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1.
J Hahn 《DTW. Deutsche tier?rztliche Wochenschrift》1989,96(2):72-73
New biotechnical methods in reproduction have been introduced in animal breeding via embryo transfer. There are no serious objections against these methods as long as the variety of species is reassured and the animal protection law is considered. More substantial objections exist against genetic engineering methods which alter the genome of animals. Beside for legal protection there is a strong public demand for the adequete awareness and responsibility of scientists who are active in this field. Comprehensive information on such research projects can lead to a better understanding of the aims and methods and might, therefore, help to reduce inadequate apprehensions. 相似文献
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A neurologic syndrome in Golden Retrievers presenting as a sensory ataxic neuropathy 总被引:1,自引:0,他引:1
Jäderlund KH Orvind E Johnsson E Matiasek K Hahn CN Malm S Hedhammar A 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(6):1307-1315
BACKGROUND: A sensory ataxic neuropathy has been observed in Swedish Golden Retrievers recently. ANIMALS: Twenty-one affected Golden Retrievers. METHODS: Clinical and neurologic status, electrophysiologic, and pathologic status as well as pedigree analyses were evaluated. RESULTS: Clinical signs had an insidious onset between 2 and 8 months of age and a slowly progressive course. Affected dogs were ataxic and dysmetric. They had abnormal postural reactions and decreased spinal reflexes but no apparent muscle atrophy. Clinical pathology, radiography, and electrophysiology of motor systems were all within reference values. Sensory nerve conduction results of affected dogs were significantly different from those of a group of control dogs. Necropsy revealed a chronic progressive central and peripheral sensorimotor axonopathy; the proprioceptive pathways were most severely affected. CONCLUSIONS AND CLINICAL IMPORTANCE: This disease in these Golden Retrievers is distinct from other canine breed-related neurodegenerative diseases or hereditary neurodegenerative diseases described in humans. Pedigree analyses indicated a hereditary background, but the mode of inheritance could not be established. 相似文献
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Azin Rekowski Monika A. Wimmer Bernd Hitzmann Bernhard Hermannseder Heike Hahn Christian Zrb 《植物养料与土壤学杂志》2020,183(2):260-270
Background: Nitrogen losses is an economic problem for wheat production and a high risk to the environment. Therefore, improved N fertilizer management is a key to increasing the N efficiency and minimizing N losses. To increase N efficiency, enhanced fertilizers such as urea combined with urease inhibitor can be used. Aims: The aim of present study was to evaluate the effects of different N forms on grain storage protein subunits in winter wheat and to examine whether the observed changes correlate with parameters of baking quality. Methods: The investigation was performed over two consecutive years at two locations in Germany. Protein subunits were analyzed by SDS‐PAGE. Results: Protein concentrations were similarly increased after fertilization with ammonium nitrate and urea + urease inhibitor. Analysis of the individual storage protein fractions indicated that both fertilizers specifically enhanced ω‐gliadins and HMW glutenins, but the effect was more pronounced in the ammonium nitrate treatment. Application of urea + urease inhibitor had greater influence on the protein composition and resulted in higher specific baking volume as well as the best fresh keeping ability, in comparison with urea treatment. Conclusion: Considering that the urea + urease inhibitor treatment resulted in almost comparable improvements of NUE and baking quality, with the additional benefit of reduced N losses in combination with easy handling, urea + urease inhibitor can be recommended as a viable alternative to both urea alone and ammonium nitrate treatments. This opens up an opportunity for the reduction of N loss in wheat production when use of urea is preferred. 相似文献
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Pablo M. Vergara Luis O. Meneses Audrey A. Grez Madelaine S. Quiroz Gerardo E. Soto Christian G. Pérez-Hernández Paola A. Diaz Ingo J. Hahn Andrés Fierro 《Landscape Ecology》2017,32(2):279-293
Context
Interactions between landscape-scale processes and fine-grained habitat heterogeneity are usually invoked to explain species occupancy in fragmented landscapes. In variegated landscapes, however, organisms face continuous variation in micro-habitat features, which makes necessary to consider ecologically meaningful estimates of habitat quality at different spatial scales.Objectives
We evaluated the spatial scales at which forest cover and tree quality make the greatest contribution to the occupancy of the long-horned beetle Microplophorus magellanicus (Coleoptera: Cerambycidae) in a variegated forest landscape.Methods
We used averaged data of tree quality (as derived from remote sensing estimates of the decay stage of single trees) and spatially independent pheromone-baited traps to model the occurrence probability as a function of multiple cross-scale combinations between forest cover and tree quality (with scales ranging between 50 and 400 m).Results
Model support and performance increased monotonically with the increasing scale at which tree quality was measured. Forest cover was not significant, and did not exhibit scale-specific effects on the occurrence probability of M. magellanicus. The interactive effect between tree quality and forest cover was stronger than the independent (additive) effects of tree quality and particularly forest cover. Significant interactions included tree quality measured at spatial scales ≥200 m, but cross-scale interactions occurred only in four of the seven best-supported models.Conclusions
M. magellanicus respond to the high-quality trees available in the landscape rather than to the amount of forest per se. Conservation of viable metapopulations of M. magellanicus should consider the quality of trees at spatial scales >200 m.7.
8.
L. Daroda K. Hahn D. Pashkoulov E. Benvenuto 《Physiological and Molecular Plant Pathology》2001,59(6):317
The activation of Fusarium moniliforme endopolygalacturonase (endoPG) was studied during infection of maize plants. EndoPG is a plant cell wall degrading enzyme that cleaves the pectin component causing cell death. The authors generated several hybridoma cell lines producing endoPG specific monoclonal antibodies. One monoclonal antibody was selected and successfully used in Western blotting analysis to detect F. moniliforme endoPG secretion in vitro and in planta. Two F. moniliforme strains (FC-l0 and 62264) were used for the studies. Both strains revealed the expression of a single endoPG in vitro as in planta. EndoPG from strain FC-10 presented four isoforms whereas only two isoforms were revealed in the endoPG from strain 62264. Differences were also found in the sequences of the two endoPG genes indicating the presence of endoPG variability among F. moniliforme strains. 相似文献
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A survey of Diplomates from the American College of Veterinary Ophthalmologists, which trains residents, confirms that subjective criteria are most commonly used in selecting new residents. The ophthalmologist(s) who oversee(s) the training was/were primarily responsible for resident selection. In general, Diplomates seemed to be searching for a resident who was intelligent, could communicate well, was hard working, and had good interpersonal skills. The most important part of an application was the letters of recommendation, with the most important consideration being how well the person doing the selecting knew the author of a letter. The current process of resident selection does result in a majority of residents' completing their programs and ultimately becoming Diplomates of the American College of Veterinary Ophthalmologists. 相似文献
10.
Canine infectious respiratory disease (CIRD) is a multi-factorial infection that affects many kennelled dogs despite the wide use of vaccination. Current vaccines aim to protect against viral agents and a single bacterial agent, Bordetella bronchiseptica. We sought to examine the role of streptococcal species in CIRD. The isolation and identification of streptococci in the lower respiratory tract of clinically healthy dogs and those with CIRD were used to correlate the presence of specific streptococcal species with respiratory disease. In this study we report that the presence of S. equi subsp. zooepidemicus is associated with increasing severity of disease in a population of kennelled dogs with endemic CIRD. 相似文献