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11.
Background: Reports of major and minor sequelae following lidocaine spinal anesthesia have generated interest in an alternative short-acting intrathecal agent. Of the available anesthetics suitable for short-duration spinal anesthesia, prilocaine is perhaps the most promising agent. However, data comparing the neurotoxicity of these agents are lacking. Accordingly, the present experiments investigate whether prilocaine and lidocaine differ with respect to sensory impairment and histologic damage when administered intrathecally in the rat.

Methods: Ninety rats were divided into three groups to receive an intrathecal infusion of 2.5% prilocaine in saline, 2.5% lidocaine in saline, or normal saline. The animals were assessed for persistent sensory impairment 4 days after anesthetic administration using the tail-flick test. Three days later, the animals were killed, and specimens of the spinal cord and nerve roots were obtained for histopathologic examination.

Results: Prilocaine and lidocaine produced equivalent elevations in tail-flick latency that differed significantly from saline. Histologic injury scores with prilocaine were greater than with lidocaine, but this difference did not reach statistical significance.  相似文献   

12.
广西医学院儿少卫生教研室受区卫生厅委托于1985年9月开始举办为期半年的学校卫生医师培训班。来自基层防疫站和学校的31名学  相似文献   
13.
14.
张亦农 《上海医药》2005,26(8):353-353
Biocon公司是印度重要的生物技术公司之一,最近,该公司与Karolinska学院(瑞典最主要的医科大学)签署了一份协议,根据这项协议,双方将在研究、教育领域开展合作。此协议内容包括合作开发产品和共同研究规划。印度生物技术企业欲与瑞典开展合作@张亦农  相似文献   
15.
Background: Despite decades of use, controversy remains regarding the extent and time course of cephalad spread of opioids in cerebrospinal fluid (CSF) after intrathecal injection. The purpose of this study was to examine differences between two often used opioids, morphine and fentanyl, in distribution in the CSF after intrathecal injection.

Methods: Eight healthy volunteers received intrathecal injection of morphine (50 [mu]g) plus fentanyl (50 [mu]g) at a lower lumbar interspace. CSF was sampled through a needle in an upper lumbar interspace for 60-120 min. At the end of this time, a sample was taken from the lower lumbar needle, and both needles were withdrawn. CSF volume was determined by magnetic resonance imaging. Pharmacokinetic modeling was performed with NONMEM.

Results: Morphine and fentanyl peaked in CSF at the cephalad needle at similar times (41 +/- 13 min for fentanyl, 57 +/- 12 min for morphine). The ratio of morphine to fentanyl in CSF at the cephalad needle increased with time, surpassing 2:1 by 36 min and 4:1 by 103 min. CSF concentrations did not correlate with weight, height, or lumbosacral CSF volume. The concentrations of morphine and fentanyl at both sampling sites were well described by a simple pharmacokinetic model. The individual model parameters did not correlate with the distance between the needles, CSF volume, patient height, or patient weight.  相似文献   

16.
Background: The study hypothesizes that nitrous oxide (N2O) releases opioid peptide in the brain stem, which results in inhibition of [gamma]-aminobutyric acid-mediated (GABAergic) neurons that tonically inhibit the descending noradrenergic inhibitory neurons (DNIN), resulting in activation of DNIN. In the spinal cord, activation of DNIN leads to the release of norepinephrine, which inhibits nociceptive processing through direct activation of [alpha]2 adrenoceptor and indirect activation of GABAergic neurons through [alpha]1 adrenoceptor. Arising from this hypothesis, it follows that GABAergic neurons will modulate the antinociceptive effect of N2O in diametrically opposite directions at supraspinal and spinal levels. The authors have tested this tenet and further examined the effect of midazolam, a GABA-mimetic agent, on N2O-induced antinociceptive effect.

Methods: Adult male Fischer rats were administered muscimol (GABAA receptor agonist) intracerebroventricularly (icv), gabazine (GABAA receptor antagonist) intrathecally (intrathecal), or midazolam intraperitoneally (intraperitoneal). Fifteen minutes later, they were exposed to air or 75% N2O and were subjected to the plantar test after 30 min of gas exposure. In some animals administered with midazolam, gas exposure was continued for 90 min, and the brain and spinal cord were examined immunohistochemically.

Results: The N2O-induced antinociceptive effect, which was attenuated by icv muscimol, intrathecal gabazine, and intraperitoneal midazolam. Midazolam inhibited N2O-induced c-Fos expression (a marker of neuronal activation) in the pontine A7 and spinal cord.  相似文献   

17.
辛静 《上海医药》2005,26(8):375-375
印度生物技术主导企业协会(Biotechnology-LedEnterprisesofIndia)计划在美国设立分会,目的是为了在美国发展生物技术工业。美国当地商界有影响的权威人士Sartorious将担任该分会的名誉会长。印度生物技术界试图开拓美国市场@辛静  相似文献   
18.
颈部烧伤后疤痕挛缩、颌颈粘连的治疗方法较多,各有利弊。自1990年12月以来,我们使用双叶瓣治疗颈部疤痕粘连,获得较好效果,现报导如下。皮瓣设计和手术方法一、皮瓣设计,以肩颈部为基部,设计一双叶瓣(即a瓣,b瓣)。a瓣通常与疤痕紧邻,在锁骨中1/3或其附近。a瓣的大小  相似文献   
19.
With the method of rapid gel sequencing, the complete nueleotide sequence of Fasciolopsis buski 5S rRNA has been determined: AAC GGG AUG AAG CUA GAC AUG UGG CGG CCU AGU UGG AGG UCG GAA CUC GGA AGU UAA GGA AUG UUG GGC CUG GUU AGU ACU GGU AUG GGU GAC CUU GGG AAU ACC GGG UGU UGC GUC CA_(OH) This have been compared with 553 species of other organisms 5S rRNA sequences previously published and fitted to a secondary structural model.  相似文献   
20.
白洋淀污染一直是国家和河北省所关注的问题,对白洋淀上游蓄污工程沿岸小环境调查表明;饮用深层地下水受到城市工业废水的污染,主要污染物为有机物。污染区儿童贫血率、白细胞计数、舒张压高于非污染区,白细胞吞噬率低于非污染区,居民恶性肿瘤标化死亡比高于非污染区,肝癌标化死亡比明显上升。  相似文献   
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