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31.
32.
经皮冠状动脉介入治疗已成为治疗冠心病的重要手段之一,但术后再狭窄仍是介入心脏病学面临的难题。现论述雷帕霉素的一般药理特性和雷帕霉素洗脱支架预防再狭窄的基础研究、临床试验等方面的研究进展。并探讨了可能存在的问题。 相似文献
33.
犬烟雾吸入性损伤早期肺洗出液灌注大鼠肺所致损伤的研究 总被引:2,自引:0,他引:2
目的 研究犬烟雾吸入性损伤早期肺洗出液的生物学活性。 方法 获取犬急性烟雾吸入性损伤早期肺洗出液及正常犬肺洗出液。将Wistar大鼠随机分为A(2 8只 )、B(2 9只 )、C(37只 )组 ,每组各取 7只不作处理作为正常对照 ,其余大鼠肺部作如下处理 :A组注入等渗盐水 ,B组注入正常犬肺洗出液 ,C组注入致伤犬肺洗出液。处死各组中正常对照大鼠 ,并于灌注后 4、12、2 4h处死灌注大鼠 ,观察各组大鼠处死前的存活情况、处死后双肺大体变化及组织病理学改变。检测肺组织匀浆中 6 酮 前列腺素F1α/血栓素B2 (PGF1α/TXB2 )、肿瘤坏死因子α(TNF α)、髓过氧化物酶 (MPO)含量及肺毛细血管通透性。 结果 A、B组大鼠处死前均存活 ,C组大鼠非处死死亡 9只。犬吸入性损伤早期肺洗出液可引起大鼠肺产生类似于烟雾吸入性损伤样的病理变化。A、B组大鼠灌注后肺组织PGF1α/TXB2 均有升高倾向 ;C组大鼠灌注后PGF1α/TXB2 逐渐降低 (P <0.0 1),A、B组灌注后肺组织TNF α、MPO含量均无明显变化 (P >0.0 5 ),C组灌注后 4h肺组织TNF α、MPO含量显著增加 ,分别为 (1.0 2± 0 .0 4 )ng/ml、(1.0 1± 0.0 9)U/g肺组织湿重 ,随后下降 (P <0.0 5~ 0.0 1)。肺灌注后4hC组大鼠肺组织毛细血管通透性高于A、B组 (P <0.0 1)。结论 犬 相似文献
34.
Unidirectional fluxes of 45Ca, 36Cl, and of [3H]mannitol from blood into the sciatic nerve and cerebral cortex were determined from 5- and 15-min uptakes of these tracers after an intravenous (i.v.) bolus injection in awake rats. Rats were fed diets for 8 wk, that had either a low (0.01% wt/wt), normal (0.67%), or high (3%) Ca content. Plasma [Ca] was 32% less and 11% more in rats fed low (LOCA) and high Ca diets (HICA), respectively, than in rats fed a normal Ca diet (CONT). The mean permeability-surface area product (PA) of 45Ca at the blood-nerve barrier was about eightfold higher than at the blood-brain barrier in the same animals and did not differ significantly between groups (greater than 0.05). Mean PA ratios of 45Ca/36Cl for the blood-nerve and blood-brain barriers in CONT rats, 0.52 +/- 0.04 and 0.40 +/- 0.02, respectively, were not significantly different from corresponding ratios in LOCA and HICA groups, and corresponded to the aqueous limiting diffusion ratio (0.45). Our results show no evidence for concentration-dependent transport of Ca over a plasma [Ca] range of 0.8-1.4 mmol/liter at the blood-nerve barrier of the rat peripheral nerve, and suggest that Ca and Cl exchange slowly between nerve and blood via paracellular pathways. 相似文献
35.
Albert B. Zajko M.D. Klaus M. Bron William L. Campbell 《Cardiovascular and interventional radiology》1987,10(1):28-31
Biliary obstruction and multiple hepatic abscesses occurred in a patient after ligation of a segmental branch of the right
hepatic duct. The patient was successfully managed by transhepatic biliary drainage and balloon dilatation of an internal
fistula that developed between the ligated duct and a Roux limb of jejunum. Internal biliary fistulas may be dilated using
interventioanl radiologic techniques to permit nonobstructed bile flow. Implications for the nonsurgical treatment' of biliary
strictures are discussed. 相似文献
36.
