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91.
目的:观察1,6二磷酸果糖(FDP)对血肿周围组织能量代谢的影响。方法:健康大耳白兔随机分成正常组,假手术组,脑出血组和治疗组,其中后3组又按各时间点分成1、6、12、24、48和72h组。两次注血法制作脑出血模型,测定各时点血肿周围组织乳酸含量、三磷酸腺苷(ATP)含量和磷酸果糖激酶(PFK)活性。结果:脑出血组24h后ATP含量有明显下降,治疗组ATP含量明显增高。1、6、12h治疗组乳酸含量降低,且治疗组乳酸峰值延迟至24h。治疗组PFK活性均高于脑出血组。结论:FDP可改善血肿周围组织的能量代谢。 相似文献
92.
93.
Inflammatory biomarkers in blood of patients with acute brain ischemia 总被引:11,自引:0,他引:11
S. Sotgiu B. Zanda B. Marchetti M. L. Fois G. Arru G. M. Pes F. S. Salaris A. Arru A. Pirisi G. Rosati 《European journal of neurology》2006,13(5):505-513
Although many failed surrogate markers are provided in the literature, inflammation may contribute to the outcome of ischemic stroke. In 50 consecutive patients with acute ischemic stroke, in the absence of symptoms and signs of concomitant infection, we evaluated a panel of biomarkers reported to be variably associated with brain ischemia, and correlate their serum level with the brain lesion volume and clinical outcome. Infarct size was calculated on computed tomography (CT) scans by means of the Cavalieri's method. Neurological impairment was scored by using the Glasgow Coma Scale, Glasgow Outcome Scale and National Institutes of Health (NIH) scales at stroke onset and 3-month follow-up. Some markers showed a direct significant correlation with both initial and final NIH scale and with infarct size, particularly tumor necrosis factor alpha (TNF-alpha) (P=0.002), intercellular adhesion molecule-1 (P<0.01) and matrix metalloproteinase-2/9 (P=0.001). In contrast to previous reports, interleukin-6 (IL-6) serum level showed a significant inverse correlation with both final neurological impairment and infarct size (P<0.001). This novel finding allows us suggesting that IL-6, in the context of a complex pro-inflammatory network occurring during stroke, is associated with neuroprotection rather than neurotoxicity in patients with ischemic brain injury. 相似文献
94.
目的:探讨IL-6对人精子顶体反应(AR)的影响机制。方法:采用BAEE/ADH法测定精子顶体酶的活性,以及通过FITC-PSA法检测精子顶体反应。结果:IL-6可诱导精子顶体酶及超氧化物歧化酶(SOD)的活性,促进精子顶体反应;胞外Ca2+单独不能诱导精子顶体反应,且没有胞外Ca2+的参与,IL-6也不能诱导精子顶体反应;蛋白激酶C(PKC)抑制剂calphC能逆转IL-6诱导的精子顶体反应。结论:IL-6对精子顶体反应有一定的促进作用,可能通过诱导精子的顶体酶和SOD活性等途径来实现,在此作用中,也涉及了PKC的激活,且还需要外源性Ca2+的参与。 相似文献
95.
应用小鼠骨髓细胞长周期培养(LTBMC)体系,观察重组人白细胞介素-1α(rhIL-1α)对造血细胞增殖的影响。结果显示,经rhlL-1α作用后,小鼠LTBMC中悬浮细胞数增多,其中粒单系祖细胞(CFU-GM)数量也明显增加,维持时间延长。表明rhIL-1α能促进小鼠造血细胞在体外LTBMC中增殖并分化,而且与剂量有关系。rhIL-1α加入的时间,以骨髓细胞2次接种时同时加入为好,延迟加入则作用减弱。本实验对骨髓干、祖细胞体外扩增和自体骨髓移植等方面的研究有一定意义。 相似文献
96.
