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Dr. B. Lange 《Journal of pest science》1950,23(2):23-24
Ohne Zusammenfassung 相似文献
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A. De Meyer S. Vandenabeele C. Ververs A. Martens K. Roels V. De Lange M. Hoogewijs C. De Schauwer J. Govaere 《Equine Veterinary Education》2017,29(1):7-9
An 11‐year‐old gelding presented with a large mass located in the dermis of his preputium that surrounded the penis completely. This mass was first noted years ago but did not increase in size. Histological examination diagnosed a fibroma. No treatment was initiated since no signs of discomfort were noticed and the gelding was performing at a high level in competitive showjumping. Next to skin tumours, tumours of the penis and preputium are most common. Most frequently, squamous cell carcinomas and sarcomas are diagnosed. Although fibromas can develop anywhere in connective tissue, a preputial location of a fibroma in a gelding is rare. Differential diagnosis and possible treatment options are discussed. 相似文献
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Knueppel A Lange S Altmann S Sekora A Knuebel G Vogel H Lindner I Freund M Junghanss C 《Veterinary immunology and immunopathology》2012,145(1-2):233-240
Denileukin Diftitox (ONTAK®, DAB389 IL-2) is a recombinant DNA-derived fusion protein depleting cells that express high-affinity IL-2 receptor. Important cell targets are CD4+CD25+Foxp3+ regulatory T cells (Treg). Elimination of immunosuppressive Treg by Denileukin Diftitox may provide a way to modulate immune tolerance following stem cell transplantation. Here, we combined Treg depletion with a vaccination approach to induce donor-specific immune reactions. To investigate this approach we chose the mixed chimerism canine stem cell transplantation model which represents a high state of tolerance between two hematopoietic systems. The aim was therefore to induce a graft versus hematopoiesis effect thereby converting mixed to full donor chimerism. Dog leukocyte antigen identical siblings that had developed a stable mixed chimerism after non-myeloablative stem cell transplantation received a single dose of Denileukin Diftitox (18 μg/kg, i.v.) followed by several cell-lysate vaccinations. Host peripheral blood mononuclear cell lysates combined with CpG-ODN, and Montanide® ISA 51 were locally applied. In vitro studies demonstrated that canine Treg are a target of Denileukin Diftitox. The suppression of T-cell proliferation by Treg was abolished by addition of Denileukin Diftitox (10 nM). An increase of proliferation of median 300% (range: 200%–425%) was observed. No change in donor chimerism was observed after administration of Denileukin Diftitox and vaccination. This study highlights that application of Denileukin Diftitox resulted in a depletion of Treg followed by an increase of immune response in vitro. This effect could not be confirmed in vivo even if the immune system was stimulated by vaccinations. 相似文献
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ARB HIGGS RT NORRIS FC BALDOCK NJ CAMPBELL S. KOH RB RICHARDS 《Australian veterinary journal》1996,74(3):215-220
Objective: To investigate control options for contagious ecthyma (scabby mouth) in Australian sheep exported live to the Middle East.
Design: Prevalence, vaccination and modelling studies.
Procedure: One hundred and forty weaner sheep (less than 1 year old) on each of 106 farms in Western Australia (WA) and 18 farm groups of adult wethers received at a WA commercial feedlot were examined for lesions of scabby mouth. Sheep on a total of 26 farms in 3 States were divided into treatment and control groups for the vaccination study. A simple deterministic compartmental model was developed to establish which parameters had the greater effect on disease prevalence.
Results: The proportion of farms with evidence of scabby mouth in weaner sheep was 23.6% and, on those farms with the disease, the overall prevalence was 6.1%. At the feedlot, 4 out of 18 farm groups had 5 or more sheep with lesions on arrival. The overall prevalence in the 4 diseased groups was 5.2%. Sheep vaccinated on farm before trucking to the feed-lot had a lower prevalence of scabby mouth at the end of simulated shipping than controls. The main determinant of scabby mouth prevalence was the proportion of sheep immune to the disease.
