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51.
羟乙基淀粉对内毒素感染大鼠肺部毛细血管通透性的影响   总被引:8,自引:2,他引:6  
目的 观察羟乙基淀粉(HES 200/0.5)对内毒素感染大鼠肺部毛细血管通透性的影响。方法 雄性Wistar大鼠42只随机分为对照组,内毒素组(LPS,6 mg/kg),LPS HES组(HES,3.75、7.5、15、30ml/kg)及HES对照组(30ml/kg)。分别于LPS注入后4 h检测肺组织毛细血管通透性、肺湿干重比、肺组织中性粒细胞(PMN)浸润,2 h检测肺组织核转录因子kappaB(NF-κB)水平。结果3.75 ml/kg和7.5 ml/kg HES显著降低肺毛细血管通透性、湿干重比和PMN浸润(P<0.05),3.75、7.5和15 ml/kgHES显著降低肺NF-κB活性(P<0.05)。结论较低剂量HES具有抑制感染状念下毛细血管漏的作用,这种作用的产生可能与其降低肺组织PMN浸润、抑制核转录因子NF-κB有关。  相似文献   
52.
目的 评价经皮冠状动脉腔内切割球囊成形术 (CBA)治疗初治病变和支架内再狭窄的疗效。 方法  35例冠心病病人 (初治病人 7例 ,支架内再狭窄病人 2 8例 )施行CBA。左前降支病变 2 5处 ,左回旋支病变 10处 ,右冠病变 7处。初治病变平均狭窄 (85 9± 7 2 ) % ,支架内再狭窄的平均狭窄程度是 (89 6± 8 9) %。CBA后即刻行冠脉造影评价近期手术成功率 ,随后严格的临床随访每个月 2次 ,共 6个月 ,以评价中期疗效。 结果 共使用切割球囊 4 2个 ,直径 (3 2± 0 3)mm(3 0~ 3 75mm) ,长度 10~ 15mm ,扩张压力 (72 7± 6 0 )kPa(6 0 6~ 10 10kPa) ,扩张次数 (5 0± 2 1)次 (4~ 7次 ) ,扩张时间 (2 0 3 6± 90 8)s。CBA近期手术成功率 10 0 % ,无严重冠脉闭塞等并发症。术前病变的狭窄程度为 (89 6± 8 9) % ,术后残余狭窄为 (8 8± 3 7) % (P <0 0 1)。 6个月随访未发现心绞痛复发 ,心电图和超声心动图无心肌缺血加重的证据。 结论 切割球囊不论对初治还是冠状动脉支架内再狭窄的病人 ,都是安全有效的介入治疗方法 ,其近期手术成功率高 ,中期的临床疗效确切。  相似文献   
53.
54.
Purpose. Hydrophilic and charged solutes have a lower membrane permeability which is due to a lower partition into the lipid membrane (low solubility in the membrane phase) and/or a slower transcellular diffusion coefficient. They are therefore anticipated to be absorbed through the paracellular route, which is a consequence of diffusion and a convective volume flow through the water-filled intercellular space. Methods. Two approaches have been used to investigate the mechanisms underlying the paracellular drug transport across the intestinal mucosa: (a) including water transport by exposing the apical side of the epithelium with a hypotonic solution, and (b) stimulated paracellular transport by widening of tight junction and increased water absorption as a consequence of the sodium-coupled transport of nutrients. Results. Among the first studies that recognized this fluid flux dependent transmucosal transport of drugs, was one published by Oschenfahrt & Winne in 1973 and the one by Kitazawa et al. in 1975. During the last two decades the importance of this paracellular route for drug delivery have been explored in vitro and in situ. Conclusions. The limits concerning molecular weight, shape, ionization and the effect of physiological stimulants, such as luminal concentrations of nutrients, osmolality and motility, are currently under investigation. However, recently published in vivo human data by ourselves and others indicate that the promising results obtained in vitro and in situ for various hydrophilic compounds might not be valid in quantitative aspects in humans, especially not for drugs with a molecular weight over 200.  相似文献   
55.
