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51.
T. Kumazawa O. Suzuki H. Seno Y. Ishikawa H. Hattori 《International journal of legal medicine》1990,103(7):479-485
Summary A simple and rapid method for isolation of seven antiepileptics (2 hydantoin, 2 oxazolidin, and 3 suximide derivatives) from urine and plasma is presented. Urine and plasma (1 ml) samples containing seven antiepileptics were mixed with distilled water (4 ml), and the sample solution was poured into a pretreated Sep-Pak C18 cartridge; this was washed with water and chloroform/methanol was passed through it to elute the antiepileptics. The eluate was mixed with isoamyl acetate and evaporated under a stream of N2. The drugs were detected by gas chromatography with fused silica capillary columns, splitless injection and flame ionization detection. Separation of the seven antiepileptics from each other and from impurities was satisfactory with the use of an SPB-1 capillary column. The detection limit for the seven antiepileptics with the present method was 0.1–1.0 g/ml urine or plasma. The recovery of the drugs from urine and plasma was more than 70% and 50%, respectively.
Offprint requests to: O. Suzuki 相似文献
52.
心脏直视手术患儿补体4基因多态性对体外循环中补体激活程度的影响 总被引:2,自引:0,他引:2
目的:研究补体4基因多态性与体外循环中补体系统激活程度和肺功能障碍之间的关系。方法:选择武汉市及周边地区在体外循环(CPB)下进行心脏直视手术的患儿156例,于术前抽血用交叉免疫电泳法进行补体4基因型分析。分别于CPB开始前,CPB结束时以及鱼精蛋白中和肝素后10min抽取动脉血样,以放免法对补体3和4活化产物C3a和C4a进行测定。同时记录肺顺应性。结果:补体4基因型AABB,AOBB,OOBB,AABO及AAOO出现频率分别为51.28%,17.95%,4.49%,19.87%及6.41%,CPB结束时C4a水平无明显升高,C3a水平显著升高。鱼精蛋白中和肝素后10min时C4a和C3a水平显著升高,以OOBB组升高最显著,其次为AOBB组;同时OOBB组肺顺应性下降最显著,其次为AOBB组,结论:体外循环由替代途径激活补体系统,鱼精蛋白-肝素复合物由经典途径激活补体系统,国人补体4基因型中,OOBB型出现的频率较白种人高,该基因型在体外循环中补体系统被激活及肺功能受损程度最严重。 相似文献
53.
目的 观察异丙酚和咪唑安定在体外循环麻醉中对术前和术中的酸碱度的影响.方法 40例先天性心脏病患者随机分为两组(异丙酚组、咪唑安定组),监测手术前、主动脉阻断10 min和复温至31℃时血气指标等的动态变化.结果与手术前比,主动脉阻断10 min和复温后,血液pH、PaCO2、HCO3-、BEB两组均有明显变化(P<0.05),但两组间差异无显著性(P>0.05).结论异丙酚和咪唑安定在体外循环麻醉中其对酸碱度无明显的影响. 相似文献
54.
55.
Geza Remak MD Omar D. Hottenstein PhD Dr. Eugene D. Jacobson MD 《Digestive diseases and sciences》1994,39(8):1655-1664
We evaluated the effects of potential factors in autoregulatory escape from norepinephrine-induced vasoconstriction in rat anterior mesenteric artery. We determined mesenteric artery blood flow velocity with a pulsed Doppler, sonic flowmeter, and systemic arterial blood pressure with a transducer. A 4-min norepinephrine infusion (0.125–1.0 × 10–8 M/min) intravenously evoked a dose-dependent, initial vasoconstriction that was followed by rapid escape of blood flow toward or above the control value during sustained norepinephrine administration. Neonatal capsaicin treatment enhanced vasoconstrictor responses to norepinephrine but failed to affect escape parameters. Propranolol decreased norepinephrine-induced escape dose dependently. Adenosine deaminase attenuated escape, and the combination of this enzyme plus propranolol nearly abolished escape from norepinephrine-induced vasoconstriction. Methylene blue also diminished autoregulatory escape. These findings suggest that norepinephrine-induced autoregulatory escape involves simultaneous -adrenoceptor, purinergic, and endothelial mediation. Norepinephrine-evoked mesenteric vasoconstriction appears to involve predominantly 2-adrenoceptors and is modulated by peptidergic sensory nerves and adenosine.NIH grant number supporting these studies: USPHS # DK37050. 相似文献
56.
PONGRATZ G.; GANSSER R.; BACHMANN K.; SINGER H.; WORTH H. 《European heart journal》1994,15(7):1002-1004
Coronary aneurysms resulting from a previous episode of Kawasaki'sdisease are considered an important cause of myocardial infarctionin children. A case of a 19-year-old man presenting with anacute myocardial infarction associated with coronary aneurysmsis described. These coronary lesions were previously evaluatedangiographically and echocardiographically at the age of 13years, 5 months after the acute episode of a Kawasaki's disease. 相似文献
57.
