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101.
目的:探讨幽门螺杆菌(Hp)阳性十二指肠球部溃疡患者红细胞免疫功能的变化。方法:47例Hp阳性十二指肠球部溃疡和32例健康体检者入选,前者以标准方案治疗7d,后者不予处理作为对照。治疗前后分别以流式细胞仪测定其血液红细胞上CR1的数量,以免疫粘附酵母菌花环法测定其活性。结果:与正常人相比,Hp阳性十二指球部溃疡红细胞C3b受体花环率、红细胞CR1数量降低(P<0.01),红细胞免疫复合物花环率增高(P<0.01)。结论:Hp的感染可能是导致十二指肠球部溃疡患者红细胞免疫功能低下的原因。 相似文献
102.
103.
茄根酸性组分对脂多糖诱导的小鼠腹腔巨噬细胞核因子kB表达的影响 总被引:1,自引:1,他引:1
目的:探讨茄根酸性组分的抗炎机理。方法:以淀粉诱导小鼠腹腔巨噬细胞,用LPS为刺激剂。诱导NF-kB的表达,再用NF-kB P65的抗体与其结合,用流式细胞术测定巨噬细胞表面NF-kB P65亚单位表达的荧光强度,反映NF-kB活化程度。结果:LPS刺激12h后,NF-kB P65的表达明显增加,茄根酸性组分能显著抑制NF-kB的表达(P〈0.01)。结论:抑制NF-kB的活化,可能是茄根酸性组分发挥抗炎作用的主要机理之一。 相似文献
104.
质疑血清药理学,加强多层次半体内实验研究 总被引:17,自引:1,他引:17
质疑血清药理学的主要理由包括①从胃肠吸收的中药成分在体内是进入血浆,而不是血清;②凝血过程有一系列酶生成,同时刺激白细胞释放溶酶,这些酶可能降解某些中药成分;③凝血酶刺激血小板与白细胞释放大量生物活性物质;④凝血过程伴有纤溶、补体、激肽等系统活化;⑤制备与灭活血清过程会导致中药成分与中药介导体内释放物质损失。新近利用HPLCMS指纹图谱分析与抗白血病细胞增殖实验证明利用血清药理方法可能带来错误结论。建议加强中药多层次半体内实验研究,其中血浆药理方法可能避免血清药理方法的弊病。 相似文献
105.
目的探讨异黄酮活性成分对β淀粉样蛋白(Aβ1-42)诱导的PC12细胞损伤的保护作用。方法从大豆中提取纯化异黄酮活性成分,以Aβ1-42诱导PC12细胞损伤为细胞模型,采用细胞形态学方法、MTT法、LDH法观察不同剂量的异黄酮活性成分对PC12细胞损伤的保护作用。结果异黄酮活性成分能有效地改善PC12细胞的形态,提高细胞存活率(P<0.05),保护组LDH活性低于损伤组(P<0.05)。结论大豆异黄酮活性成分对Aβ1-42诱导的PC12细胞损伤具有显著的保护作用。 相似文献
106.
Alexey V. Osipov Vladislav G. Starkov Elena V. Ryumina Leonid V. Kozlov Yvon Doljansky Yuri N. Utkin 《Toxicon》2005,46(4):394-403
Two forms of complement-depleting cobra venom factor (CVFm1 and CVFm2), possessing molecular masses of 142.6 kDa (CVFm1) and 143.1 kDa (CVFm2), according to MALDI mass-spectrometry, were isolated from the Naja melanoleuca cobra venom. As shown by polyacrylamide gel electrophoresis in the presence of SDS, both forms similarly to factor from the Naja kaouthia cobra venom (CVFk) consist of three polypeptide chains with molecular masses of about 70, 50, and 30 kDa, the two large subunits being glycosylated. As determined by MALDI mass-spectrometry, 30 kDa subunits of CVFm1 and CVFm2 have considerably different finger-prints of tryptic digests that suggests differences in their amino acid sequences. A study of activity in vivo has shown no significant differences in C3 consumption by CVFm1, CVFm2 and CVFk in mouse blood. However, as shown by an immunoassay method, they differ in their ability to activate the complement system via C3 conversion, the ratio of these activities for CVFm1:CVFm2:CVFk being 2.5:1.6:1. Kinetic studies using a hemolytic test showed that complement depletion by CVFm1 is faster than that by CVFm2. Thus, for the first time the presence in a single venom of two forms of CVF differing by both amino acid sequence and biological activity has been shown. 相似文献
107.
中草药和天然植物有效成分提取新技术——微波协助萃取 总被引:29,自引:0,他引:29
中草药和天然植物有效成分的提取分离是天然药物生产过程中最为关键的环节之一。近年来 ,随着中药现代化进程的加速 ,越来越多的新技术正被逐步采用 ,其中 ,微波协助萃取 (microwave assistedextraction ,MAE)是在传统有机溶剂萃取的基础上发展而来的 ,无论是萃取速度、萃取效率还是萃取物质量均优于常规工艺 ,并以其投资少、设备简单、适用范围广、选择性高、重现性好、无污染等特点而受人瞩目。作者综述了MAE技术的作用原理、特点及其在黄酮类、苷类、多糖、萜类、挥发油等天然产物提取中的最新研究进展 ,并展望了其发展前景。 相似文献
108.
The problem of controlling the quality of raw materials and/or final product of traditional Chinese medicine (TCM) has been studied. Earlier proposed consistency index to assess the consistency of quality of raw materials and/or final product processed or manufactured from different locations or sites has only focused on a single (i.e., the most active) component assuming that the most active component can be quantitatively identified among multiple active components. In this paper, we extend such results to the case of two correlative components. Sampling plans (sample sizes) are obtained for various combinations of study parameters. An example concerning a TCM for treating patients with rheumatoid arthritis is presented to illustrate the use of the proposed method. Some concluding remarks are also provided. 相似文献
109.
《International journal of audiology》2013,52(5-6):466-479
Normative studies were carried out with 8 adult subjects whose averaged evoked responses to auditory stimuli were scored visually and by a number of differently defined quantitative methods (machine scoring). In order to compare different scoring methods a common signal-to-noise ratio measure was introduced based on a model where noise is distributed normally and signal is additive. Visual and machine scoring proved to be approximately equally sensitive, but the latter lends itself to a superior testing procedure which takes only one-third as long for equivalent results and is not contaminated by subjective error. The authors believe that the greatest promise for improving evoked response audiometry lies in the exploration of the new techniques proposed earlier. Progress in proving out one of these techniques, fast periodic stimulation, is reported. 相似文献
110.
Effect of Punarnavine on the cell-mediated immune (CMI) response in metastatic condition was studied using C57BL/6 mice model. Administration of Punarnavine enhanced Natural Killer (NK) cell activity, antibody-dependent cellular cytotoxicity (ADCC) and antibody-dependent complement mediated cytotoxicity (ACC) and the activity was observed in treated group much earlier compared to the metastatic tumor-bearing control. Production of cytokines such as IL-2 and IFN-γ were significantly enhanced by the administration of Punarnavine compared to the untreated metastatic tumor-bearing control. Peaks of pro-inflammatory cytokines such as IL-1β, IL-6 and TNF-α were significantly lowered by Punarnavine administration compared to metastatic control. The level and expression of TIMP-1 was also enhanced by the administration of Punarnavine compared to metastatic tumor bearing control. These results indicate Punarnavine could enhance the immune response against metastatic progression of B16F-10 melanoma cells in mice. 相似文献