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91.
目的 了解脐带血T细胞及其CD4 和CD8 T细胞亚群的信号传导分子CD3ζ基因的表达特点.方法 采用SYBR Green Ⅰ荧光定量PCR和相对定量分析法检测60例脐带血单个核细胞和12例纯化脐带血CD4 及CD8 T细胞的CD3ζ基因的表达情况,以β2微球蛋白基因(β2M)作为内参,采用相对定量公式:2-△Ct×100%,计算CD3ζ基因相对mRNA表达量,60例健康成人作为对照.并根据荧光定量PCR熔解曲线特点和序列分析了解CD3ζ基因突变情况.结果 全部脐带血和健康成人外周血单个核细胞均表达CD3ζ基因,不同个体CD3ζ基因表达量有所差异,脐带血T细胞CD3ζ基因相对mRNA表达量为6.7%±5.56%,CD4 和CD8 T细胞的CD3ζ基因相对mRNA表达量分别为6.74%±2.0%和6.88%±1.76%,三者CD3ζ基因表达量均明显高于健康成人(P=0.000,P=0.034,P=0.000).序列分析结果显示尚未发现国外文献所报道的ζ链剪接异构体.结论 本研究率先报道了脐带血T细胞及其CD4 和CD8 T细胞亚群的CD3ζ基因mRNA的表达水平,为进一步了解脐带血T细胞免疫学特点提供新的基础资料.  相似文献   
92.
Objective:To investigate the feasibility of a 4D-CT reconstruction method based on the similarity principle of spatial adjacent images and mutual information measure. Methods:A motor driven sinusoidal motion platform made in house was used to create one-dimensional periodical motion that was along the longitudinal axis of the CT couch. The amplitude of sinusoidal motion was set to an amplitude of ±1 cm. The period of the motion was adjustable and set to 3.5 s. Phantom objects of two eggs were placed in a Styrofoam block, which in turn were placed on the motion platform. These objects were used to simulate volumes of interest Undergoing ideal periodic motion. CT data of static phantom were acquired using a multi-slice general electric (GE) LightSpeed 16-slice CT scanner in an axial mode. And the CT data of periodical motion phantom were acquired in an axial and cine-mode scan. A software program was developed by using VC + + and VTK software tools to resort the CT data and reconstruct the 4D-CT. Then all of the CT data with same phase were sorted by the program into the same series based on the similarity principle of spatial adjacent images and mutual information measure among them, and 3D reconstruction of different phase CT data were completed by using the software. Results:All of the CT data were sorted accurately into different series based on the similarity principle of spatial adjacent images and mutual information measures among them. Compared with the unsorted CT data, the motion artifacts in the 3 D reconstruction of sorted CT data were re- duced significantly, and all of the sorted CT series result in a 4D-CT that reflected the characteristic of the periodical motion phantom. Conclusion:Time-resolved 4D-CT reconstruction can be implemented with any general multi-slice CT scanners based on the similarity principle of spatial adjacent images and mutual information measure. The process of the 4D-CT data acquisition and reconstruction were not restricted to the hardware or software of the C  相似文献   
93.
Objective To investigate the effect of recombinant human granulocyte macrophage colony stimulating factor (rhGM-CSF) as adjuvant on immune response in adults of non-and hyporesponders to hepatitis B vaccine. Methods Those who were once immunized with recombined yeast gene hepatitis B vaccine more than one standard scheme in two years and negative for hepatitis B markers were randomly sorted as group A and group B. 33 adults of group A were given hepatitis B vaccine 10 μg each time. The immune procedure was O, 1 and 6month. 34 adults of group B were given rhGM-CSF 300 μg for the first day, then 10 μg each time for routine immune. The blood samples were collected before the first injection and in 1, 2 and 8 months (T1, T2, TS)following the first injection to test Anti-HBs. Results Anti-HBs positive conversion rates of group A and B at T8 was 39.39% and 64.71% respectively(P=0.038). Anti-HBs levels of group B at TI, T2, T8 were(113.85±198.56) mIU/ml, (312.40±349.44) mIU/ml, (427.74±411. 58) mIU/ml (P=0.001). There was significant difference between group A and B in T8 Anti-HBs levels(P=0.010). Conclusion Better immune response was found in the group of rhGM-CSF with hepatitis B vaccine. So rhGM-CSF can induce the immune respond to hepatitis B vaccine.  相似文献   
94.
