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1.
Summary During studies on the helminth fauna of wolves inhabiting natural ecosystems of Poland, 86 scats were examined. All the samples were collected in the autumn of 2005. Spirocerca lupi was detected with decantation and flotation techniques. The prevalence was 2.32 %. This is the first record of the parasite from Poland and the third case of its occurrence in the wolf (Canis lupus L.) within its distribution range.  相似文献   
2.
Purified secretory acetylcholinesterase (sAChE) from Trichostrongylus colubriformis was used as a candidate vaccine against mixed T. colubriformis, Haemonchus contortus and C. oncophora challenge infections of sheep. Cross species protection was achieved with an average reduction in worm burden of all species of 31%, rising to 58% in individual cases. There was no consistent reduction in faecal egg counts and increases in anti-T. colubriformis sAChE IgG antibody levels following vaccination were modest. We suggest that improved antigen delivery systems will result in increased host protection.  相似文献   
3.
Immunofluorescence on live Dictyocaulus viviparus parasites revealed a significant antibody response by vaccinated and patently infected bovine hosts to the sheath of infective larvae (L3), a structure which is generally thought to be shed from the parasite surface prior to invasion of host tissue. In contrast, surface-exposed antigens of the adult, egg and pulmonary L1 stages were recognized only by serum antibody from calves exposed to a patent lungworm infection. Radioiodination of sheathed L3 identified a restricted set of components while a more complex pattern of labelled material was observed with adult parasites. Many more components of adult worms were labelled by the Bolton-Hunter than by the lodogen reagent, probably reflecting the more penetrative labelling propensities of the former. Stage-specificity of surface-associated antigens of adult parasites was demonstrated by their immunoprecipitation by antibody from patently-infected, but not from vaccinated, calves. There was no in vitro release of the major iodinatable surface-associated antigens of adult parasites nor any binding of antibody raised against adult excretory-secretory (ES) products to the surface of living adult worms, suggesting that surface components do not contribute to adult ES products in this species. Antibody responses to the surface of adults. L1 and eggs were specific to patently-infected animals and may provide a useful indicator of exposure to patent infection.  相似文献   
4.
Three gonad-infecting species of Philometra Costa, 1845 were, for the first time, recorded from perciform fishes from estuarine and marine waters in South Carolina and Georgia, USA: Philometra charlestonensis sp. nov. from the scamp Mycteroperca phenax (Jordan et Swain) (Serranidae), P. saltatrix Ramachandran, 1973 from the bluefish Pomatomus saltatrix (Linnaeus) (Pomatomidae), and Philometra sp. from the Atlantic croaker Micropogonias undulatus (Linnaeus) (Sciaenidae). The new species is characterized mainly by males (body length 2.65–3.14 mm) with equally long, needle-like spicules (length 132–141 μm) and the gubernaculum (81–93 μm) bearing dorsal transverse lamella-like structures on its distal portion, the body length of gravid females (168–247 mm), the presence of a well-developed anterior bulbous inflation on the female oesophagus, and by the length of the first-stage larvae (544–597 μm). A key to gonad-infecting species of Philometra parasitizing marine and brackish-water fishes is provided.  相似文献   
5.
Parasitic nematodes infect more than 1 billion people in the global south. The development of effective antihelminthic vaccines is a crucial tool for their future elimination. Protective immune responses to nematodes depend on Gata3+ Th2 cells, which can also be induced by nematode-released products. Whether these nematode products induce antigen-specific long-lived memory T cells and thereby confer protection against a challenge infection is not known yet. Hence, we set out to characterize the formation of memory Th2 cells induced by immunization with Heligmosomoides polygyrus excretory-secretory (HES) products, infection-induced versus immunization-induced recall responses to a challenge infection, and whether HES-induced memory T cells show protective properties following adoptive transfer. Our results show that 8 weeks postimmunization, HES induces long-lived functional memory Th2 cells at the site of immunization in the peritoneal cavity. Following a H. polygyrus challenge infection, HES-immunized mice display MHC-II-dependent antigen-specific Th2 cytokine responses in the gut-draining lymph nodes, comparable to those induced by a prior natural infection. Moreover, adoptive transfer of sorted memory CD4+ T cells from HES-immunized donors reduces female worm fecundity following a challenge H. polygyrus infection in recipient mice, highlighting a protective role for immunization-induced memory T cells.  相似文献   
6.
