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91.
余甘子是一种具有较高的食用和药用价值的野生植物资源,风味独特,含有丰富的类SOD活性物质和其他多种具有生物活性的物质,具有清除自由基、抗肿瘤、抗衰老等保健作用。作者提出了余甘予保健口服液的生产工艺流程及配方,并采用改良的Marklund方法测定了类SOD的活力,结果较为满意。 相似文献
92.
研究不同微生物诱导家蝇幼虫表达的抗菌肽特性.用3种不同的病源菌通过针刺感染的方法诱导家蝇幼虫表达抗菌肽,通过Sephadex G25分离,用Hult mark改进法和抑菌圈测定法作抑菌试验,用毛细管电泳(CE)分析不同微生物诱导得到的抗菌肽样品差异,检测抗菌肽的热稳定性和酸碱耐受性.发现不同微生物诱导产生的家蝇抗菌肽具有广谱抑菌性,但不同样品对不同病源菌抑菌活性有差异,不同测定抑菌效果的方法对抑菌结果有影响,各种抗菌肽样品CE蛋白谱具有明显不同.抗菌肽样品都具有热稳定性和酸碱耐受性.说明不同微生物诱导产生的家蝇抗菌肽类型以及抗菌肽含量与诱导源有关,抗菌肽为家蝇幼虫体内固有成分,诱导增加了抗菌肽的表达量同时刺激新抗菌肽的产生.用志贺氏菌、金黄色葡萄球菌、鼠伤寒沙门氏菌诱导家蝇幼虫可产生较多含量高活性好的抗菌肽. 相似文献
93.
对管碟法测定Nisin效价的条件进行了研究,考察了几个参数的影响,得出了Nisin测定的最佳条件:90mm培养皿中培养基加量为15mL,Na2HPO4·12H2O质量浓度1g/dL,菌悬液浓度109CFU/mL,琼脂质量浓度1g/dL,培养基pH值7.0,牛津杯中样品加液量100μL.在此条件下,Nisin效价在5~100IU/mL,其对数值与抑菌圈直径有较好的线性关系. 相似文献
94.
M. R. Goldberg M. W. Lo T. E. Bradstreet M. A. Ritter P. Högland 《European journal of clinical pharmacology》1995,49(1-2):115-119
This was a 2-period randomized, crossover study in 8 healthy males to determine the effects of cimetidine (400 mg q.i.d. for 6 days) on the pharmacokinetics and pharmacodynamic effects of the angiotensin II receptor antagonist, losartan (100 mg). Cimetidine increased the AUC for losartan 18% without affecting the AUC for E-3174, the active metabolite of losartan. The increase in plasma renin activity following losartan was not affected by cimetidine (maximum mean increases 12.6 and 12.1 ng Ang I·ml–1·h–1 without and with cimetidine, respectively). These results indicate that cimetidine does not appear to alter the pharmacokinetics or pharmacodynamics of losartan to a clinically significant extent. 相似文献
95.
Stability of the Defibrillation Probability Curve with the Development of Ventricular Dysfunction in the Canine Rapid Paced Model 总被引:1,自引:0,他引:1
PAUL A. FRIEDMAN DAVID A. FOLEY TIMOTHY F. CHRISTIAN MARSHALL S. STANTON 《Pacing and clinical electrophysiology : PACE》1998,21(2):339-351
Most patients with implantable defibrillators have diminished cardiac function. Progressive heart failure might impair defibrillation efficacy, leading to interpreted device, failure. This study sought to determine the effect of ventricular dysfunction on defibrillation energy using a biphasic endocardial system. Eleven dogs were ventricularly paced at 225 pulses/min for 2 weeks to induce ventricular dysfunction, and five control dogs remained unpaced. Dose response defibrillation probability curves were generated for each animal at baseline, after 2 weeks (at which time the pacemakers were turned off in the paced group), and then 1 week later. The defibrillation thresholds, ED20 , ED50 , and ED80 (the 20%, 50%, and 80% effective defibrillation energies, respectively) were determined for each dog at each study. In the paced dogs, the mean ejection fraction fell from 55% to 25% after pacing (P < 0.0001), and rose to 46% after its discontinuation (P = 0.0002). The defibrillation threshold, ED20, ED50 , and ED80 remained unchanged in both the control and paced groups for all three studies, even after adjustment for dog weight or left ventricular mass. Rapid pacing produced no change in left ventricular mass. It induced ventricular cavity dilatation and wall thinning, which had opposing effects on defibrillation energy requirements, resulting in no net change of the ED50 in heart failure. In conclusion, the defibrillation efficacy of a biphasic transvenous system is not changed by the development of heart failure using the rapid paced canine model. 相似文献
96.
