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71.
人脑外伤后皮层核因子-κB的表达 总被引:5,自引:0,他引:5
目的 探讨核因子-κB(nuclear factor—κB,NF—κB)在人创伤性脑损伤(traumatic brain injury,TBI)后挫伤皮层中的表达情况,包括表达位置、表达强度和表达时相。方法 挫伤区皮层的标本来自24例TBI患者,取样时间为伤后5h-5d,利用凝胶电泳迁移分析法(electrophoretic mobility shift assay,EMSA)和免疫组化技术测定NF—κB的活性和表达强度。结果 在人TBI后的挫伤区皮层中,NF—κB表达明显上调,表达高峰为伤后48—72h,NF—κBP65主要在血管内皮细胞和神经胶质细胞中表达,NF—κBP50主要在神经胶质细胞和少量神经元中表达,NF—κBP65的表达强度高于NF—κBP50。结论 NF—κB在人TBI后的挫伤区皮层中表达上调,提示其可能在TBI后的病理生理过程中起着重要作用。 相似文献
72.
Using the whole-cell configuration of the patch clamp technique, calcium-activated potassium currents (IK,Ca) were investigated in ramified murine brain macrophages. In order to induce IK,Ca the intracellular concentration of nominal free Ca2+ was adjusted to 1μM. The Ca2+-activated K+ current of brain macrophages did not show any voltage dependence at test potentials between –120 and +30mV. A tenfold change
in extracellular K+ concentration shifted the reversal potential of IK,Ca by 51mV. The bee venom toxin apamin applied at concentrations of up to 1μM did not affect IK,Ca. Ca2+-activated K+ currents of ramified brain macrophages were highly sensitive to extracellularly applied charybdotoxin (CTX). The half-maximal
effective concentration of CTX was calculated to be 4.3nM. In contrast to CTX, the scorpion toxin kaliotoxin did not inhibit
IK,Ca at concentrations between 1 and 50nM. Tetraethylammonium (TEA) blocked 8.0% of IK,Ca at a concentration of 1mM, whereas 31.4% of current was blocked by 10mM TEA. Several inorganic polyvalent cations were tested
at a concentration of 2mM for their ability to block IK,Ca. La3+ reduced IK,Ca by 72.8%, whereas Cd2+ decreased IK,Ca by 17.4%; in contrast, Ni2+ did not have any effect on IK,Ca. Ba2+ applied at a concentration of 1mM reduced IK,Ca voltage-dependently at hyperpolarizing potentials.
Received: 17 January / Accepted: 5 May 1997 相似文献
73.
74.
I. Hilakivi L. Ahtee J. O. Rinne T. Taira L. M. J. Attila P. Marjamäki 《Journal of neural transmission (Vienna, Austria : 1996)》1995,102(2):139-148
Summary Rats were treated with desipramine 5mg/kg, nomifensine 10mg/kg, zimelidine 25 mg/kg or with 0.9% sodium chloride once a day during the second and third weeks after birth, and brain stem, caudate/putamen and cortical monoamines, and caudate/putamen dopamine D1 (3[H]SCH 23390) and D2 (3[H]spiroperidol) receptor binding were measured when rats were at two months of age. In the brain stem, the concentration of 3-methoxy-4-hydroxy-phenyl glycol was increased in nomifensine rats and the ratio of 5-hydroxyindoleacetic acid to 5-hydroxytryptamine was increased in zimelidine rats. In the caudate/putamen, the concentrations of 3,4-dihydroxyphenylacetic acid and homovanillic acid and the ratio of homovanillic acid to dopamine were increased in desipramine rats; neither3[H]SCH 23390 nor3[H]spiroperidol binding were affected by any of the three monoamine uptake inhibiting antidepressants studied. In the cortex, the ratio of 5-hydroxyindoleacetic acid to 5-hydroxytryptamine was increased in desipramine and zimelidine rats. The findings suggest that desipramine but not nomifensine increases the metabolism of dopamine in the caudate/ putamen and nomifensine but not desipramine increases the metabolism of norepinephrine in the brain stem, and furthermore that the metabolism of serotonin is affected by desipramine as well as by zimelidine. It is possible that also treatment of women with these drugs during late pregnancy causes long-lasting changes in the brain of human fetus. 相似文献
75.
本文在兔MCAO局灶脑缺血模型基础上,利用外源性一氧化氮(NO)前体物质L-精氨酸和NOS抑制剂L-NNA研究NO对脑缺血后脑水肿和脑梗塞的影响。NZW兔42只随机分为7组,每组6只,计对照组、假手术组、MCAO组、MCAO+NS组、MCAO+L-Arg组、MCAO+D-Arg组及MCAO+L-Arg+L-NNA组。结果提示:与单纯MCAO组比较,L-Arg组的脑组织H_2O、Na~+、Ca~(2+)含量明显下降(P<0.01),脑梗塞灶亦明显缩小(P<0.01)。从而显示L-Arg系通过产生NO促使血管舒张而减轻脑水肿和缩小梗塞灶,为临床改进脑缺血的治疗提供依据。 相似文献
76.
