全文获取类型
收费全文 | 641篇 |
免费 | 79篇 |
出版年
2022年 | 4篇 |
2021年 | 5篇 |
2020年 | 4篇 |
2019年 | 5篇 |
2018年 | 5篇 |
2017年 | 8篇 |
2016年 | 10篇 |
2015年 | 23篇 |
2014年 | 25篇 |
2013年 | 21篇 |
2012年 | 35篇 |
2011年 | 24篇 |
2010年 | 26篇 |
2009年 | 19篇 |
2008年 | 27篇 |
2007年 | 19篇 |
2006年 | 31篇 |
2005年 | 21篇 |
2004年 | 36篇 |
2003年 | 17篇 |
2002年 | 20篇 |
2001年 | 26篇 |
2000年 | 24篇 |
1999年 | 16篇 |
1998年 | 24篇 |
1997年 | 14篇 |
1996年 | 9篇 |
1995年 | 12篇 |
1994年 | 5篇 |
1993年 | 10篇 |
1992年 | 11篇 |
1991年 | 8篇 |
1990年 | 9篇 |
1989年 | 7篇 |
1988年 | 10篇 |
1987年 | 14篇 |
1986年 | 5篇 |
1985年 | 6篇 |
1984年 | 8篇 |
1983年 | 6篇 |
1982年 | 7篇 |
1979年 | 9篇 |
1976年 | 6篇 |
1972年 | 4篇 |
1971年 | 4篇 |
1970年 | 3篇 |
1968年 | 6篇 |
1967年 | 4篇 |
1966年 | 4篇 |
1939年 | 3篇 |
排序方式: 共有720条查询结果,搜索用时 15 毫秒
21.
R. Appels J. P. Gustafson C. E. May 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1982,63(3):235-244
Summary Although Giemsa C-banding techniques have been used extensively for assaying cereal heterochromatin, a more specific technique for analyzing cereal heterochromatin has been developed recently with the isolation of DNA sequences present in heterochromatin and their employment in in situ hybridization to cereal chromosomes. A number of triticales were examined for the occurrence of modified rye chromosomes using the in situ hybridization technique. With a heterogeneous sequence probe the amount of rye heterochromatin appears to be relatively constant in wheat backgrounds but when a specific sequence probe was employed variation was observed. Whether this variation reflects polymorphism in rye or whether it is a result of adaption of the rye genome to coexistence with the wheat genome in triticales is discussed. — The triticale Rosner was examined in detail and it was established that the rye chromosome 2R had been replaced by the wheat chromosome 2D. 相似文献
22.
The effect of neurotensin on submaximally-stimulated hepatobiliary and pancreatic secretion was studied in 6 healthy subjects. An intravenous infusion of neurotensin 1.4 ± 0.3 pmol/kg/min, designed to reproduce plasma neurotensin immunoreactivity levels within the physiological range, produced a significant increase in pancreatic bicarbonate output. Plasma concentrations of pancreatic polypeptide rose by 83 ± 16 pmol/l and were associated with a small reduction in trypsin, but no significant change in bilirubin outputs. 相似文献
23.
24.
25.
26.
27.
28.
AB Zarafi AM Emechebe AD Akpa O Alabi 《Archives Of Phytopathology And Plant Protection》2013,46(4):261-268
Pearl millet downy mildew (DM) incidence, severity and yield losses of two pearl millet varieties (local and improved) due to the disease were determined in the field. Significant differences in the disease incidence and severity were recorded in the plots sown with metalaxyl-treated seeds and those sown with non-treated seeds, indicating the efficacy of the fungicide on the fungus. Yield losses due to non-treatment of seeds with metalaxyl was 40.88 and 45.39% in a local variety and 43.00 and 18.60% in an improved variety in the 2000 and 2001 cropping seasons respectively. Significant differences between plots sown with metalaxyl-treated and those sown with non-treated seeds were obtained for other yield components such as 1000-grains weight, panicle length and weight. 相似文献
29.
30.