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51.
A growing body of evidence supports the trigger role of free radicals in the delayed functional and metabolic myocardial recovery following cardiopulmonary bypass (CPB) in humans, thus opening the field to specific therapies. This clinical study was designed to evaluate, in 15 patients undergoing aortic valve replacement, whether the extent of CPB- and reperfusion-induced lipid peroxidation, ascorbate depletion, tissue necrosis, and cardiac dysfunction is reduced by orally administered EGb 761, a Ginkgo biloba extract withpotent in vitro antiradical properties. Patients received either EGb 761 (Tanakan, 320 mg/day, n = 8) or a matching placebo (n = 7) for 5 days before surgical intervention. Plasma samples were obtained from the peripheral circulation and the coronary sinus at crucial stages of the operation (i.e., before incision, during ischemia, and within the first 30 minutes post-unclamping), and up to 8 days postoperatively. Upon aortic unclamping, EGb 761 inhibited the transcardiac release of thiobarbituric acid species (p ` 0.05), as assessed by high-performance liquid chromatography, and attenuated the early (5–10 minute) decrease in dimethylsulfoxide/ascorbyl free radical levels, an electron spin resonance index of the plasma ascorbate pool (p ` 0.05). EGb 761 also significantly reduced the more delayed leakage of myoglobin (p = 0.007) and had an almost significant effect on ventricular myosin leakage (p = 0.053, 6 days postoperatively). The clinical outcome of recovery of treated patients was improved, but not significantly, compared with untreated patients. Our results demonstrate the usefulness of adjuvant EGb 761 therapy in limiting oxidative stress in cardiovascular surgery and suggest the possible role of highly bioavailable terpene constituents of the drug.  相似文献   
52.
大鼠背部20%光辐射Ⅲ度烧伤7天后的焦痂提取液及1:4、1:8稀释液能对正常大鼠肝线粒体呼吸产生明显的抑制作用,相同方法制成的正常皮提取液只呈轻度抑制,1:4稀释液已无抑制作用,两者丙二醛含量相差悬殊,丙二醛含量与抑制率呈相关,但进一步分析表明这种相关为共存现象,丙二醛含量增高不是呼吸率下降的直接原因。丙二醛增高与膜脂双层的破坏有关,内膜能化作用实验表明,当膜脂受到一定程度破坏时,能化作用受到抑制。然而在能化作用未表现异常时,呼吸率已呈一定程度抑制,故呼吸率抑制还受到提取液其他组分的影响。  相似文献   
53.
The influence of a fraction obtained from Galeopsis ladanum L. on the central nervous system of rodents was examined. The results of these investigations show that the fraction impeded CNS activity. It is practically nontoxic and at a dose of 2000 mg/kg i.p. it does not have a soporific influence on mice. It reduces considerably the spontaneous locomotor activity of mice as well as the locomotor activity of mice stimulated by caffeine, but did not influence the locomotor activity induced by amphetamine. The extract did not exhibit a synergetic effect with barbiturates. The results suggest that the pharmacological activity of the extract resembled the activity of drugs which generally depress the CNS, being on the border between ataractic and sedative drugs.  相似文献   
54.
A case of small round and spindle cell sarcoma with neuronal differentiation and oncocyte-like features is presented. The tumor was encountered in a 32 year old Japanese woman with an initial presentation of palpable tumor in the left lateral region of the thorax. The resected tumor was a partially well encapsulated whitish medullary one and consisted of small round and spindle tumor cells, together with so-called rhabdoid cells in the small round cell area. Although pseudorosettes were often observed, true rosette formation could not be detected anywhere. Ultrastructurally, despite a histologic variety of tumor cells, most tumor cells possessed numerous mitochondria, some of which occasionally contained abnormal filamentous or crystalloid structures. Various amounts of microfilaments were present in most tumor cells and microtubules were present in a few. A minority of small round cells possessed a small number of neurosecretory granules, especially in short cytoplasmic processes. A positive immunoreaction for neuron specific enolase was found by immunohistochemical examination in several small round tumor cells and for neurofilaments in lesser numbers. Despite the lack of S-100 protein, MB2 was detected in both small round and spindle cells. On the basis of these findings, the tumor of the present case corresponds to malignant peripheral nerve sheath tumor with neuronal differentiation and oncocytic features.  相似文献   
55.
Immunized rabbits that were aerosol challenged for 2 to 3 wk with pigeon dropping extract, an etiologic agent of hypersensitivity pneumonitis, developed chronic pulmonary inflammation associated with cell-mediated immunity in bronchoalveolar cells. However, prolonged aerosol challenge for 12 wk resulted in the diminution of pulmonary inflammation (modulation) and the loss of demonstrable cell-mediated immunity. This was probably not due to loss of sensitized lymphocytes that mediated pulmonary inflammation. Furthermore, rabbits undergoing modulation when they were challenged with an unrelated antigen were refractory to the development of pulmonary inflammation for at least 9 wk. After this refractory period, animals reimmunized and aerosol challenged with pigeon dropping extract displayed an anamnestic response and produced pulmonary lesions that were strikingly similar to the histopathology of human hypersensitivity pneumonitis.  相似文献   
56.
