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21.
Lech Szajdak Irena yczyska‐Baoniak Teresa Meysner Andrzej Blecharczyk 《植物养料与土壤学杂志》2004,167(5):562-567
We investigated the varying concentrations of bound amino acids in humic acids (HA) extracted from soils under both crop rotation and continuous cropping of rye. The experiment was created in 1957. Since then, winter rye had been grown continuously and also the sequence of the 7 yr rotation had been started: potato, spring barley, alfalfa, alfalfa, oil seed rape, winter rye, and winter rye. Soils were fertilized with NPK and manure. Continuous cropping of rye increased total acidity of soils and the contents of carboxylic and phenolic groups in HA. The total amounts of the bound amino acids in HA from soils under crop rotation were higher than from continuous cropping of rye. Fertilization with NPK increased the contents of bound amino acids more than manure. Neutral amino acids dominated in all samples of HA, and basic amino acids had the lowest concentrations. In both types of cultivation, glutamic acids, glycine, alanine, valine, and lysine dominated. The proline contents in HA from continuous rye cropping were higher than in HA from soils under crop rotation. The concentrations of β‐alanine and lysine were higher in HA from crop rotation indicating a higher microbial biomass since these compounds are typical constituents of bacteria cell walls. 相似文献
22.
Picerno P Mencherini T Lauro MR Barbato F Aquino R 《Journal of agricultural and food chemistry》2003,51(22):6423-6428
An extract of Xanthosoma violaceum leaves was subjected to a polyphenol profile determination, including total polyphenols, and antioxidant activity evaluation. Analysis of the extract resulted in the isolation of a new flavone C-glycoside, apigenin 6-C-beta-D-glucopyranosyl-8-C-beta-D-apiofuranoside (1), as well as known flavone C-glycosides, including vitexin (2), isovitexin (3), isovitexin 4'-O-rhamnopyranoside (4), apigenin 6-C-[beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranoside] (5), and apigenin 6,8-diC-beta-D-glucopyranoside (6). The antioxidant activity of the extract was assessed by means of two different in vitro tests: bleaching of the stable 1,1-diphenyl-2-picrylhydrazyl radical (DPPH test) and peroxidation induced by the water-soluble radical initiator 2,2'-azobis(2-amidinopropane) hydrochloride, on mixed dipalmitoylphosphatidylcholine/linoleic acid unilamellar vesicles (LP-LUV test). In both tests used, the extract and a fraction II showed a significant antioxidant/free-radical scavenging effect (fraction II, EC(50) = 11.6 microg/mL) in comparison to alpha-tocopherol (EC(50) = 10.1 microg/mL). 相似文献
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Andresen U Kietzmann M Andresen P 《Berliner und Münchener tier?rztliche Wochenschrift》1999,112(10-11):400-406
The systemic tolerance of a solution of calcium aspartate and magnesium aspartate was studied in 7 cows. Intravenously administered dosages of 500 ml per cow were well tolerated. A twofold increase of the serum calcium concentration was measured. In 2 cows which were treated with 1000 ml of the solution a threefold increased calcium concentration and heart arrhythmia were found. The clinical efficacy of the solution was demonstrated in a study with 44 hypocalcemic cows. A long lasting increase of the serum calcium as well as an enhanced phosphorus concentration were measurable. In conclusion, the calcium-magnesium-aspartate solution seems to be an efficacious and well tolerated alternative for the treatment of hypocalcemia in cows. 相似文献
25.
Salceda Fernández-Barredo Carolina Galiana Angel García Santiago Vega María Teresa Gómez María Teresa Pérez-Gracia 《Journal of veterinary diagnostic investigation》2006,18(5):462-465
The aim of this study was to determine at which production stages hepatitis E virus (HEV) is shed by the highest number of pigs and to estimate the relative risk associated with each stage. For this purpose, 146 fecal samples of pigs from 21 farms were studied. In addition, 1 sample from the manure ditch and another sample of drinking water, collected directly from the trough located in the pen, were taken from 16 farms. HEV RNA was detected in fecal samples from 34 pigs (23.29%). The production stages in which most pigs excreted HEV were weaners (41.7%) and pigs in the first month of feeding (60%). The results of the statistical analysis showed that the principal significant risk stage in HEV shedding was the first month of feeding (odds ratio [OR] 19.5, 95% CI 3.59-106.07, P = 0.001) followed by the weaners stage (OR 9.3, 95% CI .78-48.42, P = 0.008). In 8 out of 16 farms tested (50%) HEV RNA was detected in raw manure and in the water trough of only 1. Detection of HEV in manure ditches raises the concern of how to deal with manure of swine origin, because it is used as soil fertilizer. 相似文献
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European policies and instruments such as the Common Agricultural Policy (CAP) and many instruments for nature and landscape
conservation in Europe have for some decades been dominated by centralisation and standardisation. This paper shows that this
has led to the neglect of contextual and place-related approaches and an unnecessarily high degree of over-simplification.
Recently, as a reaction to this over-simplification, diversity and specific character has been particularly stressed in many
European and national strategies for rural landscapes and conservation, but the processes of simplification still continue.
Using examples from mixed agriculture and forestry landscapes in Portugal, Slovenia and Sweden, this paper aims to contribute
to understanding the gap between centrally defined strategies for rural landscapes and awareness and management practices
at local level. The three countries are situated at the outer fringes of Europe, and are complementary with their different
degrees of urbanisation, forest distribution and tree-richness in the agricultural landscapes. Furthermore, the aim is to
show how local landscape management is driven and to identify factors contributing to a better use of public policies through
a participatory process with visions for the future. Systems of landscape classifications such as landscape character assessment
often recognise the specific character of these landscapes, but have so far achieved very little for the preservation of their
locally specific values, nor have they contributed to the development and the creation of new visions for future management.
Such systems could contribute much more if they could be opened to adaptation on a more local scale in communication-led management
planning. 相似文献
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30.
Zaffaroni E Teresa Manfredi M Citterio C Sala M Piccolo G Lanfranchi P 《Veterinary parasitology》2000,90(3):221-230
Abomasums from 641 alpine wild ruminants representing five different species (Cervus elaphus, Capreolus capreolus, Rupicapra rupicapra, Capra ibex, Ovis musimon) and from 19 domestic sheep (Ovis aries) from alpine areas were examined in order to investigate the host-specificity of abomasal helminths. Nine out of 20 helminth species were found in at least five different host species. A discriminant analysis was able to significantly discriminate the hosts on the basis of their helminth community composition with the exception of O. musimon and O. aries. Based on the correlation between each variable represented by helminth species with the most explanatory discriminant axis, it was possible to classify helminths into specialists and generalists. Specialists are represented by the dominant species in a community of an host species or family while generalists appear in the communities of many different hosts as intermediate species. Due to the pathogenic potential of some of these generalist species (i.e. Haemonchus contortus, Trichostrongylus axei) and their ability to adapt easily to the conditions found in several different hosts, they appear to be the most important from a sanitary point of view. 相似文献