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排序方式: 共有1961条查询结果,搜索用时 15 毫秒
1.
目的通过研究肺表面活性物质(PS)结合持续气道正压通气(CPAP)治疗新生儿呼吸窘迫综合征(NRDS)的治疗效果,进一步指导NRDS的临床治疗。方法选取于2017年4月-2018年10月间在本院收治的80例确诊为新生儿呼吸窘迫综合征的患儿作为研究对象,随机将患儿分为试验组和对照组,对照组给予持续气道正压通气治疗,试验组在对照组的基础上联合使用PS治疗。结果试验组对于呼吸窘迫缓解的有效率明显高于对照组,在气管插管内滴入PS治疗后试验组的血气情况明显优于对照组,且试验组患儿副作用发生率明显低于对照组,以上指标差异具有统计学意义,P <0.05。结论 PS结合CPAP在新生儿呼吸窘迫综合征的治疗中疗效很好。 相似文献
2.
Yuan Xue Tracy L. Williams Ting Li Joshua Umbehr Liang Fang Weiqun Wang Richard C. Baybutt 《Toxicology in vitro》2005,19(8):1061-1069
This study was to evaluate the effects of cigarette smoke constituents upon type II pneumocyte surfactant production in vitro, and how vitamins A and E may alter the response. Freshly isolated type II pneumocytes from Sprague–Dawley rats were incubated 20 h in medium with fetal bovine serum that was or was not treated with cigarette smoke. The number of adherent cells was inversely related to the dose of smoke or benzo(a)pyrene. Despite the decreased number of treated cells, the total amount of surfactant per culture well was unchanged, whereas surfactant production per cell was significantly increased (P < 0.05). Vitamin A concentration was significantly (P < 0.05) lower in the smoke-treated serum compared with untreated serum. When vitamin A or E was added to the cigarette smoke-treated serum, cell adherence and surfactant production returned to control values. In conclusion, cigarette smoke constituents or benzo(a)pyrene alone decreased the number of adherent type II pneumocytes, but did not alter surfactant amounts because of an increased production of surfactant per cell. Type II pneumocytes seem to adjust surfactant production dependent upon the number of type II pneumocytes to produce it and vitamin A or E enhance cell attachment in the presence of the smoke toxins. 相似文献
3.
YOICHI OHAMA YUKINO ITAKURA NORIHISA KOYAMA HIDESHI EGUCHI YUNOSUKE OGAWA 《Pediatrics international》1994,36(3):236-238
Meconium aspiration syndrome (MAS) is a frequent cause of respiratory distress in neonates. Recent reports have suggested that surfactant dysfunction contributes to the pathophysiology of MAS and surfactant therapy improves oxygenation of infants with MAS. We evaluated the effect of bronchial lavage with surfactant solution in a rabbit model of meconium aspiration. All animals were given 5 mL/kg of a 20% slurry of human meconium into the endotracheal tube and mechanically ventilated. The animals were then divided into saline lavage (n = 5) or surfactant lavage (n = 5). Lavage was performed an hour after meconium instillation. After the lavage the total amount of meconium recovered was measured. Blood gas was monitored during the experiment. The amount of meconium recovered by saline lavage was 14%, and by surfactant lavage was 57%. The surfactant group had a significant improvement in gas exchange, whereas the saline group had no improvement. It was concluded that the lavage with surfactant solution effectively washed out meconium and improved gas exchange in rabbit model of MAS. 相似文献
4.
根据胜利黄岛原油的性质,在筛选了几十种破乳剂的基础上,选择了酚醛树脂和环氧环烷,环氧乙烷的嵌段共聚物作破乳剂,探讨了破乳剂组成对原油脱水,脱盐以及界面张力的影响,通过静态脱盐,脱水试验,得到了适合黄岛原油的最佳破乳剂组成。 相似文献
5.
表面活性剂在光度分析中已经有了广泛的应用,不论是在水溶液中测定的胶束增溶光度法还是在有机溶剂中测定的胶束萃取光度法中,表面活性剂的加入都具有明显的增溶、增敏和增稳作用,它能直接影响显色反应的速度、平衡位置以及配合物的构型,能改变溶剂的 相似文献
6.
