全文获取类型
收费全文 | 179篇 |
免费 | 38篇 |
出版年
2021年 | 2篇 |
2019年 | 2篇 |
2017年 | 4篇 |
2016年 | 5篇 |
2015年 | 10篇 |
2014年 | 8篇 |
2013年 | 4篇 |
2012年 | 8篇 |
2011年 | 11篇 |
2010年 | 13篇 |
2009年 | 7篇 |
2008年 | 5篇 |
2007年 | 10篇 |
2006年 | 10篇 |
2005年 | 6篇 |
2004年 | 4篇 |
2003年 | 5篇 |
2002年 | 6篇 |
2001年 | 3篇 |
2000年 | 5篇 |
1999年 | 3篇 |
1998年 | 5篇 |
1997年 | 3篇 |
1996年 | 4篇 |
1993年 | 2篇 |
1991年 | 7篇 |
1990年 | 2篇 |
1988年 | 3篇 |
1986年 | 3篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1981年 | 2篇 |
1980年 | 3篇 |
1979年 | 4篇 |
1977年 | 3篇 |
1976年 | 6篇 |
1974年 | 2篇 |
1973年 | 1篇 |
1972年 | 4篇 |
1971年 | 1篇 |
1970年 | 3篇 |
1969年 | 4篇 |
1967年 | 3篇 |
1966年 | 2篇 |
1965年 | 1篇 |
1961年 | 1篇 |
1951年 | 1篇 |
1949年 | 1篇 |
1939年 | 1篇 |
1937年 | 2篇 |
排序方式: 共有217条查询结果,搜索用时 198 毫秒
1.
2.
3.
Production of type 5 capsular polysaccharide by Staphylococcus aureus grown in a semi-synthetic medium 总被引:4,自引:0,他引:4
The concentration of the type 5 capsular polysaccharide (CP) antigen of Staphylococcus aureus can be measured directly in cultures or cell suspensions by a two-step inhibition enzyme-linked immunosorbent assay (ELISA), using monoclonal antibodies. CP was synthesized during growth on a variety of carbon substrates and its production was not affected by the nature of the carbon source. High levels of yeast extract inhibited CP formation. CP was synthesized in batch culture at the same rate during exponential growth as in the post-exponential phase. Post-exponential CP production contributed at least half the final amount of CP measured. This phenomenon was observed in different culture media, although the specific yield of polysaccharide varied from one medium to another. Post-exponential CP production was observed in the pH range 6-7, but not at pH 8. Post-exponential production was strictly dependent on oxygen availability and did not occur under anaerobic conditions. 相似文献
4.
Anesthetic inhibition of firefly luciferase, a protein model for general anesthesia, does not exhibit pressure reversal. 总被引:3,自引:1,他引:2
下载免费PDF全文
![点击此处可从《Biophysical journal》网站下载免费的PDF全文](/ch/ext_images/free.gif)
The surprising observation that pressures of the order of 150 atmospheres can restore consciousness to an anesthetized animal has long been central to theories of the molecular mechanisms underlying general anesthesia. We have constructed a high-pressure gas chamber to test for "pressure reversal" of the best available protein model of general anesthetic target sites: the pure enzyme firefly luciferase, which accounts extremely well for animal potencies (over a 100,000-fold range). We found no significant pressure reversal for a variety of anesthetics of differing size and polarity. It thus appears that either firefly luciferase is not an adequate model for general anesthetic target sites or that pressure and anesthetics act at different molecular sites in the central nervous system. 相似文献
5.
Summary The binding of genecI product to DNA was studied at temperatures from 0°C to 46° C. Binding activity of the products ofcIts mutants was higher at 22° C than at 0° C, 26° C or 30° C. BothcI+ andcIts products lost DNA-binding activity at 46° C, but after subsequent cooling to 22° C, they regained 50–100% of their activity. 相似文献
6.
7.
8.
Julian Gutt Mattias Cape Werner Dimmler Laura Fillinger Enrique Isla Verena Lieb Tomas Lundälv Christian Pulcher 《Polar Biology》2013,36(6):895-906
The aim of this study was to contribute to a general understanding of the response of the Antarctic macrobenthos to environmental variability and climate-induced changes. The change in population size of selected macrobenthic organisms was investigated in the Larsen A area east of the Antarctic Peninsula in 2007 and 2011 using ROV-based imaging methods. The results were complemented by data from the Larsen B collected in 2007 to allow a conceptual reconstruction of the environment-driven changes before the period of investigation. Both Larsen areas are characterised by ice-shelf disintegration in 1995 and 2002, respectively, as well as high inter-annual variability in sea-ice cover and oceanographic conditions. In 2007 one ascidian species, Molgula pedunculata, was abundant north and south of the stripe of remaining ice shelf between Larsen A and B. Population densities decreased drastically in the Larsen A between 2007 and 2011, coincident with the decrease in Corella eumyota, another ascidian. Among the ophiuroids, the population of deposit feeders increased, while suspension feeders halved their abundance. Current measurements indicated a northward flow between the Larsen B and Larsen A, suggesting that a major physical forcing on benthic population development comes from the South. The results demonstrate that Antarctic macrobenthic populations can exhibit dramatic population dynamics. Analyses of sea-ice dynamics, salinity, temperature and surprisingly ice-shelf disintegration history, however, did not provide any clear evidence for environmental drivers underlying the apparent changes. 相似文献
9.
Angiopoietin‐2, its soluble receptor Tie‐2, and metabolic syndrome components in a population‐based sample
下载免费PDF全文
![点击此处可从《Obesity (Silver Spring, Md.)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
10.
Hans-Christoph Steinhausen Helle Jakobsen Andrea Meyer Povl Munk J?rgensen Roselind Lieb 《PloS one》2016,11(1)