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1.
Objective To investigate the effect of dexamethasone on the toxicity of bupivacaine in murine neurons.Methods Murine neuroblastoma cell line N2a was obtained from ATCC cell bank (USA). The cells were cultured in 10% fetal cow serum/MEM culture medium and divided into 4 groups voup I control (Con); group II bupivacaine ( Bup); group Ⅲ dexamethasone (Dex) and group IV Dex + Bup. The culture medium contained bupivacaine 900 μmol/L in group Bup and dexamethasone 1 μmol/L in group Dex respectively. In group Dex + Bup ( IV ) Bup was added to the culture medium with a final concentration of 900 μmol/L at 12 h after pretreatment with Dex 1 μmol/L. The cells were inoculated in 24 well plates (0.5 ml in each well, 24 wells in each group) and 10 cm culture dishes (7 ml in each dish, 4 dishes in each group). The release rate of LDH was calculated and the morphology of the cells and nucleus condensation (by Hoechst 3334224 fluorescent staining) was detected at 9 h of incubation in 24 well plates. The mitochondrial transmembrane potential (by JC-1 assay) and phosphorylation of Akt and ERKs (by Western blot) were measured at 5 h of incubation in 24 well plates and in culture dishes respectively. ResultsBupivacaine caused severe damage to the N2a cells as evidenced by increase in LDH release and nucleus condensation (apoptosis), dephosphorylation of Akt and ERKs, decrease in mitochondrial transmembrane potential and severe morphological changes. Dexamethasone pretreatment significantly attenuated bupivacaine-induced neurotoxicity. Conclusion Dexamethasone can protect N2a cells from bupivacaine-induced neurotoxicity through stabilization of mitochondrial transmembrane potential and inhibition of dephosphorylation of Akt and ERKs. 相似文献
2.
护理工作中院内感染相关问题与对策 总被引:5,自引:2,他引:3
目的 :提出护理工作与院内感染相关问题与对策。方法 :通过监测 ,找出护理工作引起院内感染存在的问题及薄弱环节 ,并制定相应对策。结果 :建立严格的控制感染的管理制度 ,层层落实把关 ,主动和独立地判断出行之有效的预防措施。结论 :在感染管理工作中严格认真执行消毒、灭菌、无菌操作 ,最大限度地避免因护理工作失误而引起的医院内感染 相似文献
3.
法半夏罗汉果川贝枇杷膏与强力枇杷露药理作用的比较研究 总被引:3,自引:0,他引:3
法半夏罗汉果川贝枇把膏与强力批他露均有镇咳祛痰作用,罗汉果川贝枇把膏尚能平喘抗炎。 相似文献
4.
阿奇霉素治疗呼吸道感染的药理特性与临床分析 总被引:1,自引:1,他引:0
阿奇霉素是近年来开发的大环内酯类抗生素,本品是通过阻碍细菌转肽过程,抑制蛋白质合成达到抑菌作用。我院呼吸内科自2006年2月~8月收治35例肺部疾患患者,将阿奇霉素用于呼吸道感染取得满意疗效。本文将概述阿奇霉素的药理特性及报道治疗呼吸道感染的临床资料。 相似文献
5.
香茶菜属植物的化学成分与药理作用研究进展 总被引:2,自引:0,他引:2
我们主要综述了国内近年来有关香茶菜属植物在化学成分、药理作用、临床应用方面的研究进 展,并且讨论了这一领域的研究方向。 相似文献
6.
The synthesis of O-methylgortschakoine and O-methylpetaline was achieved through an unambiguous route. Pharmacological testing of O-methylgortschakoine in comparison to papaverine and 7,8-dimethoxy-N-methyltetrahydroisoquinoline, indicated that it possesses hypotensive, neuromuscular blocking and smooth muscle relaxant activities. 7,8-Dimethoxy-N-methyltetrahydroisoquinoline showed only nonspecific smooth muscle relaxation in our testing system. The 1-(p-methoxybenzyl)-substituent of O-methylgortschakoine appears to be required for this hypotensive and neuromuscular blocking effect. The quaternary analogue O-melthylpetaline was found to possess a more potent neuromuscular blocking activity. 相似文献
7.
