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91.
将PCR扩增的HTV76-118RNA小片段的cDNA克隆插入到载体pDS56/RBSⅡ-(O)-6His中,通过IPTG诱导表达以及镍螯合层析纯化重组NP,经过SDS-PAGE、免疫转印和ELISA方法分析其蛋白特性,证实该重组NP与毒粒NP相同,均为49.6ku,能与肾综合征出血热(HFRS)患者血清产生特异性反应。以此重组NP作为抗原制备抗NP单克隆抗体,获得两株持续稳定分泌单克隆抗体的杂交瘤细胞株。用抗NPMcAb建立检测IgM抗体的ELISA捕获法。证实纯化重组NP作为抗原,避免了组织培养病毒的感染性和非特异性以及难以标准化的缺点。所建立的ELISA捕获法检测HFRS患者血清中IgM抗体的方法特异性强、敏感性高,可作为HFRS的早期诊断试剂 相似文献
92.
用PCR体外定点突变技术诱导霍乱毒素A亚基突变体的构建 总被引:1,自引:0,他引:1
目的: 有效去除霍乱毒素A 亚基( CT A) 的毒性作用而保存其佐剂性能。方法: 采用PCR 体外定点突变技术(PCR SDM) ,设计两对引物,引入一个突变位点,通过重叠延伸法两次PCR 扩增,使CT A 编码基因第63 位密码子由CTC 突变为TTT,亦将扩增片断克隆入PUC19 载体。结果: DNA 测序结果表明在预期位点已发生突变,用PCR 诱导成功CT A 突变体。结论: PCR 诱导突变准确、简便,为深入研究CT 免疫佐剂的作用打下了基础 相似文献
93.
用LDH释放法判断细胞病变程度确定干扰素生物活性 总被引:2,自引:0,他引:2
目的:应用LDH释放法测定干扰素生物活性。方法:通过检测WISH细胞裂解后释放出的LDH活性判断细胞病变的程度,确定干扰素效价。对LDH释放法进行改进,与结晶紫染色法和MTT比色法进行灵敏度、重复性和相关性比较。结果和结论:该法减少了实验步骤和时间,成本低,敏感性高,重复性好,与其他方法所测结果无显著差异,简便实用,优于结晶紫染色法和MTT比色法。 相似文献
94.
Klinge U Zheng H Si Z Schumpelick V Bhardwaj RS Muys L Klosterhalfen B 《European surgical research. Europ?ische chirurgische Forschung. Recherches chirurgicales européennes》1999,31(6):480-490
Although abnormal collagen metabolism has been ascribed an important role in the high recurrence rates after surgical hernia repair, knowledge on tissue sampled in the region affected by inguinal hernias is poor. In the present study, we determined collagen type I and type III in the skin of adult patients with indirect and direct inguinal hernias by both immunohistochemistry and Western blot analysis. In addition, we quantified the immunohistochemical expression of fibronectin and matrix metalloproteinase (MMP)-1 and -13. The results indicated that the ratio of collagen type I/III was significantly decreased in the skin of patients with either indirect (n = 9) or direct hernia (n = 7), with a concomitant increase in collagen type III (p < 0.001 vs. controls, n = 7, without affection of the inguinal region). There was no significant difference between patients with indirect and direct hernia (p > 0.05). MMP-13 was not expressed in any of the skin samples investigated, whereas MMP-1 was found in the epidermis. Fibronectin was predominantly detected at the epidermal-dermal junction. MMP-1, MMP-13 and fibronectin levels were significantly different between patients and controls (p > 0. 05). We conclude that in contrast to the unchanged expression of fibronectin and MMP-1 and MMP-13, the decreased ratios of collagen tpye I/III with the basically increased amount of collagen type III could be of significant importance for the pathophysiology of hernias. The specific ratio collagen I/III probably reflects the altered structural integrity and mechanical stability of the connective tissue in both indirect and direct hernias. Moreover, our findings stress that hernias should be regarded as the manifestation of a systemic disease in the inguinal region with a genetic background, explaining the high recurrence rates after repeated suture repair, as well as the usefulness of surgical meshes in this clinical setting. 相似文献
95.
