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71.
BACKGROUND: This experimental study sought to determine whether heparin-bonding of intraaortic balloons (IAB) would decrease the incidence of arterial thrombosis in the absence of systemic heparinization. METHODS: In 25 adult pigs, a 9F, 40-mL IAB was inserted into the femoral artery and positioned just below the takeoff of the left subclavian artery for 9 hours. Five animals received systemic heparin, 10 animals had no heparin, and another 10 animals received no heparin but the IAB was heparin-bonded (Duraflo II). Thrombus formation was assessed using a numerical scoring system (0 = no thrombosis to 3 = thrombus >5 cm or evidence of luminal compromise). RESULTS: Animals receiving heparin and heparin-bonded IAB had no thrombus formation around the IAB (mean +/- SE; 0 +/- 0.00 heparin versus 1.55 +/- 0.29 no heparin versus 0 +/- 0.00 heparin-bonded; p < 0.005), at the insertion site (0 +/- 0.00 heparin versus 1.55 +/- 0.29 no heparin versus 0 +/- 0.0 heparin-bonded; p < 0.005), and in the distal femoral artery (0 +/- 0.00 heparin versus 2.00 +/- 0.23 no heparin versus 0 +/- 0.00 heparin-bonded; p < 0.005). CONCLUSIONS: Heparin-bonding of the IAB significantly decreases thrombus formation in the absence of systemic heparinization. 相似文献
72.
Lazar HL Bao Y Lancaster D Shapira OM Aldea GS Shemin RJ 《The Annals of thoracic surgery》1999,68(5):1644-1647
BACKGROUND: This study was undertaken to determine the impact of the use and availability of coronary stents on outcomes in patients requiring emergent coronary artery bypass graft (CABG) surgery following a failed percutaneous transluminal coronary angioplasty (PTCA). METHODS: Patients were divided into two groups based on the year of their CABG for a failed PTCA and the availability of stents: group 1, 1992 to 1994, stents not available (n = 34); and group 2, 1995 to 1997, stents available (n = 26). RESULTS: CABG patients in the group where stents were not available were more likely to have had an abrupt coronary occlusion (26 of 34 versus 3 of 26; p < 0.0001) and less likely to have had a dissection (8 of 34 versus 23 of 26; p < 0.0001) as their indication for emergent CABG. Patients in the stent era had a lower incidence of perioperative myocardial infarction (5 of 26 versus 17 of 34; p < 0.01) and a decreased mortality rate (0 of 26 versus 6 of 34; p < 0.03). In the 9 patients where stents were employed, patency of the lumen was restored in 8 patients and there was only 1 myocardial infarction. CONCLUSIONS: Stents have had a favorable impact on patients requiring an emergent CABG following a failed PTCA. 相似文献
73.
Regulation of the angiotensin type-1 receptor by antisense oligonucleotides occurs through an RNase H-type mechanism 总被引:6,自引:0,他引:6
Multiple, diverse sites in the coding region of the angiotensin type-1 receptor mRNA were targeted with 2'-deoxyribonucleotide antisense oligonucleotides (ONs). The uptake of 1 microM concentration of these ONs into Chinese hamster ovary cells was facilitated by the use of cationic liposomes. The antisense sequences reduced binding of 125I-angiotensin II by 57-73%, while mismatch ONs and reverse sequence ONs produced little reduction in receptor binding. These reductions in AT1 receptor binding were accompanied by comparable decreases in AT1 receptor mRNA levels. Furthermore, mRNA cleavage fragments corresponding in size to 3'-cleavage fragments were observed with two of the antisense ONs, consistent with the involvement of an RNase H-type enzyme. When 2'-methoxyribonucleotide analogs of these same sequences were tested, AT1 receptor mRNA levels were unchanged even though small reductions in AngII binding were observed. Antisense effects seen with these 2'-methoxyribonucleotide sequences may have arisen through a translational arrest mechanism. Direct comparisons between 2'-deoxyribonucleotide analogs and their 2'-methoxyribonucleotide counterparts show that antisense effects are significantly larger when they are mediated through an RNase H-type mechanism. 2'-methoxyribonucleotide sequences were most effective when they were directed against the translation initiation codon. 相似文献
74.