超声引导下经皮经肝胆管穿刺置管引流在梗阻性黄疸病人中的应用 总被引:1,自引:0,他引:1
目的 评价超声引导下经皮经肝穿刺胆管置管引流 (UPTBD)对梗阻性黄疸病人的治疗价值。方法 对 1995年 1月至 2 0 0 2年 7月期间的 4 17例梗阻性黄疸病人进行 4 97次UPTBD治疗 ,并回顾总结他们的临床资料。结果 接受PTBD治疗共有 4 17例 (5 1例病人进行了两个胆管枝的PTBD) ,穿刺成功率达 93.2 % (4 36 / 4 6 8) ,32例首次穿刺失败的病人有 2 9例进行了第二次穿刺置管 ,全部成功。发生胆汁漏 /胆汁性腹膜炎 9例 ,胆道出血 8例 ,感染性休克 1例 ,无腹腔出血、后腹膜血肿、气胸等其他并发症。对 6 4例置管引流患者进行肝功能检测 ,与穿刺前相比 ,引流后 1周和 3周检测病人血清胆红素、转氨酶均显著下降。结论 UPTBD是一项姑息性治疗梗阻性黄疸的快捷、安全、有效的方法 相似文献
37.
目的 探讨微创经皮肾镜取石术治疗上尿路结石的有效性和安全性.方法上尿路结石患者368例,平均年龄57岁.其中输尿管上段结石116例,结石大小(2.1±0.8)cm;肾结石252例,结石大小(4.6±1.4)cm,其中非鹿角形结石190例,结石大小(3.2±1.1)cm,鹿角形结石62例,结石大小(7.6±1.6)cm.均采用微创经皮肾穿刺,输尿管镜下气压弹道或联合钬激光碎石治疗,对结石清除率和并发症等进行统计分析.结果 368例患者中单通道取石356例(96.7%),双通道12例(3.3%).一期取石344例(93.5%),二期取石24例(6.5%).总结石取净率为88.6%(326/368).平均手术时间73 min.一期取净结石者住院时间4~8 d,平均6 d.术后发热14例(3.8%);输血5例(1.4%);2例肾结石术后出血严重者经输血及超选择性肾动脉栓塞后治愈.结论 微创经皮肾镜取石术损伤小、住院时间短、术中出血及并发症少、结石清除率高、可重复取石,是治疗上尿路结石有效的微创手段. 相似文献
38.
Peter Gode Göran Lindbergh Göran Sundholm 《Journal of electroanalytical chemistry (Lausanne, Switzerland)》2002,518(2):115-122
A new method to study permeation of gases in proton conducting membranes using a cylindrical microelectrode is presented. The focus of this work was to develop an in-situ method to study transport properties of hydrogen and oxygen close to real fuel cell operating conditions. The gas permeability is strongly affected by the change of water content in the membrane and it is therefore of advantage that, by using this method, measurements can be carried out over a wide range of relative humidities. The numerical method makes it possible to separate the diffusion coefficient and the concentration of dissolved gas in the membrane and also allows kinetic limitations to be taken into account. Chronoamperometric measurements on Nafion® 117 were successfully evaluated numerically. Experiments at temperatures of 25 and 60 °C with respect to oxygen permeation and at 60 °C for hydrogen permeation at relative humidities in the range 30–94% are presented. The reproducibility of data was excellent when measuring with different microelectrodes on the same membrane sample, but differed when measuring on different samples. In general, the permeability increases with increasing temperature and relative humidity. 相似文献
39.
Man-Hong Jim Hee-Hwa Ho Annie On-On Chan Wing-Hing Chow 《Catheterization and cardiovascular interventions》2007,69(7):969-975
BACKGROUND: Sleeve technique is a modified version of crush technique. It is specifically designed to increase the success rate of final kissing balloon inflation, which used to be a major limitation of the latter. OBJECTIVES: The aim of this study was to examine the feasibility, safety, and early clinical outcomes of sleeve technique in stenting different types (de novo, in-stent restenotic or in-stent bifurcation) of coronary bifurcation lesions at different locations. METHODS: From August 2005 to May 2006, 41 consecutive patients with symptomatic, nonleft-main coronary bifurcation stenoses of diameter narrowing >or=50% were treated with two-stent strategy, using sleeve technique. RESULTS: The mean age was 63.6 +/- 11.6 years with male predominance (70.7%). High prevalence of diabetes mellitus (31.7%), total occlusion (22.0%), and multi-vessel disease (65.9%) was observed in this cohort. Intravenous abciximab was given in 35 (85.4%) patients. Final kissing balloon inflation was successfully performed in all patients. The minimal luminal diameter in main vessel and side branch was increased from 0.97 +/- 0.53 mm and 0.81 +/- 0.45 mm to 2.76 +/- 0.34 mm and 2.22 +/- 0.35 mm, respectively. The mean procedure time was only 66.6 +/- 24.6 min. There was one (2.4%) case of subacute stent thrombosis presented as non-Q-wave myocardial infarction at day 3 postprocedure. The resultant in-hospital and 30-day major adverse cardiac event rate were both 2.4%. CONCLUSIONS: Sleeve technique is a feasible and efficient approach in stenting of coronary bifurcation stenoses. 相似文献
40.
Stratum corneum architecture, metabolic activity and interactivity with subjacent cell layers 总被引:3,自引:0,他引:3
Peter M. Elias 《Experimental dermatology》1996,5(4):191-201