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991.
Clonidine stimulates locus coeruleus neurons by an α2-adrenoceptor-independent mechanism which probably involves imidazoline receptors. To study this effect, single-unit extracellular
recordings in the locus coeruleus were performed in anaesthetised rats after complete, irreversible inactivation of α2-adrenoceptors by the alkylating agent N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ) (6 mg/kg i.p.; 6 h before experiments).
After this pretreatment, clonidine applied into the locus coeruleus failed to produce any change in the cell firing rate.
However, clonidine applied intravenously (320–2560 μg/kg), or locally (0.5–2.0 μl of 0.02 M) into the nucleus paragigantocellularis,
a major locus coeruleus afferent, stimulated locus coeruleus neurons (increasing the firing rate by approximately 90%). Electrical
lesions of the nucleus paragigantocellularis greatly attenuated the clonidine induced stimulation of locus coeruleus neurons
ipsilateral to the lesion when applied intravenously. Blood pressure which was recorded simultaneously with cell recording,
remained unaffected after clonidine administration in EEDQ pretreated rats.
These results indicate that the clonidine-induced stimulation of locus coeruleus neurons is an indirect effect mediated by
imidazoline receptors located on paragigantocellularis neurons projecting to the locus coeruleus.
Received: 12 August 1996 / Accepted: 13 October 1996 相似文献
992.
目的观察伏隔核毁损手术对阿片相关性障碍病人的人格影响。方法选择我院手术治疗的男性病人26例,手术前后采用艾森克个性问卷(EPQ)施测,调查3个人格维度[内外向(E)、神经质(N)及精神质(P)]和1个效度量表(L)。结果术前E标准分平均为(55.96±12.89)分,N为(64.81±11.27)分,P为(62.50±8.51)分,L为(40.19±9,85)分;术前、术后粗分与常模比较,E、N、P、L差异有统计学意义。手术前后自身对照分析结果显示:仅N分差异有统计学意义:术后N标准分下降16例,平均下降12.25分。结论手术前病人呈不稳定、偏外向人格。手术矫治了部分病人的病理性心理症状,使EPQ的N分下降,病人不稳定型人格特质改善。手术未使病人外倾、精神质高分、掩饰性偏低等人格特征改变。 相似文献
993.
[目的] 探讨糖尿病周围神经病变(diabetic peripheral neuropathy,DPN)患者血小板活化与中医证型分布的关系。[方法] 收集2020年2月至2022年12月于本院住院确诊的DPN患者188例。中医证型采用指标聚类分析,绘制聚类图。采用简单对应分析中医证型与病变程度的对应性,比较不同中医证型的一般临床资料、血小板参数及血小板活化物,从而探讨血小板活化与中医证型分布的关系。[结果] 截取聚类图的不同位置,证型分型不同,其中D点截取分为5个证型:阳虚证、气虚证、阴虚证、瘀血痹阻证及痰湿阻络证。188例DPN患者中,痰湿阻络证18例(9.57%)、瘀血痹阻证53例(28.19%)、阳虚证28例(14.89%)、阴虚证39例(20.74%)、气虚证50例(26.60%)。DPN病变程度分级为Ⅰ级56例(29.79%)、Ⅱ级76例(40.43%)、Ⅲ级56例(29.79%)。痰湿阻络证和瘀血痹阻证在二维投影图中间,并未偏向DPN病变程度某一分级;阳虚证偏向Ⅲ级,阴虚证偏向Ⅱ级,气虚证偏向Ⅰ级。与气虚证比较,阴虚证、阳虚证患者的血小板(blood platelet ,PLT)计数、平均血小板体积(mean platelet volume,MPV)、血小板分布宽度(platelet distribution width,PDW)、E26转录因子-1(E26 transformation specific-1,ETS-1)、血小板活化因子(platelet activating factor,PAF)及血小板颗粒膜蛋白-140(granular membrane protein-140,GMP-140)均明显升高(P<0.05);与阴虚证比较,阳虚证患者的PLT、MPV、PDW、GMP-140、PAF、ETS-1均明显升高(P<0.05)。[结论] 临床可常规将DPN分为阳虚、气虚、瘀血痹阻、阴虚和痰湿阻络5个证型。随着DPN进展,中医证型也发生从气虚到阴虚到阳虚的转化,而瘀血痹阻和痰湿阻络伴随DPN患者各阶段。在DPN进展中,血小板活化可能参与中医证型转化过程。 相似文献
994.
A lytic lesion with soft-tissue extension in the sacrum of a 47-year-old man was needle-biopsied under computed tomographic
(CT) guidance using an 18-gauge cutting needle. The cytologic appearance of the lesion and immunohistochemical staining were
diagnostic of Ewing’s sarcoma. Specifically, a new marker (O13) for the presence of glycoprotein p30/32 mic2 in Ewing’s sarcoma
was utilized. 相似文献
995.
