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1.
《Journal of vascular and interventional radiology : JVIR》2020,31(6):986-992
PurposeTo assess the feasibility, safety, and efficacy of balloon-assisted delivery of ethylene vinyl alcohol copolymer (EVOH) for a range of peripheral arterial applications.Materials and MethodsSix academic medical centers entered retrospective data on 46 consecutive patients (27 men, 19 women; ages, 11–94 y; mean age, 50.3 y) who underwent 60 balloon-assisted EVOH procedures. The cohort was restricted to procedures involving peripheral, nonneural arteries 1–5.5 mm in diameter. Clinical indications included a wide range of vascular pathologic conditions (most commonly arteriovenous malformations [n = 20], renal angiomyolipomas [n = 8], and acute hemorrhage [n = 9]) and targeted visceral and musculoskeletal peripheral arteries. Data collected included sex, age, clinical indication, arterial pathology, arteries embolized, type of occlusion balloon microcatheter, type and concentration of EVOH agent, effectiveness as an embolic backstop, vessels protected, adequacy of EVOH cast penetration, catheter extraction, nontarget embolization, and complications.ResultsBalloon occlusion prevented EVOH reflux in 59 of 60 procedures (98.3%). Nontarget EVOH embolization occurred in 2 procedures (3.3%). Adequate EVOH cast penetration and complete filling of the target pathologic structure were seen in 57 of 60 procedures (95%). Balloon deflation and uneventful extraction occurred in all procedures; small EVOH fragments detached into target arteries in 2 cases. One major (1.7%) and 2 minor (3.3%) complications occurred.ConclusionsBalloon-assisted EVOH embolization of peripheral arteries is feasible, safe, effective, and versatile. The primary advantage of balloon-assisted EVOH embolization is the ability to apply more injection pressure to advance the EVOH cast assertively into the pathologic structure(s). 相似文献
2.
Zia Hossein Ma Joseph K. H. O'Donnell John P. Luzzi Louis A. 《Pharmaceutical research》1991,8(4):502-504
Dimethyl isosorbide (DMI), which is currently under investigation for its potential use as a pharmaceutical vehicle and drug permeation enhancer, is a water-miscible liquid with relatively low viscosity. The solubilization behavior of DMI as a cosolvent for nonpolar drugs was characterized via dielectric constant measurements of binary solvent systems containing DMI and either water, propylene glycol (PG), or polyethylene glycol (PEG). Evidence from the dielectric constant profiles and NMR studies suggest that DMI undergoes complexation with water and PG, but not with PEG, through hydrogen bonding interactions. The solvent complexation exhibited a major effect on the solubilities of prednisone, dexamethasone, and prednisolone in the mixed solvent systems. Maximum solubility of each drug was found to occur near a DMI/water or DMI/PG concentration ratio of 1:2. In the DMI–PEG mixed system, while there is no apparent interaction between DMI and PEG molecules, the solubility of prednisone was found to increase with decreasing dielectric constant. 相似文献
3.
汽油添加剂甲基叔丁基醚的毒性研究 总被引:1,自引:1,他引:0
目的 通过研究汽油添加剂甲基叔丁基醚 (MTBE)对小鼠体内谷胱甘肽 (GSH)、谷胱甘肽过氧化物酶 (GSH -Px)活性的改变以及骨髓微核、精子畸变率的影响 ,了解汽油添加剂甲基叔丁基醚的毒性。方法 40只健康昆明种成年小鼠 ,体重 3 3 .3± 6 .9g ,随机分为 4组。灌胃染毒 ,染毒剂量分别为1 6 0 0、40 0、1 0 0和 0mg kg。每天 1次 ,每周 5天 ,共计 40天。结果 MTBE染毒各组小鼠体重轻度降低 ,染毒组全血及肝组织匀浆中GSH在低剂量染毒时增高 ,而高剂量时表现为降低 ,与对照组比较差异有显著性 (P <0 .0 5 ) ;GSH -Px活性明显减低 ,染毒高剂量组与对照组比较差异有高度显著性 (P <0 .0 1 ) ;骨髓嗜多染红细胞微核及精子畸变率增高 ,与对照组比较明显增高 ,差异有显著性 (P <0 .0 5 )。结论 MTBE对昆明小鼠具有一定毒性 ,可降低全血及肝脏组织中GSH -Px活性 ,低剂量时可增加全血及肝脏组织中GSH含量 ,而高剂量可降低其含量。MTBE能使骨髓微核率、精子畸形率明显增高 ,提示MTBE具有潜在的遗传毒性。 相似文献
4.
通过溴化聚苯醚和格利雅试剂反应,将不饱和基团烯丙基引入聚苯醚中实现其热固性改性,由^1H-NMR和FTIR进行结构表征。确定了烯丙化聚苯醚的固化工艺,并对其固化产物性能进行测试。结果表明:按合成新工艺制备的热固性聚苯醚,其固化产物具有优异的介电性能(低介电常数、低介电损耗因子),良好的耐溶剂性能和低吸湿性。 相似文献
5.
