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51.
为探讨脊髓损伤后运动神经元及神经胶质细胞内神经生长因子(NGF)及其高亲和力受体(TrkA)表达的变化,用改良Allen重击法损伤SCI组动物T12脊髓,按伤后存活时间再将动物分为脊髓损1 d组、2 d组和5 d组。各组动物的脊髓切片经ABC法免疫组织化学染色,用光镜观察TrkA及NGF在脊髓前角运动神经元表达的变化和胶质纤维酸性蛋白(GFAP)及NGF免疫反应阳性胶质细胞的反应性增生程度,并进行图像分析。结果显示:脊髓损伤后前角运动神经元TrkA及NGF的表达随脊髓损伤后动物存活时间的延长逐渐上调;脊髓白质和灰质内尤其是皮质脊髓束内GFAP及NGF阳性胶质细胞明显增生;与此同时,室管膜细胞内亦可见明显的NGF免疫反应产物。上述结果表明,脊髓损伤可刺激脊髓前角运动神经元表达TrkA及NGF,通过自分泌维持受损神经元的存活;损伤部位反应性增生的胶质细胞亦可产生NGF,通过旁分泌作用于脊髓前角运动神经元或皮质脊髓束的轴突末梢,以维持运动神经元的存活及促进皮质脊髓束的再生;适时补充外源性神经营养素或改变损伤局部的微环境将有利于受损脊髓的修复和再生。  相似文献   
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为了解白细胞介素 - 8的体内行为 ,用 Bolton- Hunter法对 IL- 8进行 1 2 5I标记 ,并测定它在小鼠体内的分布 ;得到了 1 2 5I- IL- 8在小鼠血、心、肝、肺、肾、骨、脾等脏器中的分布以及它在血液中的快相半排期 T1 /2α为 0 .3 2 h和慢相半排期 T1 /2β为 8.0 1h。1 2 5I- IL- 8主要通过肾排除  相似文献   
55.
Wei H  Qin ZH  Senatorov VV  Wei W  Wang Y  Qian Y  Chuang DM 《Neuroscience》2001,106(3):603-612
Huntington's disease is a progressive, inherited neurodegenerative disorder characterized by the loss of subsets of neurons primarily in the striatum. In this study, we assessed the neuroprotective effect of lithium against striatal lesion formation in a rat model of Huntington's disease in which quinolinic acid was unilaterally infused into the striatum. For this purpose, we used a dopamine receptor autoradiography and glutamic acid decarboxylase mRNA in situ hybridization analysis, methods previously shown to be adequate for quantitative analysis of the excitotoxin-induced striatal lesion size.Here we demonstrated that subcutaneous injections of LiCl for 16 days prior to quinolinic acid infusion considerably reduced the size of quinolinic acid-induced striatal lesion. Furthermore, these lithium pre-treatments also decreased the number of striatal neurons labeled with the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay. Immunohistochemistry and western blotting demonstrated that lithium-elicited neuroprotection was associated with an increase in Bcl-2 protein levels.Our results raise the possibility that lithium may be considered as a neuroprotective agent in treatment of neurodegenerative diseases such as Huntington's disease.  相似文献   
56.
Cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) is important for downregulation of T-cell activation, and CTLA-4 gene polymorphisms have been implicated as risk factors for rheumatoid arthritis (RA). Previous studies of the association between the +49 polymorphism of the CTLA-4 gene in RA have provided conflicting results. In order to determine association of the CTLA-4 gene with RA in Chinese Han population, we used denaturing gradient gel electrophoresis (DGGE) to genotype polymorphisms of four SNPs (MH30, +49, CT60 and JO31) of the CTLA-4 gene in 326 RA patients and 250 healthy controls. Furthermore, meta-analysis of all available studies relating +49 polymorphism to the risk of RA was performed to confirm the disease association. Among the SNPs examined, the genotype frequencies of CTLA-4 +49 and CT60 in RA patients differed significantly from controls (P=0.028 and 0.007). In addition, the distribution of four haplotypes constructed by these two SNPs was significantly different between patients and controls (chi(2)=10.58, d.f. =3, P=0.014). The meta-analysis also revealed that in both European and Asian populations, the CLTA-4 +49 G allele was associated with the risk of RA. These results suggested that the CTLA-4 gene might be involved in the susceptibility to RA in the Chinese Han population and both +49 and CT60 of CTLA-4 gene might be the causal variants in RA disease.  相似文献   
57.