Intracranial actinomycosis in juvenile patients
Case report and review of the literature 总被引:1,自引:0,他引:1
F. Puzzilli Maurizio Salvati Andrea Ruggeri Antonino Raco Roberto Bristot Stefano Bastianello Pierpaolo Lunardi 《Child's nervous system》1998,14(9):463-466
A case of actinomycotic brain infection in a juvenile patient is described. Cases of actinomycosis affecting the head and
neck are rare, particularly in juvenile patients. In this case complete resolution of the infection was achieved by means
of surgical treatment and prolonged antibiotic therapy. The authors emphasize the importance of a combined approach for treatment
of this unusual brain infection and stress the difficulties involved in the diagnosis of this pathology.
Received: 3 November 1997 相似文献
77.
肺癌脑转移83例临床分析 总被引:2,自引:0,他引:2
我所内科1988 ̄1993年收治肺癌患者1006例,脑转移83例,占8.25%,由于治疗方法不同,其预后极其不同。手术切除加放疗化疗与单纯放疗化疗的生存率有显著性差异(P〈0.05),放疗化疗综合组疗效预后好于单一治疗组(P〈0.05)。因此在肺癌确诊后应常规作脑影像学检查,可早期诊断,这是提高疗效和生存捏的重要因素。 相似文献
78.
热休克反应对大鼠感染性脑水肿脑组织诱生型一氧化氮合酶mRNA表达的影响 总被引:1,自引:0,他引:1
:探讨热休克反应 (HSR)对百日咳杆菌所致的大鼠感染性脑水肿诱生型一氧化氮合酶 (iNOS)mRNA表达的影响。方法 :从大鼠左侧颈内动脉注入百日咳菌液制备感染性脑水肿 (感脑 )模型 ,采用组织细胞原位杂交技术检测脑组织iNOSmRNA的表达。结果 :生理盐水组、4h感脑组及 4h热休克处理组均未见iNOSmRNA表达 ,8h ,2 4h时感染性脑水肿组均有明显的杂交信号 ,以 2 4h更为明显 ;而 8h ,2 4h热休克处理组仅有少数细胞有阳性信号。结论 :热休克反应对感染性脑水肿的保护作用可能与抑制iNOSmRNA的表达有关 相似文献
79.
Summary 67 cases of brain abscess were analyzed retrospectively. As 2 comatose patients died on admission before any treatment was started, the results are based on 65 treated patients. Different methods of treatment included: total removal in 36 patients, drainage in 14, aspiration in 6 and conservative treatment in 9. Management mortality was 18,5% and was almost not dependent on the method of treatment (except aspiration) being lowest in the drainage group. The mortality was significantly higher in patients with serious impairment of consciousness on admission.Follow-up examination after 1 to 11 years was performed in 47 out of 53 discharged patients and revealed in 25 of them (53%) full recovery. 10 additional cases (21%) are independent. The best early and long term results were obtained in patients by drainage and medical treatment.Chronic epilepsy developed in 34% of patients with supratentorial lesions. The risk of epilepsy was lowest in the group of patients treated by drainage.The authors present the opinion that removal of brain abscess is necessary only in exceptional cases. 相似文献
80.
Groups of male CF-1 mice received 3 and 10 µmol/kg diazepam, lorazepam, and oxazepam intravenously. Between 1 min and 24 h after injection, benzodiazepine concentrations were determined by gas chromatography (GLC) in plasma and in one brain hemisphere; in the other hemisphere, ex vivo benzodiazepine receptor occupancy was measured using3H-flunitrazepam displacement. Based on GLC data, diazepam entered brain rapidly, and was also cleared rapidly, yielding desmethyldiazepam and oxazepam as metabolites in plasma and brain. However, lorazepam and oxazepam entered brain slowly, with brain:plasma equilibrium achieved at 30–60 min; thereafter, the drugs were eliminated from plasma and brain in parallel. The time course and extent of ex vivo occupancy were highly consistent with GLC data (for diazepam, GLC levels were expressed as the sum of diazepam, desmethyldiazepam, and oxazepam, with metabolite concentrations, normalized for molecular weight and for in vitro benzodiazepine receptor affinity.) Between-method correlations were 0.95 or higher. Thus benzodiazepine receptor occupancy is highly dependent on benzodiazepine concentrations in brain. Differences in the time-course of onset and duration of pharmacologic activity between the highly lipophilic benzodiazepine diazepam and the less lipophilic hydroxylated derivatives lorazepam and oxazepam are largely explained by differences in systemic kinetics and in the rate of uptake into brain.Supported in part by grants MH-34223, DA-05258, and AG-00106 from the United States Public Health Service 相似文献