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8.
C. F. POETS A. ARNING W. BERNHARD C. ACEVEDO & H. VON DER HARDT 《European journal of clinical investigation》1997,27(4):293-298
Alveolar surfactant is well known for its ability to reduce minimal surface tension at the alveolar air–liquid interface to values below 5 mN m?1. In addition, it has been suggested that surfactant is also present in the airways, particularly in the perinatal period. We isolated surfactant from pharyngeal aspirates obtained from 33 neonates immediately after delivery and analysed it for both phospholipid (PL) composition and surface tension function. PL classes and phosphatidylcholine (PC) molecular species were determined by normal and reversed-phase high-performance liquid chromatography (HPLC), respectively. Static and dynamic surface properties of the surfactant were studied in a pulsating bubble surfactometer. Sample volume was 1.3 ± 0.5 mL (mean ± SD) with a total amount of 2.5 ± 1.3 μmol of PL and a concentration of 2.1 ± 1.0 μmol mL?1 PL. HPLC analyses of PL classes revealed a composition identical with surfactant prepared from alveolar washes, i.e. PC 83.6 ± 2.1%, sphingomyelin 1.4 ± 0.5%, phosphatidylglycerol 8.1 ± 1.6%, phosphatidylethanolamine 2.1 ± 0.5% and phosphatidylinositol 2.6 ± 1.1%. Thin-layer chromatography showed almost identical results but was more time-consuming and needed more material for analysis. Analysis of PC molecular species revealed a composition typical of human alveolar surfactant with 54.7 ± 3.9% dipalmitoyl PC, 10.3 ± 1.9% palmitoyloleoyl PC and 9.1 ± 1.5% palmitoylmyristoyl PC. Minimal surface tension fell to values below 5 mN m?1 within 5 min of cycling in all subjects. The methods used in this study allowed for complete PL and surface tension analyses of surfactant obtained during routine pharyngeal suctioning after delivery at term. Whether they are also applicable to preterm neonates with respiratory distress remains to be determined. 相似文献
9.
目的:观察地塞米松对冷藏离体肺表面活性物质和顺应性的影响.方法:32只家兔肺随机均分为对照组、地塞米松冷藏(4℃)保存24h、72h、120h3个组.对照组:测定室温条件下的肺表面活性物质及顺应性.冷藏组:肺离体后立即置于含有地塞米松台式液中冷藏,在相应时间取出肺,室温条件下复温后,置入生理盐水中,测定肺表面活性物质,并测定注气(生理盐水)和抽气(生理盐水)过程中,肺容积在10ml、20ml、30ml时的肺顺应性.结果:冷藏24h组注水、抽水;72h组肺容积在10ml、20ml抽气、冷藏120h组在肺容积为10ml、20ml抽气的肺顺应性同对照组比较,差异无显著性(P>0.05).其余各组、项与对照组比较差异具有显著性(P<0.05),伴有表面活性物质的减少.结论:地塞米松冷藏离体肺顺应性增大,其影响程度随冷藏时间的延长而增加,同时伴有肺表面活性物质的减少. 相似文献
10.
参附注射液对肺组织表面活性物质合成的影响 总被引:1,自引:0,他引:1
目的 :探讨参附注射液对肺表面活性物质合成 (PS)的影响。方法 :采用无血清成年大鼠肺组织培养 ,液体闪烁计数测定肺组织 [3H]胆碱掺入量 ,化学定磷法及薄层层析法测定总磷脂 (TPL)及磷脂酰胆碱 (PC)。结果 :参附注射液以剂量依赖方式促进肺组织 [3H]胆碱的掺入 ,并提高肺组织总磷脂、PC的含量及PC/TPL比值 ,该效应可被蛋白激酶C(PKC)抑制剂H7和钙调蛋白抑制剂W7阻断。人参总皂甙及单体Rb1,Rg1均可促进 [3H]胆碱的掺入。结论 :参附注射液可以促进PS的合成 ,其效应有赖于PKC及钙调蛋白的介导 ,人参皂甙是参附注射液促PS合成的有效成分之一。 相似文献