目的 分析国产光敏剂血卟啉单甲醚(HMME)在不同溶液中光漂白反应动力学规律,加深对光漂白反应复杂反应过程的理解,并为HMME-PDT治疗微血管病变的数学建模研究提供实验依据和参数。
方法 根据光化学反应动力学原理,从理论上推导出在单纯溶液和复杂溶液(含可被光氧化的底物)中,单态氧介导的光漂白反应动力学方程,通过对实验测定的漂白数据(不同时间点的HMME浓度)进行拟合,进一步验证理论推导出光漂白反应动力学方程。
结果 HMME在单一溶液体系(PBS、DMSO)中的光漂白符合1级反应动力学过程,在含底物的复杂体系(白蛋白缓冲液、细胞悬液)中符合2级反应动力学过程。
结论 HMME在不同溶液体系中的光漂白遵循不同的反应动力学规律。根据化学反应动力学原理进行光漂白等复杂光化学反应过程的数学模拟是可行的,并有利于对复杂光化学反应过程的深入理解。 相似文献
6.
Expression of mRNAs encoding the erythroid-specific delta-aminolevulinate synthase (ALAS-E) and the nonspecific delta-aminolevulinate synthase (ALAS-N) were examined in murine Friend virus-transformed erythroleukemia (MEL) cells using nonradioactive in situ hybridization. Following dimethyl sulfoxide (DMSO) treatment, ALAS-E mRNA increased markedly, while ALAS-N mRNA did not increase in wild-type MEL cells. In contrast, in a DMSO-resistant clone of MEL cells, ALAS-E was not detectable before and after DMSO treatment. These findings suggest that ALAS-E and ALAS-N mRNAs are under separate controls and that the expression of ALAS-E mRNA is a critical event in erythroid differentiation. 相似文献
7.
甲基叔丁基醚无铅汽油肾脏毒性的实验研究 总被引:6,自引:0,他引:6
目的:了解甲基叔丁基醚(MTBE)无铅汽油对肾脏的毒性及毒作用机制。方法:昆明种小鼠经呼吸道静式染毒,MTBE无铅汽油22.9、11.4及2.3g/m^3每天一次,连续2h,共22d亚急性染毒。日立-7150型全自动生化仪检测血清中尿素氮(BUN)、肌酐(Cr)含量;肾组织均浆中丙二醛(MDA)和超氧化物歧化酶(SOD)含量分别用荧光法,邻苯三酚自氧化固定时间法测定;电镜观察肾皮质区超微结构的变化,结果:22.9g/m^3染毒组雌性小鼠血清中BUN含量与阴性对照组间比较差异有显著性(P<0.05);电镜观察到22.9g/m^3染色毒对照组雌雄性小鼠的肾小球基底膜,肾小管细胞线粒体及绒毛均未见显著异常改变。结论:MTBE无铅汽油对肾小球的滤过功能有一定的影响,雌性小鼠可能更为敏感。 相似文献
8.
Dr. Juergen Pauletzki MD Joseph Holl MD Michael Sackmann MD Michael Neubrand MD Ulrich Klueppelberg MD Tilman Sauerbruch MD Gustav Paumgartner MD 《Digestive diseases and sciences》1995,40(8):1775-1781
To determine the rate and characteristics of gallstone recurrence after direct contact dissolution with methyltert-butyl ether, 60 consecutive patients were followed for up to 4.5 years (median 2.2 years) after complete disappearance of all stone residues and debris and cessation of adjuvant bile acid therapy. Initial gallstones had been multiple in all but four patients. Twenty-eight of the 60 patients developed recurrent gallstones. The cumulative risk of gallstone recurrence (actuarial analysis) was 23±6%, 34±7%, 55±8%, and 70±9% at one, two, three, and four years, respectively. The recurrent stones were usually multiple and small (6±4 mm). Gallstone recurrence was associated with recurrent biliary pain in two patients, one of whom developed acute cholecystitis. Recurrent stones were cleared completely by bile acid medication with or without shock-wave lithotripsy in 61±15% of patients at one year (actuarial analysis). In conclusion, gallstone recurrence after successful contact dissolution of multiple stones with methyltert-butyl ether has to be expected in a high percentage of patients. Most patients, however, remain free of biliary pain during long-term follow-up. 相似文献
9.
Tissue distribution metabolism and excretion of 2,2′,4,4′, 5-pentachlorodiphenyl ether in the rat 总被引:1,自引:0,他引:1
E. Komsta I. Chu D. C. Villeneuve F. M. Benoit D. Murdoch 《Archives of toxicology》1988,62(4):258-262
The tissue distribution, metabolism and excretion of 14C-2,2,4,4,5-pentachlorodiphenyl ether (PCDE) were studied in the rat. Radioactivity was distributed in all tissues examined, with the highest concentrations being found in the fat followed by the skin, liver, kidney and muscle. Most of the radioactivity found in the tissues was due to unchanged PCDE. Decay of PCDE in the blood was fitted to a four-compartment pharmacokinetic model, and the last compartment had a half-life of 5.8 days. A total of 55% and 1.3% of an orally administered dose was excreted in feces and urine, respectively, in 7 days. More than 64% of the fecal radioactivity was due to unchanged PCDE, while hydroxylated PCDE accounted for 23%. 相似文献
10.