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81.
目的探讨醋酸铅对豚鼠内侧橄榄耳蜗传出神经的损害。方法 70只成年健康豚鼠随机分为对照组和实验组。对照组(10只)豚鼠腹腔注射生理盐水1ml,共7次。实验组又分为高铅组和低铅组(各30只),分别每天1次腹腔注射0.25%醋酸铅溶液40mg/kg和10mg/kg,连续一周,分别于停药后14、28天(各15只))进行血铅含量和畸变产物耳声发射(DPOAE)检测,检测完成后断头处死,行基底膜铺片染色。结果实验组醋酸铅染毒后,血清中铅含量迅速升高。对照组和低铅组耳蜗传出神经分布均匀,神经纤维连续,DPOAE出现了不同程度的对侧声抑制效应,低铅组14天和28天抑制幅度分别为3.06±1.19dB和2.86±1.33dB;高铅组14天后耳蜗传出神经纤维连续性中断,乙酰胆碱酯酶终末反应物减少,DPOAE对侧声抑制幅度下降为0.74±0.61dB;高铅组28天后传出神经损害最为显著,DPOAE未引出。结论铅可对豚鼠内侧橄榄耳蜗传出神经产生不可逆性的损害。 相似文献
82.
John Monro Suman Mishra Halina Stoklosinski Kerry Bentley-Hewitt Duncan Hedderley Hannah Dinnan Sheridan Martell 《Nutrients》2022,14(15)
Non-sugar components of kiwifruit reduce the amplitude of the glycaemic response to co-consumed cereal starch. We determined the relative contribution of different non-sugar kiwifruit components to this anti-glycaemic effect. Healthy participants (n = 9) ingested equal carbohydrate meals containing 20 g starch as wheat biscuit (WB, 30 g), and the sugar equivalent of two kiwifruit (KFsug, 20.4 g), either intrinsic or added as glucose, fructose and sucrose (2:2:1). The meals were WB+KFsug (control, no non-sugar kiwifruit components), WB + whole kiwifruit pulp (WB+KF), WB + neutralised kiwifruit pulp (WB+KFneut), WB + low-fibre kiwifruit juice (WB+KFjuice) and WB+KFsug + kiwifruit organic acids (WB+KFsug+OA). All meals were spiked with 100 mg sodium [1-13C] acetate to measure intestinal absorption. Each participant ingested all meals in random order. Blood glucose and breath 13CO2 were measured at ingestion and at 15 min intervals up to 180 min. Compared with WB+KFsug, whole kiwifruit pulp (WB+KF) almost halved glycaemic response amplitude (p < 0.001), reduced incremental area under the blood glucose response curve (iAUC) at 30 min (peak) by 50% (p < 0.001), and averted late postprandial hypoglycaemia. All other treatments suppressed response amplitude half as much as whole kiwifruit and averted acute hypoglycaemia, with little effect on iAUC. Effects on 13CO2 exhalation paralleled effects on blood glucose (R2 = 0.97). Dietary fibre and organic acids contributed equally to the anti-glycaemic effect of kiwifruit by reducing intestinal absorption rate. Kiwifruit flesh effectively attenuates glycaemic response in carbohydrate exchange, as it contains fructose, dietary fibre and organic acids. 相似文献
83.
84.
南川木波罗根皮的化学成分 总被引:1,自引:0,他引:1
目的:研究南川木波罗根皮的化学成分。方法:采用硅胶、Diaion HP20大孔吸附树脂、MCI gel CHP 20P树脂凝胶、Sephadex LH-20凝胶、ODS等柱色谱分离手段,对南川木波罗根皮醇提物的乙酸乙酯部位进行化学成分的分离纯化,根据化合物的理化性质及光谱数据鉴定其结构。结果:分离了9个化合物,分别鉴定为4-羟基苯甲醛(p-hydroxybenzaldehyde)(1),2,4-二羟基苯甲酸(2,4-dihydroxybenzoic acid)(2),香豆酸(p-coumaric acid)(3),儿茶素[(+)catechin](4),(E)-阿魏酸甲酯[(E)-ferulic acid methyl ester](5),E-对-羟基肉桂酸甲酯(p-E-hedroxycinnamic acid methyl ester)(6),norartocarpetin(7),反式氧化白黎芦醇(trans-oxyresveratrol)(8),moracin M(9)。结论:化合物1,2,5,6为首次从桑科植物中获得,化合物3为首次在波罗蜜属植物中发现,而化合物7~9为首次从南川木波罗中分离得到。 相似文献
85.