Klinge U Zheng H Si ZY Schumpelick V Bhardwaj R Klosterhalfen B 《International journal of surgical investigation》1999,1(3):219-227
Since many years the importance of a weakness of the soft tissue for the development of hernias is discussed controversially. The tensile strength of the tissue is supposed to depend largely on the varying proportion of type I collagen with its high tensile strength and the immature type III collagen. Their relation is regulated by several collagenases, mainly matrix metalloproteinases-1 and -13 (MMP-1 and MMP-13), whereas fibronectin plays a key role for the adherence of cells within the extracellular matrix. The aim of this study was to investigate whether an alteration in type I and type III collagen synthesis, amounts of MMP-1 and MMP-13 and the expression of fibronectin were associated with the development of inguinal hernia. We analysed the hernial sac of patients with indirect (n = 9) and direct (n = 7) inguinal hernias and peritoneum in controls (n = 7) by immunohistochemistry and Western blot analysis. The results showed that the ratio of relative amount of I/III collagen was markedly decreased in patients with either indirect or direct hernias as compared with controls (p < 0.001) with a concomitant increase in type III collagen synthesis. MMP-13 was expressed neither in the hernial sac nor in the peritoneum of the controls, but the positive reactions of MMP-1 were found in the surface of the subserosa of the hernial sac in patients with indirect or direct hernias without any difference compared to controls. Furthermore, the relative amount of fibronectin in patients with either indirect or direct hernias is not significantly different from controls (p > 0.05). In regard to the known alterations of the collagen metabolism in fascia and skin of hernia patients the changed collagen I/III ratio with its increase of type III collagen in hernial sacs support the presence of a systemic disturbance of collagen metabolism. The absence of changes of the expression of collagenases (MMP-1, MMP-13) and the constant levels of fibronectin underline the central role of collagen synthesis for the development of indirect or direct hernias. 相似文献
96.
97.
98.
目的:为了解空勤与地勤人员的硒摄入,吸收和排泄量,以及硒代谢的差异,进一步做好空勤与地勤人员的营养保障,方法:用双盘法在3d自由进食条件下对36名空勤人员进行了硒代谢平衡的研究,并以36名地勤人员作为对照,结果:空勤组的硒摄入量(59.85μg.d^-1)尿硒排泄量(30.84μg.d^-1),表现吸收量(39.27μg.d^-1)和全血硒(98.91ng.ml^-1)均高于地勤组(45.96μg 相似文献
99.
Beauveria sp. FO-6979, a soil isolate, was found to produce inhibitors of lipid droplet formation in mouse peritoneal macrophages. A new compound beauveriolide III was isolated along with a known compound beauveriolide I from the fermentation broth of the producing strain by solvent extraction, ODS column chromatography, silica gel column chromatography and preparative HPLC. Beauveriolides I and III caused a reduction in the number and size of cytosolic lipid droplets in macrophages at 10 microM without any cytotoxic effect on macrophages. 相似文献
100.
目的 重点讨论手术方式对老年性胃癌根治术预后的关系。 方法 回顾分析 1995年 1月~2 0 0 0年 1月共收治的 83例 6 5岁以上老年性胃癌根治术随访 3年 ,分析手术方式和心肺合并症的关系及其对死亡的影响。 结果 三年后U区癌心肺合并症死亡 2 6例 (2 6 / 83,31 1% ) ,M区癌心肺合并症死亡 2例 (2 / 83,2 4 % ) ,L区癌心肺合并症死亡 8例 (8/ 83,9 6 % ) ,M区和L区共计 10例 (10 / 83,12 % )。两组 (U区与M +L区 )死亡率相比有显著差异 ,P <0 0 1。 结论 U区开胸手术易引起心肺合并症 ,是老年性胃癌根治术后死亡率增高的主要原因。 相似文献