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1.
胰岛素样生长因子1对新生大鼠缺氧缺血性脑损伤保护机制的研究 总被引:1,自引:0,他引:1
目的 建立单侧缺氧缺血性脑损伤 (HIBD)动物模型 ,研究胰岛素样生长因子 1(IGF 1)对HIBD的影响和可能机制。 方法 选择健康 7日龄Wistar大鼠 12 0只 ,建立HIBD模型 ,随机分成假手术组、HIBD组、HIBD后 0 .2mg/kg人基因重组IGF 1干预组 (RH IGF 1组 )、0 .0 6 6mg/kg人基因重组IGF 1干预组 (SRH IGF 1组 )及盐水对照组 (对照组 )。各组按观察时段进一步分为 2 4、4 8、72h组 ,每组 8只。各组于规定时刻观测脑形态学改变、谷氨酸 (Glu)含量、凋亡细胞计数、Bcl 2蛋白表达。 结果 (1)HIBD 4 8h组Glu(116 2 .2± 10 8.1)mg/kg ,较假手术组(75 0 .9± 5 3.4 )mg/kg明显升高 (P <0 .0 5 ) ;HIBD组凋亡细胞计数 [2 4h :(7.6± 1.9) % ,4 8h(12 .6±1.2 ) % ,72h :(13.8± 0 .9) % ],较假手术组 [2 4h(2 .0± 0 .2 ) % ,4 8h(2 .0± 0 .3) % ,72h(2 .0±0 .2 ) % ]明显增加 (P均 <0 .0 5 )。 (2 )与对照组相比 ,RH IGF 1组脑组织病变减轻 ;干预 4 8h组Glu[SRH IGF 1组 (781.4± 5 4 .2 )mg/kg ,RH IGF 1组 (74 0 .5± 4 6 .6 )mg/kg],较对照组 (112 6 .6± 4 8.0 )mg/kg明显降低 (P均 <0 .0 5 ) ;RH IGF 1组凋亡细胞计数 [2 4h :(3.6± 0 .9) % ,4 8h(8.2± 2 .2 ) % ,72h(9.4± 1.4 ) % ],较对 相似文献
2.
Min Zhang Wen-Bin Li Jin-Xia Geng Qing-Jun Li Xiao-Cai Sun Xiao-Hui Xian Jie Qi Shu-Qin Li 《Journal of cerebral blood flow and metabolism》2007,27(7):1352-1368
Glial glutamate transporter-1 (GLT-1) plays an essential role in removing glutamate from the extracellular space and maintaining the glutamate below neurotoxic level in the brain. To explore whether GLT-1 plays a role in the acquisition of brain ischemic tolerance (BIT) induced by cerebral ischemic preconditioning (CIP), the present study was undertaken to observe in vivo changes in the expression of GLT-1 and glial fibrillary acidic protein (GFAP) in the CA1 hippocampus during the induction of BIT, and the effect of dihydrokainate (DHK), an inhibitor of GLT-1, on the acquisition of BIT in rats. Immunohistochemistry for GFAP showed that the processes of astrocytes were prolonged after a CIP 2 days before the lethal ischemic insult, which could protect pyramidal neurons in the CA1 hippocampus against delayed neuronal death induced normally by lethal ischemic insult. The prolonged processes extended into the area between the pyramidal neurons and tightly surrounded them. These changes made the pyramidal layer look like a 'shape grid'. Simultaneously, the prolonged and extended processes showed a great deal of GLT-1. Western blotting analysis showed significant upregulation of GLT-1 expression after the CIP, especially when it was administered 2 days before the subsequent lethal ischemic insult. Neuropathological evaluation by thionin staining showed that DHK dose-dependently blocked the protective role of CIP against delayed neuronal death induced normally by lethal brain ischemia. It might be concluded that the surrounding of pyramidal neurons by astrocytes and upregulation of GLT-1 induced by CIP played an important role in the acquisition of the BIT induced by CIP. 相似文献
3.