三氧化二锑诱导急性早幼粒细胞白血病细胞凋亡的研究   总被引:2,自引:0,他引:2  
目的 研究锑剂三氧化二锑(Sb2O3)对早幼粒细胞白血病细胞株NB4凋亡的诱导作用,以寻求早幼粒细胞白血病治疗的新方法。方法 采用细胞生长曲线,形态学及硝基四氮唑蓝(NBT)还原试验,判定NB4细胞的生长,分化及功能。采用细胞周期分析和DNA电泳研究细胞凋亡。结果 Sb2O3能诱导早幼粒白血病细胞凋亡,且具有时间,剂量依赖性。结论 Sb2O3能有效地诱导早幼粒白血病细胞凋亡,提示锑剂诱导细胞半亡的疗法,有望成为临床治疗早幼粒细胞白血病的新方法。  相似文献   
95.
患者女,66岁.以左上腹闷痛半年,发现左腹肿块3个月,于2007年8月16日入本院治疗.既往无特殊病史;入院体检:痛苦面容,营养尚可,全身浅表淋巴结未及肿大,心肺正常,左上腹稍膨隆,触及一约10 cm×12 cm的包块,质中、表面光滑、界欠清、活动度差、轻压痛,左肾下极下移、轻压痛.  相似文献   
96.
Objective To evaluate the effect on myocardial protection of adenosine preconditioning in different route of administration through right jugular vein and left ventricle.Methods 48 SD rats were randomly divided into ischemia reperfusion group(blank control),ischemic preconditioning group(IP,positive control),adenosine venous infusion group,adenosine in ventricular group,normal saline(NS)venous infusion group(negative control I)and NS in ventricular group(negative control Ⅱ).The ischemia reperfusion rats model were established in vivo,and then changes of heart function,serum cardiac troponin T (cTnT),superoxide dismutase(SOD),malondialdehyde(MDA)and expression of nuclear factor KB(NF-kB) were observed.Results SOD in IP[(208.63±23.88)U/ml],adenosine venous infusion group [(178.27±11.56) U/ml]and adenosine in ventricular group[(191.31±28.14)U/ml]were significantly higher than that in the ischemia reperfusion group[(145.05±23.18)U/ml](P<0.05),cTnT,MDA and expression of NF-kB were lower than that in the ischemia reperfusion group (P<0.05).Heart function was significantly better than that in the ischemia reperfusion group(P<0.05);SOD in adenosine in ventricular group was significantly higher than that in adenosine venous infusion group(P<0.05).cTnT,MDA and expression of NF-kB were lower than that in adenosine venous infusion group (P<0.05).Conclusion Adenosine preconditioning may mimic protective effect of ischemic preconditioning. The effect on myocardial protection of adenosine in ventricular group was better than that of adenosine venous infusion group.  相似文献   
97.
目的从基因水平调查了中国华南、华北地区人群HLA-DQB1等位基因频率,并研究比较两地区人群HLA-DQB1多态性分布。方法采用深圳益生堂生物企业有限公司研制开发的“HLA-DQB1低分辨率分型基因芯片检测试剂盒”,应用聚合酶链反应.序列特异性引物+序列特异性寡核苷酸探针芯片检测技术,对700名南方地区的中国人和320名北方地区的中国人进行基因分型。结果鉴定了10个HLA-DQB1等位基因,获得了一组准确、科学的统计数据。结论得到了中国华南、华北地区人群HLA-DQB1等位基因频率差异的数据,证明中国人群HLA-DQB1*02,05,0601,0602,0603的分布南北差异有统计学意义(P〈0.05),为疾病相关性研究、人文科学研究提供了可靠的遗传学数据。  相似文献   
98.
DRB1*08 haplotypes have not been known to carry a DRB3 gene. We have found a patient suffering from liver disease who has a novel HLA haplotype of DRB1*0801 with DRB3*0202 as established by family segregation. These two genes were confirmed by sequencing. DR8 and DR52 antigen specificities were serologically detected, indicating expression of these genes.  相似文献   
99.
TRP(Transient receptor potentical)家族是非选择性阳离子通道家族,近来发现其与肾脏关系密切,如调节肾小管离子转运,肾脏微循环等。TRP通道异常可导致遗传性局灶节段硬化性肾病(FSGS),常染色体显性遗传多囊肾(ADPKD),低镁血症继发低钙血症(HSH)等,对TRP通道的进一步研究将有助于临床肾脏病的防治。  相似文献   
100.
甲型血友病是最常见的遗传性出血性疾病,受到了国内外研究者们的极大关注.由于此病尚无彻底根治方法,所以基因诊断及产前诊断显得尤为重要.基因诊断可分为直接基因诊断及间接连锁分析的方法;产前诊断的手段也在近年飞速发展.本文就直接基因诊断、间接连锁分析及产前诊断新技术这几方面的研究进展综述如下.  相似文献   
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