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81.
Abstract: Adequate venous access is an essential component of therapeutic plasma exchange (TPEX). The simplest kind of venous access is venipuncture of antecubital veins, but this technique may be limited by venous size or scarring following the procedure, requiring the placement of a specialized vascular access device (VAD). VADs provide reliable central venous access and may remain in place for several weeks or months, depending on the VAD and the venous site chosen. Their use, however, is potentially limited by the risk of complications. We discuss indications for insertion, choice of catheter and access site, and complications of VAD placement for TPEX. 相似文献
82.
83.
ADM对LNNA诱导的高血压心肌肥大的作用及机制探讨 总被引:1,自引:0,他引:1
本工作在LNNA经慢性NO封闭诱导的大鼠高血压心肌肥大模型上研究了ADM对其心肌肥大和M5LV钠一钙交换功能损伤的作用。结果:一、较之对照组,LNNA组MAO和LVI分别增加57.4%和18。0%(P<0.01).其MSLV经钠-钙交换蛋白的钙摄取则明显降低(P<0.01或0.05):二.ADM组的MAP和LVI则分别较LNNA组降低19.6%和11.3%,而其MSLV的钙摄取则高于LNNA组(P<0.05);三、对照组、LNNA组和ADM组钠-钙交换蛋白摄取钙的Km值分别为7.51.7.04和7.57uM,而Vmax则分别为6.38,4.32和5.45nmol/。mgpr/min。表明:ADM能拮抗LNNA诱导的高血压心肌肥大和减轻其MSllV钠-钙交换功能的损伤,并且后者可能是ADM拮抗心肌肥大的机制之一。揭示内源性ADM的诱导和外源性给予ADM可能有预防和/或延缓高血压心肌肥大发生发展的作用。 相似文献
84.
Six patients with prolonged acute courses of thrombotic microangiopathy are reviewed. These patients had in common courses of acute disease requiring plasma support for more than 3 months, with subsequent complete remission. Plasma support requirements may be prodigious, and the acute course may require more than 100 plasma exchanges before a stable remission is achieved. These patients appear to represent a subset of thrombotic microangiopathy distinct from the more common acute T.T.P. course, which resolves in 3–6 weeks, and the chronic relapsing pattern, which may have a short or prolonged acute course. © 1992 Wiley-Liss, Inc. 相似文献
85.
Kalpana Agarwal Anita Mukherjee Archana Sharma Ramesh Sharma Kuldip Raj Bhardwaj Soumitra Sen 《Environmental and molecular mutagenesis》1992,19(4):323-326
Fenfluramine, an amphetamine derivative used in the treatment of obesity, has been evaluated in vivo in the bone marrow cells of Swiss albino mice using two cytogenetic endpoints for assessing its genotoxic and clastogenic potentials. Concentrations of 0.75, 1.5, 3.0, and 5.0 mg/kg b.w. were administered orally for the study of sister chromatid exchange frequencies and chromosome aberrations (CA). SCE frequencies showed a positive dose response; 1.5 mg/kg being the minimum effective concentration. Fen caused a prolongation of cell cycle at all concentrations. Except for the minimum therapeutic dose (0.75 mg), all other doses (1.5, 3.0, and 5.0 mg) showed a significant increase in the percentage of damaged cells over that of the vehicle control. The degree of clastogenicity was directly proportional to the dosage used and inversely related with the duration of treatment. A gradual reduction of the clastogenic potential was observed after 12 and 24 hr of exposure, indicating that the maximum effect occurs at the middle or late synthetic phase of the cell cycle. This study, probably the first detailed screening of the drug for its genotoxicity, shows that Fen is moderately clastogenic and a DNA damaging agent in vivo. 相似文献
86.
目的探讨血浆纤维蛋白原水平与急性单纯闭合颅脑损伤患者严重程度的相关意义。方法检测180例于伤后24h内到院的急性闭合颅脑损伤患者的格拉斯哥昏迷评分、纤维蛋白原含量。结果颅脑损伤病人血浆中纤维蛋白原水平明显降低;颅脑损伤越严重,血浆中纤维蛋白原含量越低,颅脑损伤越轻,纤维蛋白原含量越高,预后越好。结论血浆中纤维蛋白原水平与颅脑损伤严重程度存在明显相关性,可作为颅脑损伤严重程度的判断参考指标。 相似文献
87.
