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41.
Poly(arylene-1,2,4-oxadiazole)s (PAOs) bearing flexible, linear side chains, 3a - c , were prepared by solution cyclodehydration of their precursors, poly(arylene acyloylamide oxime)s (PAAs), 2a - c , which were synthesized by solution polycondensation of 2,5-bis(n-alkoxymethyl)-terephthaldiamide oximes (DIS-TADO), 1a - c , with terephthaloyl dichloride (TPC). The length of the n-alkoxy group was varied from methoxy via butoxy to octyloxy. The reduction of the phase transition temperatures and the enhancement of the solubilities of 3a - c were greatly affected by the length of the side chains. PAOs with longer side chains, 3b and 3c , are nematic type liquid-crystalline polymers.  相似文献   
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OBJECTIVES: To determine the number of polio survivors living in Kitakyushu, Japan, and the prevalence of post-polio syndrome. DESIGN: Cross-sectional survey in Kitakyushu. SUBJECTS/PATIENTS: A total of 342 possible polio survivors were selected from the list of physically disabled persons' certificates administered by the Department of Health and Welfare, Kitakyushu City Government. METHODS: A self-administered questionnaire concerning the diagnosis, paralysis, limitation in daily living, and use of adaptive devices was mailed to the 342 possible polio survivors. RESULTS: By confirmation of the diagnosis, 241 of the 342 turned out to be polio survivors, and the number of polio survivors per population of 100,000 amounted to 24.1. Of the polio survivors, 85% complained of new health problems such as difficulty in climbing stairs, muscle weakness, difficulty in walking, or fatigue. According to Halstead's criteria, 180 polio survivors suffered from post-polio syndrome, and the prevalence of post-polio syndrome in Kitakyushu was 18.0 per population of 100,000. CONCLUSIONS: This survey revealed the number of polio survivors, and the prevalence of post-polio syndrome in Kitakyushu, Japan.  相似文献   
44.
缺血再灌流肾组织内皮素—1动态变化的实验研究   总被引:7,自引:1,他引:6  
在大鼠肾缺血60分钟再灌注的模型上观察不同时相肾静脉血、肾皮质、外髓和内髓的内皮素1(ET1)浓度变化,肾组织ET1光镜和电镜免疫组织化学变化。结果发现:缺血再灌流肾组织ET1基因表达及分泌明显增强,主要分布在血管内皮细胞及平滑肌细胞、系膜细胞、肾小管上皮细胞。其分布特点与细胞类型和活性有关。本实验结果提示了缺血再灌注肾内ET1的变化规律。  相似文献   
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我们用哈白兔以3%凝固气油致25%Ⅲ°烧伤休克持续了3h复苏的动物模型研究了丹参、维生素E、抗氧化剂协同治疗烧伤休克的作用,效果显著。第5天SOD活性和MDA值均达到伤前水平,提高了动物存活时间。各项生化指标和病理证实,该组实验动物脏器无明显病变,说明联合用药,不仅可以有效的清除氧自由基,还能拮抗脂质过氧化作用,对脏器有较好的保护作用。  相似文献   
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The effects of vagal and sympathetic nerves on the transmembranepotentials of cardiac cells of toad were observed by means of microelectrodetechnique.The vagal nerve was stimulated there would be an increase in restingpotential and acceleration in repolarization of action potential(AP).However,ifatropine was used before stimulation the above-mentioned phenomena woulddisappear.When the sympathetic nerve was stimulated the AP amplitudeincreased,but resting potential(RP)remained the same.The increase of APresulted from the increases of overshoot.When the sympathetic nerve wasstimulated although the heart rate increased and the duration of AP wasshortened,the plateau phase of AP was prolonged.These results suggest that theeffects of vagal and sympathetic nerves on the transmembrane potential of cardiacventricular cells are coordinated and the normal characteritics of transmembranepotential are maintained by both the vagal and sympathetic nerves.  相似文献   
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Excretion of 1,2,4-benzenetriol in the urine of workers exposed to benzene   总被引:5,自引:0,他引:5  
Urine samples were collected from 152 workers (64 men, 88 women) who had been exposed to benzene, 53 workers (men only) exposed to a mixture of benzene and toluene, and 213 non-exposed controls (113 men, 100 women). The samples were analysed for 1,2,4-benzentriol (a minor metabolite of benzene) by high performance liquid chromatography. The time weighted average solvent exposure of each worker was monitored by diffusive sampling technique. The urinary concentration of 1,2,4-benzentriol related linearly to the intensity of exposure to benzene both in men and women among workers exposed to benzene, and was suppressed by toluene co-exposure among male workers exposed to a mixture of benzene and toluene. A cross sectional balance study in men at the end of the shift of a workday showed that only 0.47% of benzene absorbed will be excreted into urine as 1,2,4-benzenetriol, in close agreement with previous results in rabbits fed benzene. The concentration of 1,2,4-benzenetriol in urine was more closely related to the concentration of quinol than that of catechol. The fact that phenol and quinol, but not catechol, are precursors of 1,2,4-benzentriol in urine was further confirmed by the intraperitoneal injection of the three phenolic compounds to rats followed by urine analysis for 1,2,4-benzenetriol.  相似文献   
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