首页 | 官方网站   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   111篇
  免费   1篇
工业技术   112篇
  2021年   11篇
  2020年   1篇
  2018年   2篇
  2017年   2篇
  2016年   3篇
  2015年   2篇
  2014年   4篇
  2013年   6篇
  2012年   7篇
  2011年   5篇
  2010年   5篇
  2009年   6篇
  2008年   8篇
  2007年   5篇
  2006年   7篇
  2005年   6篇
  2004年   5篇
  2003年   4篇
  2002年   2篇
  2001年   3篇
  2000年   5篇
  1998年   4篇
  1997年   3篇
  1996年   1篇
  1995年   1篇
  1984年   1篇
  1977年   1篇
  1976年   1篇
  1974年   1篇
排序方式: 共有112条查询结果,搜索用时 15 毫秒
1.
2.
European Journal of Wood and Wood Products - Surface tension of solid wood surfaces affects the wettability and thus the adhesion of various adhesives and wood coatings. By measuring the contact...  相似文献   
3.
The colonization progress of the invasive bivalve dreissenids, the formerly dominant Dreissena polymorpha and the recently (2008) introduced Dreissena rostriformis bugensis was studied between 2009 and 2013 in the largest Central European shallow lake, Lake Balaton, Hungary. The density of dreissenid planktonic veligers, new settlers (post-veligers and early juveniles), and the population structure (density, length frequency, relative abundance) of the two species were monitored on experimentally introduced natural stone substrata, on different time scales. Dreissenids started dynamic settling following a sudden veliger bloom. As substratum saturation progressed, competition between species for places was suggested, which, after two years, led to an increased number of large individuals (> 20 mm) and also recruits of D. r. bugensis. By contrast, the population of D. polymorpha was confined to middle size (11–18 mm) individuals of the first settler generation. On local substrata, where the benthic community was already established, the replacement of D. polymorpha by D. r. bugensis took longer, but it happened in a similar way. The invasion speed of D. r. bugensis in Lake Balaton resembled the speed obtained in other European water bodies where D. r. bugensis, similar to Lake Balaton, was introduced much later than D. polymorpha. However, a longer replacement process was found in North America, where both species invaded new habitats at the same time. This suggests that the speed, and probably the success, of D. r. bugensis invasion depends on new surface availability, and whether the two dreissenid species are introduced together or at different times.  相似文献   
4.
The majority of brain metastases originate from lung cancer, breast cancer and malignant melanoma. In order to reach the brain, parenchyma metastatic cells have to transmigrate through the endothelial cell layer of brain capillaries, which forms the morphological basis of the blood-brain barrier (BBB). The BBB has a dual role in brain metastasis formation: it forms a tight barrier protecting the central nervous system from entering cancer cells, but it is also actively involved in protecting metastatic cells during extravasation and proliferation in the brain. The mechanisms of interaction of cancer cells and cerebral endothelial cells are largely uncharacterized. Here, we provide a comprehensive review on our current knowledge about the role of junctional and adhesion molecules, soluble factors, proteolytic enzymes and signaling pathways mediating the attachment of tumor cells to brain endothelial cells and the transendothelial migration of metastatic cells. Since brain metastases represent a great therapeutic challenge, it is indispensable to understand the mechanisms of the interaction of tumor cells with the BBB in order to find targets of prevention of brain metastasis formation.  相似文献   
5.
6.
7.
8.
In our work the chromium content of foodstuffs, spices, beverages and nutrition supplements was determined. We set out to determine in what quantity these satisfy the organism’s daily chromium requirement. We wanted to get an answer about to the question if a sportsman wants to plan his diet from the chromium consumption point of view, does he believe that the data given satisfy the necessary essential amount of chromium content. The results obtained were compared to data published by other authors and data can be found in the Internet. These data do not only differ significantly from the results obtained by us, but from each other as well. At present there is no available literature data to us demonstrating whether toxic chromium compounds can occur from the natural Cr(III) content of cereal milling products used when baking and toasting bread, that is why we considered examining it.  相似文献   
9.
10.
A component of human synovial fluid (SF) has been separated by micropreparative capillary electrophoresis. The problems associated with application of this technique to a raw body fluid are discussed. Desalting of SF by passage through a capillary formed from polyacrylamide gel is examined and shown to cause loss of hyaluronan polymer as well as low-molecular-mass components of the fluid.  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-23

京公网安备 11010802026262号