全文获取类型
收费全文 | 130篇 |
免费 | 5篇 |
国内免费 | 1篇 |
专业分类
林业 | 8篇 |
农学 | 4篇 |
基础科学 | 4篇 |
18篇 | |
综合类 | 14篇 |
农作物 | 5篇 |
水产渔业 | 9篇 |
畜牧兽医 | 60篇 |
园艺 | 5篇 |
植物保护 | 9篇 |
出版年
2023年 | 2篇 |
2021年 | 1篇 |
2020年 | 5篇 |
2019年 | 4篇 |
2018年 | 7篇 |
2017年 | 5篇 |
2016年 | 5篇 |
2015年 | 6篇 |
2014年 | 5篇 |
2013年 | 5篇 |
2012年 | 4篇 |
2011年 | 16篇 |
2010年 | 6篇 |
2009年 | 12篇 |
2008年 | 2篇 |
2007年 | 11篇 |
2006年 | 7篇 |
2005年 | 4篇 |
2004年 | 1篇 |
2003年 | 1篇 |
2002年 | 3篇 |
2001年 | 3篇 |
1999年 | 3篇 |
1997年 | 1篇 |
1990年 | 1篇 |
1989年 | 2篇 |
1988年 | 2篇 |
1987年 | 3篇 |
1984年 | 2篇 |
1983年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1973年 | 1篇 |
1972年 | 1篇 |
排序方式: 共有136条查询结果,搜索用时 31 毫秒
11.
Twenty-one strains of Nocardia farcinica isolated from cattle with bovine farcy in the Sudan were examined to determine their taxonomic relationships. The strains had morphological, cultural and physiological properties of Nocardia, but exhibited some variations of minor taxonomic importance. All strains contained lipids characteristic of nocardiae (LCN-As) and all except two were found by immunodiffusion tests to be serologically related to each other, to N asteroides but not to Mycobacterium tuberculosis nor M bovis. Consequently, these organisms were regarded as true members of the genus Nocardia. 相似文献
12.
13.
14.
Cihan Ka?ar Kadir ?zcan ?smet Tak?? Kutlay Gürbulak Hasan ?zen Musa Karaman 《Journal of veterinary science (Suw?n-si, Korea)》2008,9(4):429-431
Congenital malformations with multiple anomalies have been described infrequently in the veterinary literature. A stillborn male crossbred lamb with diprosopus, craniorachischisis, and arthrogryposis was examined macroscopically and histopathologically in this study. The left head was smaller than the right head. Micrencephaly, agnathia, and a rudimentary tongue, which was adherent to the palate, were present in the left head. Micrencephaly, brachygnathia superior, and cleft palate were present in the right head. Cerebellar agenesis and spinal cord hypoplasia were observed. The cerebrums and the spinal cord were covered with a tapering membranous structure. Neural and dermal tissues were noted to intervene upon microscopic examination of this structure. Disorganization of neurons was observed in both cerebrums, though it was more severe in the left one. This case demonstrates many congenital defects occurring together in a lamb. 相似文献
15.
16.
烟粉虱经济阈值的研究 总被引:3,自引:0,他引:3
研究了烟粉虱在黄瓜上的经济损害水平和经济阈值。黄瓜幼苗4叶期时,烟粉虱的经济损害水平为9.3159%;烟粉虱的经济阈值为每株黄瓜有烟粉虱成虫18.4474头,即平均每片黄瓜叶有成虫4.6119头。 相似文献
17.
18.
W. Sun H. Chang K. Tsunoda H.H. Musa Z.P. Yang Y.H. Ma W.J. Guan 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2010,127(4):308-317
The genetic diversity and phylogenetic survey of native sheep breeds in the eastern and southern Central Asia were assessed in the present study. The clustering, principal components, structure and F statistics all demonstrate that the native sheep breeds in these regions be classified into two genetic groups: Mongolia‐Tibetan sheep group and South‐Southeast Asia sheep group. The Mongolia sheep group and the Tibetan sheep group had a certain degree of gene communication from the ancient times. In the present study we demonstrated that the Chinese native sheep populations belonged to Mongolia‐Tibetan sheep group. However, the relationships among the sheep populations in Mongolia sheep group in China were not closely related to the geographical distance among sheep populations. 相似文献
19.
New withanolides from Mandragora officinarum: First report of withanolides from the Genus Mandragora
Two new withanolides named mandragorolide A (1) and mandragorolide B (2) were isolated from the MeOH extract of the whole plant of Mandragora officinarum of Jordanian origin, along with five known withanolides namely larnaxolide A (3), withanolide B (4), datura lactone 2 (5), withanicandrin (6) and salpichrolide C (7). Compound 3 has been reported only once before, from the leaves of Larnax glabra. This is the first report of withanolides of different biogenetic types from the genus Mandragora. Isolation of known fatty compounds, coumarins, sterols and tropane alkaloids was also achieved in this study. 相似文献
20.
Least squares support vector machine for modeling daily reference evapotranspiration 总被引:3,自引:0,他引:3
Ozgur Kisi 《Irrigation Science》2013,31(4):611-619
The accuracy of a least square support vector machine (LSSVM) in modeling of reference evapotranspiration (ET0) was examined in this study. The daily weather data, solar radiation, air temperature, relative humidity and wind speed of two stations, Glendale and Oxnard, in southern district of California, were used as inputs to the LSSVM models to estimate ET0 obtained using the FAO-56 Penman–Monteith equation. In the first part of the study, LSSVM estimates were compared with those of the following empirical models: Priestley–Taylor, Hargreaves and Ritchie methods. The comparison results indicated that the LSSVM performed better than the empirical models. In the second part of the study, the LSSVM results were compared with those of the conventional feed-forward artificial neural networks (ANN). It was found that the LSSVM models were superior to the ANN in modeling ET0 process. 相似文献