全文获取类型
收费全文 | 157篇 |
免费 | 8篇 |
专业分类
林业 | 18篇 |
农学 | 3篇 |
80篇 | |
综合类 | 12篇 |
农作物 | 4篇 |
水产渔业 | 6篇 |
畜牧兽医 | 25篇 |
园艺 | 1篇 |
植物保护 | 16篇 |
出版年
2023年 | 1篇 |
2022年 | 1篇 |
2021年 | 3篇 |
2019年 | 5篇 |
2018年 | 3篇 |
2017年 | 2篇 |
2016年 | 8篇 |
2015年 | 4篇 |
2014年 | 4篇 |
2013年 | 9篇 |
2012年 | 3篇 |
2011年 | 4篇 |
2010年 | 4篇 |
2009年 | 5篇 |
2008年 | 14篇 |
2007年 | 17篇 |
2006年 | 9篇 |
2005年 | 7篇 |
2004年 | 5篇 |
2003年 | 8篇 |
2002年 | 11篇 |
2001年 | 3篇 |
2000年 | 4篇 |
1999年 | 3篇 |
1997年 | 4篇 |
1996年 | 2篇 |
1995年 | 5篇 |
1994年 | 2篇 |
1993年 | 2篇 |
1990年 | 2篇 |
1989年 | 2篇 |
1982年 | 1篇 |
1979年 | 1篇 |
1978年 | 2篇 |
1977年 | 1篇 |
1974年 | 1篇 |
1965年 | 1篇 |
1959年 | 1篇 |
1950年 | 1篇 |
排序方式: 共有165条查询结果,搜索用时 46 毫秒
91.
92.
Rehfus Alexandra Matusinsky Pavel Strobel Dieter Bryson Rosie Stammler Gerd 《植物病害和植物保护杂志》2019,126(5):447-459
Journal of Plant Diseases and Protection - Ramularia collo-cygni is a devastating plant pathogen of barley with an increasing importance in Europe and several other barley growing regions... 相似文献
93.
94.
Bassereau M Chaintreau A Duperrex S Joulain D Leijs H Loesing G Owen N Sherlock A Schippa C Thorel PJ Vey M 《Journal of agricultural and food chemistry》2007,55(1):25-31
The performances of the GC-MS determination of suspected allergens in fragrance concentrates have been investigated. The limit of quantification was experimentally determined (10 mg/L), and the variability was investigated for three different data treatment strategies: (1) two columns and three quantification ions; (2) two columns and one quantification ion; and (3) one column and three quantification ions. The first strategy best minimizes the risk of determination bias due to coelutions. This risk was evaluated by calculating the probability of coeluting a suspected allergen with perfume constituents exhibiting ions in common. For hydroxycitronellal, when using a two-column strategy, this may statistically occur more than once every 36 analyses for one ion or once every 144 analyses for three ions in common. 相似文献
95.
Nuernberg K Dannenberger D Ender K Nuernberg G 《Journal of agricultural and food chemistry》2007,55(3):598-602
Four different methods for the methylation of conjugated linoleic acid isomers (CLA) in ruminant lipids were compared by silver ion (Ag+) HPLC. The combination of base-catalyzed methods followed by an acid-catalyzed method with BF3/MeOH was tested under different temperatures (room temperature and at 60 degrees C), along with based-catalyzed methylation with NaOCH3 and methylation with BF3/MeOH after saponification with NaOH. The comparison among these four methods was done on muscle and adipose tissue samples from bulls. The repeatability theta of the combined base- and acid-catalyzed methylation (NaOCH3/BF3) at ambient temperature for 20 min and at 60 degrees C for 10 min was most suitable for the quantitative Ag+-HPLC analysis of CLA isomers. At 60 degrees C the combined methods supplied the highest concentrations of most CLA isomers. The base-catalyzed methylation and the saponification followed by BF3/MeOH methylation for 5 min generated significantly lower concentrations for most CLA isomers compared to the combined methods. 相似文献
96.