LI-JEN LIN JIUNN-LEE LIN LING-PING LAI JYH-HONG CHEN YUNG-ZU TSENG WEN-PIN LIEN 《Pacing and clinical electrophysiology : PACE》1998,21(7):1375-1379
The purpose of this study was to investigate the atrioventricular AV nodal physiology and the inducibility of AV nodal reentrant tachycardia (AVNRT) under pharmacological autonomic blockade (AB). Seventeen consecutive patients (6 men and 11 women, mean age 39 ± 17 years) with clinical recurrent slow-fast AVNRT received electrophysiological study before and after pharmacological AB with atropine (0.04 mg/kg) and propranolol (0.2 mg/kg). In baseline, all 17 patients could be induced with AVNRT, 5 were isoproterenol-dependent. After pharmacological AB, 12 (71 %) of 17 patients still demonstrated AV nodal duality. AVNRT became noninducible in 7 of 12 nonisoproterenol dependent patients and remained noninducible in all 5 isoproterenol dependent patients. The sinus cycle length (801 ± 105 ms vs 630 ± 80 ms, P < 0.005) and AV blocking cycle length (365 ± 64 ms vs 338 ± 61 ms, P < 0.005) became shorter after AB. The antegrade effective refractory period and functional refractory period of the fast pathway (369 ± 67 ms vs 305 ± 73 ms, P < 0.005; 408 ± 56 ms vs 350 ± 62 ms, P < 0.005) and the slow pathway (271 ± 30 ms vs 258 ± 27 ms, P < 0.01; 344 ± 60 ms vs 295 ± 50 ms, P < 0.005) likewise became significantly shortened. However, the ventriculoatrial blocking cycle length (349 ± 94 ms vs 326 ± 89 ms, NS) and effective refractory period of retrograde fast pathway (228 ± 38 ms vs 240 ± 80 ms, NS) remained unchanged after autonomic blockade. Pharmacological AB unveiling the intrinsic AV nodal physiology could result in the masking of AV nodal duality and the decreased inducibility of clinical AVNRT. 相似文献
8.
采用薄层色谱法对克痛喷剂中蟾酥、冰片、大黄、栀子、白芷进行定性鉴别;并应用气相色谱法对冰片的含量进行测定。实验结果证明方法简便,斑点圆整,重现性及专属性均好,可国该制剂的质量控制标准。 相似文献
9.
G. Adaikan G. N. Beatch T. L. Lee S. S. Ratnam M. J. A. Walker 《Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy》1992,6(Z1):345-352
Tedisamil is a new bradycardic agent, previously shown to block transient outward and delayed rectifier potassium currents in cardiac tissue [1,2]. In the present study tedisamil caused bradycardia and Q-Tc widening in rats and primates. Q-Tc widening is indicative of class III antiarrhythmic actions. In keeping with this, tedisamil had antiarrhythmic activity against electrical and ischemia-induced arrhythmias in rats. In rats, 0.5–4 mg/kg IV tedisamil caused parallel and dose-related increases in action-potential duration, Q-Tc interval, and refractory period; and decreases in maximum ventricular following frequency. In primates after 0.5–2.0 mg/kg IV, findings were similar for indices of Q-T widening and decreases in maximum ventricular following frequency. Tedisamil did not change QRS width, nor did it increase threshold currents for capture of ventricles, nor for fibrillo-flutter at doses below 4 mg/kg in rats. These findings were consistent with the lack of significant sodium-channel blockade. However, upon increasing the dose to 4 mg/kg, ventricular fibrillo-flutter could not be induced in rats by electrical stimulation; instead, only ventricular tachycardias with slow rates occurred. Ischemia-induced ventricular fibrillation was reduced in a dose-related manner by tedisamil in rats. The overall incidence of ischemia-induced ventricular tachycardia was not markedly reduced, but rates during tachycardic episodes were lower. When pacing was used to overcome tedisamil-induced bradycardia, antiarrhythmic actions during ischemia were more pronounced. These findings are consistent with the hypothesis that tedisamil increased refractoriness, which resulted in extended path lengths for reentry circuits and slower rates during episodes of ventricular tachycardia. High doses of tedisamil increased path lengths so much that the multiple reentry circuits of fibrillation could no longer occur. The limited study in primates suggests similar mechanisms could occur in humans. 相似文献
10.
Caserotti P Aagaard P Simonsen EB Puggaard L 《European journal of applied physiology》2001,84(3):206-212
Elderly people (age 75 years; n=48 males and 34 females) were studied in order to elucidate gender differences in elderly subjects on the determinants of
muscle power (force and velocity) during a stretch-shortening cycle. All subjects performed three maximal counter-movement
vertical jumps using both legs, on a force platform (Kistler 9281 B). The eccentric (Ep) and concentric (Cp) phases of the
jumps were analyzed. The Ep was further divided into an acceleration phase (Epacc: from the start of the downward movement to the maximal negative velocity) and deceleration phase (Epdec: from the maximal negative velocity to the end of the downward movement). Jump height for the men was higher than for the
women (P < 0.001). During both Epacc and Epdec no significant differences were observed between males and females in force and power generation. However, the men had a
higher peak muscle power during the Cp, which may be explained exclusively by the velocity determinant (P < 0.001). No specific gender-related strategy appeared to influence the motor pattern of the movement. The comparable eccentric
force generation of the leg extensors in both genders suggests a similar ability to cope with eccentric muscle actions during
everyday activities. In contrast, the marked lower capacity for concentric contractions in women may result in an impaired
performance, especially in activities where intense and rapid movements are essential, for example when reversing a forward
fall. This may be one reason why elderly women are more prone to falls than are elderly men.
Accepted: 19 September 2000 相似文献