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排序方式: 共有110条查询结果,搜索用时 15 毫秒
71.
72.
André Tadeu Gotardo Rafael Lanzelloti Fonseca Fabiano Barreto Caroline Andrade Tomaszewski Lucas Suchecki Barnet Tamara Castilho Silvana Lima Górniak 《Journal of veterinary pharmacology and therapeutics》2020,43(5):477-484
Ivermectin (IVM) is one of the most widely used antiparasitic drugs worldwide and has become the drug of choice for anthelmintic and tick treatment in beef cattle production. It is known that pharmacokinetic parameters are fundamental to the rational use of a drug and food safety and these parameters are influenced by different factors. The aim of this study was to evaluate the pharmacokinetic profile of IVM in Bos indicus, Bos taurus, and crossbreed cattle (B. indicus × B. taurus) kept under same field conditions and the possible impacts of sex and IVM formulation (1% and 3.15%). It was observed that IVM concentration was significantly affected by breed. The plasma concentrations of IVM, AUC, Cmax, and t1/2β were significantly higher in B. indicus compared to B. taurus. Crossbreed animals showed an intermediate profile between European and Indian cattle. No alteration in pharmacokinetics parameters was detected when comparing different gender. Concerning the pharmacokinetic data of IVM formulation, it was verified that Tmax, AUC, and t1/2β were higher in 3.15% IVM animals than those from 1% IVM formulation. The results clearly indicated that the IVM plasma concentrations in B. indicus were higher than that in B. taurus. 相似文献
73.
Baronti Silvia Galassi Elena Ugolini Francesca Miglietta Franco Genesio Lorenzo Vaccari Francesco P. Cacciatori Pierino Gazza Laura 《Genetic Resources and Crop Evolution》2022,69(2):619-633
Genetic Resources and Crop Evolution - Perennial crops are emerging as an effective strategy for adapting to climate change, but also for mitigating net greenhouse gas emissions from agriculture.... 相似文献
74.
PCBs and organochlorine pesticides were determined in water, sediment and zooplankton of two Himalayan lakes, located at different altitudes and connected to each other in such a way that Superior Lake acts as a sedimentation basin for Inferior Lake. Surficial sediments of both lakes show PCB contamination comparable to lakes of industrialised areas. Biota appear to be the main machanism responsible for micropollutant burial in the sediments of Inferior Lake, whereas inorganic particles are more relevant in Superior Lake. Physical and chemical properties of individual chemicals, particularly Henry's law constant and Kow values, seem to regulate distribution in different environmental compartments. 相似文献
75.
Mônica Matoso Campanha Ricardo Henrique Silva Santos Gilberto Bernardo de Freitas Hermínia Emília Prieto Martinez Silvana Lages Ribeiro Garcia Fernando Luiz Finger 《Agroforestry Systems》2004,63(1):75-82
This research compared coffee plants (Coffea arabica L.) grown in an agroforestry and monoculture systems. Data were collected during two years, on vegetative growth, reproductive
development, nutritional status and yield of coffee, besides monitoring air temperature and the tree growth. All trees in
agroforestry system increased in growth, resulting in a reduction in the magnitude of the diurnal temperature variation and
also maximum temperature. Coffee plants in agroforestry system had less branch growth and leaf production, more persistent
and larger leaves, and presented earlier flowering, with a smaller number of productive nodes and flower buds, leading to
smaller berry yield than plants in monoculture system. In both systems, the coffee plants showed adequate leaf nutrient levels,
except for P and K. The yield of 2443 kg ha-1 of coffee from the monoculture was greater than 515 kg ha-1 of coffee from the agroforestry system. 相似文献
76.
Cerdeira M Martini S Hartel RW Herrera ML 《Journal of agricultural and food chemistry》2003,51(22):6550-6557
The effects of addition of the sucrose esters (SE) P-1670, P-170, and S-170 to a high-melting fraction of milk fat (HMF) and its blends with sunflower oil (SFO) on nucleation and growth were studied by laser polarized light turbidimetry and polarized light microscopy (PLM). The three SE delayed nucleation of HMF at the temperatures selected. P-1670 did not modify average crystal size after 3 h at crystallization temperature (T(c)) or crystal size distribution and modified crystallization kinetics only slightly. P-170 and S-170, however, markedly diminished crystal size and narrowed crystal size distribution. Activation free energies of nucleation at equivalent supercooling, calculated using the Fisher-Turnbull equation, significantly increased with addition of SE. According to these results, among the mechanisms described in the literature for fats or emulsions, the cocrystallization hypothesis is the one that better described the effects of sucrose esters on crystallization behavior in these systems. 相似文献
77.