97.
蝙蝠葛碱对奎尼丁诱发的豚鼠乳头肌早后去极化及触发活动的作用 总被引:4,自引:1,他引:3
用标准微电极技术观察了中药蝙蝠葛的有效成分蝙蝠葛碱对奎尼丁诱发的豚鼠乳头肌早后去极化及触发活动的影响. 结果表明,奎尼丁2 μmol·L-1能诱发豚鼠乳头肌早后去极化及触发活动,早后去极化的发生率为8/20, 幅值为13.4±2.6 mV, 起始电位为-42±5 mV, 触发活动的发生率为2/20. 蝙蝠葛碱20 μmol·L-1能明显抑制奎尼丁诱发的早后去极化及触发活动,早后去极化的发生率为4/20,幅值为7.3±1.1 mV,无触发活动. 结果提示蝙蝠葛碱具有抗早后去极化所致心律失常. 相似文献
98.
取代四氢异喹啉衍生物的合成及其生物活性 总被引:7,自引:0,他引:7
粉防己碱有钙拮抗作用,临床试用于治疗高血压,其裂解产物钙拮抗作用降低,但有α-肾上腺素能受体拮抗作用,本文以裂解物为先导化合物设计合成了两类取代的四氢异喹啉衍生物Ⅲ及Ⅳ。初步药理试验表明:大部分化合物有α-肾上腺素能受体拮抗作用,少数化合物钙拮抗活性有所增强,其中Ⅲ15,19对正常麻醉大鼠有一定的降压作用、Ⅳ17,19对实验性动物心律失常有明显的保护作用。部分化合物量化计算表明:化合物与α1-受体作用方式可能是形成电荷转移复合物。 相似文献
99.
Abstract Nitric oxide (NO) plays an important physiological role in regulating gastrointestinal motility. Involvement of endogenous NO was evaluated in the response to non-adrenergic, non-cholinergic (NANC) nerve stimulation of the dog sphincter muscle of Oddi. Transmural electrical stimulation (TES), nicotine (10?5M) and K+ (10 mM) produced only a relaxation in the sphincter muscle strips contracted with substance P, which was not potentiated by atropine. The TES-induced relaxation was abolished by tetrodotoxin (3 times 10?7 M) and oxyhaemoglobin (1.6 times 10?5 M), but not affected by atropine (10?7 M), propranolol (10?7 M), phentolamine (10?7 M), indomethacin (10?6 M), chole-cystokinin (CCK, 10?8 M) and vasoactive intestinal polypeptide (VIP, 10?8 M). The relaxation was also abolished by treatment with NG-nitro-L-arginine (L-NA, 10?5 M), an NO synthase inhibitor. Nicotine produced a transient relaxation, which was abolished by tetrodotoxin, hexamethonium (10?5 M) and L-NA, but not affected by atropine and NG-nitro-D-arginine (D-NA, 10?5 M). The addition of K+ elicited a transient relaxation, which was abolished by tetrodotoxin and L-NA. The inhibitory effects of L-NA were antagonized by L-arginine (10?3 M). The presence of neurons containing nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase was histochemically demonstrated in the sphincter of Oddi. These findings may indicate that TES, nicotine and K+ liberate NO from NANC inhibitory nerve which is involved in the relaxation of the dog sphincter of Oddi. The muscular tone does not seem to be regulated by cholinergic nerves under the experimental conditions used. 相似文献
100.
Site selection for fat autotransplantation: Some observations 总被引:4,自引:0,他引:4
The use of autologous fat for implantation has recently received renewed attention in the plastic surgery literature. Autologous fat reportedly has been used for the treatment of wrinkles and Romberg's disease, and for buttock and breast augmentation. While some measure of success has been achieved, many surgeons report that substantial resorption of fat tissue occurs at the site of implantation. There is lack of unanimity regarding the ideal site for extraction or injection in order to minimize fat resorption. Adipose tissue samples were taken from women undergoing surgical procedures on the abdomen, gluteal-femoral region, and breast. Facial adipose tissue samples from men and women were also analyzed. Adipocytes were isolated chemically and sized microscopically. Activity of the lipogenic enzyme adipose tissue lipoprotein lipase (ATLPL) was measured in frozen samples. Results suggest that femoral site samples are somewhat larger (NS) and have greater lipogenic activity (p<0.03) than other sites. In our study, small facial samples had very low or unmeasurable levels of ATLPL activity. Perhaps cell size and lipogenic activity should be considered when selecting tissues for autotransplantation. 相似文献