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51.
目的 :检测脑血管性痴呆患者血清中可溶性白细胞介素 - 2 (s IL- 2 R)水平 ,评价 s IL- 2 R的测定在诊治脑血管性痴呆中的价值。方法 :采用双抗体夹心的 EL ISA法检测脑血管性痴呆患者血清中 s IL- 2 R的水平。结果 :脑血管性痴呆患者血清中的 s IL- 2 R水平较健康对照组显著增高 ,两组比较差异非常显著 (P <0 .0 1)。结论 :检测脑血管性痴呆患者血清中 s IL- 2 R水平 ,有助于了解患者的免疫功能变化及疗效观察 相似文献
52.
目的 :为满足基因治疗的需要构建人白细胞介素 12 (hIL 12 )双亚基共表达质粒。方法 :先从人胚肾组织的逆转录产物中用PCR方法扩增出它的两个亚基P4 0 和P3 5的cDNA全长 ,分别克隆入真核表达载体pcDNA3.1(+/ )中构建单亚基质粒———P(+) /P4 0 和P( ) /P3 5,然后再将二者串联克隆入真核表达载体 pcDNA3.1(+)中得到P(+) /IL 12质粒。脂质体转染HepG2后 2 4,48hELISA检测细胞培养上清内hIL 12蛋白质表达。结果 :P(+) /IL 12质粒经酶切和测序证明两亚基连接方向正确 ,序列无突变 ;ELISA检测细胞上清结果证实可表达hIL 12蛋白质。结论 :成功构建P4 0 和P3 5双亚基真核共表达质粒———P(+) /IL 12 ,为模拟hIL 12生理表达方式 ,简化hIL 12基因治疗操作奠定了基础。 相似文献
53.
选用产期接近的3月龄小尾寒羊30只,随机分为二组(试验Ⅰ、试验Ⅱ),每组15只。试验Ⅰ饲喂本场加工的羔羊精饲料,试验Ⅱ饲喂本场加工的羔羊精饲料基础上,每公斤饲料中分别添加钴0.4mg和维生素B120.30mg,试验结果表明:试验Ⅰ与试验Ⅱ日增重相比差异极显著(P<0.01)。 相似文献
54.
Abstract: The vitamin B12 (VB12) parameter was studied in the serum and cerebrospinal fluid (CSF) of 14 demented patients. Eleven of these patients were in a state of dementia of the degenerative type such as Alzheimer's disease, senile dementia and Pick's disease. The serum VB12 concentration in all the patients was within normal limits, I.e. 500–1,300 pg/ml. There was no significant difference between the CSF-VBl2 levels and the severity of dementia. The serum and CSF-VB12 levels of the demented patients did not show any significant elevation after the oral administration of CH3–Bl2, 2 mg per day. On the other hand, there was a marked elevation of both the serum and CSF-VB12 after an oral medication (2 mg per day) plus intramuscular administrations (500 μg per day). These results confirm that the intramuscular administration of CH3–B12 is an effective way to get a higher value of the serum and CSF-VB12 levels. 相似文献
55.
内皮细胞生长因子诱导大鼠血管内皮细胞增殖过程中FKBP12的表达 总被引:1,自引:1,他引:0
目的探讨内皮细胞生长因子(Endothelial cell growth factor,ECGF)诱导的血管内皮细胞(Vascular endothelial cell,VEC)增殖过程中FK506结合蛋白12(FK506 binding protein 12,FKBP12)表达的变化,为VEC的鉴定提供新的方法。方法培养大鼠VEC并传代。倒置显微镜下观察其在ECGF作用下的增殖情况,检测Ⅷ因子相关抗原、FKBP12和不同时期FKBP12 mRNA水平的表达。结果VEC表达FKBP12;VEC传代后第4天FKBP12 mRNA表达水平达到最高,6—8d下降。结论FKBP12既可作为VEC的标志物,又可反映VEC的增殖情况。 相似文献
56.
白细胞介素-12基因修饰对树突状细胞表面分子表达及细胞因子分泌的影响 总被引:1,自引:0,他引:1
目的 观察白细胞介素(IL)-12基因修饰对树突状细胞(DC)表面分子及细胞因子分泌的影响.方法 采用重组逆转录病毒介导IL-12基因修饰人外周血单个核细胞(PBMC)来源的Dc;ELISA法检测各组DCs和各组T细胞上清中IL-12、IL-10、IFN-γ因子的分泌水平;流式细胞仪(FACS)分析各组DC表面CD83、CD86的表达;MTT法检测DC刺激同源T淋巴细胞增殖的能力;统计学分析比较各组间的差异.结果 IL-12基因修饰使得DC高表达CD83和CD86分子,分泌高水平IL-12及IFN-γ,但对IL-10因子的分泌无明显影响,刺激同源T淋巴细胞增殖明显,诱导激活的T细胞上清中IFN-γ水平显著增高、IL-10分泌水平显著降低.结论 经IL-12基因修饰后的DC表型成熟,分泌IL-12及IFN-γ的能力增强,对IL-10因子的分泌无影响,能抑制T细胞分泌IL-10因子,优化抗原提呈的微环境. 相似文献
57.
