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1.
Lions (Panthera leo) are an endangered species threatened by illegal hunting, habitat loss, and infectious diseases. Little is known about the tick-borne pathogens that infect lions and could contribute to population declines. The objective of this study was to characterize Rickettsia spp., Anaplasma phagocytophilum, and Coxiella burnetii infections in 10 lions from the Fasano Safari Park in Italy by serology, polymerase chain reaction, and sequence analysis. Although animals did not show clinical signs of tick-borne diseases, evidence of infection with C. burnetii, spotted fever group Rickettsia sp., and A. phagocytophilum were found in 50%, 20%, and 10% of the lions, respectively. One of the lions tested positive for all three pathogens. This study is the first report of molecular evidence of infection with C. burnetii, Rickettsia sp., and A. phagocytophilum in lions and provides evidence that these felids become infected and serve as hosts for tick-transmitted bacteria.  相似文献   
2.
A sensitive and specific method is described for the simultaneous determination of oxytetracycline, tetracycline (TC), and chlortetracycline residues in edible swine tissues, by combining liquid chromatography with spectrofluorometric and mass spectrometry detection. The procedure involved a preliminary extraction with EDTA-McIlvaine buffer acidified at pH 4.0, followed by solid-phase extraction cleanup using a polymeric sorbent. The liquid chromatography analysis was performed with spectrofluorometric detection after postcolumn derivatization with magnesium ions. The limits of quantification were 50 microg/kg for muscle and 100 microg/kg for kidney tissues. The recovery values were greater than 77.8% for muscle and 65.1% for kidney. The method has been successfully used for the quantification of tetracyclines in swine tissues samples. The selective liquid chromatography mass spectrometric analysis for confirmation of oxytetracycline in one positive swine muscle sample was made by atmospheric pressure chemical ionization (APCI). The APCI mass spectra of the TCs gave the protonated molecular ion and two typical fragment ions, required for their confirmation in single ion monitoring scan mode in animal tissues.  相似文献   
3.
Effect of organic fertilizer on plankton primary productivity in fish ponds   总被引:2,自引:0,他引:2  
The effect of cattle organic fertilizer on plankton primary production and related variables was tested in six Bulgarian fish ponds situated close to the town of Plovdiv in Bulgaria. At the beginning of the experiment (16th of May 2004, about 10 days after filling with water) a suppression of plankton metabolism was observed and after that the ponds treated with manure demonstrated significantly higher productivity than the controls, especially during the transition to the autumn season when the water column was more regularly mixed. The other measured variables (Secchi disk readings, plankton chlorophyll-a and respiration, assimilation number per unit chlorophyll-a) did not show significant differences between the treated and control ponds.  相似文献   
4.
Water column processes in undisturbed mangrove creeks and in creeks receiving effluent from shrimp farms in North Queensland, Australia, were studied. Small scale discharges into tidal creeks did not elevate dissolved nutrient concentrations compared with non‐impacted creeks, but did elevate concentrations of particulate nutrients, chlorophyll and suspended solids proximal to the site of the effluent discharge. Rates of primary and bacterial production downstream from the discharge exceeded rates in the shrimp ponds because of the synergistic effects of turbulent mixing and eutrophication. In the lower reaches of the mangrove creeks and immediately offshore, standing stocks of particulate material and rates of primary and bacterial production were within the range of values found in non‐discharge areas. Our results suggest that water column production by phytoplankton and bacteria strips nutrients from shrimp farm effluent and repackages them in more bioavailable forms.  相似文献   
5.