Conclusion: A program of vaccination for scabby mouth will reduce the prevalence of disease during live export. However, using current technology it is not possible to deliver shipments of sheep to the Middle East that are guaranteed completely free of scabby mouth. 相似文献
Design: Prevalence, vaccination and modelling studies.
Procedure: One hundred and forty weaner sheep (less than 1 year old) on each of 106 farms in Western Australia (WA) and 18 farm groups of adult wethers received at a WA commercial feedlot were examined for lesions of scabby mouth. Sheep on a total of 26 farms in 3 States were divided into treatment and control groups for the vaccination study. A simple deterministic compartmental model was developed to establish which parameters had the greater effect on disease prevalence.
Results: The proportion of farms with evidence of scabby mouth in weaner sheep was 23.6% and, on those farms with the disease, the overall prevalence was 6.1%. At the feedlot, 4 out of 18 farm groups had 5 or more sheep with lesions on arrival. The overall prevalence in the 4 diseased groups was 5.2%. Sheep vaccinated on farm before trucking to the feed-lot had a lower prevalence of scabby mouth at the end of simulated shipping than controls. The main determinant of scabby mouth prevalence was the proportion of sheep immune to the disease.
Conclusion: A program of vaccination for scabby mouth will reduce the prevalence of disease during live export. However, using current technology it is not possible to deliver shipments of sheep to the Middle East that are guaranteed completely free of scabby mouth. 相似文献
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随着社会经济的快速发展,我国农业进入转型升级的关键时期,面临着更多的机遇和挑战,唯有加快推动农业发展方式的转变,提升农业质量、效益和竞争力,才能夯实农业发展的根基,确保农民收入的稳定增加。通过对我国传统农业向现代化新型农业转型过程中存在问题的深入分析,探索适合我国国情的现代新型农业模式和农业科技服务体系的构建,并在此基础上预测现代新型农业的发展趋势和推广策略,坚持走优质、高效和绿色的农业生态道路,推动农业的可持续发展。 相似文献
10.
Beet cyst nematodes (BCN, Heterodera schachtii), Cercospora beticola, and rhizomania, caused by the beet necrotic yellow vein
virus (BNYVV) and vectored by the soil-borne fungus Polymyxa betae, are the most serious diseases of sugar beet ( Beta vulgaris
subsp. vulgaris). The wild Beta species of section Procumbentes are known to be completely resistant to H. schachtii, C. beticola
and P. betae. Alien monosomic additions (2n=19), plants of cultivated beet (2n=18) carrying different individual chromosomes
of B. procumbens (2n=18) or B. patellaris (2n=36), were tested in greenhouse experiments for resistance to these pathogens.
Gene(s) conferring full resistance to the beet cyst nematode in B. patellaris are located on chromosome 1.1, and the other
tested chromosomes of B. patellaris are not involved in the expression of resistance. Artificial inoculation under greenhouse
conditions, with in vitro produced inoculum of C. beticola and spot-percentage rating of the disease intensity, showed that
the high level of resistance that was observed in the wild species B. procumbens and B. patellaris was not found in any of
the monosomic additions tested. It was suggested that genes on various chromosomes of the wild species are needed to express
full resistance, and that the chromosomes of group 7 of B. patellaris and chromosome 7 of B. procumbens have the largest effect.
The greenhouse tests for resistance to P. betae in B. patellaris derived monosomic additions showed that the addition families
of group 4.1 have a strong partial resistance, while the addition families of group 8.1 appeared to be completely resistant
to the pathogen. Resistance to P. betae in the two wild species as well as in the two resistant addition types did not exclude
infection with BNYVV, but resulted in a considerable reduction of the virus concentration. It was concluded that resistance
to the vector would complement virus resistance, and may provide a more effective and durable control of rhizomania.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献