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   13143篇
  免费   939篇
  国内免费   50篇
电工技术   228篇
综合类   72篇
化学工业   3422篇
金属工艺   319篇
机械仪表   407篇
建筑科学   468篇
矿业工程   50篇
能源动力   551篇
轻工业   2251篇
水利工程   122篇
石油天然气   80篇
无线电   904篇
一般工业技术   2090篇
冶金工业   1044篇
原子能技术   118篇
自动化技术   2006篇
  2024年   39篇
  2023年   132篇
  2022年   436篇
  2021年   655篇
  2020年   408篇
  2019年   481篇
  2018年   559篇
  2017年   562篇
  2016年   562篇
  2015年   385篇
  2014年   537篇
  2013年   996篇
  2012年   819篇
  2011年   950篇
  2010年   665篇
  2009年   719篇
  2008年   628篇
  2007年   528篇
  2006年   491篇
  2005年   347篇
  2004年   321篇
  2003年   339篇
  2002年   330篇
  2001年   264篇
  2000年   201篇
  1999年   178篇
  1998年   315篇
  1997年   236篇
  1996年   198篇
  1995年   137篇
  1994年   100篇
  1993年   100篇
  1992年   54篇
  1991年   51篇
  1990年   50篇
  1989年   36篇
  1988年   43篇
  1987年   23篇
  1986年   30篇
  1985年   26篇
  1984年   18篇
  1983年   11篇
  1982年   23篇
  1981年   19篇
  1980年   13篇
  1979年   17篇
  1978年   14篇
  1977年   13篇
  1976年   32篇
  1975年   10篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
Alcohol-free beer with isotonic properties is getting more popular and its production can be carried out by different production strategies; however, interrupted fermentation is still a challenge. Therefore, the objective of this study was to develop a low-alcohol isotonic beer (<0.5% v/v) by interrupted fermentation. Moreover, the major objective is to compare the developed product to commercial beverages (sports drinks, ‘Pilsen' regular beer, alcohol-free beers and low-alcohol isotonic beer). The beverages were evaluated based on pH, alcohol content (% v/v), total titratable acidity (mEq L−1), osmolality (mOsmol kg−1), bitterness International Bitterness Units, colour European Brewery Convention, total phenolic compounds (mg L−1 gallic acid), reducing and total sugars (%) and Na and K contents (mg L−1). The developed low-alcohol isotonic beer presented characteristics similar to sports drinks, with the advantage of being richer in phenolic compounds and suitable osmolality. Despite salts were added in its formulation, the grades attributed to all beers employed in the sensory evaluation, as well as the purchase intention did not present significant differences.  相似文献   
12.
13.
14.
15.
Debittered trub (brewing waste) is an important source of protein source (70.26%). Trub and whey protein were used for 5% protein enrichment of ice cream frozen by liquid nitrogen. Three formulations were elaborated: ice cream standard (ICS), ice cream with whey protein (ICW) and ice cream with trub (ICT). Chemical composition, rheological properties, texture, overrun, melting rate, scanning electron microscopy and a sensorial test were performed. Results showed that ICT presented a higher viscosity, obtained on the upward curve up to 6.76 Pa s−1, consistency index (22.96 (Pa s−1)n), hysteresis area (140.40 mPa s−1) and hardness (31113.33 g) but a lower melting rate (0.38 g min−1), overrun (13.92%) and sensorial acceptability than the other formulations. The addition of trub debittered for protein enrichment improved ice cream properties and demonstrated that it could be used as a food ingredient.  相似文献   
16.
Connexin- and pannexin (Panx)-formed hemichannels (HCs) and gap junctions (GJs) operate an interaction with the extracellular matrix and GJ intercellular communication (GJIC), and on account of this they are involved in cancer onset and progression towards invasiveness and metastatization. When we deal with cancer, it is not correct to omit the immune system, as well as neglecting its role in resisting or succumbing to formation and progression of incipient neoplasia until the formation of micrometastasis, nevertheless what really occurs in the tumor microenvironment (TME), which are the main players and which are the tumor or body allies, is still unclear. The goal of this article is to discuss how the pivotal players act, which can enhance or contrast cancer progression during two important process: “Activating Invasion and Metastasis” and the “Avoiding Immune Destruction”, with a particular emphasis on the interplay among GJIC, Panx-HCs, and the purinergic system in the TME without disregarding the inflammasome and cytokines thereof derived. In particular, the complex and contrasting roles of Panx1/P2X7R signalosome in tumor facilitation and/or inhibition is discussed in regard to the early/late phases of the carcinogenesis. Finally, considering this complex interplay in the TME between cancer cells, stromal cells, immune cells, and focusing on their means of communication, we should be capable of revealing harmful messages that help the cancer growth and transform them in body allies, thus designing novel therapeutic strategies to fight cancer in a personalized manner.  相似文献   
17.
18.
19.
20.
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