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It has now been established that circovirus infection is common in farmed geese, but little is known about the clinicopathological significance of such infections. Ten clinically diseased geese suspected of being infected by circovirus were studied by in situ hybridization using a goose circovirus DNA probe. Circovirus DNA was demonstrated in the bursa of Fabricius (BF), spleen, thymus, bone marrow, liver, kidney, lung and heart, indicating that infection can be multisystemic. In some birds, virus DNA was present in very large quantities, most notably in the BF, liver and small intestine. With the exception of BF and thymus, there were no histological findings that would have suggested the presence of such quantities of circovirus DNA. In view of the very large quantities of virus DNA labelling present in some tissues, and by analogy to porcine circovirus type 2 infection and psittacine beak and feather virus infections, which are known to cause severe disease, and which have similar virus distribution to that found in our geese, it seems probable that the circovirus was important in the disease manifestations shown by the infected geese. 相似文献
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Antigenic analysis of Neisseria gonorrhoeae by crossed immunoelectrophoresis. 总被引:12,自引:10,他引:12 下载免费PDF全文
Crossed immunoelectrophoresis was used to study two complex antigenic preparations from Neisseria gonorrhoeae, one of cytoplasmic origin and the other derived by Triton X-100 extraction of isolated washed gonococcal envelopes, with the aim of developing suitable reference antigen-antibody systems that could be subsequently used to investigate the immune response to gonococcal infection and to monitor envelope preparations for cytoplasmic contamination. A number of parameters were investigated to optimized and standardize antigen preparation, e.g., harvesting and washing of gonococci, methods of bacterial disruption, and washing of envelopes. The effects of Triton X-100 concentration, initial total envelope protein concentration, and the composition, pH, and concentration of buffer on cell envelope extractability were studied to obviate the need to concentrate material before use in crossed immunoelectrophoresis. The electroendoosmotic properties of agarose were a major determining factor in resolving envelope antigens. From 25 to 30 immunoprecipitates were revealed in the envelope antigen-antibody system; 75 to 80 were revealed in the cytoplasmic sytem. Envelope immunoprecipitates with reduced nicotinamide adenine dinucleotide and lactate dehydrogenase activities were identified. Crossed immunoelectrophoresis with intermediate gels revealed the presence of antibodies in a preimmune rabbit antiserum pool to a distinctive fact-moving component in both the envelope and cytoplasmic antigen preparations. The intermediate gel technique also demonstrated that extensive washing of envelope preparations with buffer did not remove cytoplasmic ontamination completely. The method provides a much more sensitive means of monitoring the purity of envelope fractions than the use of single enzy,e markers as indexes of such contamination. The use of rabbit antisera raised to formolized gonococci in intermediate gels indicated that both reference antigen-antibody systems were of potential use in screening immune responses to N. gonorrhoeae. 相似文献
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Guus MJ Bökkerink Maja Joosten Erik Leijte Maud YA Lindeboom Ivo de Blaauw Sanne MBI Botden 《Journal of pediatric surgery》2021,56(3):465-470
BackgroundMinimal invasive surgery (MIS) is increasingly used for the correction of congenital diaphragmatic hernia (CDH) and esophageal atresia (EA). It is important to master these complex procedures, preferably preclinically, to avoid complications. The aim of this study was to validate recently developed models to train these MIS procedures preclinically.MethodsTwo low cost, reproducible models (one for CDH and one for EA) were validated during several pediatric surgical conferences and training sessions (January 2017–December 2018), used in either the LaparoscopyBoxx or EoSim simulator. Participants used one or both models and completed a questionnaire regarding their opinion on realism (face validity) and didactic value (content validity), rated on a five-point-Likert scale.ResultsOf all 60 participants enrolled, 44 evaluated the EA model. All items were evaluated as significantly better than neutral, with means ranging from 3.7 to 4.1 (p < 0.001). The CDH model was evaluated by 48 participants. All items scored significantly better than neutral (means 3.5–3.9, p < 0.001), with exception of the haptics of the simulated diaphragm (mean 3.3, p = 0.054). Both models were considered a potent training tool (means 3.9).ConclusionThese readily available and low budget models are considered a valid and potent training tool by both experts and target group participants.Type of studyProspective study.Level of evidenceLevel II. 相似文献
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Olasveengen Theresa M. Semeraro Federico Ristagno Giuseppe Castren Maaret Handley Anthony Kuzovlev Artem Monsieurs Koenraad G. Raffay Violetta Smyth Michael Soar Jasmeet Svavarsdóttir Hildigunnur Perkins Gavin D. 《Notfall & Rettungsmedizin》2021,24(4):386-405
Notfall + Rettungsmedizin - Der Europäische Rat für Wiederbelebung hat diese Leitlinie – Basismaßnahmen zur Wiederbelebung – auf Grundlage des... 相似文献
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