Biological properties of interleukin-12 and its therapeutic use in persistent hepatitis B virus and hepatitis C virus infection 总被引:2,自引:0,他引:2
Summary. Interleukin (IL)-12 is a pleiotropic cytokine produced by antigen-presenting cells in response to diverse stimuli. IL-12 is a key molecule in the regulation of host's immune responses. In particular, IL-12 influences the balance between the T-helper cells type 1 (TH1 ) and type 2 (TH2 ); it modulates macrophage responses through the control of interferon-gamma synthesis by TH1 cells; and, suppresses IgE class antibody production (has a suppressive effect on allergic reactions) and promotes a shift in the IgG subclasses. IL-12 enhances resistance to several infectious diseases, is a powerful antitumor agent in vivo , and acts as a vaccine adjuvant. The biological properties of IL-12 point to the potential therapeutic use in persistent hepatitis B virus and hepatitis C virus infection. 相似文献
58.
Marlon Normandin Joel Gagn Julie Bernard Robert lie Dom Miceli Michel Baudry Guy Massicotte 《Brain research》1996,730(1-2):40-46
Low-frequency stimulation is associated with long-term depression (LTD) of synaptic efficacy in various brain structures. Like long-term potentiation (LTP), homosynaptic LTD in area CA1 of the hippocampus appears to require NMDA receptor activation, changes in postsynaptic calcium concentration and phospholipase A2 (PLA2) activation. Arachidonic acid (AA) is released after the activation of calcium-dependent phospholipases and free AA is rapidly metabolized to a family of bioactive products (the eicosanoids) which are thought to be both intracellular and extracellular messengers. In the present study, we investigated the involvement of the cyclooxygenase and lipoxygenase pathways of AA metabolism in the formation of homosynaptic LTD in the rat hippocampus. Stimulation at 1 Hz for 15 min was used to produce homosynaptic depression in area CA1 of hippocampal slices. LTD induction was partially blocked by bromophenacyl bromide (50–100 μM), a selective PLA2 inhibitor, and by the a nonselective lipoxygenase inhibitor nordihydroguaiaretic acid (NDGA; 100 μM). In contrast, the specific cyclooxygenase blocker indomethacin (100 μM) did not significantly reduce hippocampal LTD. Since NDGA interferes with LTD formation, we examined whether specific inhibitors of 5- and 12-lipoxygenases were capable of blocking LTD expression. The 12-lipoxygenase inhibitor baicalein at a concentration of 50 μM reduced LTP formation when given in the bath, an effect that was less pronounced with the 5-lipoxygenase inhibitor AA-861. These data suggest that the activation of endogenous PLA2 and the formation of 12-lipoxygenase metabolites of AA may be important factors controlling the expression of hippocampal LTD. 相似文献
59.
Chromaffin cells of the adrenal medulla and their tumor counterparts, the pheochromocytoma (PC12) cells, are well-established
model systems in neurobiology. The development of sympathoadrenal progenitor cells to chromaffin cells can be studied with
regard to developmental signals which trigger the differentiation. With regard to potential treatments of neurological disorders
like Parkinson’s disease chromaffin cell grafting can be used as one therapeutical approach. The beneficial effect of chromaffin
cell grafts is possibly not only related to the release of dopamine but may also be linked to the release of growth factors.
One of the growth factors that is synthesized by chromaffin and PC12 cells is basic fibroblast growth factor (FGF-2). The
experimental data available so far, are in agreement with different functional roles of FGF-2. This article summarizes the
putative physiological functions of FGF-2 in the adrenal medulla. Three differential functional roles of FGF-2 are discussed:
(1) as a differentiation factor for sympathoadrenal progenitor cells; (2) as a target-derived neurotrophic factor for preganglionic
sympathetic neurons which innervate adrenal medullary cells; (3) as an auto-/paracrine factor in the adrenal medulla.
Accepted: 21 August 1996 相似文献
60.
风湿性心脏病二尖瓣置换术中细胞因子水平的变化 总被引:1,自引:0,他引:1
目的测定风湿性心脏病二尖瓣置换术中细胞因子水平,了解它们的变化规律。方法 11例体外循环(CPB)下二尖瓣置换术患者,分别于术前,主动脉阻断前,主动脉阻断后5min,主动脉开放后10min、1h、2h、4h、24h测定白介素6(IL-6)、白介素8(IL-8)、白介素10(IL-10)以及肿瘤坏死因子(TNF)。结果IL-6、IL-8、IL-10水平在CPB开始后逐渐升高,在主动脉开放后2h左右达到高峰(P<0.01)。之后逐渐下降,到主动脉开放后24h已显著下降。TNF水平在CPB开始后逐渐升高,在主动脉开放后24h仍维持在很高的水平(P<0.01)。结论CPB下二尖瓣置换术中既有促炎因子水平的升高,又有抗炎因子的激活。 相似文献