目的应用rhlL-18在体外培养系统(Coculture system in vitro,CCs)中诱导快速肿瘤杀伤效应及诱导肿瘤特异性细胞毒性T淋巴细胞(Cytotoxic T Lymphocyte,CTL)。方法 采用StemSep^TM免疫磁性细胞分离法分离人外周血NK细胞、T细胞及树突细胞(DCs),流式细胞仪分析细胞表型,125I-UdR标记的细胞毒实验检测杀伤活性,ELISA方法检测IFN-7的产生量。结果 在CCs中,rhIL-18诱导出快速肿瘤杀伤效应,这种杀伤效应无抗原特异性、不受MHC限制,DCs和T细胞的存在与否对其无明显影响。在同一培养系统中,肿瘤抗原存在的条件下,96h后,rhIL-18能够诱导并促进CTL介导的肿瘤特异性杀伤效应。结论 rhIL-18能够在体外培养系统中相继诱导肿瘤快速杀伤效应及肿瘤特异性CTL。  相似文献   
58.
OBJECTIVE: To investigate the relationship between the plasminogen activator inhibitor (PAI-1) polymorphisms and endometrial hypoplasia in infertile women. METHODS: The study was conducted in 105 primary infertile patients with endometrial hypoplasia diagnosed by pathology and the thickness of endometrium by B-mode ultrasound and 85 controls who were not pregnant and had normal fertility. The -675 4G/5G polymorphism in the PAI-1 gene was detected by polymerase chain reaction-restriction fragment length polymerphim analysis. RESULTS: The frequencies of 4G/4G genotype and 4G allele of the PAI-1 gene were higher in the patient group (48.6% and 66.2%) than in the normal controls (22.4% and 47.1%) (P < 0.01). ThePAI-1 4G/4G genotype was significantly associated with endometrial hypoplasia in the infertile patients (OR=4.9, 95% CI: 2.10-10.12). CONCLUSION: The present findings suggest that the 4G/5G polymorphism of the PAI-1 gene was associated with endometrial hypoplasia in infertile patients.  相似文献   
59.
Enhancement of S-antigen and its mRNA in the irides of uveitic patients   总被引:1,自引:0,他引:1  
S-antigen (S-Ag) and its mRNA were analysed by immunohistochemistry and in situ hybridization in 32 iridectomy specimens from 29 uveitic patients and 10 non-uveitic patients. S-Ag was detected in one iris and its mRNA was detected in 12 uveitic patients. Neither S-Ag nor its mRNA was found in the controls (P < 0.003). Ten of the 12 patients who had detectable S-Ag mRNA, while only four of the 17 patients who did not, had received corticosteroids for more than 3 years (P = 0.006). We also demonstrated S-Ag and its mRNA in bovine iris by immunoprecipitation and polymerase chain reaction. These results indicate that S-Ag and its mRNA accumulate in the irides of some uveitic patients. This accumulation may be the result of local immunoregulatory factors and an effect of corticosteroid treatment, and may modulate ocular inflammation.  相似文献   
60.
"Spontaneous" remission of leukemia has been observed in both humans and animals. Bierman et al2 in 1953 reported 11 cases of remis- sion in acute lymphoblastic leukemia (ALL) of childhood following acute infectious disease. In 1979 we saw a case of ALL remission in a child following a severe attack of respiratory infection.  相似文献   
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