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31.
高效液相色谱法测定右旋儿茶素血浆浓度及药代动力学参数 总被引:1,自引:0,他引:1
本文建立了体液中右旋儿茶素的RP-HPLC测定方法。采用C_(18)键合相硅胶为填料的固相提取柱进行样品预处理,右旋儿茶素的提取回收率为79.8%.应用二极管阵列检测器对色谱峰纯度进行鉴定。该法精密度好,方法回收率近100%,日内、日间的变异系数为2.4~5.6%,血浓69.6~1160 ng/ml范围内呈线性关系,r=0.9993。家兔静注右旋儿茶素18mg/kg,其药代动力学过程符合二室模型,分布相半衰期为0.129 h,消除相半衰期为1.19h。 相似文献
32.
Chao-Long Chen Kuei-Liang Wang Yu-Ling Hui Wen-Bin Shieh 《Cancer chemotherapy and pharmacology》1992,31(Z1):S162-S165
Between March 1984 and February 1991, six orthotopic liver transplantations were performed at the Chang Gung Memorial Hospital in Taiwan. The indications for transplantation were Wilson's disease (5 patients) and biliary atresia (1 patient). Donors and recipients were matched only for size and ABO blood group compatibility, and the recipient operations were performed without the use of a venovenous bypass. Arterial reconstruction was carried out by end-to-end hepatic artery anastomosis (4), thoracic aortic conduit (1), or interposition of an iliac artery graft (1), whereas biliary reconstruction was accomplished by a choledochocholedochostomy using a T-tube stent (4) or a choledochocholedochostomy using an external cholecystostomy without stenting (2). Biliary complications occurred in three patients, and all required additional surgery. The average duration of donor-liver cold ischemia, operating time, and blood loss during surgery were 7 h and 50 min (range, 4.5–9 h), 13.5 h (range, 11.8–17h), and 4,385 ml (range, 750–12,000 ml) respectively. The immunosuppressive regimens included a cyclosporinsteroid combination (n=2) and a triple-drug combination (n=4). All except one of the surviving patients experienced at least one rejection episode that was reversed by a methyl-prednisolone bolus and/or recycle. One patient developed a primary cytomegalovirus (CMV) infection that responded well to Ganciclovir treatment. Two of the patients died, one of injuries sustained in a traffic accident 3 years after transplantation, and the other of massive upper gastrointestinal bleeding. The overall survival value at 3 months was 83%, and the follow-up period ranged from 3 months to 7 years. All of the survivors have achieved complete rehabilitation and currently enjoy an excellent quality of life with normal liver function. Althought the present study involved a small number of cases, our results indicate that liver transplantation can be successfully achieved in a high proportion of patients with acceptable morbidity, mortality, and cost in an Asian setting. The extreme shortage of donor organs is currently the most important obstacle limiting the application of liver transplantation in Taiwan.Presented at The Second International Symposium on Treatment of Liver Cancer. Taipei, 3–4 February 1991 相似文献
33.
采用毛细管流交仪测定了PBT/PC共混物的表观粘度、剪切应力,观察了不同共混物组成和不同温度下共混物的流变行为,并借助扫描电镜对共混物和微观形态结构进行分析。结果表明:PBT/PC熔体共混物的流变行为接近假塑性流体.温度对共混物的流变行为影响很大,共混物的熔体粘度在PBT/PC为90/10和60/40时呈双极值.共混物为两相结构,PC含量为4-50%时呈两互锁结构。 相似文献
34.
Human renin is synthesized as an inactive zymogen (prorenin) which is processed to the active form. We synthesized an 11-amino acid peptide which spans the human prorenin processing site in order to develop a simple assay to study human prorenin activation. Six enzymes which are capable of activating recombinant prorenin in vitro were studied. Four of these enzymes digested the synthetic peptide in a specific fashion, as analyzed by reverse-phase high-performance liquid chromatography. Amino acid analysis of the purified digestion products revealed that trypsin cleaves between Arg-Leu, the authentic processing site, while kallikrein, plasmin and elastase all cleaved at alternate sites. On the other hand, pepsin and cathepsin D did not cleave this substrate, suggesting that the activation of prorenin by these proteases might occur at a site distinct from the authentic processing site. Our data suggest that this synthetic peptide may be used as a simple and specific assay for prorenin activation. 相似文献
35.
