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排序方式: 共有334条查询结果,搜索用时 15 毫秒
1.
Patrick Rehmann Andrea Gr?ne Bruno Gottstein Jürg V?llm Heinz Sager Martin Janovsky Luca N Bacciarini 《Journal of veterinary diagnostic investigation》2005,17(2):183-186
Five animals in a colony of cynomolgus monkeys (Macaca fascicularis) died or were euthanatized because of alveolar echinococcosis, during a period of 5 years. The remainder of the colony was screened for possible infection with Echinococcus multilocularis, using serology and ultrasonography. A total of 46 animals out of a group of 55 were examined. The presence of anti-Em2 antibodies analyzed with enzyme-linked immunosorbent assay was demonstrated in 3 monkeys. In 2 of these 3 monkeys, multilocular structures compatible with metacestodal cysts in the liver were identified, using ultrasonography. The presence of alveolar echinococcosis was subsequently confirmed at postmortem examination in 1 animal. The other animals are still alive. Two other monkeys were negative in the serological examination but had cystic structures in the liver, which were identified as bile duct cysts at postmortem examination in 1 animal. The other monkey is still alive. These findings suggest that serology for antibodies against the Em2 antigen may represent a useful method in identifying animals that might be infected with E. multilocularis and are therefore at risk of developing fatal alveolar echinococcosis. 相似文献
2.
High caudal epidural anaesthesia with local anaesthetics or alpha(2)-agonists in calves 总被引:1,自引:0,他引:1
Meyer H Starke A Kehler W Rehage J 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2007,54(7):384-389
The objective of this study was to examine the efficacy of a caudal epidural anaesthesia using lidocaine or xylazine in a high volume for analgesia of the flank, navel and hamstring tendon. Fourteen calves weighing 57.7 +/- 5.1 kg and 37.9 +/- 9.3 (mean +/- SEM) days old were randomly divided into two groups of seven calves each. Calves belonging to the lidocaine group were given a 2% lidocaine solution in the sacrococcygeal vertebral space epidurally at a volume of 0.4 ml/kg (8 mg/kg) body weight (BW). Animals of the xylazine group were administered an epidural anaesthesia with xylazine at a dose of 0.1 mg/kg BW, diluted with a 0.9% saline solution to a corresponding final volume of 0.4 ml/kg BW. Heart rate and respiratory rate were measured and the degree and duration of analgesia was determined by the response to a skin prick with a hypodermic needle over a period of 350 min after epidural injection. After epidural anaesthesia with lidocaine the mean heart rate increased during dorsal recumbency, whereas after xylazine both heart rate and respiratory rate decreased significantly (P < 0.05). The epidural injection of xylazine compared with lidocaine caused longer (P < 0.05) analgesia at the hamstring tendon (mean +/- SEM, 120.7 +/- 29.7 min versus 93.6 +/- 3.5 min) and at the flank (100.7 +/- 24.4 min versus 78.3 +/- 11.1 min). There were no differences in the intensity of analgesia between groups. After xylazine application analgesia at the navel was achieved for 95.0 +/- 14.1 min whereas after lidocaine injection sufficient analgesia at the navel was found in just two of seven calves for 55 and 95 min respectively. Based on above experiences, a second study was performed, in which a combination of xylazine and local anaesthetics was used and the injection volume was increased to prove the efficacy of caudal epidural anaesthesia in 15 calves (26.3 +/- 26.7 days; 57.1 +/- 19.5 kg) submitted to the clinic for regular umbilical surgery. In these cases the xylazine (0.1 mg/kg BW) was diluted with 2% lidocaine (n = 7) or 2% procaine (n = 8) to a corresponding final volume of 0.5-0.6 ml/kg BW. In all cases complete anaesthesia of the surgical area was achieved and no adverse effects were observed. Overall the high volume caudal epidural anaesthesia represents an effective, safe, cheap and easy to perform alternative for anaesthesia of the navel, flank and hamstring tendon in calves without major side effects. 相似文献
3.