Z. Milutinović 《European archives of oto-rhino-laryngology》1995,252(8):491-494
There are numerous surgical procedures now available to manage bilateral abductor paralyses of the vocal folds. These procedures have various success rates but mostly do not offer reliable and predictable postoperative results, and usually require ,tracheotomy. The technique described in this report is based on a trial study to obtain a safe airway for an affected patient and avoid tracheotomy, if possible. Submucosal cordectomy was used with lateral fixation of one vocal fold and preservation of the arytenoid. The procedure was performed by using continuous intravenous anesthesia, which does not require intubation of the patient's airway. Seven patients were operated with this technique with excellent postoperative results. The glottal airway was largely improved in all patients, with only minor temporary complications. 相似文献
58.
从中医理论探索方药的作用机理 总被引:2,自引:0,他引:2
杨进 《南京中医药大学学报》1999,(5)
主要以所承担过的科研课题的研究思路及研究结果为依据,论述从传统中医理论探索方药作用机理的重要性。文中从养阴生津方药治疗热瘀证的作用、血分证中运用活血化瘀法的作用、辛开苦降法的作用及解表法的作用等方面论述从中医的特有理论出发,可以在探索方药作用机理时提供思路、开拓新的研究领域。同时,中医传统证治理论也要不断发展、提高,在运用传统证治理论研究方药作用机理时,不能完全被其所束缚,随着对证治理论认识的发展,对方药作用机理的认识也必然会出现一个飞跃。 相似文献
59.
Mair P Hoermann C Mair J Margreiter J Puschendorf B Balogh D 《Acta anaesthesiologica Scandinavica》1999,43(4):452-457
BACKGROUND: Proteolytic enzymes and oxygen free radicals released from activated leucocytes contribute significantly to the organ dysfunction associated with cardiopulmonary bypass. Leucocyte depletion during extracorporeal circulation should reduce the release of these toxic compounds and thereby improve postbypass myocardial and pulmonary function. Recently, a leucocyte-specific arterial line filter to achieve leucocyte depletion during clinical perfusion has become commercially available. The aim of this study, therefore, was to evaluate the influence of the leucocyte depleting arterial line filter on proteolytic enzyme release, oxygen free radical release and postbypass pulmonary and myocardial function in patients undergoing bypass surgery. METHODS: Forty patients undergoing elective aortocoronary bypass surgery were included into this prospective, randomized clinical study, 20 in the leucocyte depletion (LG-6 group, leucocyte-specific arterial line filter) and 20 in the control group (AV-6 group, standard arterial line filter). White cell count, differential white cell count, plasma elastase concentration, plasma malondialdehyde concentration and C-reactive protein were determined before, twice during and immediately after cardiopulmonary bypass, at the end of surgery and 6 and 20 h thereafter. RESULTS: White cell count, differential white cell count, malondialdehyde and C-reactive protein were not significantly different between LG-6 and control patients. Plasma elastase concentrations were significantly (P < or = 0.03) higher during and immediately after extracorporeal circulation in LG-6 group patients. Need for inotropic support, arterial pO2 after extracorporeal circulation and perioperative CK MB mass and troponin I release were not different between the two groups of patients. CONCLUSION: The use of a leucocyte depleting arterial line filter is associated with an increased release of the proteolytic enzyme elastase, but does not reliably and consistently achieve effective leucocyte depletion during clinical perfusion. In contrast to previous studies, we could not demonstrate any significant difference in postbypass pulmonary or myocardial function between patients perfused with the leucocyte-specific arterial line filter and control patients. Our data do not support the routine use of a leucocyte depleting arterial line filter during clinical perfusion in patients undergoing elective aortocoronary bypass surgery. 相似文献
60.
Holliday MA 《Pediatric nephrology (Berlin, Germany)》1999,13(9):989-995
This review highlights characteristics of extracellular fluid (ECF) that are often overlooked. ECF has, in addition to plasma
and interstitial fluid (ISF) surrounding cells, a third large compartment, the ISF of skin and connective tissue. This acts
as a reservoir that gives up ECF to plasma volume (PV) in order to sustain circulation in the event of either shock or dehydration.
While Starling forces drive filtration, ECF is returned to PV more by lymph and less by Starling forces than previously appreciated.
Lymph return to PV is dependent on physical activity and muscle contraction to overcome gravity. Regional change in metabolic
rate alters the need for oxygen and nutrients that is met by a regional increase in capillary blood flow. Blood flow is controlled
by vasoactive compounds released in response to a drop in PO2; these relax capillary smooth muscle to increase blood flow and delivery of oxygen and nutrients. Plasma proteins, including
albumin, are filtered into the interstitium through larger pores than those filtering ECF. The rate of protein filtration
is set by size and charge of these larger endothelial pores and by size and charge of proteins. Charge of these pores, hence
albumin permeability, is regulated by many of the same vasoactive compounds that control capillary flow. As a consequence,
in response to gravitational stress and other forms of shock that reduce effective circulation, albumin as well as ECF is
rapidly shifted from plasma and sequestered in ISF. When this has occurred, as in burn shock, restoration is better effected
by generous expansion of ECF with Ringer’s solution alone, rather than with Ringer’s solution supplemented with human serum
albumin or other colloid. Restoring both PV and ISF volume restores lymph circulation and returns sequestered albumin to PV.
Received: 12 November 1998 / Revised: 30 March 1999 / Accepted: 2 April 1999 相似文献