Kimiko Tamagawa Ryoko Ishibashi Yoshihiko Mizuno Kazuhiko Komiya Masaya Oda Masako Shinozaki Kiyoko Kurata Junichi Satoh Yoshio Morimatsu 《Neuropathology》1993,13(4):269-275
Three cases with cavitary lesions on the cerebral convexities in twin gestation complicated by a single intrauterine fetal demise were investigated clinicopathologically. They all exhibited profound mental retardation and severe motor disturbance due to rigidospastic tetraplegia. The co-twins were macerated. Neuropathologically, malformed lesions and destructive lesions coexisted in varying degrees according to the time in fetal life, at which insults probably occurred. The cavitary lesions were located bilaterally and symmetrically on the central, parietal and occipital region of the cerebral hemispheres, in some cases, including the frontal region. Case 1 showed an incomplete gyral pattern and porencephaly with polymicrogyria bordering the defect, thus allowing us to date the insult before the 5th fetal month. In case 2, multicystic encephalomalacia was disclosed with cortical dysgenesis exhibiting status marmoratus of the cortex. Case 3 displayed sclerotic cavitary lesions with sclerosis of the insula and a few instances of cortical dysgenesis. Based on the clinical data and pathological findings, the cavitary lesions of case3 may be dated in the third trimester of gestation. Case 2 can be considered to have sustained injuries between the times estimated for cases 1 and 3. As the pathogenesis of the congenital cavitary lesions, several concepts have been proposed: intrauterine DIC (Moore et al. 1969;Romero et al. 1984), vascular disruption (Hoyme et al. 1981;Jung et al. 1984), intrauterine infection such as cytomegalic inclusion disease (Friede et al. 1976), and hypoxia due to CO intoxication of the mother (Bank1 et al. 1967) or other cause. Though the pathological observation of our cases revealed no evidence of intrauterine DIC, renal cortic necrosis, intrauterine infection or occlusion of the intracranial vessels, long-term exposure to the dead twin might have contributed to the lesions of the liveborn co-twin. 相似文献
996.
997.
多层螺旋CT增强检查对乳腺病变的诊断价值 总被引:1,自引:0,他引:1
目的:探讨多层螺旋CT(MSCT)增强检查对乳腺疾病的鉴别诊断价值。方法:经手术病理证实的84位患者,共检出93例乳腺病变,其中浸润性导管癌57例,粘液癌4例,纤维腺瘤13例,导管内乳头状瘤4例,其他良性病变15例。CT检查先平扫,而后分别于静脉注射对比剂后28s、90s时进行二期增强扫描。对照手术病理结果,分析所有乳腺病变的CT表现。结果:乳腺良、恶性病变的平扫密度之间的差异无统计意义(P>0.05)。乳腺良、恶性病变的形状、边缘及强化形式之间的差异有统计意义(P=1.57×10-4;P=1.75×10-28;P=1.78×10-2)。以25HU为分界点,本组乳腺良、恶性病变动脉期强化程度之间的差别有高度统计意义(P<0.001)。MSCT诊断本组乳腺病变的敏感性为96.7%,特异性为90.6%,阳性预测值为95.2%,阴性预测值为93.5%。MSCT对61例乳腺癌腋窝淋巴结转移的术前检出率为88.8%。结论:多层螺旋CT增强检查在鉴别乳腺良恶性病变方面具有较高的诊断价值。 相似文献
998.
Many basic scientific and clinical studies support the utility of small fragment allografting in addressing an extensive spectrum of osteoarticular pathology, with its use in the tibiotalar joint still an evolving application. The operative procedure in the ankle is technically straightforward but demands precision to achieve reproducible results and to minimize early graft failures related to surgical technique. Fresh osteochondral allografting of the tibiotalar joint is best understood as a management strategy in the patient that presents with a symptomatic OLT, or advanced ankle arthropathy at an age or activity level not optimally suited for total joint replacement or arthrodesis. The treatment goal of joint-sparing biologic reconstruction is to relieve pain and maintain function to delay the need for ankle fusion or total replacement indefinitely, while at the same time not restricting future treatment options. The emergence of fresh osteochondral allografting for the ankle has demonstrated encouraging results, but its remaining shortcomings are also testament to the lack of viable treatment options in this challenging patient population. 相似文献
999.
D. Ryglewicz M. Baranska-Gieruszczak K. Niedzielska T. Kryst-Widzgowska 《Acta neurologica Scandinavica》1990,81(6):488-490
The present study was undertaken to assess the diagnostic value of CT in patients with poststroke epilepsy, related to EEG in revealing the factors contributing to the development of epileptic fits. The EEG and CT results were evaluated in 50 patients with poststroke epilepsy and compared with those of 50 patients without epilepsy after stroke. Cortical and extensive lesions involving the cortex were more frequent among patients with poststroke epilepsy. Sparing of certain parts of cerebral cortex was observed within vasogenic lesion. This type of change was only found in the poststroke epilepsy group and may be responsible for development of epileptic fits. It seems that CT has a higher diagnostic value than EEG in evaluating the risk of development of poststroke epilepsy. 相似文献
1000.
We have examined the effect of axotomy on the conduction velocity of unmyelinated sensory fibres in the vagus nerve of the rabbit. In an in vitro preparation of the nodose ganglion, conduction velocity was calculated for each cell from the latency of the intracellularly recorded action potential evoked by vagus nerve stimulation. The average velocity of sensory fibres conducting at less than 1.1 m/s, was 0.53 m/s in 287 control cells and 0.45 m/s in 269 neurones recorded 10 days after cutting the vagus nerve. Therefore, peripheral axotomy decreases conduction velocity in mammalian unmyelinated sensory axons. 相似文献