全文获取类型
收费全文 | 77篇 |
免费 | 2篇 |
专业分类
林业 | 14篇 |
农学 | 1篇 |
31篇 | |
综合类 | 8篇 |
农作物 | 2篇 |
水产渔业 | 3篇 |
畜牧兽医 | 15篇 |
园艺 | 4篇 |
植物保护 | 1篇 |
出版年
2021年 | 4篇 |
2019年 | 3篇 |
2018年 | 2篇 |
2017年 | 3篇 |
2016年 | 3篇 |
2015年 | 2篇 |
2014年 | 2篇 |
2013年 | 7篇 |
2012年 | 5篇 |
2011年 | 5篇 |
2010年 | 3篇 |
2009年 | 2篇 |
2008年 | 3篇 |
2007年 | 6篇 |
2006年 | 3篇 |
2005年 | 1篇 |
2004年 | 2篇 |
2002年 | 1篇 |
2001年 | 1篇 |
2000年 | 1篇 |
1999年 | 2篇 |
1995年 | 1篇 |
1994年 | 2篇 |
1989年 | 1篇 |
1979年 | 1篇 |
1978年 | 2篇 |
1972年 | 1篇 |
1971年 | 2篇 |
1970年 | 2篇 |
1969年 | 1篇 |
1968年 | 1篇 |
1945年 | 1篇 |
1936年 | 1篇 |
1932年 | 1篇 |
1929年 | 1篇 |
排序方式: 共有79条查询结果,搜索用时 15 毫秒
61.
Martín-Hernández C Bénet S Obert L 《Journal of agricultural and food chemistry》2008,56(12):4348-4351
Five methods using aqueous/organic solvents for the separation of proteins from oils were compared. The extraction with acetone-hexane followed by amino acid analysis was found to be the most suitable method for isolation and quantification of proteins from oils. The detection limit of the method was 0.18 mg protein/kg oil, and the quantification limit was 0.6 mg protein/kg. The relative repeatability limit for samples containing 1-5 mg protein/kg sample was 27%. The protein recovery ranged between 68 and 133%. Using this method, the protein content of 14 refined and nonrefined oils was determined. In none of the refined oils were proteins detected, whereas the protein content of the unrefined oils ranged between undetectable in extra virgin olive oil to 11 mg/kg in rapeseed oil. With sodium dodecyl sulfate-polyacrylamide gel electrophoresis in combination with silver staining, many protein bands were visible in the unrefined soy, olive, peanut, and rapeseed oil samples. Proteins bands were not obtained from the refined fish oil. In the other refined oil samples, a few proteins bands could be visualized. Two protein bands with apparent molecular molecular masses of 58 and 64 kDa were always observed in these oils. 相似文献
62.
Lukáš Hlisnikovský Michal Hejcman Eva Kunzová Ladislav Menšík 《Archives of Agronomy and Soil Science》2019,65(2):152-163
Triticum monococcum L., Triticum dicoccum Schrank and Triticum spelt L. nowadays offer an alternative to Triticum aestivum L. We analyzed grain and straw yield, yielding parameters, chemical composition and bakery quality of these species and compared them with modern T. aestivum at three sites with different soil-climate conditions. The average grain yield varied from 0.41 t ha?1 (T. monococcum) to 5.17 t ha?1 (T. aestivum), straw yield varied from 1.50 t ha?1 (T. dicoccum) to 5.83 t ha?1 (T. aestivum). The yielding parameters and chemical composition of the grain were significantly influenced by soil-climate conditions and wheat species. The highest average crude protein content was recorded in T. spelta (20.55%), while the lowest in T. aestivum (11.20%). The Zeleny’s sedimentation test ranged from 9.0 ml (T. monococcum) to 34.5 ml (T. aestivum) and the value of the Gluten index varied from 7.45 (T. dicoccum) to 89.75 (T. aestivum). According to the results, ancient wheat species provides lower grain and straw yields, higher protein content and mineral concentrations. Concentration of proteins and grain’s baking quality strongly depends on wheat species and soil-climate conditions. 相似文献
63.
A comprehensive phylogeny of beetles reveals the evolutionary origins of a superradiation 总被引:1,自引:0,他引:1
Hunt T Bergsten J Levkanicova Z Papadopoulou A John OS Wild R Hammond PM Ahrens D Balke M Caterino MS Gómez-Zurita J Ribera I Barraclough TG Bocakova M Bocak L Vogler AP 《Science (New York, N.Y.)》2007,318(5858):1913-1916
Beetles represent almost one-fourth of all described species, and knowledge about their relationships and evolution adds to our understanding of biodiversity. We performed a comprehensive phylogenetic analysis of Coleoptera inferred from three genes and nearly 1900 species, representing more than 80% of the world's recognized beetle families. We defined basal relationships in the Polyphaga supergroup, which contains over 300,000 species, and established five families as the earliest branching lineages. By dating the phylogeny, we found that the success of beetles is explained neither by exceptional net diversification rates nor by a predominant role of herbivory and the Cretaceous rise of angiosperms. Instead, the pre-Cretaceous origin of more than 100 present-day lineages suggests that beetle species richness is due to high survival of lineages and sustained diversification in a variety of niches. 相似文献
64.
65.