Purpose. This paper compares unsteady-state and steady-state methods for estimating dermal absorption or analyzing dermal absorption data. The unsteady-state method accounts for the larger absorption rates during short exposure times as well as the hydrophilic barrier which the viable epidermis presents to lipophilic chemicals. Methods. Example calculations for dermal absorption from aqueous solutions are presented for five environmentally relevant chemicals with molecular weights between 50 and 410 and log10Kow between 0.91 and 6.8: chloromethane, chloroform, chlordane, 2,3,7,8-TCDD, and dibenz(a,h)anthracene. Also, the new method is used to evaluate experimental procedures and data analyses of in vivo and in vitro permeation measurements. Results. In the five example cases, we show that the steady-state approach significantly underestimated the dermal absorption. Also, calculating permeability values from cumulative absorption data measured for exposure periods less than 18 times the stratum corneum lag time will overestimate the actual permeability. Conclusions. In general, steady-state predictions of dermal absorption will underestimate dermal absorption predictions which consider unsteady-state conditions. Permeability values calculated from data sets which include unsteady-state data will be incorrect. Strategies for analyzing in vitro diffusion cell experiments and confirming steady state are described.  相似文献   
56.
1985~1993年对43例脑血管病及脑肿瘤患者应用介入神经放射治疗方法进行了51次治疗,包括外伤性颈内动脉海绵窦瘘的球囊栓塞治疗8例;脑、脊髓血管畸形的栓塞治疗17例;各种脑肿瘤术前栓塞7例;经皮穿刺血管内成型治疗脑供血动脉狭窄3例和脑胶质瘤超选择化疗8例,效果良好,介入神经放射治疗已成为重要的临床治疗手段,是某些脑血管疾病的首选治疗方法。  相似文献   
57.
The indications, contraindications and complications of percutaneous laparoscopic cholecystectomy (PLC) were established from a group of 308 patients referred for cholecystectomy. Of the 308 patients 86% underwent PLC, 5% were commenced laparoscopically, but converted to open cholecystectomy and 9% were performed as open cholecystectomy from the outset. Complications included two bile leaks from the gall-bladder bed, one cystic duct stump leak and three retained stones. Pre-operative rather than intra-operative duct imaging was used so that common duct stones could be removed before operation. PLC is a safe procedure that has now become the standard technique for cholecystectomy.  相似文献   
58.
我们以糖皮质激素受体(GR)的竞争性拮抗剂RU38486(简称RU486)阻断大鼠体内的GR,并通过检测肺、肾组织匀浆中荧光标记白蛋白的含量,观察了烫伤后12h大鼠肺、肾血管壁通透性的变化以及阻断GR对这种变化的影响。结果显示:烫伤后12h,大鼠肺、肾组织匀浆中荧光标记白蛋白含量明显高于对照组(肺:P<0.05;肾:P<0.001);阻断GR后再烫伤大鼠,其肺、肾组织匀浆中的荧光白蛋白含量又显著高于烫伤组(P<0.05)。提示:①烫伤后12h,大鼠肺、肾血管壁通透性明显升高。②GR减少可加重烫伤所致的血管壁通透性升高,并可逆转内源性糖皮质激素(GC)稳定血管壁通透性的作用。  相似文献   
59.
Acute renal failure and acute heart failure are rare in Kawasaki disease. We experienced two patients with Kawasaki disease who presented acute renal failure and acute heart failure. These two patients gave us an important insight into the understanding of water balance and fluid therapy in Kawasaki disease. One patient showed acute prerenal failure due to fluid exudation from the intravascular to the extravascular space, and subsequent acute heart failure. The other patient showed acute heart failure caused by fluid infusion for the treatment of dehydration. It is suggested that acute renal failure could be caused by a fluid shift from the intravascular to the extravascular space in Kawasaki disease. It is also demonstrated that the reserve of cardiac function could be decreased in patients with Kawasaki disease due to myocarditis even with normal echocardiography and chest X-rays.  相似文献   
60.
本文报告经皮球囊二尖瓣成形术治疗二尖瓣狭窄12例。10例术前平均左房压为18mmHg~40mmHg(26.7±7.15mmHg),术后即刻为4mmHg~18mmHg(10.6±3.86mmHg)P<0.01。跨瓣压差术前10mmHg~40mmHg(19.6±9.05mmHg),术后为0~5mmHg(2.65±2.21mmHg)P<0.01。1例失败,1例术后发生二尖瓣关闭不全急性左心衰竭死亡。  相似文献   
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