Objective: To study the relationship between transaldolase activity, protein expression and testosterone synthesis in Leydig cells of pubertal mice. Methods: Leydig cells were cultured for 2 hours and 8 hours, to the Stimulation Group, hCG was added and to the Controls, only the vehicle. The testosterone concentration was then determined by enzyme-linked immunoadsordent assay (ELISA) and the transaldolase activity and protein expression by Western blot. Results: (1) Both the testosterone concentration and the transaldolase activity in both Stimulation Groups were significantly higher than those in the corresponding Controls (2 h: p<0.05-0.01; 8 h: P<0.001); (2) The ratios of the A isoform, the B isoform and the total transaldolase protein to β-actin between the Stimulation and Control Groups did not differ signifi-cantly. Conclusion: hCG stimulates the transaldolase activity as well as the testosterone synthesis in the Leydig cells of pubertal mice, indicating a positive relationship between them. 相似文献
36.
Sera from 130 first trimester pregnant women were tested for their serum antibody level against a naturally occurring serum antigen purified from non-pregnancy sera. IgG and IgM antibody level was measured using enzyme linked immunosorbant assay. Results indicate that patients with multiple abortion (n=26) have significantly (p=0.0029) lower level of IgG antibody and significantly (p=0.0001) higher level of IgM antibodies; against the serum antigen as compared to the patients with successful pregnancies with no history of miscarriage (n=63). Western blot analysis identified the scrum antigen recognized by the IgM antibody as a 24 kDa molecular mass component. These IgG and IgM antibodies may play an important role in the outcome of pregnancy. 相似文献
37.
38.
目的探讨脊髓运动诱发电位(SCMEP)在脊髓肿瘤手术中监测的应用价值.方法采用硬膜外电极在椎管内直接刺激脊髓记录脊髓运动诱发电位(SCMEP)监测脊髓肿瘤手术,并对17例肿瘤患者的手术监测的记录结果进行回顾性分析.结果SCMEP由于病变部位及性质、刺激电极与记录电极间的距离不同,波幅及潜伏期的差异较大,电极安放后与手术结束时的结果个体对照,相差不显著(P=0.083;P=0.387).7例术中波幅降低超过预警值20%,5例经短暂休息或改变手术方向后,波幅恢复正常.结论SCMEP的波幅变化是提示脊髓损伤的可靠性灵敏指标,对辅助医生进行手术安全操作,缩短手术时间,提高手术质量,减少术后神经功能障碍起到重要作用. 相似文献
39.
40.
目的 克隆人野生型parkin基因并构建真核表达载体pCDNA3.1—parkin,将重组质粒转染PC12细胞获得高表达人野生型parkin基因的PC12细胞克隆。方法 从胎脑组织中提取总RNA,用RT—PCR方法获得人野生型parkin基因的全长cDNA,插入pCR2.1—TA克隆载体中进行序列测定,测序正确后将其亚克隆至表达载体pCD—NA3.1,利用脂质体将重组质粒转染PC12细胞,经G418筛选获得抗性细胞克隆,采用RT—PCR和Western Blot方法鉴定人野生型parkin基因在PC12细胞中的过表达。结果 经限制性内切酶酶切图谱分析和DNA序列测定证实目的基因已插入重组质粒,RT—PCR和Western Blot证明经G418筛选得到的转基因PC12细胞克隆中存在人野生型parkin基因的表达。结论 成功构建了人野生型parkin基因的真核表达载体,获得了稳定表达人野生型parkin基因的PC12细胞克隆,为进一步研究parkin的生物学功能以及parkin在帕金森病发病机制中的作用奠定了良好的基础。 相似文献