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31.
Neutrophil oxidative metabolism, C3d and beta 2 microglobulin levels, were assessed in nine consecutive patients undergoing cardiopulmonary bypass surgery with polypropylene hollow fiber oxygenators for open cardiac operations. Generation of oxygen free radicals by neutrophils was measured as luminol-enhanced chemiluminescence after stimulation with opsonized Zymosan and phorbol myristate acetate. A significant increase in light emission was detected by using both of the chemiluminescence stimulators. Moreover, a remarkable and significant increase in C3d levels was found already at 10 min. Conversely minimal changes in levels of beta 2 microglobulin were detected during cardiopulmonary bypass surgery. These data suggest that the impact of the patient blood with the foreign surface of cardiopulmonary bypass results in activation of phagocyte cells with increased potential in oxygen consumption. These effects could be partially complement-mediated.  相似文献   
32.
本文采用层析法进行鉴定,用氨基酸分析仪测氨基酸的含量,为胎盘组织液的质量标准提供可靠依据。本法准确率为99%。  相似文献   
33.
Background Exposure of the skin or respiratory tract to proteinases is frequently associated with allergic sensitization. This is of particular significance in the domestic indoor environment where the proteolytic activity of Der p I, the group I allergen of the house dust mite Dermatophagoides pteronyssinus, may influence the allergenicity of mites. Using class-specific proteinase inhibitors and active-site affinity chromatography, we have previously shown that Der p I exhibits a mixed cysteine-serine proteinase activity. Measurement of the amount of cleavage, however, did not determine whether the inhibitors used were targeting exactly the same proteolytic mechanism. Objective To resolve this issue, we have examined whether the cleavage specificity of the cysteine and serine proteinase activities of Der p I was the same. Methods HPLC and mass spectrometry were used to analyse and identify the products of a Der p I-digested peptide substrate and thus identify the peptide bonds cleaved. Results Der p I cleaves different peptide bonds, depending upon the class of proteolytic mechanism used. In the model peptide substrate insulin B chain, the cysteine and serine proteinase activities of Der p I showed preference for glutamic acid and arginine respectively in the P1 position. Conclusion These data suggest the existence of more than one mechanistic form of the allergen immunologically identified as Der p I. If proteolytic activity is indeed a function of allergenicity, this information may have important implications for the pathogenicity of Der p I and the ability of innate antiproteinase defences in the respiratory tract to prevent immune sensitization.  相似文献   
34.
35.
Background: Fluctuations in the level of mite allergens in domestic house dust are the result of changes in the balance between synthesis, removal and decay. Purely physical forces as well as enzymatic degradation, mediated by house dust inhabiting microbes, may contribute to the decay of allergens in domestic dust. Knowledge about the speed of decay is essential for an understanding of the dynamics of allergen levels. Objective: The present study is a quantitative assessment of the speed of decay at nine combinations of temperature (15°C, 20°C and 25°C) and relative humidity (33%, 55% and 75%). Methods: Samples of mite infested material of an old rug were stored at these temperature/relative humidity-combinations for 6, 12 or 18 months, after the mites were killed by cither a freezing treatment or an acaricide (lindane). The microbes living in the rug presumably survive these treatments. Concentrations of Der p I and Der p II + Der f II. in extracts of the rug material, were measured by a radio immunoassay. Results: No significant changes in the levels of Der p I and Der p II +Der f II, could be detected even after 1p>1p>/2 year at a high temperature and humidity. Conclusion: These findings incidate that mite allergens can be extremely stable under normal domestic circumstances.  相似文献   
36.
We performed an immunohistochemical analysis to investigate the expression of p53 protein in a panel of 18 laryngeal squamous cell carcinomas, 15 primary tumours and three in relapse, previously analysed by us for the presence of p53 gene mutations. Dysplastic and/or normal surrounding mucosa was evaluated in 15 different tumours. The results of our study are the following: (1) expression of p53 protein was observed in one out of five tumours positive for p53 gene mutations (20%) and in 10 out of 13 (80%) negative cases; (2), p53 protein over-expression was frequently observed in normal and/or dysplastic mucosa surrounding either wild-type (7/11) or mutated p53 tumours (2/4); (3), p53 immunoreactive cells showed a pattern of distribution in normal and mildly/moderately dysplastic mucosa (basal layers), different from that in severely dysplastic mucosa (whole thickness). These data further support the hypothesis that p53 protein over-expression may be a marker of the earliest phases of multistep tumorigenesis in laryngeal squamous cell carcinoma.  相似文献   
37.