Beata Mal
ekov Monika Halnov Zlatana Sulínov Ladislav Molnr Petra Ravaszov Jozef Adam Milo Haln Igor Valocký Milan Baranovi
《Research in veterinary science》2010,89(3):358-361
The presence of antibodies against Encephalitozoon cuniculi (E. cuniculi) and Encephalitozoon intestinalis (E. intestinalis) was examined in 215 samples from humans and in 488 samples from five different species of domestic and companion animals in Slovakia. The 215 human samples and samples from 90 swine, 123 non-infected cattle (cattle), 24 cattle infected with bovine leukosis virus (BLV-positive cattle), 140 sheep and 111 dogs were examined by the enzyme-linked immunosorbent assay (ELISA). Samples with serum titres 1:200 or higher were considered as positive. Specific anti-E. cuniculi antibodies were found in humans (0.9%), swine (52%), cattle (2%), sheep (9%) and dogs (15%) except for the BLV-positive cattle at the titre of 1:200. The titre of 1:400 was detected only in humans (0.5%). The presence of specific anti-E. intestinalis antibodies at the titre of 1:200 was confirmed in humans (6%), swine (51%), cattle (11%), BLV-positive cattle (13%) and dogs (6%) but not in sheep. The anti-E. intestinalis antibodies reached the 1:400 in humans (1%), swine (4%) and BLV-positive cattle (17%). The presence of specific anti-E. intestinalis antibodies at the titre of 1:600 was observed only in one swine (1%). Significant differences were observed in animals at titres 1:200 and 1:400 (chi-squared test: p < 0.0001) for both pathogens and in humans only for E. cuniculi at the titre of 1:400 (chi-squared test: p < 0.0075). 相似文献
66.
Redistribution of organic pollutants in river sediments and alluvial soils related to major floods 总被引:2,自引:5,他引:2
Klara Hilscherova Ladislav Dusek Vratislav Kubik Pavel Cupr Jakub Hofman Jana Klanova Ivan Holoubek 《Journal of Soils and Sediments》2007,7(3):167-177
Background, Aims, and Scope More frequent occurrence of stronger floods in Europe as well as in other parts of the world in recent years raises major
concern about the material damages, but also an important issue of contamination of the affected areas through flooding. The
effects of major floods on levels and distribution of contamination with hydrophobic organic pollutants were examined from
the continuous set of data for floodplain soils and sediments from a model industrial area in the Czech Republic where a 100-year
flood occurred in 1997. The goal of this study was to evaluate the risk related to contamination associated with such extensive
natural events and characterize the spatial and temporal distribution and dynamics of pollutants related to a major flooding
shortly after the floods and also in the time period several years after floods.
Methods Sediments and alluvial soils from fourteen sites each were repeatedly sampled during the period from 1996 until 2005. The
sampling sites represented five regions. Collected top-layer sediment and soil samples were characterized and analyzed for
hydrophobic organic pollutants PCBs, OCPs and HCB using GC-ECD and PAHs using a GC-MS instrument. Spatial and temporal differences
as well as the relative distribution of the pollutants were examined in detail by statistical analysis including multivariate
methods with special emphases placed on the changes related to floods.
Results The organic pollutants levels in both alluvial soils and sediments exceeded the safe environmental limits at numerous sites.
Pollutants concentrations and relative distribution as well as organic carbon content in both sediment and floodplain soils
were significantly affected by the flooding, which resulted in a decrease of all studied contaminants in sediments and significant
rise of the PAH pollution in the flooded soils. There was a unique and highly conserved PAH pattern in soils regardless of
the floods and greater changes in PAH pattern in sediments related to floods. The relative distribution of individual PAHs
reflected a combustion generated PAH profile. PAH levels in the river sediments rose again at the sites with continuous sources
several years after floods.
Discussion The results showed different dynamics of PAHs and PCBs during the floods when PAHs were redistributed from the sediments to
alluvial soils while PCBs have been washed out of the study regions. The data reveal longer contamination memory and consistent
contamination pattern in soils, whereas sediments showed more dynamic changes responding strongly to the actual situation.
The stable PAH pattern within the regions also indicates that a relative amount of all compounds is comparable across the
samples and, thus, that the sources at different sites have similar character.
Conclusions Sediments have the potential to function as a secondary source of contamination for the aquatic ecosystem, but also for the
floodplain soils and other flooded areas. The floods served as a vector of PAHs contamination from sediments to soils. The
reloading of river sediments in time, namely with PAHs, due to present sources increases their risk as a potential source
in the next bigger flood event both to the downstream river basin and affected alluvial soils.
Recommendations and Perspectives The results stress the importance of including the floodplain soil contamination in the risk assessment focused on flood effects.
Floodplain soils have stable long-term environmental memory related to contamination levels, pattern and distribution, whereby
they can provide relevant information on the overall contamination of the area. The sediments will continue to serve as a
potential source of contaminants and alluvial soils as the catchment media reflecting the major flood events, especially until
effective measures are taken to limit contamination sources.
ESS-Submission Editor: Dr. Henner Hollert (Hollert@uni-heidelberg.de)
This article is openly accessible! 相似文献
67.
68.
69.
70.
Tereza Novakova Tomas Matys Grygar Ondrej Babek Martin Famera Martin Mihaljevic Ladislav Strnad 《Journal of Soils and Sediments》2013,13(2):460-473