Glutathione (GSH) is known to play an important role in regulating oxidative damage to cells. The present study was initiated to examine the effect of exogenous GSH on oxidative injury in a retinal Müller cell line and to characterize GSH transport in these cells. Rat Müller cells (rMC-1) were incubated with varying concentrations of t-butylhydroperoxide (t-BHP) to induce oxidative stress, and cell viability was measured after addition of GSH. In other studies, kinetics of GSH uptake and Na+-dependency were examined by incubating cells with35S-GSH in Na+-containing and Na+-free buffers. GSH uptake was studied with GSH at concentrations varying from 0. 05-10 m m in NaCl buffer. In the presence of sodium, extracellular GSH provided protection against t-BHP-induced oxidant injury to rMC-1 cells; in contrast, the amino acid precursors of GSH did not have any effect on cell viability. GSH was taken up by rMC-1 cells in a concentration- and sodium-dependent manner. Kinetic studies revealed both a high affinity (Km approximately 0.31 m m) and low affinity Km( approximately 4.2 m m) component. Furthermore, GSH depletion had no significant effect on the rate of GSH uptake. The results show that physiological concentrations of GSH can protect Müller cells from oxidative injury. Both Na+-dependent and Na+-independent transport systems for GSH exist in Müller cells, and the Na+-dependent GSH transporter may be involved in the protective role of GSH. 相似文献
75.
The author used smear from Stensen's duct aspiration to observe exfoliated cytology in order to help diagnosis of early mumps.According to the smears from 100 cases of mumps and other 50 cases of bacteria parotitis and/or normal parotid as contro,the author revealed that if there are a lot of ductal epithelial cells,monocytes and polynuclear cells,monocytes and polynuclear phagocytes at same time,it could give diagnosis "Mumps" to that patient.In control group,it is unable to observe those three kind cells at same time.The author also discussed the mechanism of how would these three kind cells appear in mumps in accordance with references. 相似文献
76.
目的:评价激光虹膜切除治疗闭角型青光眼临床疗效。方法:应用Nd:YAG激光于上方或下方作周边虹膜切除。结果:107例122眼闭角型青光眼术后经过2—106月随访观察,成功115眼,失败7眼。结论:激光虹膜切除术治疗闭角型青光眼安全、有效。 相似文献
77.
78.
通关利窍针法治疗中风致假性延髓麻痹临床观察 总被引:8,自引:0,他引:8
目的 观察通关利窍针法治疗中风致假性延髓麻痹的疗效。方法 将 10 0例患者随机分为治疗组和对照组各 5 0例 ,治疗组采用通关利窍针法 ,对照组采用康复训练法 ,均 14次为 1个疗程 ,疗程间休息 3日 ,2个疗程后评定疗效。结果 治疗组总有效率 96 .4 % ,对照组 2 4 % ,两组差异有显著性意义 (P<0 .0 5 ) ,治疗组疗效和年龄、病程、病情轻重有关。结论 通关利窍针法治疗中风后假性延髓麻痹优于康复训练法 相似文献
79.
针刺对吗啡戒断大鼠脑组织一氧化氮合酶基因表达的影响 总被引:5,自引:0,他引:5
目的 :观察针刺对吗啡戒断大鼠脑组织神经元一氧化氮合酶基因 (nNOSmRNA)表达的影响 ,探讨针刺改善戒断症状的分子生物学机理。方法 :建立大鼠吗啡自然戒断模型 ,运用逆转录聚合酶链反应 (RT PCR)测定戒断大鼠脑组织nNOSmRNA的表达。观察戒断后 ,针刺“足三里”和一氧化氮合酶 (NOS)抑制剂L N 硝基精氨酸 (L NAME)对吗啡戒断大鼠戒断症状和脑组织nNOSmRNA表达的影响。结果 :戒断组nNOSmRNA表达增加 ,针刺组和L NAME组nNOSmRNA表达比戒断组减少。针刺组戒断积分比戒断组少 ,组间差异显著 (P <0 .0 1 )。结论 :针刺“足三里”穴具有抑制吗啡戒断大鼠脑组织nNOSmRNA表达的作用 ,提示这可能是针刺改善吗啡戒断症状的一个重要机制。 相似文献
80.
目的 :筛选和克隆胃印戒细胞癌与正常胃黏膜细胞差异表达基因片段。方法 :采用mRNA差异显示法 (mRNAdifferentialdisplayPCR ,DD PCR) ,对比胃印戒细胞癌组织与正常胃黏膜组织mRNA的表达差异 ,克隆胃印戒细胞癌差异片段 ,经过RNA的斑点杂交、测序以及序列分析和同源性比较。结果 :胃印戒细胞癌与正常胃黏膜中存在明显的基因表达差异 ,发现与胃癌相关的差异表达条带 16条 ,其中 7条为缺失表达条带 ,9条为过度表达条带。对其中 4条差异表达条带进行克隆、测序 ,经序列分析及同源性比较和RNA的斑点杂交 ,表明确认其中 1条为GenBank/BLAST中尚未收录的片段。结论 :胃印戒细胞癌的mRNA差异显示证明 ,该EST序列可能在胃癌的发生发展中具有一定作用 相似文献