Ayman El Behiry Gerd Schlenker Istvan Szabo Uwe Roesler 《Journal of veterinary science (Suw?n-si, Korea)》2012,13(2):153-161
Sensitivity to commercial teat dips (nonoxinol-9 iodine complex and chlorhexidine digluconate) of 56 Staphylococcus (S.) aureus strains isolated from quarter milk samples of various German dairy herds treated with different teat dipping schemes was investigated in this study. The minimum inhibitory concentration was determined using a broth macrodilution method according to the German Veterinary Association guidelines. The main objective of the current study was to induce in vitro resistance induction of S. aureus to chemical disinfectants. Ten different strains were repeatedly passed ten times in growth media with sub-lethal concentrations of disinfectants. Nine strains showed a significant reduction in susceptibility to the nonoxinol-9 iodine complex but only one strain developed resistance to chlorhexidine digluconate. Stability of the acquired resistance was observed in all S. aureus strains adapted to the nonoxinol-9 iodine complex and chlorhexidine digluconate. In contrast, simultaneous resistance to different antibiotics was not observed in any of the ten investigated S. aureus strains. However, the isolates exhibited a high degree of resistance to penicillin G. Based on these results, resistance of S. aureus to chemical disinfectants may be more likely to develop if the chemicals are used at concentrations lower than that required for an optimal biocidal effect. 相似文献
97.
Dannenberger D Nuernberg G Scollan N Schabbel W Steinhart H Ender K Nuernberg K 《Journal of agricultural and food chemistry》2004,52(21):6607-6615
This study examined the effects of feeding diets rich in either n-3 or n-6 polyunsaturated fatty acids (PUFA) on the fatty acid composition of longissimus muscle in beef bulls. Thirty-three German Holstein bulls were randomly allocated to either an indoor concentrate system or periods of pasture feeding (160 days) followed by a finishing period on a concentrate containing linseed to enhance the contents of n-3 PUFA and conjugated linoleic acids (CLA) in beef muscle. The relative proportion and concentration (mg/100 g fresh muscle) of n-3 fatty acids in the phospholipid and triglyceride fractions were significantly increased (p < or = 0.05) in muscle lipids of pasture-fed bulls. The pasture feeding affected the distribution of individual CLA isomers in the muscle lipids. The proportion of the most prominent isomer, CLA cis-9,trans-11, was decreased from 73.5 to 65.0% of total CLA in bulls fed on concentrate as compared to pasture. The second most abundant CLA isomers were CLA trans-7,cis-9 and CLA trans-11,cis-13 in bulls fed on concentrate and pasture, respectively. Diet had no effect on the concentration of C18:1 trans-11. In contrast, the concentration of the C18:1 trans-13/14, trans-15, and trans-16 isomers in the muscle lipids was up to two times higher in pasture-fed as compared to concentrate-fed bulls. Pasture feeding enhanced the concentration of n-3 fatty acids, but the diet had no effect on the concentration of CLA cis-9,trans-11. 相似文献
98.
Balthasar?QuackEmail author Heinz-Christian?Fründ Heinrich?H?per Gerd?Hamscher 《Journal of Soils and Sediments》2005,5(2):107-111
Background Tetracycline (TC) is one of the most common antibiotics in animal husbandry. Concentrations of up to 200 µg TC kg1 have been found in soils, which have repeatedly received pig manure, and it can be assumed that there is an accumulation in soil. Methods The established methods for chemical analysis of extractable TC in soil employ HPLC-UV or HPLC-MS-MS. These methods are quite expensive and require well-trained laboratory personnel and sophisticated high-technology equipment. For this reason, a German Standard Bioassay (DIN 58940 Part 13) was adjusted and validated in order to establish an alternative low-priced method for monitoring TC contents in soil samples. The tests were conducted with two soils (sand and loamy sand) spiked with TC at 6 concentrations. With this bioassay, TC in soils was analyzed and a simple quantification procedure was established. It will be demonstrated that sand and loamy sand soil properties have an influence on the recoveries of extractable, bioactive TC. Results In the loamy sand soil, less bioactive TC was extracted (1525%) than in the sandy soil (3055%), when tested against the aqueous TC-solution (100%) as a control. These results were confirmed by HPLC- MS-MS analyses. The bioassay was successfully employed in a degradation study in a greenhouse pot experiment.Recommendation It could prove to be expedient to use this bioassay in the assessment of other antibiotics as well. 相似文献
99.
100.
Gerd Hagenow 《Plant foods for human nutrition (Dordrecht, Netherlands)》1974,24(1-2):163-173
Zusammenfassung Die in der antiken Literatur überlieferten Nachrichten über die Verwendung der Zwiebelgewächse als Nahrung und als Heilmittel werden gesammelt, kritisch überprüft, und ihre Weitergabe bis in die Neuzeit wird kurz umrissen. Neben manchem Aberglauben und manchen Kuriositäten enthält dieses Material auch Einsichten, die durch die moderne Wissenschaft bestätigt werden konnten.
The significance of onions (Allium cepa L.) as food and medicine in the antiquity. Empiricism and Superstition
The author studied the ancient literature in order to detect reliable sources on the role of onions as food and medicine. Both empiricism and superstition prevail. This makes it difficult to get the real facts, which allows a comparison with modern findings in research.相似文献