Yasuto Sasaki Yoshiki Shiba Chikara Hirono Yoshinobu Kanno Tomio Takeuchi Kazuo Umezawa 《Cancer science》1989,80(9):855-860
We have examined the suppressive effect of herbimycin A on the reduction of gap-junctional Intercellular communication that is induced by a tumor-promoting phorbol ester in 3T3-L1 cells. Most cells in growth arrest participated in dye-coupling, as evaluated by the transfer between cells of a fluorescent dye (Lucifer Yellow CH). Treatment of cells with 0.25 μg/ml herbimycin A slightly enhanced the dye-coupling. This enhancement required treatment for periods as long as 24 h. Addition of 100 ng/ml 12-O-tetradecanoylphorbol-13-acetate (TPA) caused a rapid reduction of dye-coupling. However, addition of TPA did not suppress dye-coupling in cells pretreated for more than 24 h with herbimycin A. Pretreatment of cells for less than 6 h with herbimycin A did not suppress the TPA-induced reduction of dye-coupling. These results suggest that herbimycin A suppresses the reduction of gap-junctional intercellular communication that is induced by TPA through enhancement of the ability of the cells to participate in gap-junctional intercellular communication 相似文献
86.
目的:研究术前给予醋酸亮丙瑞林对子宫肌瘤腹腔镜剔除术手术效果影响。方法:研究对象选取我院2012年10月到2017年10月间行子宫肌瘤腹腔镜剔除术患者120例,采用随机数字法将其分为对照组和观察组,每组各60例。对照组患者仅行子宫肌瘤腹腔镜剔除术治疗,观察组患者子宫肌瘤腹腔镜剔除术前,皮下注射醋酸亮丙瑞林预处理。比较两组患者的手术和术后效果指标,同时比较观察组患者治疗前后的血清黄体生成素、卵泡刺激素、雌二醇水平和月经量、子宫体积、肌瘤体积等。结果:观察组患者的术中出血量、盆腔引流量、首次下床活动时间、住院时间均明显低于对照组(P<0.01),观察组患者治疗后的血清黄体生成素、卵泡刺激素、雌二醇水平均明显低于治疗前(P<0.01),月经量、子宫体积、肌瘤体积均明显低于治疗前(P<0.01)。结论:子宫肌瘤腹腔镜剔除术术前给予醋酸亮丙瑞林治疗,能够有效调节患者激素水平和月经量,缩小子宫肌瘤体积,提高术前准备质量,有助于患者手术开展和术后恢复,值得在临床推广。 相似文献
87.
88.
Although medicinal plants have been historically used for diabetes treatment throughout the world, few of them have been validated by scientific criteria. Recently, a large diversity of animal models has been developed to better understand the pathogenesis of diabetes mellitus and new drugs have been introduced in the market to treat this disease. The aim of this work was to review the available animal models of diabetes and some in vitro models which have been used as tools to investigate the mechanism of action of drugs with potential antidiabetic properties. In addition, a MEDLINE/PUBMED search for articles on natural products, pancreatectomy and diabetes mellitus treatment published between 1996 and 2006 was done. In the majority of the studies, natural products mainly derived from plants have been tested in diabetes models induced by chemical agents. This review contributes to the researcher in the ethnopharmacology field to designs new strategies for the development of novel drugs to treat this serious condition that constitutes a global public health. 相似文献
89.
90.
目的:比较甲地孕酮联合NP方案和单用NP方案化疗对晚期非小细胞肺癌生活质量的影响,评价甲地孕酮的临床疗效。方法:将60例晚期非小细胞肺癌患者随机分为治疗组与对照组。治疗组30例,于化疗前2天口服甲地孕酮160 mg,2次/d,同时予NP方案化疗。对照组30例仅接受NP方案化疗。于化疗4周期后评价患者的食欲、体重变化、KPS评分及不良反应。结果:经过4个周期后治疗组食欲、体重、KPS评分改善情况与对照组相比差异有统计学意义(P<0.05)。治疗组主要不良反应为高血压、便秘、血糖升高、皮疹、阴道流血、踝部水肿等反应,经对症处理后可缓解。结论:甲地孕酮可改善晚期非小细胞肺癌患者的生活质量,减轻其不良反应,不良反应可耐受。 相似文献