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141.
HB Jatsa ET Ngo Sock LA Tchuem Tchuente P Kamtchouing 《African journal of traditional, complementary, and alternative medicines》2009,6(3):216-221
Clerodendrum umbellatum Poir (Verbenaceae) is traditionally used in Cameroon for the treatment of many diseases including intestinal helminthiasis. This study was undertaken to assess the in vivo antischistosomal activity of its leaves aqueous extract on a Schistosoma mansoni mice model and to determine the most effective dose of this extract. Mice showing a patent infection of S. mansoni were daily treated with C. umbellatum leaves aqueous extract at the doses of 40, 80 or 160 mg/kg body weight for 14 days. Seven days after administration of the extract, schistosomicidal activity was evaluated on the liver and spleen weights, faecal eggs releasing, liver egg count and worm burden. Treatment using C. umbellatum leaves aqueous extract resulted in an important reduction in faecal egg output by 75.49 % and 85.14 % for 80 mg/kg and 160 mg/kg of the extract respectively. These reduction rates did not differ significantly from the 100 % obtained in the group of infected mice treated with 100 mg/kg of praziquantel. C. umbellatum leaves aqueous extract was lethal to S. mansoni worm. A 100 % reduction rate was recorded in the group of infected mice treated with 160 mg/kg of the extract, as well as in praziquantel-treated mice. An amelioration of the hepatosplenomegaly was noticed in both the extract-treated mice and the praziquantel-treated mice. From these results, we can conclude that C. umbellatum leaves aqueous extract demonstrated schistosomicidal properties in S. mansoni model at doses of at least 80 mg/kg body weight. 相似文献
142.
目的 探索C5a是否与LPS、毒源性大肠杆菌O157产生的外毒素-V毒素(verotoxin)具有相似的可以导致血管内皮细胞(VEC)凋亡的作用.方法 流式细胞仪榆测细胞凋亡发生率,首先探讨rhC5a刺激的质量浓度,分别为0.2μg/mL、0.5μg/mL、1μg/mL和1.5μg/mL刺激12 h检测VEC凋亡发生率;在rhC5a质量浓度均为1 μg/mL条件下,时间分别为2 h、6 h、12 h、18 h和24 h,检测VEC凋亡发生率.Western blot方法检测凋亡相关蛋白.结果 在rhCSa质量浓度为0.2μg/mL、0.5 μg/mL、1 μmL和1.5μg/mL刺激12 h诱导的凋亡发生率分别为4.58%、7.87%、17.94%和19.03%.在确定rhC5a质量浓度1μg/mL的条件下,VEC发生凋亡呈时间依赖关系,在2 h,6 h、12 h、18 h和24 h的时相,细胞凋亡发生率分别为4.58%、12.78%、18.12%、19.08%和19.96%.rhC5a刺激VEC细胞,calpain-2蛋白表达呈时间依赖性,而calpain-1蛋白的表达为浓度依赖性.结论 C5a可以导致VEC细胞发生凋亡,calpain参与了这类细胞的凋亡进程. 相似文献
143.
Background and purpose:
In the mammalian brain, histaminergic neurotransmission is mediated by the postsynaptic histamine H1 and H2 receptors and the presynaptic H3 autoreceptor, which also acts as a heteroreceptor. The H1 receptor has been implicated in spatial learning and memory formation. However, pharmacological and lesion studies have revealed conflicting results. To examine the involvement of histamine H1 receptor in spatial reference and working memory formation, H1 receptor knockout mice (KO) were tested in the eight-arm radial maze. Previously, we found that the H1 receptor-KO mice showed reduced emotionality when confronted with spatial novelty. As it is known that emotions can have an impact on spatial learning and memory performance, we also evaluated H1 receptor-KO mice in terms of emotional behaviour in the light–dark box.Experimental approach:
Mice lacking the H1 receptor and wild-type mice (WT) were tested for spatial reference and working memory in an eight-arm radial maze with three arms baited and one trial per day. Emotional behaviour was measured using the light–dark test.Key results:
The H1 receptor-KO mice showed impaired spatial reference and working memory in the radial maze task. No significant differences between H1 receptor-KO and WT mice were observed in the light–dark test.Conclusions and implications:
The spatial memory deficits of the H1 receptor-KO mice might be due to the reported changes in cholinergic neurochemical parameters in the frontal cortex and the CA1 subregion of the hippocampus, to impaired synaptic plasticity in the hippocampus, and/or to a dysfunctional brain reward/reinforcement system. 相似文献144.