Environmental effects on soil NO concentrations and root N uptake in beech and spruce forests
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Fang Dong Judy Simon Michael Rienks Jürgen Schäffer Klaus von Wilpert Heinz Rennenberg 《植物养料与土壤学杂志》2016,179(2):244-256
This study aimed to investigate the shifts in net nitrogen (N) uptake and N compounds of fine roots over the vegetation period (i.e., spring, summer, autumn) and correlate this with NO concentration in the soil. Soil NO concentration was measured using gas lysimeters for collection and a chemiluminescence analyzer for quantification. Net N uptake by the roots was determined using the 15N enrichment technique. N pools were quantified using spectrophotometric techniques. Soil NO concentrations at beech and spruce forest sites were highest in spring (June), and lowest in winter (December). Total N of the roots was similar during the seasons and between the two years under study despite considerable variation of different N compounds. Net N uptake generally increased with higher N supply. Correlation analysis revealed a positive relationship between soil NO concentration and net N uptake only for spruce trees. This relationship seemed to be modulated by environmental factors and tree species. 相似文献
4.
Stabilization mechanisms of organic matter in four temperate soils: Development and application of a conceptual model 总被引:2,自引:0,他引:2
Margit von Lützow Ingrid Kögel‐Knabner Bernard Ludwig Egbert Matzner Heinz Flessa Klemens Ekschmitt Georg Guggenberger Bernd Marschner Karsten Kalbitz 《植物养料与土壤学杂志》2008,171(1):111-124
Based on recent findings in the literature, we developed a process‐oriented conceptual model that integrates all three process groups of organic matter (OM) stabilization in soils namely (1) selective preservation of recalcitrant compounds, (2) spatial inaccessibility to decomposer organisms, and (3) interactions of OM with minerals and metal ions. The model concept relates the diverse stabilization mechanisms to active, intermediate, and passive pools. The formation of the passive pool is regarded as hierarchical structured co‐action of various processes that are active under specific pedogenetic conditions. To evaluate the model, we used data of pool sizes and turnover times of soil OM fractions from horizons of two acid forest and two agricultural soils. Selective preservation of recalcitrant compounds is relevant in the active pool and particularly in soil horizons with high C contents. Biogenic aggregation preserves OM in the intermediate pool and is limited to topsoil horizons. Spatial inaccessibility due to the occlusion of OM in clay microstructures and due to the formation of hydrophobic surfaces stabilizes OM in the passive pool. If present, charcoal contributes to the passive pool mainly in topsoil horizons. The importance of organo‐mineral interactions for OM stabilization in the passive pool is well‐known and increases with soil depth. Hydrophobicity is particularly relevant in acid soils and in soils with considerable inputs of charcoal. We conclude that the stabilization potentials of soils are site‐ and horizon‐specific. Furthermore, management affects key stabilization mechanisms. Tillage increases the importance of organo‐mineral interactions for OM stabilization, and in Ap horizons with high microbial activity and C turnover, organo‐mineral interactions can contribute to OM stabilization in the intermediate pool. The application of our model showed that we need a better understanding of processes causing spatial inaccessibility of OM to decomposers in the passive pool. 相似文献
5.
Tetracyclines are widely used in farm animals. This can cause drug residues in products of animal origin and, after excretion of these substances, in animal slurry and in soil fertilized with that slurry. In this paper, we present a method based on a microbiological assay coupled with HPLC for the detection of oxytetracycline, tetracycline, and chlortetracycline in eggs. After a simple liquid extraction of the samples and HPLC separation, fractions were collected on microtiter plates, and the tetracyclines were analyzed using the Staphylococcus aureus assay. This method was able to identify residues of tetracyclines in eggs at a level set by regulatory agencies (i.e., 200 microg/kg). In addition, it was shown that the described microbiological method can be used as a screening assay for the detection of tetracyclines and possible biologically active metabolites in animal slurry and soil samples. Employing the same extraction procedure, it was demonstrated that LC-MS-MS allowed the quantification of 20-400 microg/kg in eggs with recoveries ranging from 71 to 109% and RSDs of 3-15%. 相似文献
6.
Dr. H. J. Heinz 《Journal of pest science》1951,24(4):59-61
Ohne Zusammenfassung 相似文献
7.
