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   943篇
  免费   32篇
电工技术   8篇
综合类   4篇
化学工业   80篇
金属工艺   8篇
机械仪表   10篇
建筑科学   37篇
能源动力   15篇
轻工业   77篇
水利工程   14篇
石油天然气   1篇
无线电   59篇
一般工业技术   99篇
冶金工业   497篇
原子能技术   8篇
自动化技术   58篇
  2022年   10篇
  2021年   11篇
  2020年   7篇
  2019年   7篇
  2018年   16篇
  2017年   8篇
  2016年   10篇
  2015年   14篇
  2014年   22篇
  2013年   29篇
  2012年   35篇
  2011年   34篇
  2010年   33篇
  2009年   16篇
  2008年   35篇
  2007年   26篇
  2006年   16篇
  2005年   16篇
  2004年   23篇
  2003年   17篇
  2002年   10篇
  2001年   6篇
  2000年   6篇
  1999年   16篇
  1998年   153篇
  1997年   101篇
  1996年   42篇
  1995年   34篇
  1994年   35篇
  1993年   30篇
  1992年   7篇
  1991年   7篇
  1990年   9篇
  1989年   7篇
  1988年   12篇
  1987年   6篇
  1986年   11篇
  1985年   5篇
  1984年   5篇
  1982年   5篇
  1981年   3篇
  1980年   7篇
  1979年   7篇
  1978年   3篇
  1977年   11篇
  1976年   27篇
  1975年   4篇
  1974年   5篇
  1972年   3篇
  1969年   3篇
排序方式: 共有975条查询结果,搜索用时 10 毫秒
971.
In the lung, glycosaminoglycans (GAGs) are dispersed in the extracellular matrix (ECM) occupying the interstitial space between the capillary endothelium and the alveolar epithelium, in the sub-epithelial tissue and in airway secretions. In addition to playing key structural roles, GAGs contribute to a number of physiologic processes ranging from cell differentiation, cell adhesion and wound healing. Cytokine and chemokine–GAG interactions are also involved in presentation of inflammatory molecules to respective receptors leading to immune cell migration and airway infiltration. More recently, pathophysiological roles of GAGs have been described. This review aims to discuss the biological roles and molecular interactions of GAGs, and their impact in the pathology of chronic airway diseases, such as cystic fibrosis and chronic obstructive pulmonary disease. Moreover, the role of GAGs in respiratory disease has been heightened by the current COVID-19 pandemic. This review underlines the essential need for continued research aimed at exploring the contribution of GAGs in the development of inflammation, to provide a better understanding of their biological impact, as well as leads in the development of new therapeutic agents.  相似文献   
972.
Microbial dysbiosis has emerged as a modulator of oncogenesis and response to therapy, particularly in lung cancer. Here, we investigate the evolution of the gut and lung microbiomes following exposure to a tobacco carcinogen. We performed 16S rRNA-Seq of fecal and lung samples collected prior to and at several timepoints following (nicotine-specific nitrosamine ketone/NNK) exposure in Gprc5a−/− mice that were previously shown to exhibit accelerated lung adenocarcinoma (LUAD) development following NNK exposure. We found significant progressive changes in human-relevant gut and lung microbiome members (e.g., Odoribacter, Alistipes, Akkermansia, and Ruminococus) that are closely associated with the phenotypic development of LUAD and immunotherapeutic response in human lung cancer patients. These changes were associated with decreased short-chain fatty acids (propionic acid and butyric acid) following exposure to NNK. We next sought to study the impact of Lcn2 expression, a bacterial growth inhibitor, given our previous findings on its protective role in LUAD development. Indeed, we found that the loss of Lcn2 was associated with widespread gut and lung microbiome changes at all timepoints, distinct from those observed in our Gprc5a−/− mouse model, including a decrease in abundance and diversity. Our overall findings apprise novel cues implicating microbial phenotypes in the development of tobacco-associated LUAD.  相似文献   
973.
974.
为研究超低温双螺旋速冻(Ultra-low Temperature Double Spiral Quick Freezing,UTDSQF)对原料猪肉加工品质的影响,该研究以宰后24 h且pH值在正常范围内的猪背最长肌为研究对象,分别采用常规空气冻结(Air-blast Freezing,AF)和超低温双螺旋速冻两种方式对猪背最长肌进行冻结,随后在-20 ℃冷库中冻藏90 d后于4 ℃解冻,加工制成乳化香肠,测定两种冻结方式对其理化、质构和感官品质的影响。研究表明:原料肉不同冻结方式对乳化肠pH值没有显著影响(P>0.05);与AF组相比,UTDSQF组的TBARS值和蒸煮损失分别降低26.67%、31.25%(P<0.05);L*值和a*值显著升高(P<0.05),但b*值显著降低(P<0.05);UTDSQF组的硬度、咀嚼性、回复性和内聚性显著升高(P<0.05),而弹性没有显著性差异(P>0.05);同时,UTDSQF处理原料肉显著提升了乳化肠的感官评分(P<0.05)。因此超低温双螺旋速冻处理能够整体提升原料肉的加工品质。  相似文献   
975.
High fructose corn syrup, or isomerized corn syrup as it is sometimes called, qualifies as a major innovation because this new product is having a revolutionary effect on the important sweetener business. The history of high fructose corn syrup is particularly interesting because of the varied research lessons it teaches. This article traces and analyzes the sequence of events in the development of high fructose corn syrup from the time of the basic discovery and conception of product to the time of commerciallization.  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