α-L-岩藻糖苷酶测定的临床应用 总被引:1,自引:0,他引:1
研究结果表明AFU测定对肝癌的诊断具有较高的敏感性和特异性,其价值优于AFP,两项指标联合检测可提高阳性检出率。动态监测有利于肝癌的早期诊断、鉴别诊断,并可作为转移、复发的指标,也可用于白血病及卵巢癌的诊断。 相似文献
4.
脑囊虫病患者脑脊液中一氧化氮及肿瘤坏死因子α水平研究 总被引:2,自引:1,他引:1
目的 探讨脑囊虫病患者各期脑脊液中的一氧化氮 (NO)、肿瘤坏死因子α(TNF α)的变化规律及它们在脑囊虫病中的作用机制。方法 检测 4 9例明确诊断并依据MR分期 ,单发脑实质内囊虫的脑囊虫病患者和 2 0名对照者脑脊液中NO、TNF α水平。结果 NO在脑囊虫病的Ⅰ期显著降低而TNF α水平呈显著升高 ,NO、TNF α于Ⅱ期、Ⅲ期 (整个退变死亡期 )均表现为高水平 ,Ⅳ期恢复正常 ,NO和TNF α存在高度正相关关系。结论 在单发脑实质内囊虫病中NO、TNF α可能参与杀虫作用 ,其免疫调节与杀虫机制存在着动态平衡 ,参与感染控制 相似文献
5.
目的通过检测子宫内膜异位症(EMs)患者血清及腹腔液中血小板衍生生长因子(PDGF)、血管细胞粘附分子-(VCAM-1)浓度,探讨PDGF和VCAM-1在EMs发病中的作用。方法选取手术后病理证实为EMs的40例患者为EMs组,其中I~II期17例,III~IV23例;非EMs组20例作为对照组。应用酶联免疫吸附法(ELISA)检测血清及腹腔液中PDGF和VCAM-1水平。结果EMs组血清及腹腔液中PDGF、VCAM-1水平均明显高于对照组(P<0.01)。随EMs期别的增加,其血清和腹腔液中PDGF、VCAM-1含量呈上升趋势;EMsIII~IV期水平显著高于I~II期(P<0.05)。EMs患者PDGF与VCAM-1呈正相关性(P<0.05)。结论EMs患者PDGF、VCAM-1表达水平升高,在EMs的发生发展中具有重要作用。 相似文献
6.
7.
颞叶癫痫的临床特点与脑电图分析 总被引:1,自引:0,他引:1
王建茹 《现代电生理学杂志》2003,10(2):65-66
目的:分析颞叶癫痫患的临床特点及脑电图定位的意义。方法:回顾分析92例颞叶癫痫患的脑电图。结果:左颞有癫痫样波42例,右颞有癫痫样波29例,双颞有癫痫样波21例,临床表现与癫痫样波发放部位有关,癫痫波的传导主要有容积传导和神经传导方式。结论:结合患临床表现与脑电图癫痫样波起始部位分析有助于致痫灶的定位。 相似文献
8.
Objective To examine the protective effects of hydroxysafflor yellow A (HSYA) against the senescence of mesenchymal stem cells (MSCs) induced by D-galactose (D-gal) in vitro, and investigate the potential mechanism involved.
Methods Grouping experiment, Normal control (NC) group: conventional culture with complete medium; Senescence group: MSCs were cultured for 48 h with complete medium containing 10 g/L D-gal; HSYA group: on the basis of senescence induction, HSYA with the suitable concentration was used to protect MSCs. The key experimental indices associated with oxidative stress, inflammatory response, cell senescence, proliferation and apoptosis were measured through chemical colorimetry, β-galactosidase staining, EdU incorporation and flow cytometry, respectively. The relative quantity (RQ) of proteins related closely to cell proliferation, apoptosis, and NF-κB signaling were measured by Western blotting.
