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The presence of illicit drugs and their metabolites in surface waters has to be considered a new type of hazard, still unknown, for the aquatic ecosystem, due to the potent pharmacological activities of all the illicit drugs. Our research was therefore aimed at evaluating the impact of illicit drugs on the aquatic fauna, till now still undervalued. To this aim, we verified the ability of the European eel (Anguilla anguilla), a well-known biomonitor of environmental contamination, to bioaccumulate cocaine, one of the most abundant illicit drugs found in surface waters. Silver eels were exposed to a nominal cocaine concentration of 20?ng/l for 1?month; at the same time, control, carrier, and post-exposure recovery groups were made. Brains, gills, liver, kidney, muscle, gonads, spleen, digestive tract, and sections of dorsal skin were assayed by high-pressure liquid chromatography. Cocaine was found in the tissues of the treated eels and, at low concentrations, in almost all tissues of post-exposure recovery eels. These results indicate that cocaine is able to accumulate into the eel tissues; its presence suggests potential risks for eels since cocaine could affect their physiology and contribute to their decline, and for humans consuming contaminated fish.  相似文献   
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The inheritance of ocular colobomata in Charolais cattle   总被引:2,自引:0,他引:2  
The examination of approximately 800 pure bred and cross bred Charolais cattle indicated that ocular colobomata is inherited via an autosomal dominant gene in this breed. Penetrance was found to be complete in the male and partial (52 per cent) in the female. Inheritance in the crossbred animals was different to that in the pure bred.  相似文献   
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This study examined the effects of organic enrichment on water column, sediments and macrofauna caused by a fish farm in the Mediterranean Sea. Samples were collected on four sampling campaigns over a one‐year cycle. Significant differences were found in the water column in dissolved oxygen, dissolved inorganic nitrogen, phosphate and total phosphorus concentrations between the fish farm and the control. The increase in the dissolved inorganic nitrogen and phosphate concentrations at the fish farm modified the stoichiometric ratios between nutrients, with silicate acting as limiting nutrient at the fish farm 11% more than at the control. Nevertheless, chlorophyll a concentration in the water column was higher at the control station, probably due to the fouling of the underwater fish farm structures. Significant differences were found in sediment concentrations of organic matter, total phosphorus and redox potential between the fish farm and the control. The Canonical Correlation Analysis indicated that organic matter, total phosphorus, redox potential and% of gravels accounted for 68.9% of the total variance in the species data. Changes were observed in macrofauna, with a decrease in number of species and up to a nine‐fold increase in abundance with respect to the control.  相似文献   
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Plant Foods for Human Nutrition - This study aimed at evaluating and comparing the chemical profile obtained by HPLC-ESI-MSn analysis, the inhibitory activity of enzymes linked to obesity...  相似文献   
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Utilization of long‐chain fatty acids (LCFA) as diet composition markers, combined or not with alkanes, was evaluated in a study performed with sheep, goats and cattle fed on two different diets composed of herbaceous species and heather. Proportions of plant species were estimated from LCFA concentrations in plant species and faeces, using least‐square procedures, and were compared with those obtained using alkanes or LCFA + alkane. The impact of grouping plant species with similar LCFA + alkane profiles and the application of different levels of feeding selectivity within the dietary group on the accuracy of estimates were also assessed. Results showed that LCFA faecal recoveries were incomplete and tended to increase with carbon‐chain length in a curvilinear fashion in both diets and all animal species. Furthermore, differences between ruminant species and diets in the LCFA faecal recovery were observed. Combination of alkanes and LCFA provided the most accurate estimates of diet composition, while estimates based on LCFA alone were better than those using alkanes alone. Accuracy of these estimates differed among animal species but was not influenced by diet composition. Grouping plant species with similar LCFA + alkane profiles reduced the accuracy of estimates with a clear underestimation of the dietary group.  相似文献   
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