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FDA-approved, postoperative use of leeches can lead to bacterial infections. In this study, we used culture-dependent and culture-independent approaches to characterize the digestive-tract microbiota of Hirudo orientalis. Surprisingly, two Aeromonas species, A. veronii and A. jandaei, were cultured. Uncultured Rikenella-like bacteria were most similar to isolates from Hirudo verbana. 相似文献
75.
Control of nematode parasites with reduced reliance on the use of anthelmintics was studied in 16 ewes with suckling twin
lambs on contaminated pasture in Denmark. Ewes and lambs were treated with albendazole at turn-out 3 May. Ewes were removed
from the groups on 26 July, and lambs were slaughtered on 11 October. The animals were allocated to 4 groups of 8 lambs and
their 4 ewes. Group TS was treated with albendazole at weeks 3, 6 and 8 after turnout and set-stocked; group TM was similarly
treated but moved to clean pasture in conjunction with the last drenching; group US was untreated and set-stocked, and group
UM was left untreated but moved to clean pasture week 8 after turn-out. Supplementary feed was offered in June and August
due to scarcity of pasture. Strategic treatments of ewes and lambs weeks 3, 6 and 8 after turn-out, with or without a move
to clean pasture, were highly effective in controlling nematode infections for most of the season. This was reflected in better
weight gains and carcass characteristics in the treated compared to untreated lambs, resulting in an average increase in the
value of the product by 36%. The effect of moving without treatment (UM) on faecal egg counts was limited but peak pasture
infectivity was reduced to less than 10% compared to the set-stocked group and weight gains of lambs were significantly better
despite poor feed availability in late season. The study showed that under set-stocked conditions repeated anthelmintic treatments
of both ewes and lambs in early season may ensure sufficient nematode control whereas moving animals to clean pasture without
dosing was less efficient. The latter may, however, still be a viable option in organic and other production systems where
routine use of anthelmintics is banned, particularly if weaning and moving are combined or a second move is performed. 相似文献
76.
MR Scrochi CN Zanuzzi N Fuentealba F Nishida ME Bravi ME Pacheco 《Biotechnic & histochemistry》2017,92(8):560-568
Many viruses alter different stages of apoptosis of infected cells as a strategy for successful infection. Few studies have addressed mechanisms of equine herpesvirus 1 (EHV-1) strain-induced cell death. We investigated the effect of an abortigenic strain (AR8 strain) on heterologous Madin–Darby bovine kidney cells and homologous equine dermis (ED) cells cell lines. We compared morphologic and biochemical features of early and late apoptosis at different postinfection times. We investigated translocation of phosphatidylserine to the cell surface, nuclear fragmentation and changes in the cytoskeleton using flow cytometry and annexin V/propidium iodide staining, DNA laddering, terminal deoxynucleotidyl transferase UTP nick-end labeling assay and immunofluorescence staining of cytokeratin 18 cleavage. AR8 EVH-1 strain interfered with apoptosis in both cell lines, particularly during the middle stage of the replication cycle; this was more evident in ED cells. Although this antiapoptotic effect has been reported for other alpha herpesviruses, our findings may help elucidate how EHV-1 improves its infectivity during its cycle. 相似文献
77.
在中国应用垂直波束雷达监测褐飞虱和其他水稻害虫迁飞的可行性 总被引:1,自引:0,他引:1
J.R.Riley A.D.Smith D.R.Reynolds 《Entomologia Sinica》2003,10(1):1-19
近年来,可用于昆虫迁飞研究且可自动运行的垂直波束雷达(vertical-looking radar,VLR)的发展使得对迁飞性害虫的周年长期自动监测成为可能。本文提供了我们对能否将这种雷达应用于中国的褐飞虱和其他水稻害虫的监测与预测体系以改善其综合治理的可行性研究结果。以往的研究已经表明,这些害虫一般在300—2000m高度迁飞;而我们根据褐飞虱的雷达和射有效截面的计算结果表明,目前使用的3.2cm波长的VLR对褐飞虱个体目标的最大可检测高度仅约240m;虽然建造一部8.8mm波长的VLR即可覆盖褐飞虱迁飞高度的绝大部分,但其造价和维护费用均过于昂贵。为此,一个更可行的解决方案是,以3.2cm波长的VLR作为包括大多数水稻害虫在内的个体较大的迁飞性害虫的监测工具。 相似文献
78.
