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81.
诺迪康对心脏活动的药理学作用 总被引:5,自引:0,他引:5
目的 :探讨诺迪康对心脏活动的药理学作用。方法 :运用 ms2 0 0 0多媒体生物信号处理系统 ,经 Straub法制备离体蛙心灌流标本并检测心脏活动 ,利用血流动力学方法检测家兔的心室活动等相关指标。结果 :2 0 9mg/L 诺迪康组的心肌收缩力增强 4 0 .38% (n =2 1,P <0 .0 0 1) ,4 18mg/L 诺迪康组的心肌收缩力增强 76 .4 4 % (n =17,P <0 .0 5 ) ,6 2 7mg/L 诺迪康组的心肌收缩力增强 10 4 .95 % (n =2 5 ,P <0 .0 1) ,对照组的心肌收缩力无明显变化 (n =2 5 ,P >0 .5 ) ;三个实验组及对照组对离体蛙心率均无作用 ,P >0 .0 5 ;家兔血流动力学方面 ,诺迪康组的 dp/dtmax增加了 2 1.0 8% (n =10 ,P <0 .0 5 ) ,其他各指标在对照组及诺迪康组均未见显著变化。结论 :诺迪康能增强心肌收缩力且有明显的剂量效应关系 ,可加速心肌的收缩速度但对心肌舒张无明显影响 相似文献
82.
提取青蒿素实验条件的研究 总被引:8,自引:0,他引:8
对从青蒿叶中提取青蒿素的各种方法及实验条件进行实验比较,结果表明,采用索氏提取法及以B号油为溶剂,具有提取率较高,时间短、操作方便、耗油少等特点。 相似文献
83.
84.
N. Ya. Popova A. I. Antokhin N. V. Adrianov L. Z. Tret'yakova Yu. A. Romanov 《Bulletin of experimental biology and medicine》1991,112(4):1486-1488
Department of Biology, Medico-Biological Faculty, and Applied Research Laboratory of Ecology, Toxicology, and Metabolism of Medicinal Preparations, attached to the Department of Biochemistry, Medico-Biological Faculty, N. I. Pirogov Second Moscow Medical Institute. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 112, No. 10, pp. 418–419, October, 1991. 相似文献
85.
K. S. Us P. M. Klodt V. S. Kudrin A. Ya. Sapronova R. U. Ostrovskaya M. V. Ugryumov K. S. Rayevsky 《Neurochemical Journal》2007,1(2):138-142
The level of spontaneous and K+-stimulated release of endogenous glutamate was studied in experiments on slices of brain cortex of Wistar rats. Pronounced spontaneous release of the neuromediator and its increase under conditions of stimulation were registered by high-performance liquid chromatography with electrochemical detection. The effect of the nootropic and neuroprotective dipeptide Noopept (GVS-111) on release of glutamate was investigated. The peptide in concentrations of 10?5 and 10?6 M caused a statistically significant decrease in spontaneous and K+-stimulated glutamate release. This effect could be the basis of the neuroprotective action of the peptide, suggesting that further studies of Noopept as neuroprotector are very promising. 相似文献
86.
目的:研究肺癌放射导向手术中肿瘤及正常组织P糖蛋白(P-gp)、Ki-67抗原表达与放射性核素摄取比(T/NT)的关系.方法:采用免疫组化方法和显微图像分析技术,测定32例接受放射导向手术的肺癌病人P-gp和Ki-67抗原表达,分析P-gp和Ki-67的标记指数(LI)与T/NT之间的相关性.结果:P-gp和Ki-67的LI和肺癌病人T/NT之间均有相关性(r=-0.61,P=0.0002; r=0.75,P=0.0001).结论:Ki-67的LI越高(肿瘤增殖越旺盛),T/NT值越高;P-gp阳性的肿瘤,T/NT值较低. 相似文献
87.
88.
目的 了解中缅边境一线县、二线县、及一线三个县的一线自然村、二线自然村的疟疾流行情况,为制定边境地区疟疾防治措施提供科学依据。方法 采用IFAT对中缅边境沧源、耿马及孟连一线县与双江县、永德县二线县,边境线3县一线自然村和二线自然村进行疟血清流行病学调查,用电脑软件EPI6X2检验法进行数据分析。结果一线县抗体阳性率23.88%(568/2379),二线县抗体阳性率1.40%(10/712),一线县显著高于二线县(x2=180.54;P<0.01)。一线县的一线自然村抗体阳性率33.05%(467/1413),二线自然村抗体阳性率10.46%(101/966),一线自然村显著高于二线自然村(x2=159.92;P<0.01)。结论IFAT抗体阳性率和阳性GMRT说明靠近边境地带比远离边境的地带疟疾流行更为严重。应加强出入境人员的防治工作,才能控制边境疟病流行。 相似文献
89.
We have previously identified two broad electrophysiological classes of spiral ganglion neuron that differ in their rate of accommodation ( Mo & Davis, 1997 a ). In order to understand the underlying ionic basis of these characteristic firing patterns, we used α-dendrotoxin (α-DTX) to eliminate the contribution of a class of voltage-gated K+ channels and assessed its effects on a variety of electrophysiological properties by using the whole-cell configuration of the patch-clamp technique. Exposure to α-DTX caused neurons that initially displayed rapid accommodation to fire continuously during 240 ms depolarizing test pulses within a restricted voltage range. We found a non-monotonic relationship between number of action potentials fired and membrane potential in the presence of α-DTX that peaked at voltages between –40 to –10 mV and declined at more depolarized and hyperpolarized test potentials. The α-DTX-sensitive current had two components that activated in different voltage ranges. Analysis of recordings made from acutely isolated neurons gave estimated half-maximal activation voltages of –63 and 12 mV for the two components. Because α-DTX blocks the Kv1.1, Kv1.2 and Kv1.6 subunits, we examined the action of the Kv1.1-selective blocker dendrotoxin K (DTX-K). We found that this antagonist reproduced the effects of α-DTX on neuronal firing, and that the DTX-K-sensitive current also had two separate components. These data suggest that the transformation from a rapidly adapting to a slowly adapting firing pattern was mediated by the low voltage-activated component of DTX-sensitive current with a potential contribution from the high voltage-activated component at more depolarized potentials. In addition, the effects of DTX-K indicate that Kv1.1 subunits are important constituents of the underlying voltage-gated potassium channels. 相似文献
90.
V. V. Pisarev N. E. Moskaleva Yu. B. Zverkov L. B. Smirnova V. G. Belolipetskaya Ya. V. Sukhanov 《Pharmaceutical Chemistry Journal》2005,39(2):104-107
A reproducible and sensitive analytical procedure has been developed for the quantitative determination of enalapril and enalaprilat in the blood plasma by high-performance liquid chromatography with mass-spectrometric detection (HPLC/MS). For increasing the sensitivity and reproducibility of analyses, the samples were treated with diazomethane in order to obtain methyl esters of the analyzed compounds. The quantitative determination was carried out using the internal standard method; the internal standard was captopril. The detection was performed in the positive ion mode for ions with m/z = 377 (enalaprilat methyl ester), 391 (enalapril methyl ester), and 267 (captopril methyl ester). Enalapril, enalaprilat, and captopril were isolated from the blood plasma and purified by means of solid-phase extraction. The calibration plot is linear in the concentration range from 0.5 to 200 ng/ml. The detection limits for both enalaprilat and enalapril in the blood plasma are 0.1 ng/ml.__________Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 39, No. 2, pp. 49 – 52, February, 2005. 相似文献