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11.
The mechanism of action of systemitically administered(±)-MDMA (3, 4-methylenedioxymethamphetamine) on spontaneously active neurons in the medial prefrontal cortex (mPFc) of chloral hydrate anesthetized rats was examined using standard single unit extracellular recording techniques. Intravenously administered MDMA dose-dependently decreased the firing rates of the majority of mPFc neurons in control rats. In contrast, in rats that were pretreated withp-chlorophenylalanine (PCPA), which depletes the brain serotonin (5-hydroxytryptamine, 5-HT) content by inhibiting tryptophan hydroxylase, the rate-limiting enzyme in the synthesis of 5-HT, MDMA was largely ineffective in inhibiting the firing of mPFc cells. In PCPA-treated animals, the administration of 5-hydroxytryptophan (5-HTP), which presumably restored the brain 5-HT content, but notl-DOPA, reinstated MDMA's inhibitory action in PCPA-treated rats. In rats that were pretreated withα-methyl-p-tyrosine (AMPT), which depletes the brain dopamine (DA) content by inhibiting tyrosine hydroxylase, the rate-limiting enzyme in the synthesis of DA, MDMA inhibited the firing of all of the mPFc cells. MDMA's effect on mPFc neurons was reversed by 5-HT receptor antagonists such as granisetron and metergoline. These results strongly suggest that MDMA exerts its action on mPFc cells indirectly by releasing endogenous 5-HT. 相似文献
12.
Eiji Takeuchi Yuji Nimura Shin-ichi Mizuno Hideaki Suzuki Shinsuke Iyomasa Masaki Terasaki Hiroshi Kuriki Keiko Tamiya-Koizumi Shonen Yoshida 《Journal of Hepato-Biliary-Pancreatic Surgery》1997,4(3):254-262
Hepatocyte regeneration has been widely investigated, with the mitotic index and the incorporation of [3H]thymidine being used as regeneration markers. We focused on the induction of DNA replication enzymes, particularly DNA polymerases
(pol) α, δ, and ε. Using rat models, we have shown that the activity of pol α in crude liver extract well represents the regenerating
capacity of hepatocytes. Using pol α as an indicator, we analyzed liver regeneration in rat models under various conditions:
obstructive jaundice, external or internal biliary drainage, and the obstruction of portal vein branches. It has been revealed
that the ligation of the common bile duct alone induces a certain amount of hepatocyte proliferation. It was striking that
external biliary drainage suppressed regeneration capacity in cholestatic rat liver after partial hepatectomy. The strong
regeneration in nonligated lobes induced by portal branch ligation was similar to the liver regeneration seen after partial
hepatectomy with respect to the induction of DNA polymerases. Taken together, the aspects of DNA replication, particularly
the induction of DNA polymerases, may contribute to shedding new light on the regeneration of human liver.
This work was supported in part by a Grant-in-Aid for General Scientific Research and for Cancer Research from the Ministry
of Education, Science and Culture, Japan, and by grants from the Uehara Memorial Foundation 相似文献
13.
带血管蒂舟骨瓣移位术的应用解剖 总被引:3,自引:0,他引:3
目的:为治疗距骨骨折提供新术式的解剖学基础.方法:在30侧灌注红色乳胶的成人下肢标本上,对舟骨背侧面形态、血供来源进行观测.结果:舟骨背侧面动脉主要来自内踝前动脉、跗内侧动脉以及足底内侧动脉浅支,分别发3~5支、1~3支和1~2支外径在0.2~1.0mm之间的骨膜支,形成骨膜动脉网.结论:以内踝前血管为蒂,可切取舟骨背侧2.0cm×1.0cm×0.5cm大小的骨瓣,用于距骨颈骨折修复.术式经临床应用证实,手术简便,效果可靠. 相似文献
14.
视网膜分支静脉阻塞和新生血管形成 总被引:10,自引:1,他引:9
分析视网膜分支静脉阻塞240例245只眼(5人为双眼),其中主干分支阻塞208只眼,黄斑分支阻塞37只眼。79只眼产生了新生血管,占总数的32.2%,占主干分支阻塞的37.9%.玻璃体出血39只眼,占分支阻塞的15.9%,占新生血管的49.4%。新生血管的危险因素是无灌注区形成、动脉灌注不良、阻塞处静脉严重受压.新生血管的发生随病程时间延长而增高,病程5年以上者高达83.3%。分支静脉阻塞盲目者20只眼占8.2%,其中因新生血管及并发症致盲者14只眼,占盲目的70%,占分支静脉阻塞的5.7%.
(中华眼底病杂志,1994,10:67-70) 相似文献
15.
