全文获取类型
收费全文 | 933篇 |
免费 | 12篇 |
专业分类
林业 | 61篇 |
农学 | 39篇 |
基础科学 | 4篇 |
213篇 | |
综合类 | 86篇 |
农作物 | 55篇 |
水产渔业 | 72篇 |
畜牧兽医 | 349篇 |
园艺 | 12篇 |
植物保护 | 54篇 |
出版年
2024年 | 18篇 |
2023年 | 7篇 |
2022年 | 11篇 |
2021年 | 28篇 |
2020年 | 30篇 |
2019年 | 31篇 |
2018年 | 26篇 |
2017年 | 26篇 |
2016年 | 27篇 |
2015年 | 22篇 |
2014年 | 32篇 |
2013年 | 62篇 |
2012年 | 62篇 |
2011年 | 73篇 |
2010年 | 42篇 |
2009年 | 36篇 |
2008年 | 55篇 |
2007年 | 55篇 |
2006年 | 48篇 |
2005年 | 44篇 |
2004年 | 33篇 |
2003年 | 25篇 |
2002年 | 26篇 |
2001年 | 6篇 |
2000年 | 6篇 |
1999年 | 5篇 |
1998年 | 3篇 |
1996年 | 6篇 |
1995年 | 6篇 |
1992年 | 4篇 |
1991年 | 4篇 |
1990年 | 5篇 |
1986年 | 3篇 |
1983年 | 5篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1980年 | 2篇 |
1979年 | 3篇 |
1975年 | 3篇 |
1974年 | 3篇 |
1973年 | 5篇 |
1972年 | 3篇 |
1971年 | 2篇 |
1966年 | 3篇 |
1928年 | 2篇 |
1924年 | 2篇 |
1916年 | 3篇 |
1911年 | 2篇 |
1903年 | 2篇 |
1902年 | 2篇 |
排序方式: 共有945条查询结果,搜索用时 0 毫秒
71.
72.
Eva Chroustová 《Veterinary parasitology》1979,5(1):57-64
This report describes experimental infection of Lymnaea (Galba) palustris. (Müller, 1774) snails with Fascioloides magna (Bassi, 1875). Of 725 L. palustris, 400 survived the experimental infection and in 172 (43%) the developmental cycle of the fluke was completed. Free emergence of cercariae was obtained was obtained 68 days after infection. The infectivity of metacercariae thus obtained was demonstrated in guinea-pigs, rabbits and a Cameroon goat. In sheep, the infection produced only changes in the organs, but no flukes could be recovered. Considering that L. palustris are found frequently in natural habitats in Czechoslovakia, they should be considered as possible intermediate hosts for F. magna. 相似文献
73.
74.
With the use of monopolar recordings for averaged evoked responses, detected signals in a vigilance task are associated with a late positive component which is absent for undetected signals as well as nonsignals. Bipolar recordings obscure the late positive component associated with detected signals. The data suggest that the late positive component represents cerebral processes associated with evaluation of unpredictable changes in stimulation. 相似文献
75.
76.
Jana Kalinova Eva Dadakova 《Plant foods for human nutrition (Dordrecht, Netherlands)》2009,64(1):68-74
The aim of the study was to confirm the presence of rutin, one of the most common quercetin glycosides, and other quercetin
derivatives in plants of genus Amaranthus, to investigate the influence of the species and variety on rutin distribution in the plant and content changes during growing
season. The rutin content was determined by micellar electrokinetic capillary chromatography in individual plant parts at
the beginning of the growth, at the flowering stage and at the maturity stage of five Amaranthus species. The total quercetin content was determined by micellar electrokinetic capillary chromatography too. The rutin content
in amaranth ranged from 0.08 (in seeds) to 24.5 g/kg dry matter (in leaves). Comparison of the determined total quercetin
content and the calculated content of quercetin released from rutin did not prove important presence of quercetin or other
quercetin derivatives than rutin. Only amaranth leaves sampled at the maturity stage probably contained quercetin or quercetin
derivatives. Significant differences in the rutin content were established among species and as well varieties. Amaranthus hybrid and A. cruentus were the best sources of rutin. 相似文献
77.
78.
Ritter WE Hill EA Whipple GM Starr MA Trelease W Greely AW 《Science (New York, N.Y.)》1902,16(410):731-739
79.
A 20-year-old gelding presented with a history of acute respiratory distress which began immediately after administration of a mineral oil and water mix, via nasogastric intubation, for treatment of suspected gastrointestinal dysfunction. An initial presumptive diagnosis of acute lipoid pneumonia was made; this was further supported by evidence of arterial hypoxaemia and oxygen desaturation on arterial blood gas analysis, ultrasonographic signs of bilateral ventral lung consolidation and a mixed bronchoalveolar-interstitial lung pattern seen on thoracic radiographs. Despite intensive supportive therapy the horse's condition continued to deteriorate and the decision was made for humane euthanasia. Gross necropsy findings supported the clinical diagnosis of lipoid pneumonia. 相似文献
80.