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11.
Blood meal is an organic nitrogen (N) fertilizer containing about 10–13% organic N. The fertilizer is mainly composed of hemoglobin which is characterized by the presence of a prosthetic group containing iron (Fe). Knowledge about the influence of blood meal on soil organic matter and soil fertility is now limited. In this work, blood meal was incubated in the soil for one year and the evolution of the organic matter was followed at time intervals by use of isoelectric focusing (IEF) and humification parameters. The mineralization of the total N and the availability of some mineral nutrients (Fe in particular) were also followed. The results show that only a part (about 75%) of the organic carbon (C) and of the organic N mineralized and that the remaining C was transformed into humified compounds. The availability of the Fe increased during the incubation, probably due to the progressive degradation of the prosthetic group and the successive chelation of the Fe from the humic substances.  相似文献   
12.
The present paper briefly reviews the most relevant experimental data on the reducing effect of some medicinal herbs on voluntary alcohol intake in animal models of alcoholism. Pueraria lobata, Tabernanthe iboga, Panax ginseng, Salvia miltiorrhiza and Hypericum perforatum proved to be effective in decreasing alcohol consumption. Reduction of alcohol absorption from the gastrointestinal system appears to be a common feature among most of the above plants. These data suggest that medicinal plants may constitute novel and effective pharmacotherapies for alcoholism.  相似文献   
13.
There was only limited emphasis on anesthesia and pain management in veterinary colleges in Russia until the last ten years. There is now great interest in improvement by Russia practitioners. This effort is hampered by the lack of approved and available medications and limited instructions. At this time, the small animal practitioners have tranquilizers, alpha2 agonists local anesthetics and NSAID's for their use. Propofol is available through pharmacies and efforts are being made for veterinarians to use ketamine. Only a few practices have inhalant anesthetic units and halothane. During a recent lecture tour of Russia, general clinical principles and specific anesthetic and pain management protocols were taught. The audience, primarily young and progressive veterinarians, actively participated and showed great desire to practice quality anesthesia and pain management for their patients. Teaching young veterinarians how to manage their cases without the availability of opioids, ketamine advanced anesthetic equipment and monitors was indeed challenging. Protocols for perioperative management consisting of medetomidine with or without local anesthesia followed by carprofen for post-operative pain is an improvement. We sometimes spend so much time discussing which of many drug combinations we will use but seldom consider what we would do if we were practicing our specialty in parts of the world where we would have to modify dosages and combinations to achieve humane care with few drug choices.  相似文献   
14.
A 5-month-old female Rottweiler dog was diagnosed to have a neurodegenerative disease that has been recently report ed in Rottweilers from North America and Europe. The dog was presented with progressive signs of ataxia, tetraparesis and inspiratory stridor. The clinical investigation included analysis of CSF, radiography, myelography and electrophysiolog-ical testing. No evidence of vertebral malformation or inflammatory CNS disease was identified. Bilateral laryngeal paraly sis was identified in the lightly anaesthetised dog. Electromyography showed abnormal spontaneous activity from the intrin sic musculature of the larynx. At necropsy there were no gross abnormalities of the nervous system but there was atrophy of the dorsal cricoarytenoid muscles of the larynx. There were widespread histological abnormalities throughout the ner vous system including neuronal vacuolation, spongiform changes in the neuropil and axonal degeneration which was most prominent in the spinal cord. These clinical and pathological findings are consistent with the diagnosis of a new neurode-generative disease reported from North America and Europe. This diagnosis is of particular significance in Australia where transmissible spongiform encephalopathies have not been identified.  相似文献   
15.
16.
Photolysis of quinalphos, O,O-diethyl O-(quinoxalin-2-yl) phosphorothioate ( I ), in ethanolic solutions yields two products, O,O-diethyl O-(3-ethoxy-quinoxalin-2-yl) phosphorothioate ( II ) and O,O-diethyl O-(3-(1-hydroxyethyl)-quinoxalin-2-yl) phosphorothioate ( III ). Both products derive from the reaction of photo-excited quinalphos molecule with the solvent. The reactions follow first-order kinetics. A mechanism that accounts for the formation of the above mentioned products is proposed.  相似文献   
17.