R. D. Myers F. J. Lopez-Valpuesta F. J. Minano M. H. Wooten V. S. Barwick S. D. Wolpe 《Journal of neuroscience research》1994,39(1):31-37
The chemokines, macrophage inflammatory protein-1 (MIP-1) and its subunit MIP-1β, induce an intense fever in the rat when they are injected directly into the anterior hypothalamic, pre-optic area (AH/POA), a region containing thermosensitive neurons. The purpose of this study was to compare the central action on body temperature (Tb) of MIP-1β with that of interleukin-6 (IL-6), which also has been implicated in the cerebral mechanism underlying the pathogenesis of fever. Following the stereotaxic implantation in the AH/POA of guide cannulae for repeated micro-injections, radio transmitters which monitor Tb continuously were inserted intraperitoneally in each of 15 male Sprague-Dawley rats. Each micro-injection was made in a site in the AH/POA in a volume of 1.0 μl of pyrogen-free artificial CSF, recombinant murine MIP-1β, or recombinant human IL-6. MIP-1β in a dose of 25 pg evoked an intense fever characterized by a short latency, a mean maximum rise in Tb of 2.4 ± 0.21°C reached by 3.7 ± 0.42 hr, and a duration exceeding 6.5 hr. Injected into homologous sites in the AH/POA, IL-6 induced a dose dependent fever of similar latency and a mean maximal increase in Tb of 1.2 ± 0.25°C, 1.8 ± 0.15°C, and 2.1 ± 0.22°C and duration of 6.2 ± 1.28 hr, 6.7 ± 0.49 hr, and 6.8 ± 0.65 hr when given in doses of 25, 50, and 100 ng, respectively. These results show that MIP-1β and the highest dose of IL-6 induce a fever of comparable intensity, but MIP-1β exerts its action in a much lower concentration. Thus, the de novo synthesis and subsequent action of the MIP-1 family of cytokines on neurons of the AH/POA in response to a pyrogen challenge apparently play a functional role in the pathogenesis of fever. Further, the endogenous activity of IL-6 in the hypothalamus which is enhanced in response to a lipopolysaccharide also may reflect its essential part in the acute phase response to a bacterial challenge. Copyright © 1994 Wiley-Liss, Inc. 相似文献
97.
用短波紫外线照射患儿腰背部皮肤辅助治疗小儿肺炎,提示紫外线治疗组与对照组相比,显著缩短患儿发热。咳嗽及肺部湿罗音消失时间(P<0.01)。用化学发光法测定中性粒细胞吞噬功能,治疗组患儿血液内中性粗细胞吞噬功能显著提高(P<0.05)。同时测定治疗组患儿血中IL-2低于对照组(P<0.05),并对上述结果机理进行了探讨。 相似文献
98.
胃癌患者红细胞免疫功能的变化 总被引:4,自引:1,他引:3
运用简单形态学方法测定了30例胃癌患者红细胞免疫功能,结果表明:胃癌患者红细胞C3b受体花环率及肿瘤红细胞花环率显著低于正常对照(P<0.01)及慢性良性胃病患者(P<0.01),而免疫复合物花环率则高于正常人(P<0.01)及慢性良性胃病患者(P<0.01);Ⅲ、Ⅳ期胃癌患者肿瘤红细胞复合物花环率明于低于Ⅰ、Ⅱ期患者(P<0.01);贲门癌肿瘤红细胞花环率显著低于胃窦(体)癌患者(P<0.01) 相似文献
99.
Unilateral lesion of the nigrostriatal pathway decreases the firing rate and alters the firing pattern of globus pallidus neurons in the rat 总被引:2,自引:0,他引:2
Activities of spontaneously firing neurons in the globus pallidus of intact rats and rats that survived unilateral lesions of the nigrostriatal pathway for 3 days, 1 week, or 6-11 weeks were compared. No significant differences in neuronal firing rate, firing pattern, and number of cells per pass were observed between chloral hydrate-anesthetized control and lesioned animals. However, in locally anesthetized animals, pallidal cells fired significantly faster than in chloral hydrate-anesthetized animals, and the lesion caused a decrease in the firing rates of pallidal cells 1 week and 6-9 weeks postlesion. In addition, significant differences in the firing pattern of pallidal cells, as determined by the ratio of the mean to median interspike intervals, were seen between locally anesthetized controls and animals surviving 3 days, 1 week, and 6-9 weeks postlesion. This altered firing pattern tended to return to normal with time. The number of cells per pass was not significantly altered by the lesion. Data from this study suggest that, in locally anesthetized animals, the removal of the tonic dopaminergic input to the basal ganglia causes pallidal cells to decrease their firing rates in a time-dependent fashion and causes reversable firing pattern changes. This suggests that tonically active dopamine neurons, probably acting through the striatopallidal pathway, regulate the firing rate and mechanisms controlling the temporal ordering of spontaneous discharges of globus pallidus neurons. 相似文献