目的 探讨银杏叶提取物对在体缺血冷藏再灌注后肺组织ICAM-1和P选择素基因mRNA表达的影响。方法 新西兰白兔30只。随机分为3组:对照组、LPD组和GBE组.建立兔在体缺血冷藏再灌注模型,对照组左肺不灌注肺保护液,阻断左肺门后直接将左肺下叶载体冷藏于10℃肺保存器内2h,再灌注2h;LPD组左肺门阻断后经肺动脉灌注LPD液,余同对照组;GBE组灌注液为合银杏叶提取物(Ginkgo Biloba Extract,GBE)的LPD液,余同LPD组。分别于左肺门阻断前、缺血2h、再灌注2h取左肺组织,RTPCR技术检测P-选择素和ICAM-1基因mRNA的表达;免疫纽化技术检测P-选择素和ICAM-1基因蛋白质产物量。结果 三组在缺血前及缺血2h再灌注前P—selectin基因mRNA表达量及其蛋白质产物免疫组化评分组间均未有显著性差异。再灌注2h后,GBE组P—selectin基因mRNA表达量厦其蛋白质产物免疫组化评分显著低于LPD组和对照组。,缺血前,所有三组ICAM—1基因mRNA表达量均未有显著性差异,在缺血2h后再难注前及再灌注2h后,ICAM—1基因mRNA表达量及其蛋白质产物免疫组化评分在GBE组均显著低于对照组和LPD组。结论 银杏叶提取物可抑制P—selectin和ICAM—1基因mRNA的表达上调,使肺组织P—selectin和细胞间粘附分子-1蛋白产物减少,从而减轻保存肺的缺血再灌注损伤。银杏叶提取物作为肺保护液添加剂,在进一步研究后可以试用于临床肺移植,为中药提取物的开发应用展示了光明的前景。  相似文献   
57.
To observe the effect of Gardenia extract ZG on the adsorption quantity of herpes simplex virus type 1 (HSV-1) so as to explore the mechanism of its antiviral activity, fluorescein isothiocyanate (FITC) was used as the fluorescent probe to label viruses and heparin sodium was used as control. Meanwhile , the effect of Gardenia extract ZG on the adsorption quantity on the surface of Hep-2 cells was determined by flow cytometry. It was demonstrated that adsorption of HSV-1 on the surface of Hep-2 cells exhibited the character of saturation and specificity and heparin sodium could prevent attachment of viruses on these cells. These results are in accord with those reported previously. It was also proved that the manner of drug-use prior to adsorption or simultaneous use of drug and adsorption was better than adsorption prior to drug-use, and the inhibition rates of the former and latter manner were 84. 76% and 82.92% respectively. Three manners of drug-use with Gardenia extract ZG were all effective to reduce the adsorption quantity of viruses, especially the manner of simultaneous use of drug and adsorption with an adsorption inhibition rate of 68.46% . From the above observation, it is apparent that the mechanism of anti-viral activity of Gardenia extract ZG may be via several steps involved in the HSV-1 adsorption.  相似文献   
58.
The classification of some of the extractable birch pollen antigens as allergens was established by crossed radioimmunoelectrophoresis (CRIE). In CRIE the major allergen (antigen 23) exhibited the strongest “radiostaining” and only a few other components of birch pollen extract were visibly radiostained. The major allergen and a preparation containing mainly the minor allergens, antigens 25 and 19, were isolated from a crude aqueous birch pollen extract by a combination of anion-exchange, size-exclusion, and chelate chromatography. Antigen 23 was purified to near homogeneity. The molecular weights and the pIs of antigens 23, 25, and 19 were determined to be 17,000 daltons, pI 5.25 (5.5, 5.0); 25,000 daltons, pI 5.0 (4.9, 5.4); and 29,000 daltons, pI 6.2 (5.4), respectively. The classification of antigen 23 as the major allergen in birch pollen was supported by results of RAST inhibition experiments, RAST screening, and skin prick testing.  相似文献   
59.
60.
A novel naturally occurring antiangiogenic agent isolated from cartilage, referred to as Neovastat (AE-941), was examined for its efficacy against tumor neovascularization and progression. Exposure to Neovastat results in ex ovo antiangiogenic properties in the chorioallantoid membrane of chicken embryo (71% decrease in the angiogenic index as compared to the basic fibroblast growth factor (bFGF) treated control embryos, P < 0.0001). Oral administration of Neovastat inhibits bFGF-induced angiogenesis in the Matrigel mouse model (87.5% decrease in hemoglobin as compared to the bFGF-treated control implants, P < 0.0001). Neovastat also induces a dose response decrease of lung metastases in the Lewis lung carcinoma model (oral administration; 69.1% of inhibition obtained at the maximal dose of 0.5 ml/day, P < 0.0001). Combined with a sub-optimal dose of cisplatinum (2 mg/kg, i.p.), Neovastat (0.5 ml/day) improved the therapeutic index by increasing the antimetastatic efficacy and by exerting a protective activity against cisplatinum-induced body weight loss and myelosuppression. In summary, our experimental data provide evidence of antiangiogenic and antimetastatic properties of Neovastat, following oral administration.  相似文献   
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