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51.
Antibody against fusarochromanone (TDP‐1) was obtained from rabbits after immunization with TDP‐1 conjugated to bovine serum albumin (BSA). An indirect enzyme‐linked immunosorbent assay (ELISA) using TDP‐1‐ovalbumin conjugate as the antigen coated on to the microtiter plate was used for monitoring the antibody liter. For toxin detection, a direct competitive ELISA in which TDP‐1 was conjugated to horseradish peroxidase (HRP) was used. Competitive direct ELISA revealed that the antibody had about 5.6 and 4.5 times greater binding efficiency for monoacetyl fusarochromanone (TDP‐2) and diacetylated TDP‐1 than TDP‐1. The concentration causing 50% inhibition of binding of TDP‐1‐HRP to the antibody by TDP‐1, TDP‐2 and diacetyl‐TDP‐1 were 2.8, 0.5 and 0.62 ng/ml, respectively. For the analysis of fusarochromanones in wheat and barley, the toxins were first extracted from the commodities with 100% methanol. A small aliquot of the extract was dried, acetylated, diluted in buffer and then analyzed directly by ELISA. The overall recovery for fusarochromanone in the wheat and barley samples spiked with TDP‐1 in the concentration range of 20 to 500 ppb were found to be 97% and 103.4% with cv of 15% and 11.2% for barley and wheat, respectively. 相似文献
52.
Fahao Zhang Juwon Lee Daren Wang Zhongyun Dong 《Journal of interferon & cytokine research》2006,26(2):108-118
The purpose of this study was to investigate the therapeutic potential of interferon-beta (IFN-beta) against tumors that resist its antiproliferative effects. Mouse fibrosarcoma cells (UV-2237m-P) and their counterparts, transfected with either IFN-beta cDNA (UV-2237m-IFN-beta) or its control vector (UV-2237m-neo), were used in the study. UV-2237m-IFN-beta cells, still expressing functional IFN receptors, were resistant to the antiproliferative effects of IFN-beta. UV-2237m-P and UV-2237m-neo cells produced progressive tumors in both nude and IFN receptor-null nude (IFNAR-/-nude) mice. In contrast, growth of UV-2237m-IFN-beta cells was significantly delayed in nude mice. UV-2237m-IFN-beta tumors from nude mice contained fewer microvessels, fewer proliferating cells, and more apoptotic cells than did UV-2237m-P and UV-2237m-neo tumors. They expressed high levels of inducible nitric oxide synthase (iNOS) and were densely infiltrated by macrophages. Incubation with macrophages from nude mice, but not those from IFNAR-/- nude mice or iNOS-null/nude mice, led to more significant killing of UV-2237m-IFN-beta cells than that of control cells, which was blocked by iNOS inhibitor N-methylarginine. Similarly, more UV-2237m-IFN-beta cells were killed when they were incubated with spleen lymphocytes from nude mice. These data indicate that IFN-beta can inhibit growth of IFN-beta-resistant tumors by T cell-independent host-mediated mechanisms, including the role of macrophages, natural killer (NK) cells, and iNOS activity. 相似文献
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R. B. gilbertsen K. M. Cullinen D. J. Wilburn M. K. Dong M. C. Conroy 《Inflammation research》1989,27(3-4):303-305
CI-949 (5-methoxy-3-(1-methylethoxy)-1-phenyl-N-1H-tetrazol-5-yl-1H-indole-2-carboxamide,l-arginine salt), an antiallergy compound was found to be a weak inhibitor of IL-1 release from LPS-stimulated murine peritoneal exudate cells and human peripheral blood leukocytes, with IC50s of 186.2 and 267.9 M, respectively. CI-949 was also a poor inhibitor of release of IL-2 from Con A-stimulated rat spelenocytes (37% inhibition at 100 M). CI-949 did produce concentration-related inhibition of the response of human lymphocytes to PHA and Con A (IC50s=44.7 and 21.5 M, respectively) as well as in the mixed lymphocyte reaction (MLR) (IC50=16.8 M). The clinical significance of these latter findings is unknown at present. 相似文献
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目的 探讨二维超声对原发性肾病综合征预后的判断价值。方法 根据临床检查结果将 12 0例原发性肾病综合征患者分为 3组 ,并与二维超声检查结果进行相关性分析。结果 完全缓解组的肾脏超声检查结果与对照组比较无显著性差异 (P >0 .0 5 ) ,部分缓解组的肾脏超声检查结果与对照组比较有显著性差异 (P <0 .0 5 ) ,无效组的肾脏超声检查结果与对照组比较有非常显著性差异 (P <0 .0 1)。结论 二维超声检查原发性肾病综合征患者的肾脏无异常时预后良好 ,而肾脏缩小越明显 ,肾皮质回声越强 ,则预后越差。 相似文献
59.
目的 :研究肾综合征出血热 (HFRS)多尿期肾图的变化及其意义。方法 :静脉注射 1 31 I-邻碘马尿酸钠 (1 31 I- OIH) 3.7×10 9Bq(10 μCi) ,用闪烁照相法描记 15 min,通过电子计算机自动处理 ,得出肾图的各项参数。结果 :2 0例受检者均已进入多尿期 ,2 4h尿量在 2 0 0 0 ml以上 ,血尿素氮 (BUN)已正常或接近正常 ,但肾图却明显异常 ,表现为半排时间 (TC1 /2 )延长 (>8min) ,15min残留率 (C1 5 /b)超过 5 0 % ,肾脏指数大多低于 45 % ;同期作尿β2 -微球蛋白 (β2 - m )测定 ,也明显高于正常 ;8例作发射型电子计算机扫描 (ECT)检查 ,肾小球滤过率 (GFR)和有效肾血浆流量 (ERPF)分别为 (4 0 .8± 2 1.2 ) ml/min和 (35 0 .8± 10 2 .1) ml/min,均明显低于正常 (P<0 .0 1)。结论 :HFRS患者多尿期肾图大多呈排出不良和功能受损的图形 ,表明该期肾功能以及肾血流量尚未恢复正常 ,对症治疗仍需继续。 相似文献
60.
药用辅料在制剂中的应用概述 总被引:1,自引:0,他引:1
药用辅料是药物制剂的基础材料的重要的组成部分,在制剂型和生产中起着关键作用,它不仅赋予药物一定剂型,并且与提高药物的疗效,降低毒副作用有很大的关系,因此,研究开发,合理应用辅仅可提高药物制剂质量和生产技术水平,而且可取得较大的社会及经济效益。 相似文献