P16、Cyclin D1蛋白表达与胰腺癌生物学行为   总被引:2,自引:2,他引:0  
目的 探讨P16、CyclinD1蛋白表达水平与胰腺癌发生、发展及预后的关系。方法 应用免疫组织化学SP法结合微波抗原修复法对53例原发性胰腺癌和42例胰腺良性病变及正常组织中P16蛋白及CyclinD1蛋白进行检测。结果 胰腺癌组织、胰腺良性病变和正常组织中P16蛋白的阳性率分别为66.04%和87.71%(P<0.05);CyclinD1表达的阳性率分别为52.83%和23.81%(P<0.05),P16及CyclinD1蛋白表达与胰腺癌的组织分化、病理分期及术后生存期密切相关。结论 P16及CyclinD1蛋白在胰腺癌中的表达可判断胰腺癌的预后。  相似文献   
38.
毛喉萜对人肝癌细胞增殖影响的实验研究   总被引:1,自引:0,他引:1  
目的 探讨毛喉萜 (Forskolin)的抗肝癌作用。方法 采用克隆形成、MTT比色法观察毛喉萜对SMMC 772 1细胞的作用 ,并利用免疫细胞化学方法检测其对rasp2 1、p5 3蛋白表达的影响。结果 毛喉萜可明显抑制SMMC 772 1细胞的增殖 ,其抑制率与剂量呈正相关 (P <0 .0 1 ) ,经毛喉萜处理后 ,rasp2 1、p5 3蛋白表达均有明显下降。结论 毛喉萜能明显抑制肝癌SMMC 772 1细胞增殖 ,其作用可能与降低rasp2 1、p5 3蛋白表达有关。  相似文献   
39.
目的探讨不同剂量γ射线照射后诱导脂质体介导的p16基因在HeLa细胞中的表达及抗癌作用。方法用脂质体Lipofectamin介导重组质粒Egr-p16转染人HeLa细胞,采用RT-PCR的方法检测了。Coγ射线照射转染后的人HeLa细胞剂量效应和时程变化,用细胞计数检测细胞增殖的变化,用流式细胞术检测细胞周期的变化。结果研究证实0.5~8Gv照射后p16的转录水平高于对照,在2~4Gy照射后达到峰值,2Gy照射后2—24h高于对照组,在照射后4h达到峰值,然后逐渐下降。细胞生长曲线显示体外稳定转染联合。Coγ射线照射对HeLa细胞的增殖具有明显的抑制作用。细胞周期变化显示转染后的HeLa细胞经过照射后G0/G1期比例呈现剂量依赖性的下降,而S期则出现剂量依赖性的增加,出现明显的S期阻滞,G2/M期在2Gy出现明显的阻滞,在5和10Gy时逐渐下降,但是仍然高于对照组。结论^60Coγ射线可诱导转染的HeLa细胞p16转录水平的增强,同时在细胞增殖上出现明显的变化。  相似文献   
40.
目的:探讨外源性p21^WAF1/CIP1基因对胶质瘤细胞生长和细胞周期的影响.方法:采用脂质体介导法将p21^WAF1/CIP1基因质粒转导人人胶质瘤细胞系SHG44细胞,然后用电镜、流式细胞仪等技术对细胞形态、生长及细胞周期进行观察。结果:酶切电泳和斑点杂交显示p21^WAF1/CIP1基因成功的转染至SHG44细胞。转染p21^WAF1/CIP1基因的细胞光镜及电镜下可见凋亡产生;生长速度明显慢于亲代细胞,其倍增时间约是对照细胞的二倍;细胞周期发生明显改变,G1期明显增多,S期明显减少.结论:外源性p21^WAF1/CIP1基因对SHG44细胞的生长和细胞周期有明显的抑制作用,并可诱导细胞凋亡产生。  相似文献   
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