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61.
In the peritoneal cavity of the adult rat mast cells at the four stages of progressive maturation (and corresponding increase of sulphation of granules) are best demonstrated in free peritoneal fluid. Of the 0.1-0.2x10(6) cells in the free fluid, 26% are at stage 1 of maturation (all granules are stained by Alcian blue). 24% at stage 2 (majority of granules are stained by Alcian blue, minority by safranin), 20% at stage 3 (majority of granules are safranin-positive), and 30% at stage 4 (all granules are safranin-positive). Peritoneal washings yield a mean of about 1.3-1.8x10(6) mast cells of which 16% are at stage 1, 24% at stage 2, 34% at stage 3 and 26% at stage 4. The greater number recovered by washing, compared with the number in free peritoneal fluid, suggests that a substantial number of mast cells lie on the surface of the peritoneal membranes.  相似文献   
62.
The patient presented with the typical features of Down syndrome: hypotonia, brachycephaly, flattened occiput, bilateral prominent medical epican-thic folds, flat nasal bridge, protruding tongue, low-set dysplastic ears, short broad hands, bilateral clinodactyly and simian crease. The karyotype of this child was originally reported as normal. High-resolution chromosomes revealed extra material on the long arm of chromosome 18. The mother's karyotype showed a reciprocal translocation between the long arm of 18 and the long arm of 21 at band q23 and q22.1, respectively. FISH performed separately with two different 21q cosmid probes gave two signals on the mother's metaphases and three signals on the prob-and. These findings confirmed that the proband is trisomic for the long arm of chromosome 21 at loci D21S65 and D21S19.  相似文献   
63.
利用PCR方法,从阴离子交换蛋白1(AE1)全长cDNA中扩增出约350bp c末端cDNA片段,测序后将其克隆至pGADT7载体上,用醋酸锂法构建好的pADT7-AE1-c末端转染酵母菌HA109,观察其在选择性培养基上的表达情况。结果表明,获得了530bp AE1c-末端cDNA,pGADT7-AE1-c末端对酵母无毒性,不能激活检测基因,可作为酵母双杂合系统中的靶基因。  相似文献   
64.
Helicobacter pylori (HP) infection induces expression of IL-8 and IL-10 in benign gastric epithelium. This study compared the expression of cytokines in CD4+ and CD8+ lymphocyte subsets of peripheral blood lymphocytes (PBL), benign mucosal lymphocytes (ML), and tumor infiltrative lymphocytes (TIL) as well as in the benign and malignant epithelial cells of the same patient, with respect to the presence of HP infection, lymph node metastases, and tumor histologic type. The mRNA of the cytokines was measured by a semiquantitative RT-PCR method. The levels were ranked and compared using the Wilcoxon sign-ranked test. Compared with CD8+ ML, the CD8+ TIL expresses higher levels of IL-6 and IL-8 but lower level of IL-4 in patients with lymph node metastases. In patients with HP infection, expression of IL-8 and IL-10 was higher in the gastric carcinoma cells than in the benign epithelial cells while expression of IL-6 and IL-8 were higher in CD8+ TIL than CD8+ ML. Overexpression of IL-8 in HP associated gastric carcinomas suggested that they might have arisen from HP-infected epithelial cells.  相似文献   
65.
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   
66.
目的 研究人外周血CD4^ /CD8^ T细胞4种神经营养素受体基因的转录。方法 应用尼龙手法分离出T细胞,磁式细胞分离法(MACS)分离CD4^ /CD8^ T细胞亚群,再以RT-PCR法研究4种神经营养素受体在两种T细胞亚群上的表达。结果 未经刺激的CD4^ /CD8^ T细胞亚群不表达任何神经营养素受体。经PHA或PPD刺激后,CD4^ /CD8^ T细胞亚群表达trkA,CD8^ T细胞亚群表达trkC;而在各种状态下的T细胞上均未见表达trkB及p75^NGFR。结论神经营养素受体在两种T细胞亚群中有不同的表达格局,提示不同T细胞亚群受神经营养素调节的模式可能各不相同。  相似文献   
67.
碱性成纤维细胞生长因子 (b FGF)是近年来研究较为广泛的生长因子之一 ,对骨组织有着广泛的生物学效应。本文就 b FGF的研究进展及其目前在骨组织工程学研究方面的应用做一综述  相似文献   
68.
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   
69.
金永柱  张庆殷  谢蜀生 《现代免疫学》2003,23(3):173-176,167
文章通过特异的引物分别扩增出CTLA 4和FasL胞外区的cDNA ,将它们拼接后 ,克隆入真核表达载体pcDNA3 1( + )中 ,进行表达、纯化 ,获得CTLA 4 FasL融合蛋白。Westernblot分析显示了该融合蛋白具有CTLA4 胞外区和FasL胞外区的抗原性。体外试验表明 ,该融合蛋白可以结合Jurkat细胞表面的Fas受体和Raji细胞表面的B7分子 ,表明了该分子双特异性的特点。该融合蛋白能够直接诱导Jurkat细胞发生凋亡 ,且此凋亡效应伴随Raji细胞的参与而增强 ,初步证实了该分子的免疫抑制效应 ,从而为进一步研究该融合蛋白特性及应用奠定了基础。  相似文献   
70.
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   
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