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   185篇
  免费   9篇
  2023年   2篇
  2020年   3篇
  2019年   7篇
  2018年   3篇
  2017年   2篇
  2016年   3篇
  2015年   8篇
  2014年   9篇
  2013年   8篇
  2012年   9篇
  2011年   12篇
  2010年   6篇
  2009年   3篇
  2008年   5篇
  2007年   5篇
  2006年   6篇
  2005年   2篇
  2004年   3篇
  2003年   8篇
  2002年   4篇
  2001年   7篇
  1999年   7篇
  1998年   3篇
  1996年   2篇
  1995年   2篇
  1993年   2篇
  1988年   6篇
  1985年   3篇
  1980年   2篇
  1974年   2篇
  1971年   1篇
  1970年   1篇
  1968年   4篇
  1967年   1篇
  1966年   4篇
  1965年   3篇
  1960年   2篇
  1953年   1篇
  1928年   1篇
  1927年   1篇
  1918年   1篇
  1913年   2篇
  1912年   1篇
  1911年   4篇
  1910年   2篇
  1908年   1篇
  1906年   1篇
  1904年   1篇
  1903年   1篇
  1901年   2篇
排序方式: 共有194条查询结果,搜索用时 27 毫秒
1.
2.
3.
4.
A simple fabrication method of silver (Ag) nanoislands on ZnO films is presented. Continuous wave and time-resolved photoluminescence and transmission are employed to investigate modifications of visible and UV emissions of ZnO brought about by coupling to localized surface plasmons residing on Ag nanoislands. The size of the nanoislands, determining their absorption and scattering efficiencies, is found to be an important factor governing plasmonic modification of optical response of ZnO films. The presence of the Ag nanoislands of appropriate dimensions causes a strong (threefold) increase in emission intensity and up to 1.5 times faster recombination. The experimental results are successfully described by model calculations within the Mie theory.  相似文献   
5.
6.
Ohne Zusammenfassung Vorgelegt in den Sitzungen der Akademie der Wissensehaften in Krakau im april und Juni 1917. Vgl. Vorl. Mitt. “Kernplasmarelation bei der Eireifung und in den ersten Entwicklungsphasen der Echinodermenkeime”. Bull. de l'Ac. des Sc. Cracovie 1917.  相似文献   
7.
Essential oils of fennel, peppermint, caraway, eucalyptus, geranium and lemon were tested for their antimicrobial activities against some plant pathogenic micro-organisms (Fusarium oxysporum, Alternaria alternate, Penicilium italicum Penicilium digitatum and Botyritus cinerea). Essential oils of fennel, peppermint, caraway were selected as an active ingredient for the formulation of biocides due to their efficiency in controlling the tested micro-organisms. Successful emulsifiable concentrates (biocides) were prepared from these oils using different emulsifiers (Emulgator B.L.M. Tween20 and Tween80) and different fixed oils (sesame, olive, cotton and soybean oils). Physico-chemical properties of the formulated biocide (spontaneous emulsification, emulsion stability test, cold stability and heat stability tests as well as viscosity, surface tension and pH) were measured. The prepared biocides were ready to be tested for application in a future work as a safe pesticide against different pathogens.  相似文献   
8.
Key physiological functions of the intestine are governed by nerves and neurotransmitters. This complex control relies on two neuronal systems: an extrinsic innervation supplied by the two branches of the autonomic nervous system and an intrinsic innervation provided by the enteric nervous system. As a result of constant exposure to commensal and pathogenic microflora, the intestine developed a tightly regulated immune system. In this review, we cover the current knowledge on the interactions between the gut innervation and the intestinal immune system. The relations between extrinsic and intrinsic neuronal inputs are highlighted with regards to the intestinal immune response. Moreover, we discuss the latest findings on mechanisms underlying inflammatory neural reflexes and examine their relevance in the context of the intestinal inflammation. Finally, we discuss some of the recent data on the identification of the gut microbiota as an emerging player influencing the brain function.  相似文献   
9.
In the Americas, areas with a high risk of malaria transmission are mainly located in the Amazon Forest, which extends across nine countries. One keystone step to understanding the Plasmodium life cycle in Anopheles species from the Amazon Region is to obtain experimentally infected mosquito vectors. Several attempts to colonise Ano- pheles species have been conducted, but with only short-lived success or no success at all. In this review, we review the literature on malaria transmission from the perspective of its Amazon vectors. Currently, it is possible to develop experimental Plasmodium vivax infection of the colonised and field-captured vectors in laboratories located close to Amazonian endemic areas. We are also reviewing studies related to the immune response to P. vivax infection of Anopheles aquasalis, a coastal mosquito species. Finally, we discuss the importance of the modulation of Plasmodium infection by the vector microbiota and also consider the anopheline genomes. The establishment of experimental mosquito infections with Plasmodium falciparum, Plasmodium yoelii and Plasmodium berghei parasites that could provide interesting models for studying malaria in the Amazonian scenario is important. Understanding the molecular mechanisms involved in the development of the parasites in New World vectors is crucial in order to better determine the interaction process and vectorial competence.  相似文献   
10.
The synthesis of RNA in guinea pig leukocytes was investigated during sensitization by the use of tritiated uridine. The increase of the number of RNA-synthetizing heterophils was found in 21st day of sensitization. That was connected with morphological features of heterophils nuclei. Among lymphocytes in 11th day of sensitization the subpopulation of cells intensively synthetizing RNA was observed. The possible role of cells, which synthetize RNA in the process of sensitization is discussed.  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