全文获取类型
收费全文 | 241篇 |
免费 | 8篇 |
国内免费 | 2篇 |
出版年
2021年 | 4篇 |
2020年 | 3篇 |
2019年 | 3篇 |
2018年 | 7篇 |
2017年 | 7篇 |
2016年 | 4篇 |
2015年 | 7篇 |
2014年 | 12篇 |
2013年 | 4篇 |
2012年 | 14篇 |
2011年 | 15篇 |
2010年 | 7篇 |
2009年 | 13篇 |
2008年 | 10篇 |
2007年 | 5篇 |
2006年 | 7篇 |
2005年 | 11篇 |
2004年 | 3篇 |
2003年 | 12篇 |
2002年 | 3篇 |
2001年 | 6篇 |
2000年 | 7篇 |
1999年 | 6篇 |
1998年 | 8篇 |
1996年 | 2篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1992年 | 7篇 |
1991年 | 4篇 |
1989年 | 6篇 |
1988年 | 3篇 |
1987年 | 4篇 |
1986年 | 3篇 |
1985年 | 7篇 |
1984年 | 4篇 |
1983年 | 4篇 |
1982年 | 3篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1978年 | 5篇 |
1977年 | 1篇 |
1976年 | 2篇 |
1974年 | 2篇 |
1973年 | 2篇 |
1972年 | 1篇 |
1971年 | 2篇 |
1970年 | 1篇 |
1969年 | 2篇 |
1966年 | 2篇 |
1965年 | 1篇 |
排序方式: 共有251条查询结果,搜索用时 31 毫秒
221.
222.
223.
Ascorbic acid given orally to lead exposed rats has similar chelating properties as equimolar amounts of parenterally administered EDTA. Ascorbic acid in combination with EDTA is more than twice as effective as either chelating agent given alone and the combination is particularly effective in removing lead from the central nervous system. 相似文献
224.
225.
226.
227.
228.
Transgenic plants with improved dehydration-stress tolerance: Progress and future prospects 总被引:2,自引:0,他引:2
This review summarizes the recent progress made towards the development of transgenic plants with improved tolerance to water
stress and salinity. Of the various strategies employed, emphasis has been given to the genes engineered for the biosynthesis
of osmoprotectants and osmolytes. This review also briefly discusses the importance of the use of specific stress inducible
promoters and the future prospects of transgenic plants with improved agronomic traits. 相似文献
229.
Metal concentrations in the gill, muscle and liver tissues of Labeo rosae from two impoundments, Loskop and Flag Boshielo dams on the Olifants River, were evaluated in 2011 to detect patterns in metal associations between tissues and impoundments. Elevated concentrations of Ba, Zn, B, Al, Si and Fe, relative to a pristine site in the catchment, were found in the muscle, liver and gill tissues at both impoundments. Molybdenum concentrations were exceptionally high in all tissues at Loskop Dam and in liver at Flag Boshielo Dam. No definite pattern in the ratio metal concentrations within, or between, fish tissues was identified. The expected trend, liver > gills > muscle, was found at both impoundments, but was less prominent at Loskop Dam. Metal concentrations in muscle of Loskop Dam fish were significantly higher than in those at Flag Boshielo Dam. The inverse was true for liver. The long-term impact of elevated metal concentrations on fish health at both impoundments raises concern. 相似文献
230.