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51.
缺氧缺血性脑病新生鼠补钙前后脑细胞,红细胞内外钙的变化 总被引:31,自引:0,他引:31
为了观察一般剂量补钙对缺氧缺血性脑病(HIE)脑细胞和红细胞内外钙变化的影响,以探讨HIE时补钙是否增加脑细胞钙超载,用HIE新生动物模型进行了实验研究,结果表明:(1)缺氧缺血时红细胞、脑细胞及脑组织出现钙积聚;(2)补钙后,血浆总钙浓度明显升高,而脑细胞、脑组织及红细胞钙积聚并未加重;(3)血浆总钙浓度与脑细胞或红细胞胞浆游离钙离子浓度无相关关系。提示:(1)HIE时钙内流可能是全身性的;(2)对HIE并低钙血症患儿吸氧后一般剂量补钙可能是安全的。 相似文献
52.
羧乙基锗倍半氧化物对大鼠脑缺血再灌注损伤的保护作用 总被引:7,自引:0,他引:7
采用结扎双侧颈总动脉后再通的方法复制大鼠脑缺血再灌注损伤模型,通过测定再灌注后大鼠海马组织中脂质过氧化产物丙二醛(MDA),超氧化物歧化酶(SOD)与谷胱甘肽过氧化物酶(GSH—Px)及ATPase的活性,观察了有机锗─羧乙基锗倍半氧化物(CGS)对大鼠脑缺血再灌注后大鼠海马组织中MDA水平,明显保护SOD、GSH─Px、Na+K+─ATPase及Ca2+─AT─Pase活性。表明CGS对大鼠脑缺血再灌注损伤具有保护作用。 相似文献
53.
笔者对13例良性小脑出血的患者,从起病、临床表现进行了具体分析.总结出中老年良性小脑出血的6个特点,供临床工作者参考. 相似文献
54.
急性脑血管病肿瘤坏死因子-α的临床研究 总被引:1,自引:0,他引:1
目的:探讨肿瘤坏死因子-α(TNF-α)在急性脑血管病(ACVD)中的作用及其变化的临床意义。方法:选取95例ACVD患者,并设性别及年龄相匹配的血清对照组(20例)及脑脊液对照组(10例)。应用酶联免疫吸附法(ELISA)于发病后第1、3、7、14d测定血清和脑脊液中TNF-α。结果:①三种脑血管病患者血清TNF-α动态变化存在差异,脑出血和脑梗死组的峰值单间为发病后第3d,而蛛网膜下腔出血(SAH)组为第1d。②脑梗死患者血清TNF-α水平与梗死面积、神经功能缺损程度及病情恶化与否相关。③SAH组于发病后第1d、3d、7d脑脊液TNF-α值高于血清,14d时降至对照组水平并与血清无差异。结论:①脑梗死患者血清TNF-α的动态观察,可为临床预测梗死灶大小、神经功能缺损程度及病情恶化与否提供依据。②发病早期的脑梗死患者若CT未能显示病灶时,血清TNF-α的明显升高有助于临床诊断和治疗。③SAH患者脑脊液中TNF-α水平明显高于血清,进一步提示脑内神经组织可产生TNF-α。脑脊液中TNF-α的持续明显升高可能与SAH后脑血管痉挛有关。④TNF-α参与了ACVD的炎性反应过程,早期抑制TNF产生及抗炎性反应的治疗可能具有潜在的临床价值。 相似文献
55.
Patients at Boston's Children's Hospital diagnosed as having cerebral palsy were filmed walking. These films were digitized and translated into measurements associated with leg motion. In this paper we use the gait measurements of 128 such patients to illustrate that the kth nearest neighbour clustering procedure results in a gait typology for patients with cerebral palsy. The procedure identifies four subpopulations from the sample data; the membership of a patient within this typology is mostly determined by the patient's motor control. The developed typology differs from the present diagnostic system which classifies a cerebral palsy patient as either quadriplegic, diaplegic or hemiplegic. 相似文献
56.