Contamination by DDT of industrial origin was detected in 1996 in Lake Maggiore (Northern Italy) causing concern for wildlife and human health. Starting from 1998 a monitoring programme involving different research laboratories was undertaken to establish the pollution level of the lake. In assessing the ecological risk to Lake Maggiore wildlife during this period, the present study integrates information provided by the Commission for the Protection of Italian and Swiss Waters with further analysis and ecotoxicological tests carried out on some autochthonous target species for this insecticide. Sediments collected at the end of 1997 in the most contaminated bay (total DDT 860.2 ng g?1 dry weight) caused a decrease in fertility and growth of benthic oligochaetes and chironomids, while the 48 h IC50 for Daphnia galeata (0.76 μg L?1, c.i. 0.43–1.34) was much higher than the DDT concentration in the lake water. The risk of acute effects on zooplankton should therefore be excluded, while transfer through the trophic web and bioconcentration in fish and fish-eating birds are the most adverse consequences of DDT contamination in Lake Maggiore. 相似文献
78.
Castelo-Branco PA Rubinger MM Guilardi S Leite VM dos Santos AR de C Alves L Lariucci C Vencato I Piló-Veloso D Zambolim L 《Pest management science》2009,65(1):34-40
BACKGROUND: Avenaciolide, a natural product isolated from Aspergillus avenaceus H. Smith, possesses several interesting biological properties, such as antifungal and antibacterial activities and inhibition of glutamate transport in mitochondria. In a study aiming to discover new compounds with antifungal activity, a bis‐γ‐lactone analogous to avenaciolide was prepared and characterized by elemental analysis, mass spectrometry, and infrared and NMR spectroscopy. RESULTS: The absolute structures of this compound and of the synthetic precursor (also a bis‐γ‐lactone) were determined by X‐ray diffraction analysis. The bis‐γ‐lactones synthesized crystallize in the orthorhombic space group P212121, and the crystal packings are supported by C? H···O hydrogen bonds. The compound showed antifungal activity against Colletotrichum gloeosporioides (Penz.) Penz. & Sacc., while the synthetic precursor was inactive under the in vitro test conditions employed. CONCLUSION: The results indicate that it is not only the bis‐γ‐lactone skeleton that is important to antifungal activity. The latter also depends on the presence of the exocyclic double bond possibly due to a Michael addition type reaction with the fungal enzymes. Copyright © 2008 Society of Chemical Industry 相似文献
79.
Cucher MA Carnevale S Prepelitchi L Labbé JH Wisnivesky-Colli C 《Veterinary parasitology》2006,137(1-2):74-82
Fasciolosis, caused by the trematode Fasciola hepatica, is a zoonosis of economic importance in livestock that is emerging as a chronic disease in humans. The intermediate hosts are lymnaeid snails, in which diagnosis of infection is traditionally based on cercarial shedding, tissue sectioning and crushing. We developed a PCR assay for the sensitive and specific detection of F. hepatica in field-collected Lymnaea sp. snails. A primer pair was designed to amplify a 405 bp fragment of the cytochrome c oxidase subunit 1 gene of F. hepatica. The PCR assay showed a limit of detection of 10 pg of genomic F. hepatica DNA. No cross-reactions were observed with samples from other related trematode species or from the snail hosts Lymnaea columella and Lymnaea viatrix. DNA sequencing of the amplicon showed 100% homology with F. hepatica, and 75-89% homology with other trematodes on regions that did not include the entire set of primers. Two samples from Argentina were analysed. For snails in sample 1 (n = 240), identified as L. columella, the infection rate was 17.5 and 51.3% by direct examination and PCR, respectively. For snails in sample 2 (n = 34), identified as L. viatrix, the infection rate was 2.9 and 61.8% by direct examination and PCR, respectively. Differences in infection rates between these diagnosis methods were significant for both samples. Our PCR technique showed to be effective for detecting specific F. hepatica infections of low intensity in the intermediate host, and hence it could be used to study the epidemiological situation in a given area, as well as to assess host suitability for the parasite. 相似文献
80.
Ecotoxicological assessment of the effects of glyphosate and chlorpyrifos in an Argentine soya field 总被引:2,自引:0,他引:2
Norma Casabé Lucas Piola Julio Fuchs María Luisa Oneto Laura Pamparato Silvana Basack Rosana Giménez Rubén Massaro Juan C. Papa Eva Kesten 《Journal of Soils and Sediments》2007,7(4):232-239