Hans-Joachim Heinz 《Journal of pest science》1951,24(6):91-94
Zusammenfassung Es werden zwei Schwermetallgifte — Thalliumsulfat und Zinkphosphid — untersucht, hinsichtlich ihrer Giftwirkungen und K?derwirkungen
auf Hausratten. Es wird festgestellt, da? Thalliumsulfat in erheblich h?heren Dosen (7,6 mg/100 g Ratte) den Hausratten verabreicht
werden mu?, im Unterschied zu den Wanderratten, um eine mittlere t?dliche Dosis zu erreichen. Die K?derwirkung des Thalliumsulfats
ist gut und auch die erh?hte Dosierung wird von den Hausratten nicht abgelehnt. Die Dosierungen von Zinkphosphid für Hausratten
entsprechen denen, die bisher für Wanderratten üblich waren. Im Gegensatz zur Wanderratte zeigte die Hausratte keine Ablehnung
von Zinkphosphid bei wiederholten Gaben. Die durch subletale Fütterung von Zinkphosphid erreichte Gifttoleranz ist auf die
6fache t?dliche Dosis gesteigert worden. Selbst derart überdosierte K?der werden von den Hausratten nicht verschm?ht. 相似文献
8.
Mark K. Sears Cindy Bowhey Heinz Braun Gerald R. Stephenson 《Pest management science》1987,20(3):223-231
In laboratory experiments, residues of diazinon applied to turfgrass, Poa pratensis L., that could be dislodged by rubbing with cheese-cloth, declined from c. 10% of the total applied when the grass was vigorously rubbed immediately after application to 0.3% after 1 day. Sunlight did not influence the rate of decline in dislodgeable residues or residues remaining on or within the leaf blades. In field experiments where 4.5 kg ha?1 of diazinon was applied in liquid or granular form, about 20 times more diazinon was dislodged from the liquid formulation immediately after application than from the granular. By 1 day after application the percentage of the total applied diazinon that could be dislodged was equal for both formulations. Rainfall had a significant effect on the amount dislodged from grass blades, but mowing did not. Similar rates of decline in the dislodgeable fraction of diazinon, chlorpyrifos and isofenphos were observed in field experiments. Recovery of the dislodgeable fraction declined to 0.25% or less of the total amount of any of these insecticides by 1 day after application. However, residues in the thatch remained sufficiently high for control of insects for up to 7 days after application for diazinon and 14 days for chlorpyrifos and isofenphos. 相似文献
9.
H Waibl J Herrmann J Rehage P Lorenzi G Constantinescu 《DTW. Deutsche tier?rztliche Wochenschrift》2001,108(6):261-263
A relatively thick (diameter approximately 2 mm), ropelike (length ca. 20 mm) and elastic "Vinculum tendinis" connects--within the fetlock tendon sheath--the dorsal side of the deep digital flexor tendon with the dorsal part of the Manica flexoria (the communicating band of the Musculus interosseous medius to the superficial digital flexor tendon). The extensive fetlock tendon sheath can be involved in diseases such as aseptic and septic inflammations. Spreading of these inflammations makes in some of these cases the partial resection of the tendon of the deep digital flexor muscle and the cutting of these Vincula necessary. The results of this contribution, collected from 60 hindlimbs of adult bovines show variations in number, length, diameter and extent and the inner structure with blood vessels and nerves. 相似文献
10.
Alfons Pascual Alfred Rindlisbacher Heinz Schmidli Erich Stamm 《Pest management science》1995,44(4):369-379
The biological activity of a series of N-(pyrid-3-yl)thioureas and -carbodiimides, analogues of the insecticide/acaricide diafenthiuron, towards the carmine spider mite (Tetranychus cinnabarinus Boisd.) and the two-spotted spider mite (T. urticae Koch) was analysed using QSAR methodology. A canonical correlation analysis allowed for the establishment of a prediction model and the identification of outliers within that model. The chemodynamic behaviour of certain compounds in the two series, including these outliers, determined by using photochemical experiments in the laboratory as well as in the glasshouse, was shown to be responsible for anomalous results obtained in the biological tests. It was found from the above study that the biological activity towards both spider mite species is extremely sensitive to the kinetics of formation of the carbodiimides from the corresponding thioureas and to the photostability of the former. The results obtained with a thiourea which underwent no appreciable photochemical transformation into the corresponding carbodiimide supported the hypothesis that the thioureas are also in-vivo propesticides of the acaricidal carbodiimides. 相似文献