老年脑梗死患者急性期血小板活化功能定量检测 总被引:11,自引:2,他引:9
目的 :探讨老年脑梗死患者外周血中血小板膜糖蛋白变化的临床意义。 方法 :应用流式细胞术检测了 6 8例急性期老年脑梗死患者外周血血小板活化分子标记物CD4 1、CD6 2p和CD6 3的含量水平 ,与 4 2例正常老年人对照 ;并对脑梗死组病灶大小、梗死部位、病情分级等与血小板活化分子表达的变化进行分析 ,应用统计学进行处理。 结果 :急性期脑梗死患者血小板粘附分子CD4 1、CD6 2 p和CD6 3的表达水平显著高于正常对照组 (P <0 .0 1) ,且与梗死灶大小及病情分级密切相关 ,与梗死部位无关。 结论 :老年脑梗死患者急性期外周血血小板活化功能明显增强 ,为早期应用抗血小板聚集药物的治疗提供了实验依据 相似文献
57.
Gordon J. Harris Ph.D. Instructor Jonathan M. Links Ph.D. Associate Professor Godfrey D. Pearlson M.B. B.S. Director Edwaldo E. Camargo M.D. Associate Professor 《Psychiatry research》1991,40(3):167-180
We developed a semiautomatic method termed “cortical circumferential profiling” for objective analysis of cerebral cortex function in emission tomographic neuroimaging studies. This method treats cortex as a continuous ring near the outer brain edge. A computer algorithm samples the cortex at 60 contiguous, equiangular locations, using 1-cm2 samples. These values are plotted as a function of cortical angle to produce the cortical circumferential profile. This method was used in a study of regional cerebral perfusion in 15 patients with Alzheimer's disease and 8 elderly control subjects using N-isopropyl [I-123]-iodoamphetamine. Cortical circumferential profiling decreases variability, examines the entire cortex within slices at preselected levels above the orbital-meatal line, and facilitates intrasubject and intersubject comparisons. 相似文献
58.
Intraventricular hemorrhage (IVH) in preterm infants is well known to be associated with the high morbidity and mortality of this group. Previous studies have suggested altered cerebral blood flow (CBF) as an important pathologic factor. We measured the CBF in nearterm rabbit fetuses using the hydrogen clearance technique. The local CBF of the rabbit fetuses was significantly low compared with that of the maternal rabbits. The response of CBF to changes in PaCO2 was observed in rabbit fetuses. The CO2 reactivity index of the fetal rabbit was lower than that of the maternal rabbit. This low CO2 reactivity might reflect the immaturity of the fetal brain and its low CBF. We were unable to monitor the fetal blood pressure, but the fetal CBF remained stable when the maternal blood pressure was altered. It is well known that IVH in preterm infants originates from the subependymal germinal matrix and that this has many fragile vessels. Our observation suggests that even a small increase of CBF during hypercapnia might have a large effect towards producing hemorrhage. 相似文献
59.
60.
Johannes Woitzik Elke Lassel Ulf C. Schneider Helmut Schroeck Rudolf Graf 《Experimental neurology》2009,218(1):41-350
Lesion evolution during focal cerebral ischemia may depend on flow restrictions or on accumulation of toxic mediators within the infarct and expansion of these factors to the periinfarct region. So far, the precise contribution of flow dependent versus spreading-mediated impairment of viable periinfarct tissue has not been determined. Therefore, we measured lesion expansion, flow restrictions and glutamate distribution on serial brain sections at different time points after experimental focal ischemia.Permanent focal ischemia was induced by occlusion of the right middle cerebral artery in male rats and the flow reduction was subsequently measured at 1, 12 and 24 h using iodo[14C]antipyrine autoradiography. Additionally, the necrotic volume was determined on serial brain sections and the glutamate content was measured in tissue samples from adjacent microdissections.Twelve hours after focal ischemia no noteworthy viable areas with blood flow restrictions of 20-40 ml 100 g− 1 min− 1 existed but at 24 h the necrotic tissue exceeded the hemodynamically compromised region by 40 ± 21 mm3 (24%). Furthermore, at 12 and 24 h the glutamate content was elevated in areas surrounding the infarct.Relevant flow restrictions are detectable only during early stages of infarct maturation, whereas the propagation of secondary factors may be the predominant mechanism for delayed infarct evolution. 相似文献