Results As compared with Senescence group, treatment with HSYA (120 mg/L) effectively ameliorated the adverse situation of MSCs. Oxidation stress and inflammation along with D-Gal induction was dramatically alleviated in MSCs; The β-Gal-positive staining indicated that MSC senescence was significantly mitigated; The proliferative capability of MSCs was significantly increased by up-regulating PCNA and inhibiting p16 expression; The anti-apoptotic effect on MSCs was exerted by down-regulating the RQ of cleaved Caspase-3 and Bax; The activity of NF-κB signaling in MSCs was notably suppressed through inhibiting phosphorylation of IKKβ and p65.
Conclusion HSYA (120 mg/L) significantly delayed the D-Gal-induced senescence process in MSCs through attenuating inflammatory reaction and oxidative stress, and suppressing the activity of NF-κB signaling. 相似文献
9.
ObjectiveTo report our experience in the reconstruction of soft tissue defects in the hand with a free anterolateral thigh deep fascia flap and describe the clinical outcomes.MethodsThis study was a retrospective trial. From November 2016 to January 2020, six patients (four men and two women) with soft tissue defects in the hand were included in this study. The average age of the patients was 33.7 ± 12.7 years (range, 20 to 50 years). All patients underwent reconstructions with free anterolateral thigh deep fascia flaps. Relevant clinical characteristics were recorded prior to surgery. The size and thickness of the deep fascia flap and the thickness of the skin were measured intraoperatively. The survival of the flaps and skin grafts and the occurrence of infection were recorded after the operation. At follow‐up, donor site complications and postoperative effects were evaluated according to the outcome satisfaction scale. The pain in the injured hand was assessed using the visual analog scale.ResultsThe average body mass index (BMI) was 26.6 ± 1.7 kg/m2 (range, 23.9 to 28.7 kg/m2). The defect sizes ranged from 5 cm × 5 cm to 13 cm × 8 cm (average, 53.1 ± 27.9 cm2). The six anterolateral thigh deep fascia flaps ranged from 7 cm × 6 cm to 14 cm × 9 cm in size (average, 71.8 ± 29.1 cm2). The thicknesses of skin ranged from 25 mm to 40 mm (average, 32.5 ± 4.8 mm), and the thicknesses of the deep fascia flaps ranged from 2 mm to 3 mm (average, 2.5 ± 0.5 mm). After the operation, the blood supply of the deep fascia flap was normal in all cases. The second‐stage skin grafts of most patients survived completely. The skin graft in one case was partially necrotic and healed after a dressing change. No infection occurred. At follow‐up (average, 16.3 ± 6.9 months), there was only a linear scar and no loss of sensation at the donor site of each patient. According to the outcome satisfaction scale, the outcome satisfaction score ranged from 6 to 8 (average, 7.2 ± 0.9), all of which were satisfactory. Apart from one patient who reported mild pain, all the other patients reported no pain. Three typical cases are presented in this article.ConclusionsThe free anterolateral thigh deep fascia flap, which is suitable for reconstruction of soft tissue defects in the hand, can provide very good outcomes both functionally and aesthetically. 相似文献
10.
目的 探讨喉部分切除术对声门型喉癌T3 病变的可行性及修复材料的选择。方法 对 1986年 1月~ 1994年 1月 78例行喉部分切除术的声门型喉癌T3 病变患者的术式及修复方法进行了回顾性分析。结果 患者 3年、5年生存率分别为 88 5 %、75 6 % ,局部复发率 15 4%。应用了梨状窝粘膜 甲状软骨板外侧软骨膜、会厌软骨瓣及带状肌双肌双蒂瓣 3种方法修复创面 ,均获得了较好的喉功能恢复。结论 喉部分切除术是根治声门型喉癌T3 病变合理、有效的方式 ,但不能完全替代全喉切除术 ,应根据切除范围选择合理的修复方式。 相似文献