The rearrangement of terminations from the bed nucleus of stria terminalis (BST) was examined in the medial amygdaloid nucleus (MAN) at 2 months following the lesion of the accessory olfactory bulb (AOB) using an electron microscopy and degeneration study. At 2 days following a BST lesion, the number of degenerating synapses was 0.7 ± 0.1 (mean±S.E.M.) per unit area (2500 μm2 in the molecular layer, and 3/0 ± 0.3 in the cellular part. At 2 months after an AOB lesion, the degenerating synapses from the AOB had completely disappeared from the MAN. The BST was then lesioned at 2 months after the AOB lesion and, 2 days following this BST lesion, the degenerating synapses were counted in MAN. The numbers observed were 3.3 ± 0.6 per unit area in the molecular layer and 4.5 ± 0.4 in the cellular part. Therefore, the number of these degenerating synapses increased significantly within the molecular layer, though, in the cellular part the number of synapses was not significantly elevated over control. No differences in postsynaptic profiles (ratio of synapses on dendritic spine to dendritic shaft) were observed after the AOB lesion. These results indicate that the BST fibers formed new synapses in the molecular layer following the denervation of AOB fibers. The possibility of new synapse formation by other afferent fibers in addition to the AOB fibers is discussed as is the relationship between lesion induced synaptic reorganization and functional recovery after injury. 相似文献
16.
目的探讨一种以腓肠神经内侧头肌支切断来改善小腿外形的新方法。方法在腘窝处切开,暴露腓肠神经内侧头肌支,并切断,使局部肌肉失神经萎缩,而缩小小腿的容积。结果本组4例,术后小腿周径平均缩小3.6±0.8cm,小腿外形满意。结论本方法为一简单、安全而有效的技术,能达到缩小小腿部的目的。 相似文献
17.
内眦赘皮与重睑成形同期手术的一种新方法 总被引:12,自引:1,他引:11
目的 探索适合同时行重睑成形术和内眦赘皮矫正术的新方法。方法 根据内眦赘皮深部眼轮匝肌结构上的异常特点,遵循内眦赘皮的上睑(倒向性内眦赘皮除外)内侧睑缘处皮肤短缺和尽量减少局部皮肤瘢痕的原则,设计适合同时行重睑成形术的新内眦赘皮矫正术(反Stallard法)。结果 临床应用86例,进行了为期6个月以上的随访,结果所有患者的重睑为稳定性平行型重睑,内眦已完全或大部分开大,手术效果满意。结论 此内眦赘皮矫正术能够充分矫正内眦部结构上的异常,而且适合与重睑成形术同期施行,是一种效果稳定,结果满意的术式。 相似文献
18.
Overview Excess spasticity leads to disability that is marked by impaired locomotion, handicapping deformities and, if not controlled,
discomfort and pain. Selective peripheral neurotomy in the child is indicated for severe focal spasticity, when botulinum
toxin injections cannot delay surgery any longer.
Materials and methods Preoperative motor blocks mimicking the outcome of the surgical procedure are essential to establish the objectives of neurotomy.
In the lower limb, obturator neurotomy is indicated for spasticity in the adductor muscles, hamstring neurotomy for the knee flexion and tibial
neurotomy for the spastic foot. Anterior tibial neurotomy is indicated for the extensor hallucis spasticity and femoral neurotomy
for spasticity in the quadriceps. In the upper limb, neurotomy of the pectoralis major and teres major nerves is indicated for spasticity of the internal rotators of the shoulder.
Neurotomy of the musculocutaneous nerve is indicated for spasticity of the flexors of the elbow, and neurotomy of median and
ulnar nerves are indicated for spasticity of the pronators and flexors of the wrist and fingers.
Conclusion Selective peripheral neurotomy is a valuable neurosurgical procedure in well-trained surgical hands for severe focalised spasticity. 相似文献
19.
目的 采用手术方法结扎门静脉分支,观察对侧肝脏的再生状态。方法 健康Wistar雄性大鼠60只,随机均分成结扎组和假结扎组,在乙醚麻醉下行门静脉左支结扎和假结扎手术,分别在术后第1、2、3、7及14d用乙醚麻醉动物,心脏采血检测血清ALT值,取出肝脏后称重量;在光镜下观察肝组织的病理变化,并计数肝细胞核分裂指数;采用免疫组化的方法计数增殖细胞核抗原(PCNA)指数;在电镜下观察肝细胞超微结构变化。结果 ①血清ALT值结扎组与假结扎组比较在术后第1d升高(P〈0.01),但在第2d开始恢复正常;②肝脏重量两组间差异无统计学意义(P〉0.05);③肝细胞核分裂指数结扎组与假结扎组比较,术后第1~3d明显升高,第2d达高峰,第3d有所下降,但仍高于假结扎组(P〈0.01),以后逐渐恢复正常;④PCNA阳性细胞计数结扎组与假结扎组比较,术后第1~3d明显增多,第2d达高峰,第3d有所减少,但仍高于假结扎组(P〈0.01),以后逐渐恢复正常。结论 ①大鼠门静脉左支结扎后,引起未结扎侧肝细胞的活跃再生,再生后的肝脏可恢复原来的重量;②大鼠75%肝叶的门静脉分支结扎不影响肝功能,是安全可行的;③大鼠门静脉分支结扎可以作为研究肝脏再生动物模型的方法。 相似文献
20.