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91.
In a prospective, double-blind trial prophylactic cotrimoxazole produced a highly significant reduction in the incidence of bacteriuria after prostatectomy. Only two out of 38 patients who received the drug developed bacteriuria compared with 19 out of 36 patients on placebo. Klebsiella-Enterobacter spp and coagulase-negative staphylococci were responsible for most infections. Although co-trimoxazole prophylaxis is obviously effective, widespread use might increase the incidence of bacterial resistance. 相似文献
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IA Frid VI Stoliarov AI Evtiukhin MI Bernshte?n NP Fadeev 《Canadian Metallurgical Quarterly》1976,116(6):84-88
The authors report the data on changes in peripheral circulation, depending on the kind of anesthesia, the amount of operative blood loss, alterations in circulating blood volume and localization of tumor in patients with cancer of the lung, esophagus and cardia. Totally, 35 patients (15--lung cancer, 10--esophageal cancer, 10--cancer of the cardia) were explored. In 25 cases fluothane was used as the main anesthetic, in 10--neuroleptanalgesia. The state of peripheral circulation was estimated by the period semielimination of radioactive xenon-133 from the muscle depot. It was found that alterations in peripheral circulation were not dependent on tumor localization, the use of fluothane and neuroleptanalgesia is associated with similar changes in peripheral blood flow and, finely, an increased loss of blood results in more pronounced alterations in peripheral circulation. 相似文献
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A simple, accurate method for demonstrating very small areas of endothelium is described. Some possible fields for further investigation are suggested. An outline of the possible normal mechanism of endothelial regeneration is described. 相似文献
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以宁夏枸杞芽茶、枸杞叶茶为原料,利用热水浸提(料液比1∶40、温度96℃、时间30 min)制备枸杞芽茶与叶茶提取物并对其所含的化学成分含量进行测定,采用HPLC对枸杞芽茶与叶茶提取物中游离氨基酸的组成进行了分析,利用DPPH自由基、ABTS自由基、超氧阴离子自由基清除率、总还原力为指标对枸杞芽茶、叶茶茶汤提取物的抗氧化活性进行分析评价。结果表明,枸杞芽茶、枸杞叶茶提取物中多酚含量分别为6.32%、2.96%。枸杞芽茶与叶茶提取物中天冬氨酸(3230.41、2440.96μg/g)、天冬酰胺(3754.77、3495.57μg/g)、组氨酸(5585.26、2825.17μg/g)以及亮氨酸(4376.09、1051.00μg/g)含量较为丰富。枸杞芽茶与叶茶提取物相比抗氧化活性较强,二者对DPPH自由基(IC50:147.63、241.23μg/m L)、ABTS自由基(IC50:109.87、145.32μg/m L)以及超氧阴离子自由基(IC50:46.58、54.32μg/m L)均具有良好的清除能力,与叶茶相比,枸杞芽茶具有更好的抗氧化活性。 相似文献
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Young Heui Kim Ki Soo Kim Chang Sung Han Hong Chul Yang Sun Hee Park Kang II Ko Soo Hee Lee KI HO Kim Nam Ho Lee Jung MI Kim Kyunghun Son 《International journal of cosmetic science》2007,29(6):487-488
In order to search for new active cosmetic ingredients of natural origin, we screened about 60 plants collected from Jeju Island, which is located in the southernmost part of the Republic of Korea. We investigated their free radical scavenging activity, elastase inhibition activity, and reduction of MMP-1 mRNA expression for the development of anti-aging ingredients as raw materials for use in cosmetics. In the free radical scavenging capacity assay, 12 extracts, including Typha orientalis (seed) and Torreya nucifera (leaf), showed significant free radical scavenging activity (up to SC50 < 30 μg/ml). Among these extracts, Nymphaea tetragona (rhizome) extract showed the highest free radical scavenging activity (SC50 = 4.7 μg/ml). In the anti-elastase inhibition assay, seven extracts, including T. orientalis (seed) and Persicaria hydropiper (whole plant), showed high inhibitory activity (>50% at 100 μg/ml). Among these extracts, P. hydropiper (whole plant) extract showed the highest elastase inhibition activity (IC50 = 46.7 μg/ml). In the MMP-1 expression assay using RT-PCR, T. orientalis (seed), Pyrrosia hastata (root), and Capsicum annum (whole plant) showed slightly lower inhibition activity than EGCG, which was used as a control. Furthermore, four extracts, including P. hydropiper (whole plant), Filipendula glaberrima (root), N. tetragona (root), and Camellia japonica (leaf), completely inhibited the expression of MMP-1 in human fibroblast cells. The results showed that four of the 60 plant extracts may hold potential for use as natural active ingredients for anti-aging cosmetics. 相似文献
100.
目的:体外研究罗非鱼鱼皮胶原多肽对人结肠癌细胞系LoVo增殖能力的影响,并初步探讨其作用机理。方法:体外培养人结肠癌LoVo细胞,噻唑蓝(methylthiazolyldiphenyl-tertrazolium bromide,MTT)法检测罗非鱼鱼皮胶原多肽对细胞增殖的影响;荧光探针染色法观察细胞膜及核的变化;激光共聚焦显微镜观察细胞内活性氧(reactive oxygen species,ROS)表达;比色法检测细胞线粒体呼吸链酶复合物Ⅰ和Ⅲ的活性。结果:罗非鱼鱼皮胶原多肽对LoVo细胞的增殖具有一定的抑制作用,当质量浓度为100 mg/mL、作用48 h时,抑制率达到55.03%(P<0.05);与空白对照组相比,经胶原多肽作用后,LoVo细胞核浓缩,细胞膜出现不完整,细胞凋亡;且细胞内活性氧水平表达显著增加(P<0.05),细胞内线粒体呼吸链复合物Ⅲ的活性显著降低(P<0.05),但对线粒体呼吸链复合物Ⅰ的活性无影响。结论:罗非鱼鱼皮胶原多肽对人结肠癌细胞具有一定的增殖抑制作用,可能与抑制线粒体呼吸链复合物Ⅲ活性,使胞内ROS水平增加,破坏细胞膜形态有关。 相似文献