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11.
The total contents of PAHs, organic polar fractions and 14 major hydrocarbons containing 3–6 aromatic rings as well as heavy metal contents were determined in sewage sludges from highly industrialized (Upper Silesia), agricultural and recreational regions of Poland. Sludges from the industrial region showed markedly increased concentrations of all the organic micropollutants and 2–10 times higher levels of the following heavy metals: Pb, Cd, Cr, Cu, Fe, Zn, Ni, Mn and Co. The levels, however, did not exceed the Polish as well as European Economic Community limit values, which renders all the sludges applicable to land and some of them suitable for utilization on agricultural soils.  相似文献   
12.
In this report, we presented the profile of polyphenolic substances in flowers, leaves, stalk and roots of Fagopyrum tataricum estimated by using RP–UHPLC–ESI-MS equipment (reversed-phase ultra-high-performance liquid chromatography electrospray ionisation mass spectrometry). The neutral detergent fibre, acid detergent fibre, acid detergent lignin, cellulose and hemicellulose were also determined. Flowers, leaves, stalk and roots showed varying levels of dietary fibre and polyphenols. The highest content of neutral and acid detergent fibre were found in the roots (63.92 and 45.45% d.m., respectively) while the most rich in phenolic compounds were flowers (4.8 mg/1 g d.m.). Root and stalk contained the highest level of cellulose, 38.70 and 25.57% d.m., respectively. Among the investigated polyphenolic substances such as: 2,6-dihydroxybenzoic acid, 3,4-dihydroxybenzoic acid, 3,5-dihydroxybenzoic acid, 4-hydrobenzoic acid, caffeic acid, catechin, chlorogenic acid, fagopyrin, ferulic acid, myricetin, gallic acid, isovanilic acid, isovitexin, kaempferol, luteolin, p-coumaric acid, procyanidin B2, quercetin, quercetin 3-D galactoside, rutin, syringic acid and vitexin, we observed that the contents of rutin and chlorogenic acid were the highest. We found some correlation between dietary fibre fractions and individual phenolic substances. The levels of acid detergent fibre (ADF), cellulose and hemicellulose were negatively correlated with isovitexin, kaempferol, vitexin, fagopyrin, caffeic acid and procyanidin B2 content. In this investigation, two solvents (water and methanol) were estimated regarding their extraction efficiency of phenolic compounds. Taking these results into consideration, we recommend using methanol as the extractor to isolate chlorogenic acid, fagopyrin, kaempferol, procyanidin B2, quercetin, quercetin 3-D-galactoside, rutin, vitexin, and water for other investigated polyphenolic substances obtained from Fagopyrum tataricum.  相似文献   
13.
Journal of Plant Diseases and Protection - Plants induce volatile organic compounds (VOCs) after pathogen infection and exposure to a neighbouring infected plant. In a greenhouse, we measured VOCs...  相似文献   
14.
This study analyses the variability of key yield components, the content of protein and crude fat in grain and the fatty acid composition of 50 spring accessions of Triticum monococcum, Triticum dicoccum and Triticum spelta of various origins. The average protein content of the grain of T. monococcum was 20.8%, of T. dicoccum 19.7%, and of spelt 17.0%. The crude fat content of T. monococcum grain (2.7%) was significantly higher compared with T. spelta (2.4%) and T. dicoccum (2.3%). In crude fat, fatty acids C18:2, C18:1 and C16 predominated. T. spelta was characterised by the highest concentrations of C18:2 and C16 (55.89% and 18.77% respectively), while T. monococcum had the highest content of C18:1 (26.35%). The structure of analysed fatty acids proved to be highly desirable in this species. A discriminant analysis performed separately for five variables: protein and fat content and three biometrical characters and separately for fatty acid composition enabled three Triticum species to be distinguished. These species also differed significantly with respect to the C18:1/C16 ratio which was equal to 1.78, 1.06, 1.47 and 0.99 in T. monococcum, T. dicoccum, T. spelta and Triticum aestivum respectively.  相似文献   
15.
The aim of the study was to evaluate the influence of inulin supply to high‐fat diet rich in saturated fatty acids (SFA) on pork quality and profile of sarcoplasmic protein in drip loss. At 50 days of age, twenty cross‐bred pigs (gilts) were randomly allotted to four groups: the control (C) group fed a standard diet, and three experimental (D1, D2 and D3) groups fed a high‐fat diet rich in SFA. Moreover, pigs from the groups D2 and D3 consumed an extra inulin supply (7% of daily feed intake) from 85 to 120 days of age (for 5 weeks) and from 50 to 120 days of age (for 10 weeks) respectively. The addition of inulin to the diet reduced meaty odour and flavour significantly, improved tenderness and overall sensory quality of pork and additionally influenced ultimate pH, L* colour parameter, lactate level and protein content in meat. The diets also affected the profile of sarcoplasmic proteins. Significant effects were observed for the following enzymes—PK/PGI (pyruvate kinase/phosphoglucose isomerase) and ALD (aldolase), which are related to the intensity of post‐mortem glycolysis. Presented data indicate that long‐term inulin supply to high‐fat diet has a positive effect on technological and sensory quality as well as protein profile of pork.  相似文献   
16.