We report a case of human Dirofilaria repens infection in a woman in Slovenia who had concomitant pleural and subcutaneous manifestations of the infection. This case report illustrates the clinical course of a severe symptomatic parasitic infection that had multisystemic manifestations.  相似文献   
7.
应用昆虫病原线虫防治枸杞负泥虫的研究   总被引:4,自引:1,他引:4  
程惠珍  陈君  杨军 《中草药》1998,29(2):119-121
枸杞负泥虫LemadecempuntataScopoli是药用植物枸杞的重要害虫。我们从它的体背上经常覆盖有茶褐色虫屎的特性考虑,应用昆虫病原线虫进行了防治试验。在室内筛选中发现这种害虫对芫菁夜蛾线虫Steinernemafeltiae及小卷蛾线虫S.carpocapsae十分敏感,感染死亡率达90%以上。在田间防治中,用1500~1600条/mL线虫悬浮液喷在枸杞上,杀虫效果可达70%以上。试验证明,昆虫病原线虫对枸杞负泥虫的防治是具有应用前景的。  相似文献   
8.
9.
In ace-2;ace-1 double mutants of the nematode C. elegans, where the major acetylcholinesterase (AChE) classes A and B have been eliminated by mutation, the animals are viable and residual AChE activity remains. This residual activity differs markedly from AChE classes A and B; its Km for acetylcholine is 1000-5000-fold lower, its resistance to eserine is 3000-260,000-fold higher, it is markedly more thermo-labile, and it can be separated from classes A and B by ion exchange chromatography. It has been designated class C AChE. Class C AChE of indistinguishable properties is also present in wild type C. elegans, at levels approximating those seen in ace-2;ace-1 double mutants, suggesting that it is controlled by a third, as yet unidentified, gene. Amongst other sources examined, class C-like AChE has been detected in another nematode species, Stepkanurus dentatus, but not in Drosophila melanogaster, Torpedo californica, or Rattus rattus.  相似文献   
10.
目的 了解四川省国家级监测点2006-2010年居民土源性线虫病感染时段变化及其影响因素,了解居民的菜园、厕所周边、厨房和庭院4类环境中土壤蛔虫卵污染情况,掌握土源性线虫病的流行规律,为制定防治对策提供科学依据.方法 采用改良加藤厚涂片法和透明胶纸肛拭法,对监测点常住居民土源性线虫感染情况进行调查;2006-2010年共对50户农家的菜园、厕所周边、庭院、厨房采集土壤标本,每个场所各检测土壤样本50份,用饱和硝酸钠漂浮法检查土壤蛔虫卵污染情况.结果2006-2010年共检查5616人,其中男性2725人,女性2891人.2006-2010年土源性线虫感染率分别为32.06%、14.4%、10.16%、3.21%和5.62%.男、女性蛔虫、钩虫、鞭虫感染率分别为1.32%、11.16%、0.37%和1.56%、11.41%、0.42%.2006-2010年土源性线虫、蛔虫、钩虫和鞭虫的感染率呈下降趋势;2006-2010年菜园、厕所周边、庭院、厨房土壤中活受精蛔虫卵的检出率分别为6.0%、4.0%、2.0%和4.0%,各场所未受精蛔虫卵、受精蛔虫卵、活受精蛔虫卵的分布差异均无统计学意义,但受精蛔虫卵的检出和活受精蛔虫卵检出随年份变化呈下降趋势.结论 四川省国家级监测点2006-2010年人群土源性线虫感染率呈下降趋势,与当地村民服药驱虫密切相关;土壤中人蛔虫卵的检出情况随着年份变化也呈下降趋势.  相似文献   
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