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Veterinary Research Communications - Hamsters are often chosen as companion animals but are also a group of animals frequently subjected to laboratory tests. As there are no scientific publications...  相似文献   
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The alkylresorcinol content and homologue composition in selected Polish rye and wheat cultivars and selected whole-grain cereal products were determined in this study. Cereal grains and whole-grain cereal products were extracted with acetone, whereas bread types were extracted with hot 1-propanol. The average alkylresorcinol content in tested rye (approximately 1100 mg/kg DM) and wheat (approximately 800 mg/kg DM) grains harvested in Poland was within the range previously reported in Swedish and Finnish samples. The total alkylresorcinol content in tested cereal products available on the Polish market varied from very low levels in barley grain-based foods up to 3000 mg/kg DM in wheat bran. The total alkylresorcinol content in 14 bread samples extracted with hot 1-propanol varied from approximately 100 mg/kg DM in whole bread made with honey up to approximately 650 mg/kg DM in whole-rye bread. Calculated ratios of C17:0 to C21:0 homologues, a useful parameter previously used to distinguish between rye and wheat cereals and their derived products, was about 1.2-1.4 in rye products, about 0.2 in wheat products, and varied between 0.2 and 0.6 in cereal-derived products containing a mixture of whole rye and/or wheat. The data set obtained were subsequently compared using cluster and principal component analysis, which allowed the tested cereal products to be classified into two major groups consisting of whole-rye or whole-wheat products, respectively. On the basis of that approach, mixed cereal products containing rye and wheat bran or whole rye and wheat flour were grouped between those two well-defined clusters. Our work not only provides a detailed examination of alkylresorcinols in selected Polish rye and wheat cultivars and selected whole-grain cereal products, but also demonstrates that this type of analysis accompanied by the use of proper statistical algorithms offers an objective way to evaluate the quality of whole-grain rye and/or wheat and their derived products.  相似文献   
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Process parameter optimization for the supercritical CO(2) extraction of rye bran to obtain alkylresorcinols (AR) was studied by carrying out a two-level fractional design experiment. Four parameters, temperature, CO(2) flow rate, cosolvent percentage, and extraction time, presumed to influence the extraction process, were analyzed. A tentative fractionation of the crude extract was also carried out and is discussed. The best extracts were achieved when the CO(2) flow rate and extraction time or temperature and cosolvent addition were kept high. It was found that temperature increase was not statistically significant within the range of the study performed, and the extraction time was thus the most important factor. A preliminary fractionation process in two cyclone separators yielded two fractions, one rich in AR components with higher molecular weights and the other rich in AR components with low molecular weight.  相似文献   
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In a field experiment, winter rapeseed was grown in 5-year monoculture and in crop rotation (winter rapeseed, winter wheat, field peas, spring wheat and winter rapeseed). Two open-pollinated cultivars (Californium and Castille) and one hybrid cultivar (Nelson) were compared in systems with three levels of agricultural inputs, low input, medium input and high input, characterized by different rates of nitrogen and sulfur fertilization and pesticide use. The severity of sclerotinia rot (Sclerotinia sclerotiorum) and verticillium wilt (Verticillium spp.) on plants, dark spot (Alternaria spp.) and grey mold (Botrytis cinerea) on leaves and pods, as well as dry rot (Phoma lingam) on stems was evaluated during the growing season. The yield of winter rapeseed was calculated. Rapeseed grown after a 4-year break was characterized by less severe symptoms of dark spot on leaves and dry rot on stems, but more severe symptoms of grey mold on leaves and pods. The severity of dark spots on rapeseed pods (in crop rotation) was reduced with an increase in agricultural inputs. Cultivars Californium and Nelson were generally rarely infected by Verticillium spp., their leaves were less infected by Alternaria spp. and stems by Phoma spp. Nelson was the highest-yielding cultivar.  相似文献   