目的 为了探讨肾脏疾病患者血浆内皮素水平与肾脏疾病病情程度的关系,为肾脏疾病治疗效果的评价提供依据.方法 采用放射免疫分析(RIA)观察了77例肾脏疾病患者治疗前后血浆内皮素水平的动态变化,并与60例正常对照组比较.结果 正常对照组血浆内皮素浓度为43.1±15.2ng/L,肾脏疾病患者治疗前血浆内皮素水平为161±83.8ng/L,治疗后为97.4±52.7ng/L,均高于正常对照组(P值均<0.001).肾脏疾病治疗后内皮素水平明显下降(P<0.001),与BUN,Cr水平的下降具有一定的相关性(相关系过分别为0.54,0.55).结论血浆内皮素水平随着肾脏疾病严重程度的增加而升高,血浆内皮素水平可作为肾脏疾病治疗效果评定的指标之一 相似文献
88.
S. G. Gourlay N. L. Benowitz A. Forbes J. J. McNeil 《European journal of clinical pharmacology》1997,51(5):407-414
Objective: Interindividual variability in plasma concentrations of nicotine and its proximate metabolite, cotinine, is considerable
during smoking and transdermal nicotine treatment, even among individuals taking in nominally similar doses of nicotine. This
report explores the determinants of this variability and the utility of baseline (smoking) plasma concentrations to predict
concentrations during transdermal nicotine treatment.
Methods: Data were analysed from a smoking cessation study (n = 466), and from a pharmacokinetic study (n = 12). Multiple regression models examined the relationships of plasma concentrations to individual characteristics such
as smoking pattern, absorbed dose of nicotine, and pharmacokinetic parameters.
Results: Plasma concentrations of nicotine and cotinine were highly variable in both studies. Indirect estimates of plasma clearance
(baseline plasma concentration divided by cigarettes per day) together with other factors could account for 18 to 33% of the
variability during transdermal nicotine treatment in the smoking cessation study. In contrast, 75 to 99% was accounted for
by direct measurements of plasma clearances and systemic dose of nicotine in the pharmacokinetic study.
Conclusion: Plasma concentrations of nicotine and cotinine during transdermal nicotine treatment are poorly predicted by clinical history
or baseline plasma concentrations. This is a result of inadequate characterisation of highly variable individual pharmacokinetic
parameters and absorbed dose of nicotine. Considering the interindividual variability of plasma nicotine and cotinine concentrations
together with the lack of clinical end-points for transdermal nicotine dosing, it seems logical to investigate the utility
of a therapeutic drug monitoring approach for transdermal nicotine treatment – particularly for high dose regimens (> 22 mg
per 24 hours).
Received: 7 May 1996 / Accepted in revised form: 21 August 1996 相似文献
89.
丝裂霉素C(MMc)诱导的姐妹染色单体互换(SCE)可反映出细胞DMA损伤修复的基本过程。有关MMC诱发活体的SCE研究不多。本实验目的,就是探讨MMC诱发小白鼠骨髓细胞SCE的剂量—效应关系,并对SCE指标与染色体畸变指标,在检测机体DNA损伤上的差异作一比较研究。结果证明,MMC诱发染色体畸变能办远低于诱发SCE的能力,MMC可诱发小白鼠骨髓细胞SCE产生,SCE值随MMC剂量的增加而增加。SCE即使在低剂量诱变剂的作用下也是敏感的。 相似文献
90.
应用~(51)Cr释放试验和效靶结合试验,同时测定了正常人和胃癌病人外周血NK细胞活性与靶结合细胞数(TBC),研究了正常人及病人血浆对NK细胞功能的影响。发现正常人NK细胞活性与靶结合细胞数之间的关系呈直线正相关,但在NK活性降低的病人中靶结合细胞数却无明显改变,二者无相关性,而病人的血浆对正常人外周血NK活性则有明显的抑制作用(P<0.05),且抑制率与胃癌人NK细胞活性存有着负相关的关系,提示胃癌病人血浆具有抑制NK细胞活性的物质。 相似文献