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11.
Cernitins are preparations obtained from plant pollen which contain numerous compounds of potential biological significance. This work deals with the influence of cernitins upon acute paracetamol toxicity in mice. The survival rate and indices of hepatic injury: aminotransferase and alkaline phosphatase activities, bilirubin level in serum, glutathione and cytochrome P-450 content in liver, liver weight, histopathologic picture of the liver and presence of glycogen and lipids in stained liver sections, under different experimental protocols, were determined. It was found that cernitins are able to increase the survival rate of mice and reduce liver injury in acute paracetamol poisoning. Cernitins are more effective when administered after, rather than before, a dose of paracetamol. The possible mechanism through which cernitins may act is discussed.  相似文献   
12.
采用人外周血淋巴细胞非程序DNA合成(UDS)试验和人胚肺成纤维细胞转化试验,测试了煤焦沥青烟雾提取物(ECTPF)对人体细胞的细胞毒性和遗传毒性。UDS试验结果表明,ECTPF可使淋巴细胞UDS值明显增加,并有剂量一反应关系。引起半数淋巴细胞死亡的浓度(LC50)为33.8μg/ml。细胞转化试验表明,ECTPF能诱发人胚肺成纤维细胞明显的形态学转化,且转化细胞具有部分恶性转化细胞的特性。引起半数人胚肺成纤维细胞生长抑制的浓度为41.3μg/ml。实验结果提示,ECTPF是一种具有细胞毒性和遗传毒性的物质。  相似文献   
13.
The anthelmintic activity of aqueous extracts (0.25–50 mg/mL) from 14 plant species that represent seven families of the Sudanese flora was examined using the free living rhabditid nematode, Caenorhabditis elegans as a test organism. Extracts of Balanites aegyptiaca and Sesbania sesban were the most effective (LC50, 0.8 and 8.0 mg/mL, respectively). Extracts of Albizzia anthelmintica, Cymbopogen narvatus, Abrus precatorius, Rhyncosia minima, Striga hermonthica and Anogeissus leiocarpa (LC50, 9.5–84.6 mg/mL were less effective in this model test system. Extracts of six plant species, Albizzia malacophylla, Gardenia lutea, Physostigma mesoponticum, Salvadora persica, Xeromphis nilotica and Waltheria indica had no effect upon C. elegans survival.  相似文献   
14.
Summary Antibodies against phosphate-buffered-saline extracts (SE) of non-acetylcholine receptor (AChR) skeletal muscle antigens were found in patients with myasthenia gravis (MG). The antigenicity of SE was distributed in three fractions with molecular masses of over 200 kDa, 90–150 kDa and 7–14 kDa on gel filtration. These fractions shared common antigenicities. Further analysis of 90–150 kDa fractions on sodium dodecyl sulphate polyacrylamide gel electrophoresis showed five major bands, ranging from 105 kDa to 275 kDa. The antibodies against SE were detected in 52% (58/112) of the MG patients; incidence and titres were higher in the thymoma group (n=21; 90% and 0.872 respectively) than in the non-thymoma group (n=91; 43% and 0.200, P<0.001). In patients without a thymoma, these antibodies were frequently observed in late-onset disease and the severe generalized form (P<0.01). In 4 of 7 ocular MG patients without anti-AChR antibodies, low but appreciable levels of anti-SE antibodies were found. In 73% (11/15) of generalized MG patients treated with prednisolone and thymectomy, anti-SE antibody titres changed in association with those of anti-AChR antibodies and with the clinical course. Both antibody titres increased synchronously in patients who developed crises.  相似文献   
15.
N. P. Boye    O. P. Salo    N. Hyldebrandt    J. A. Wihl    A. Bevan    R. I. Harris  J. R. Lovely 《Allergy》1990,45(4):241-248
The safety and efficacy of two birch pollen extracts, one chemically conjugated to alginate (Anjuvac) the other adsorbed to aluminium hydroxide (Alutard), were investigated in an open multicentre comparative study of 63 birch pollen allergic patients. Both extracts decreased the nasal symptoms during the birch pollen season. The changes in specific IgE and IgG were much the same in both treatment groups. The adverse reactions recorded were mild in both groups, but more frequent in the Anjuvac group, probably because of a more aggressive dose schedule though there were twice as many asthmatics in the Anjuvac group. The two investigated allergen extracts were useful alternatives for immunotherapy.  相似文献   
16.
We report on a 29-year-old woman suffering from hay fever due to grass and olive tree pollens. She developed recurrent pericarditis during her first course of immunotherapy with an alum-adsorbed pollen extract. A causal relationship was established between the allergen injections and the acute pericarditis episodes on two consecutive occasions, which presented with blood eosinophilia. Blood cultures and serological tests for microorganisms were negative. There were no signs of autoimmune disease or systemic vasculitis. To the best of our knowledge, allergen immunotherapy-induced pericarditis has not been previously reported.  相似文献   
17.
目的:探讨心肌匀浆上清液对大鼠骨髓间质干细胞(MSCs)诱导分化的影响。 方法: 体外分离培养大鼠MSCs,检测纯度。于原代培养第3 d加入自体心肌匀浆上清液持续作用1周。3周后,观察细胞形态,采用免疫细胞化学检测肌球蛋白重链和心肌特异性肌钙蛋白-T,RT-PCR方法检测Nkx2.5、α-MHC和ANP基因的表达。 结果: 大鼠MSCs经诱导后,表达肌球蛋白重链、心肌特异性肌钙蛋白-T和Nkx2.5、α-MHC基因,但未表达ANP基因,也未观察到肌管和闰盘样结构。 结论: 心肌匀浆上清液对MSCs具有定向诱导分化作用,但诱导不完全,具体机制仍需深入研究。  相似文献   
18.
山东地产药材北沙参浸出物含量测定   总被引:1,自引:0,他引:1  
依据《中华人民共和国药典》附录中记载的浸出物含量测定方法 ,对不同来源、不同加工方法的北沙参进行了水溶性浸出物含量测定 ,为建立北沙参药材质量标准提供了依据。  相似文献   
19.
糖尿病胃轻瘫(DGP)发病率较高,药物治疗存在一定的局限性,部分患者可能出现一定的不良反应,这影响糖尿病的治疗。中药治疗DGP可以有效缓解患者症状,降低现有药物不良反应,辅助控制血糖。现代医家多利用辨证分型组方、经方验方及中成药进行辨病辨证治疗相结合,运用单味药、药对、中药提取物进行个体化治疗。现通过概述中药的多种组方思路,总结其优势,并对中药治疗DGP的现状进行思考与总结,以期中医药治疗DGP得到更好的发挥。  相似文献   
20.
正交试验法优选银翘解毒软胶囊的水煮提取工艺   总被引:3,自引:0,他引:3  
采用L9(3^4)正交设计,以浸膏得率,正丁醇浸出率,绿原酸含量为考察指标,优选银翘解毒软胶囊的水煮提取工艺。结果表明:最佳提取工艺为首次加10倍量水,浸泡30min,煎煮2h,第2次加8倍量水,煎煮1.5h。  相似文献   
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