Mass balance estimates of carbon and nitrogen flux through two extensive shrimp ponds in the Mekong delta, Vietnam, were constructed to identify major sources and sinks of organic matter potentially available for shrimp production. Nutrient transformations in the sediments were measured to further assess rates of decomposition and burial and quality of organic matter. Tidal exchange was the major pathway for inputs and outputs of carbon and nitrogen in both ponds, with net primary production, nitrogen fixation and precipitation being minor inputs. No fertilizers or artificial feeds were added to either pond. The nutrient budgets identified burial and respiration as the next most important outputs after tidal exchange losses of particulate and dissolved carbon and nitrogen. There was no measurable denitrification in either pond, and volatilization was negligible. Mineralization efficiency of carbon in the water column was high (> 100%) in pond 23 reflecting rapid respiration rates; efficiency was lower (36%) in pond 12 waters. Mineralization efficiency of sediment nutrients averaged 34% for C and 41% for N in the pond with a higher annual shrimp yield (pond 12); lower mineralization efficiencies (11% for C, 10% for N) were calculated for the lower yield pond (pond 23). High burial efficiencies for both C (66–89%) and N (59–90%) in the sediments of both ponds suggest that little organic matter was shunted into biological production. Conversion efficiency for shrimp averaged 16% for C and 24% for N from pond 12, and 6% for C and 18% for N from pond 23. The high quantity but low quality of organic matter entering the ponds coupled with other factors, such as poor water quality, limits shrimp productivity. On average, nutrient outputs were greater than inputs in both ponds. This imbalance partly explains why shrimp yields are declining in these ponds.  相似文献   
6.
Forty-three secondary metabolites were isolated and characterized from cv. Annurca apple fruit, an apple variety cultivated in the south of Italy. This apple cultivar undergoes a typical reddening treatment after collection. All of the compounds were characterized on the basis of their spectroscopic data. The compounds were tested for their radical-scavenging and antioxidant activities by measuring their capacity to scavenge DPPH* (2,2'-diphenyl-1-picrylhydrazyl radical), H2O2, and NO (nitric oxide) and to inhibit the formation of methyl linoleate conjugated diene hydroperoxides or TBARS (thiobarbituric acid reactive species).  相似文献   
7.
We compared the effects of medium light roast (MLR) and medium roast (MR) paper-filtered coffee on antioxidant capacity and lipid peroxidation in healthy volunteers. In a randomized crossover study, 20 volunteers consumed 482?±?61?ml/day of MLR or MR for four weeks. Plasma total antioxidant status (TAS), oxygen radical absorbance capacity (ORAC), oxidized LDL and 8-epi-prostaglandin F2α, erythrocyte superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) activity were measured at baseline and after the interventions. MLR had higher chlorogenic acids-(CGA; 334?mg/150?mL) and less caffeine (231?mg/150?ml) than MR had (210 and 244?mg/150?ml, respectively). MLR also had fewer Maillard reaction products (MRP) than MR had. Compared with baseline, subjects had an increase of 21 and 26?% in TAS, 13 and 13?% in CAT, 52 and 75?% in SOD, and 62 and 49?% in GPx after MLR and MR consumption (P?相似文献   
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9.
Tetraconazole, a new, recently introduced antifungal triazole, has been assayed in parallel with a number of standard analogues on various sensitive strains of Ustilago maydis. The values of EC50 and EC90 tetraconazole concentrations, determined on strain ATCC 14826 in agar, were 0.5 × 10−6 and 3.5 × 10−5 , respectively, in reasonable agreement with those needed to inhibit by 50% and 90%, respectively, the ergosterol biosynthesis in broth cultures. Squalene and 12 sterols have been extracted from the latter, characterized and quantified. Accumulation of 14α-methylsterols and reduction of ergosterol and other late precursors are consistent with the inhibition of 14α-demethylase caused by the title compound.  相似文献   
10.
Ochratoxin A (OTA) is an important mycotoxin with potential to reach the human food chain through carry-over of contaminated, mostly cereal-based, feed into animal-derived products. Certain population groups, such as infants and children, are intensive and relatively restricted consumers of some animal-derived products, particularly milk and other dairy products, which may become contaminated with OTA. This review examines the literature on the occurrence of OTA in animal-derived products and discusses the public health and food safety implications of consumption of these products. The risk of OTA contamination of meat, milk, blood and derived products is discussed.  相似文献   
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