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981.
Murine macrophages were treated with various doses of cyclosporin A (CsA) to enhance the killing of Leishmania major parasites. CsA reduced the rate of infected cells from 75% in non-treated controls to less than 15% with 1 micro g CsA/ml in a dose-dependent manner. The leishmanicidal effect was also observed when CsA was added 48 h after the infection of macrophages. In contrast, FK506, another structural non-related immunosuppressive drug with antiparasitic activities, showed no effect on the ability of macrophages to kill intracellular Leishmania parasites. Since nitric oxide has been identified as a key molecule for the leishmanicidal function of macrophages, we analyzed the role of this molecule. There was no influence on the leishmanicidal effect of CsA when L- N-(1-iminoethyl)lysine, a potent and selective inhibitor of mouse inducible nitric oxide synthase, was added. Furthermore, the presence of the macrophage-inhibiting cytokines interleukin (IL)-10 and IL-13 simultaneously or prior to CsA did not inhibit leishmania killing, while both cytokines completely prevented parasite killing by macrophages activated with gamma interferon and tumor necrosis factor (TNF). CsA was fully active on macrophages from TNF-receptor p55 knockout mice arguing against autocrine activation by TNF. We therefore conclude that the antileishmanial effect of CsA is independent of effector mechanisms employed by macrophage-activating cytokines. 相似文献
982.
Jacek Dabert Agnieszka Badek Maciej Skoracki 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2007,52(3):250-267
Two new genera and three new species of feather mites (Astigmata, Pterolichoidea, Analgoidea) are described from two closely
related species of cockatoos, Cacatua galerita (type host) and C. sulphurea (Psittaciformes, Cacatuidae): Astrolabelichus caudatus gen. nov., sp. nov. (Pterolichidae), Psittophagus lacunosus sp. nov. (Pterolichidae), and Cacatualges microdiscus gen. nov., sp. nov. (Xolalgidae). The presence of the same set of mite species on these two species of parrots points to
a very close affinity of Cacatua sulphurea and C. galerita and gives additional support for the recent hypothesis of the conspecificity of these birds. 相似文献
983.
Anna Okulewicz Jerzy Okulewicz Joanna Hildebrand Grzegorz Zaleśny 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2007,52(3):292-294
Three male specimens of the eyeworm, Oxyspirura chabaudi, were found during the post mortem examination of one individual of Turdus merula L. (Passeriformes). This is the first record of Turdus merula as a host for O. chabaudi. 相似文献
984.
Background
Rosai-Dorfman Disease is an uncommon benign systemic histio-proliferative disease. This is the first time the disease, although more common in people of African descent, is described in association with Sickle cell disease. 相似文献985.
986.
通过人工合成了人类免疫缺陷性病毒(Humanimmunodeficiencyvirus,HIV)糖蛋白肽GP120对人和无脊椎动物(Mytilusedulis)免疫细胞的抑制作用的研究。人单核细胞和Mytilusedulis免疫细胞分别与GP120保温后,均抑制细胞的吞噬细菌(Psudomonasstretzi)作用。应用计算机显微图像术(Computer-assistedmicroscopy)直 相似文献
987.
988.
The activation of red blood cell transketolase in groups of patients especially at risk from thiamin deficiency 总被引:1,自引:0,他引:1
M D Jeyasingham O E Pratt A Burns G K Shaw A D Thomson A Marsh 《Psychological medicine》1987,17(2):311-318
Erythrocyte transketolase activation by thiamin diphosphate has been studied in elderly patients with moderate or severe chronic dementia, acute alcoholic admissions and chronic alcoholics with evidence of brain damage, mostly of the Wernicke-Korsakoff type. Significantly more patients in each group than controls showed abnormal activation of transketolase, not only by 0.3 mM thiamin diphosphate (TDP) but also in further activation by increase to 3 mM. This indicated the presence in a proportion of the alcoholic and the demented patients of an abnormal enzyme variant, similar to that previously found in vitro. The modified transketolase activation test may warn not only of marginal thiamin deficiency but also independently, of susceptibility to brain damage in patients at risk. 相似文献
989.
Background
There is currently an unprecedented expressed need and demand for estimates of maternal mortality in developing countries. This has been stimulated in part by the creation of a Millennium Development Goal that will be judged partly on the basis of reductions in maternal mortality by 2015. 相似文献990.