目的观察米非司酮终止早孕后,绒毛和蜕膜内纤维粘连蛋白(FN)的表达情况。方法宫内早孕要求终止妊娠且孕龄〈49d的妇女,分为药物完全流产组(n=15)、药物不全流产组(n=15)和对照组(手术流产组,n=15)。两药物流产组取服药(米非司酮配伍米索前列醇)第3天排出的绒毛和蜕膜组织,对照组取负压吸引出的绒毛和蜕膜组织。采用免疫组化法测定绒毛和蜕膜组织中FN的表达。结果对照组绒毛和蜕膜FN的阳性表达率明显高于两药物流产组(P〈0.017);其中,不完全流产组绒毛和蜕膜组织中FN的阳性表达率高于完全流产组(P〈0.017)。结论米非司酮可通过降低早孕妇女绒毛和蜕膜中FN的表达,改变胚胎宫内发育的内环境,在细胞外基质水平发挥抗早孕的作用。 相似文献
145.
146.
Visual identification of bacterially contaminated red cells 总被引:1,自引:0,他引:1
There have been increasing numbers of reports of transfusion-acquired Yersinia enterocolitica bacteremia (including several fatal cases). Fifteen units of whole blood were inoculated with various concentrations of Y. enterocolitica serotype 0:3 and processed into AS-3 preserved red cells (RBCs). Consistent growth of the organism was found at inoculum concentrations greater than or equal to 10 colony-forming units per mL. In all 13 units of RBCs that supported the growth of Y. enterocolitica, a darkening in color (due to hemolysis and a decrease in pO2) was observed in the bag. The attached sample segments, which were sealed from the main unit, remained sterile and did not darken. This color change was apparent in all the contaminated units by Day 35, which was 1.5 to 2 weeks after the bacteria were first detected in cultures of the blood. Hence, by comparison of the color of the segment tubing with that of the unit itself, units grossly contaminated with Y. enterocolitica can be identified prior to transfusion. Moreover, review of photographs on file at the Centers for Disease Control revealed this dramatic color change in 2 units of blood that caused transfusion-transmitted sepsis (Enterobacter agglomerans and an unidentified gram-negative bacillus, not Yersinia sp.), which demonstrated that the color change was not limited to Y. enterocolitica. This method of visual identification of contaminated units of blood could decrease the incidence of posttransfusion bacterial sepsis. 相似文献
147.
148.
Excessive dorsiflexion (dorsal tilting) of the lunate on a lateral wrist radiograph can be an important sign of carpal injury. Lunate dorsiflexion is a well-recognized sign of an intercarpal ligamentous injury pattern known as dorsal intercalated segment instability (DISI). It is less well recognized that excessive dorsal tilting of the lunate (DISI configuration) can also be produced by displacement of a scaphoid waist fracture. Since the management and prognosis of displaced scaphoid fractures may be quite different from those for nondisplaced fractures, radiologists can make an important contribution by recognizing dorsal tilting of the lunate and appreciating that it may be an important, indirect sign of scaphoid fracture displacement, which may not be directly visualized with standard wrist radiography. In this setting, computed tomography or complex motion tomography may be helpful for further evaluation of the scaphoid fracture. 相似文献
149.
M. ARICÒ G. NOTO K. LA ROCCA G. PRAVATA A. BIVONA 《Clinical and experimental dermatology》1992,17(5):339-341
Crusted scabies (CrS) is an uncommon occurrence among patients with AIDS. Indeed to date only five cases have been described, all with widespread lesions. A case of localized CrS appearing as a yellowish and crusted plaque on the second right toe is reported in a woman with AIDS. Scraping off the verrucous surface, as well as punch-biopsy revealed many mites within the horny layer. The infestation is related to the cutaneous immune response and thus CrS should be considered an opportunistic infestation in AIDS. The importance of the early diagnosis of CrS in order to prevent disseminated lesions and involvement of other health-care workers is underlined. 相似文献
150.
A new method is proposed to derive the size of the interspecies uncertainty factor (UF) that is toxicologically and statistically based. The method involves quantifying interspecies variation in susceptibility to numerous toxic substances via the use of binary interspecies comparisons that are converted to a 95% UF. This interspecies UF represents an estimate of the upper 95% of the population of 95% prediction intervals (PI) for binary interspecies comparisons within four categories of phylogenetic relatedness (species within genus, genera within family, families within order, orders within class). The 95% interspecies UFs range from a low of 10 for species within genus up to 65 for orders within class. Most mammalian toxicology studies involving mice, rats, cats, dogs, gerbils, and rabbits are orders-within- class categories for human risk assessment and would be provided a 65-fold UF. Larger or smaller interspecies UF values could be selected on the level of protection desired. 相似文献