wife of 63 years, Edie Garmezy (who died just months before him in 2009), and their children. In addition to his work and his family, Norm had three abiding passions—theater, movies, and politics. During the last two decades of his life, Norm and those who loved him endured his long decline from Alzheimer’s, which slowly stole his brilliant mind and hilarious sense of humor. Nonetheless, the incredible spirit and humanity of this giant scholar continued to shine through this terrible disease. To the end of his life, Norm’s face would light up with a smile as he greeted the people he loved, and he would often exclaim, “Wonderful!” Norman Garmezy was a remarkable person and scholar who left an extraordinary legacy of love and work to inspire future generations in their efforts to understand and promote the human capacity for competence and resilience. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
77.
In this brief rejoinder, we respond to Farmer, Monaghan, Misyak, and Christiansen (2011). We argue that the data still do not support the claim that reading time is affected by the phonological typicality of a word for its part of speech. We also question Farmer et al.'s claim that interleaving syntactic structures in an experiment modifies grammatically based syntactic expectations. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
78.
79.
The awareness of value management (VM) and the nature and extent of its practice by professional civil, electrical and mechanical engineers in the South African construction industry are investigated using a web-based, online questionnaire survey as the first part of a more extensive investigation. A primary objective of the early study is to test the UK-based assertion of Kelly et al. [Kelly, J., Male, S., Graham, D., 2004. Value Management of Construction Projects. Blackwell, Oxford] that VM is an established service with commonly understood tools, techniques and styles. The survey findings suggest that, while awareness of VM is reasonably prevalent among South African engineers, its practice is considerably less extensive. Where VM is undertaken, almost no attempt is made to benchmark VM activities against international standards nor does its use appear to conform to any standard methodology. Engineers prefer other ways of delivering value to projects, and do not generally employ VM to facilitate the client briefing process. The findings are important given the increasing globalization of construction services, especially given the international ties between designers, project managers and other professionals. Professional engineering associations in South Africa should adopt a proactive role in promoting the use of VM by engineers, possibly through continuing professional development programmes.  相似文献   
80.
This paper examines the role of public art in urban redevelopment, focusing on the reconstruction of Coventry (UK) in the post-war years. Overseen by the city's Chief Architect, Donald Gibson, this redevelopment has often been described as resulting in a placeless and artless urban landscape indistinguishable from other redeveloped city centres in post-war Britain. To the contrary, here it is suggested that public art was an important feature of Coventry's new urban landscape, with the attempt to create a new civic identity manifest in a series of highly symbolic and distinctive public artworks. Analysing both the official symbolism of these artworks and their reception in the public sphere, it is concluded that, although just one aspect of the urban landscape, the production and consumption of public art encapsulated the tensions that existed between different visions of the city.  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