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The very rapid development of the road infrastructure in recent years has adversely affected the natural environment. The main effects of this have been the loss or deteriorating quality of habitats, the mortality of animals due to collisions with road vehicles, the withdrawal of birds as a result of disturbance and excessive noise in the neighbourhood of roads. In this study, we attempted to define the influence of a busy road on a breeding community of woodland birds. Individuals were counted using the point method at 54 observation points located at three various distances (60, 310, 560 m) from the road. At each point, we determined the habitat parameters and the intensity of noise. In total, 995 individuals of 39 species were recorded on the study plot. This study showed that the area was homogeneous with respect to habitat. The number of birds per point increased with distance from the road. Species diversity was lower near the road. The density of nine common species increased with distance from the road. Great Tit Parus major and Song Thrush Turdus philomelos preferred the neighbourhood of the road, whereas the numbers of the other species were the highest in the middle row of points. The number and species diversity of birds were correlated with the pattern of sound propagation across our study area. Our results showed that the species particularly sensitive to road traffic were those nesting near the ground and with low-frequency calls.  相似文献   
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The aim of this study was to investigate the evolution of the abundance of cytochrome oxidase c subunit IV (NCOIV) and beta subunit of ATP synthase (β-ATP) during the last third of gestation in bovine skeletal muscles. Semitendinosus, longissimus thoracis and rectus abdominis muscles were chosen for the immunoblotting of the respective protein levels. Muscle and blood samples from bovine fetuses of randomly selected breeds were collected at 180, 210, and 260 days post-conception (dpc). The muscle tissue expressions of NCOIV, β-ATP were compared to blood glucose and insulin. At 260 dpc, protein levels of NCOIV raised in skeletal muscles. Additionally, β-ATP in semitendinosus and longissimus thoracis were elevated and paralleled by higher concentrations of blood serum insulin. It corroborates our previous observations indicating that accelerated metabolic differentiation of bovine skeletal muscles is associated with elevated blood insulin and occurs during the last trimester of gestation. Our observations point to the connection between insulin-sensitivity and the molecular mechanisms of mitochondrial contribution to ontogenesis of skeletal muscles.  相似文献   
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The aim of this study was to determine the effect of different production systems (conventional, integrated and organic) on the content of micronutrients and trace elements in the tubers of very early, early and medium-early maturing potato cultivars. Five Polish potato cultivars were grown in three production systems under field conditions. In plant material selected microelements (chemical elements essential for living organisms) were analysed: boron (B), copper (Cu), iron (Fe), manganese (Mn) and zinc (Zn) as well as some trace elements (not regarded as essential element for living organisms): chromium (Cr), nickel, (Ni) and lead (Pb). The content of micronutrients and trace elements in potato tubers was modified by production system, genotype and weather conditions during the growing season. Organically grown potatoes had a higher content of B (8.6–8.9?mg kg?1) and Cu (2.8–3.1?mg?kg?1), and a lower content of Fe (47.0–47.1?mg?kg?1), Mn (6.0–6.4?mg?kg?1) and Zn (11.9–12.2?mg?kg?1), than potatoes grown in conventional and integrated systems. Potatoes grown in the conventional system had the highest Pb content. Organic cultivation can assure better alimentation of potato tubers with B and Cu, which are important microelements often deficient in the soils. On the contrary, when cultivating potato in conventional system, one should supply this element with fertilisers.  相似文献   
19.
The content and homologue composition of alkylresorcinols were investigated in rye seedlings (Secale cereale L.) treated with benzimidazole fungicides and grown for 5 days under various thermal and light conditions. The fresh and dry biomasses of green and etiolated plants were greatly increased by benomyl and carbendazim at 29 °C. At 22 and 15 °C benomyl had an inhibitory action on growth of rye, whereas the effects caused in the presence of carbendazim were slightly dependent on external stimuli. On the other hand, benomyl enhanced resorcinol biosynthesis in green seedlings grown at all temperatures, while carbendazim only at 29 °C. In plants kept in the darkness, both fungicides increased content of alkylresorcinols at 29 °C and decreased its at 22 and 15 °C. The qualitative pattern of resorcinolic homologues was also significantly modified in the presence of benomyl and carbendazim and depended on other physical stimuli.  相似文献   
20.
The occurrence of Eutric Cambisols in the study area has been usually attributed to specific characteristics of bedrock. Their basic properties include significant contrasts of pH and the content of carbonates within their profiles. Analysis of soil texture and the content and lithology of rock fragments indicate discontinuities in the parent material of the upper and lower sections of the investigated profiles. The observations have been confirmed by the analysis of XRD diffractograms of unseparated < 2 mm samples and of the > 2 μm fraction. The properties of the lowermost horizons are naturally related to the characteristics of bedrock, while cover-beds with a dominance of quartz and a lack of calcite should be recognized as parent material of the upper sections of the profiles. The XRD diffractograms of the clay fractions show a continuous, uniform process of soil development imposed on the originally heterogeneous profile.  相似文献   
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