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排序方式: 共有716条查询结果,搜索用时 31 毫秒
1.
作者在广东省梅县市发现四个吸虫新种:1.鼠丽色吸虫,新种Reesella ratta sp. nov., 2.后囊蛙蠕吸虫,新种Batrachotrema optstosacca sp. nov., 3.梅县后平睾吸虫,新种Opisthioparorchis meixianensis sp. nov., 4.大卵后平睾吸虫,新种Opisthioparorchis megaloonos sp. nov.,它们分别归隶于蹲茎科Cathaemasiidae及蛙蠕科Bstrachotrematidae。模式标本保存于中山医科大学寄生虫学研究所。 相似文献
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The critical relationship between free radicals and degrees of ischemia: evidence for tissue intolerance of marginal perfusion 总被引:8,自引:0,他引:8
M F Angel S S Ramasastry W M Swartz K Narayanan D B Kuhns R E Basford J W Futrell 《Plastic and reconstructive surgery》1988,81(2):233-239
Skin-flap ischemia has been associated with the presence of free radicals. In this study, two enzyme systems involved in free-radical metabolism were used to compare a distal skin flap to a skin graft. Forty-two rats were divided into several test groups. A 10 X 3 cm dorsal rat flap was used, and tissue biopsies for xanthine oxidase and malonyldialdehyde (MDA) were obtained 2.5, 5.5, and 8.5 cm from the base of the flap at the hours given. In group I (control), the flap was outlined but not elevated, and biopsies were obtained. In group II, the flap was elevated, and biopsies were obtained at 6 hours. In group III, the flap was elevated, the distal 4 X 3 cm was amputated and replaced as a full-thickness skin graft, and biopsies were obtained at 6 hours. In group IV, the flap was elevated, and biopsies were obtained at 12 hours. In group V, the flap was treated as in group III, and biopsies were obtained at 12 hours. In group VI, the flap was elevated, and biopsies were obtained at 24 hours. In group VII, the flap was treated as in group III, and biopsies were obtained at 24 hours. Results: Xanthine oxidase was significantly higher in all distal biopsies compared to proximal biopsies. Xanthine oxidase also increased with time. Malonyldialdehyde increased over time as well as with distance from the flap base. Distal flap biopsies at 24 hours had greatly increased levels of malonyldialdehyde compared to skin grafts (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
3.
Leishmanial phosphatase blocks neutrophil O-2 production 总被引:9,自引:0,他引:9
A T Remaley D B Kuhns R E Basford R H Glew S S Kaplan 《The Journal of biological chemistry》1984,259(18):11173-11175
Leishmania donovani, the causative agent in kala-azar or visceral leishmaniasis, infects cells of the macrophage system. We show that a purified preparation of the tartrate-resistant acid phosphatase, isolated from the external surface of L. donovani promastigotes, inhibits superoxide anion production by human neutrophils. Preincubation of neutrophils for 15-30 min at 37 degrees C with 240 units (1 unit equals 1 nmol of 4-methylumbelliferyl phosphate cleaved per h) of the acid phosphatase decreases both the rate and extent of superoxide generation by 90% upon stimulation with the chemoattractant peptide fMet-Leu-Phe. The ability of the phosphatase to suppress superoxide anion production is abolished by heat inactivation of the enzyme or by incorporation of an acid phosphatase inhibitor in the preincubation medium, indicating that the effect is dependent on the catalytic activity of the enzyme. These results suggest a possible pathophysiologic role for the acid phosphatase of L. donovani promastigotes. 相似文献
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对我国52种微茎类吸虫的18项成虫形态学特征进行主成分分析,结果表明:卵巢位置、子宫延伸位置等7项性状对第一主成分贡献较大,提示描述器官位置的指标是重要的分类依据。52个虫种在前三个主成分上的排序图显示应将其划分成4个亚科。 相似文献
7.
本文就萤叶甲亚科中柱萤叶甲属鞘翅具黑色刻点的种类进行研究,共记述4种,我国已记录3种,其中1种为新种。 相似文献
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维生素C·Cu·菲咯啉系统对DNA的定位损伤 总被引:4,自引:0,他引:4
维生素C·Cu·菲咯啉系统对DNA的定位损伤柯德森,王爱国,罗广华(中国科学院华南植物研究所,广州510650)关键词活性氧;DNA;定位损伤活性氧对DNA的损伤已经被很多工作所证实”””,这种伤害是由0B”直接作用于DNA所引起的”’“。但是OH’... 相似文献
10.
本文报道在湛江市附近海域海鸟体内获得的两种吸虫,经鉴定为新种,命名为巨口类茎吸虫,新种Microphalloides macrostonrs sp.nov.,珊瑚多黄吸虫,新种Multivitellus coralius sp.nov. 相似文献