Cyclodextrins are a group of cyclic oligosaccharides with a ring, basket-like structure. These compounds are able to include several kinds of molecules into their internal cavity, leading to important modifications of the properties of the guest compound. The interaction between β-cyclodextrin and the R and S enantiomers of dichlorprop, 2-phenoxypropionic acid and dioxabenzofos was investigated by means of molecular dynamics (MD). Several in vacuo trajectories were calculated for each system imposing a 1:1 stoichiometry. The results account for the formation of adducts which are stable at room temperature. The analysis of statistical data from the MD runs shows that dioxabenzofos exhibits the weakest interaction in the series studied and that the R and S enantiomers of dichlorprop and phenoxypropionic acid interact in a different fashion with the host molecule. © 1998 Society of Chemical Industry  相似文献   
18.
The sorption of N-[[(4,6-dimethoxypyrimidin-2-yl)amino]carbonyl]-1-methyl-4-(2-methyl-2H-tetrazole-5-yl)1H-pyrazole-5-sulfonamide (AZS) on an iron oxide, iron(III)-humate, and an Fe3+-saturated clay was studied using a batch equilibrium method. Generally, 20 mg of each colloid was equilibrated with 20 mL of AZS solution (1.5-12.7 microM). The sorption on iron-montmorillonite and iron oxide was rapid, and the equilibrium was attained within 1.5 and 5 h, respectively. In the case of Fe-saturated humic acid the equilibrium time was 20 h. After equilibration, the phases were centrifuged (19000g, 15 min) and the supernatant was sampled and analyzed by HPLC. The values of Freundlich constants indicate that iron oxide (Kads = 199.5) shows the highest sorptive capacity toward AZS, followed by iron(III)-clay (Kads = 146.6) and iron(III)-humate (Kads = 108.2). With elapsing time, AZS degradation was observed in all colloidal suspensions. Iron-humate (t(1/2) = 136 h) is most effective in promoting AZS degradation, followed by iron oxide (t(1/2) = 204 h) and iron-clay (t(1/2) = 385 h). The metabolites 2-amino-4,6-dimethoxypyrimidine and 1-methyl-4-(2-methyl-2H-tetrazole-5-yl)-1H-pyrazole-5-sulfonamide, arising from a hydrolytic cleavage of the sulfonylurea bridge, were the only byproducts observed. A Fourier transform infrared study suggests that the sorption of AZS on iron-clay involves the protonation of one of the two basic pyrimidine nitrogens induced by the acidic water surrounding the saturating Fe3+ ions. Instead, the formation of a six-membered chelated complex favors the sorption of AZS on iron oxide.  相似文献   
19.
Iron forms which characterize the clay fraction of four Cambisols from granite and the distribution of iron oxides in the soil profiles are studied by Mössbauer spectroscopy, X-ray diffractometry and selected chemical methods. The results obtained show that about 50 % of the Fet(6–10 % Fe) is not extracted by dithionite. The Feo/Fed ranges between 0.15 and 0.35. Oxalate dissolves goethite in different amounts, probably depending on the particle size and the Al-substitution level. The highest amount of hematite is found in the samples characterized by the lowest internal magnetic fields, suggesting that the soil distribution of hematite and goethite is related to environmental factors favouring or disfavouring Al-for-Fe substitution and crystallinity of the oxides.  相似文献   
20.
Azimsulfuron sorption--desorption on soil   总被引:11,自引:0,他引:11  
The sorption and desorption of the herbicide azimsulfuron, N-[[(4-dimethoxypyrimidin-2-yl)amino]carbonyl]1-methyl-4-(2-methyl-2H-tetrazole-5-yl)1H-pyrazole-5-sulfonamide, were studied using five soils. Sorption isotherms conformed to the Freundlich equation. It was found that pH is the main factor influencing the sorption and that the sorption on soils was negatively correlated with pH. The highest level of sorption was measured on soils with low pH and high organic carbon content. Moreover, inorganic soil colloids, for example, smectite clay minerals and iron oxides, contributed to the sorption of azimsulfuron. Desorption was hysteretic on soils with high organic and inorganic colloid contents.  相似文献   
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