Cristián Ituarte Estefanía Bagnato Mark Siddall Florencia Cremonte 《Systematic parasitology》2014,88(1):63-73
A new species of Haplosporidium Caullery & Mesnil, 1899 parasitising the pulmonate gastropod Siphonaria lessonii Blainville in Patagonia, Argentina, is described based on morphological (scanning and transmission electron microscopy) and sequence (small subunit ribosomal RNA gene) data. Different stages of sporulation were observed as infections disseminated in the digestive gland. Haplosporidium patagon n. sp. is characterised by oval or slightly subquadrate spores with an operculum that is ornamented with numerous short digitiform projections of regular height, perpendicular to and covering its outer surface. The operculum diameter is slightly larger than the apical diameter of the spore. Neither the immature nor mature spores showed any kind of projections of the exosporoplasm or of the spore wall. Regarding phylogenetic affinities, the new species was recovered as sister to an undescribed species of Haplosporidium Caullery & Mesnil, 1899 from the polychaete family Syllidae Grube from Japanese waters. The morphological characters (ornamentation of the operculum, spore wall structure, shape and size of spores, and the lack of spore wall projections) corroborate it as an as yet undescribed species of Haplosporidium and the first for the phylum in marine gastropods of South America. Siphonaria lessonii is the only known host to date. 相似文献
79.
ANOTHER MONOPHYLY INDEX: REVISITING THE JACKKNIFE 总被引:1,自引:0,他引:1
Mark E. Siddall 《Cladistics : the international journal of the Willi Hennig Society》1995,11(1):33-56
Abstract — Randomization routines have quickly gained wide usage in phylogenetic systematies. Introduced a decade ago, the jackknife has rarely been applied in cladistic methodology. This data resampling technique was re-investigated here as a means to discover the effect that taxon removal may have on the stability of the results obtained from parsimony analyses. This study shows that the removal of even a single taxon in an analysis can cause a solution of relatively few multiple equally parsimonious trees in an inclusive matrix to result in hundreds of equally parsimonious trees with the single removal of a taxon. On the other hand, removal of other taxa can stabilize the results to fewer trees. An index of clade stability, the Jackknife Monophyly Index (JMI) is developed which, like the bootstrap, applies a value to each clade according to its frequency of occurrence in jackknife pseudoreplicates. Unlike the bootstrap and earlier application of the jackknife, alternative suboptimal hypotheses are not forwarded by this method. Only those clades in the most parsimonious tree(s) are given JMI values. The behaviour of this index is investigated both in relation to a hypothetical and a real data set, as well as how it performs in comparison to the bootstrap. The JMI is found to not be influenced by uninformative characters or relative synapomorphy number, unlike the bootstrap. 相似文献
80.
Nigel T. Maidment Brenda Siddall Veronica D. Rudolph Christopher J. Evans 《Journal of neurochemistry》1991,56(6):1980-1984
Microdialysis combined with a solid-phase radioimmunoassay was used to monitor changes in extracellular opioid peptide levels in the rat globus pallidus/ventral pallidum as a result of terminal brain ischemia. Ischemia was induced by anesthetic overdose or by severance of blood vessels supplying the brain. In control animals the recovered immunoreactivity increased an average of 13-fold in the 30-min sample following anesthetic overdose. Perfusion of a calcium-free, 10 mM EGTA-containing medium through the dialysis probe significantly attenuated the amplitude of this response, with the average increase being only threefold. Shorter sampling intervals (5 min) indicated that release of opioid peptide material into the extracellular environment occurs within the first 5 min of ischemia resulting from severance of the blood supply to the brain. HPLC analysis identified the majority of the postmortem-induced immunoreactive material as Met- and Leu-enkephalin. 相似文献