The structures of two previously unknown sesquiterpene alcohols of the potato (Solanum tuberosum) were assigned. The potato alcohols were obtained by steam-distillation, preparative column chromatography, and separation into fractions by HPLC on a silica gel column. The fractions were studied by GC-FID, GC-MS, and NMR spectroscopy. The potato sesquiterpene alcohols were identified as kunzeaol (6-alpha-hydroxygermacra-1(10),4-diene) and ledol. These two compounds were used in feeding tests with larvae and beetles of the Colorado potato beetle (Leptinotarsa decemlineata Say). In a bioassay, kunzeaol was found to act as a feeding attractant for the beetles.  相似文献   
17.
The aim of this study was to demonstrate the effect of auto-vaccine therapy on selected properties of Staphylococcus aureus strains, isolated from milk of cows with subclinical mastitis. The experiment was based on auto-vaccines which were prepared from S. aureus strains isolated from 16 cows. S. aureus strains isolated from cows on the 7th, 21st and 35th day following auto-vaccination, were analyzed phenotypically and genotypically. The isolated strains represented 17 biotypes all belonging to one clonal type. Increases of new biotypes of S. aureus were detected on the 35th day of therapy. Among 48 re-isolated strains, 18.75% (9/48) revealed single and 12.50% (6/48) multiple phenotypical changes. The present study demonstrated that during auto-vaccine therapy, S. aureus strains can change phenotypically, pointing out the necessity for using precise diagnostic methods, that would make possible a better assessment of the used therapy.  相似文献   
18.
19.
Alterations in some physiological processes in source leaves of sugar beet—such as chlorophyll and carbohydrate concentrations, stomatal conductance, rate of net photosynthesis and transpiration, and activity of the photosynthetic apparatus during root interaction with Aphanomyces cochlioides, were investigated. The influence of time of infection on plant health, yield quality and quantity was also examined. Plants were infected at different times of their growth period: on the sowing day and 4 or 8 weeks after sowing. A variation treatment, with non-pelleted seeds infected on the sowing day, was also analyzed. The experiment showed that development of disease symptoms depends on the time of infection and seed protection. A significant root yield decrease was observed in case of late infection, as compared to the yield of plants infected on the sowing day. The fresh weight of leaves was significantly increased where there was late infection. The infected plants showed a lower content of K+, Na+ and α-amino-N than did the controls. Infection by A. cochlioides induced chlorophyll degradation mostly in older leaves with the occurrence of natural senescence processes. Chlorophyll fluorescence parameters indicated that the photosynthetic apparatus of younger leaves was more sensitive to pathogen infection, when compared to older ones. The photochemical efficiency of photosystem II was reduced in young leaves mainly due to disturbance of the water-splitting system. In plants grown from non-pelleted seeds a strong impairment of PSII was observed only in those leaves which developed during early pathogen infection. In young leaves of plants infected in the fourth week after sowing, inhibition of the rate of net photosynthesis was correlated with the increase in intercellular CO2 concentration, indicating some disturbance in the carbon assimilation phase. In mature leaves of late infected plants the reduction of photosynthesis net rate was associated with a decrease of stomatal conductance and an increase of diffusion resistance to CO2 and H2O, which was also the cause of the transpiration rate inhibition. When the leaves developed during early infection, an increase of specific leaf weight and accumulation of carbohydrates was observed. In mature leaves of non-protected plants infected on the sowing day, the recovery of all physiological processes was observed together with a diminution of disease symptoms.  相似文献   
20.
Total concentration of lead and its individual partitioning, i.e. exchangeable, adsorbed, organically bound, carbonate, sulfide and residual have been assayed in the bottom sediment of Rybnik reservoir applying AAS. The contribution of particular fractions to the total lead concentration was as follows: carbonates (37%) > sulfides (28%) > residual (14%) > adsorbed (10%) > exchangeable (8%) > organic bonds (3%). The multiple regression analysis applied led to the conclusion that the increase in lead content in the bottom sediment resulted from an increase in poorly mobile forms, notably carbonates.  相似文献   
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