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1.
These studies provide information on the changes in the ultrastructure in the caudate nucleus of aged cats. The major findings was that there was a decrease in the density of synapses in caudate neuropil. This decrease occurred in animals after 3 years of age and remained relatively constant in older animals. In conjunction with this change a population of unusually long synapses also occurred. These larger synaptic appositions were associated with enlarged spine heads. The caudate also showed a number of qualitative ultrastructural alterations. Many neurons contained accumulations of lipofuscin or lipopigment granules in aged animals. These inclusions occurred in both soma and dendrites of neurons and all types of glial cells. A unique configuration of collapsed agranular cisterns also was observed in aged animals. The present results indicate that decreases in synaptic density may by one morphological event underlying functional alterations observed in caudate neurons in aged cats.  相似文献   
2.
Summary Isolated angiitis of the central nervous system (IAC) was diagnosed in a 40-year-old Caucasian male by histological examination of a leptomeningeal biopsy specimen, and the exclusion of systemic inflammatory or infective disease. Therapy with prednisone 30 mg/day and cyclophosphamide 100 mg/day resulted in clinical and radiological improvement, which have been maintained for an 8-month follow-up period. Magnetic resonance imaging (MRI) showed lesions implicating involvement of specific penetrating vessels at the base of the brain, an unusual complication of IAC, and allowed an accurate MRI-clinical correlation.  相似文献   
3.
肝尾叶切除     
肝尾叶深藏于肝门结构与下腔静脉之间,具有独立的管道系统,手术切除风险较大,作者结合2例肝尾叶切除的体会,复习文献,对肝尾叶的解剖、影像学特征、切除指征及手术方法进行了讨论。  相似文献   
4.
The effects of intraventricular nerve growth factor (NGF) or saline treatments on extracellular acetylcholine (ACh), dopamine (DA) and adenosine (Ade) levels in the cortex and striatum of rats with unilateral devascularizing cortical lesions were studied in vivo with microdialysis. The devascularizing cortical lesion produced a decrease in extracellular ACh levels in both cortex and striatum as compared to those in normal rats, while the NGF treatment produced a significant increase in ACh levels in both regions. NGF could even increase cortical ACh levels in normal rats. The cortical lesion produced a decrease in extracellular DA in the cortex, while the NGF treatment appeared to reverse this effect. No significant changes in DA were observed in the striatum. The present study gives evidence that a unilateral cortical devascularizing lesion leads to changes in extracellular ACh and DA levels in cortex and striatum and that these changes could be reversed with intraventricular NGF treatment.  相似文献   
5.
Summary Infarction in the territory of the anterior choroidal artery (AchA) has been the subject of several recent reports. To the classical clinical syndrome of hemimotor, hemisensory, and visual field deficit has been added hemiataxia acute pseudobulbar mutism, pure motor and pure sensory syndromes and disorders of higher cortical function. The definition of anatomic and clinical correlates to AchA stroke is aided by CT-MRI findings and reveals an unexpected superior extension of infarct to include the periventricular caudate nucleus and inferior corona radiata. Prognosis depends upon unilaterality, bilateral strokes having often a fatal outcome. Etiology and treatment may be intimately related to hypertension.  相似文献   
6.
肝尾状叶由于解剖位置特殊,位置深,难以显露,手术难度大,是肝脏外科领域手术操作的难点与研究热点.随着肝血流控制技术的发展、肝实质离断技术的提高,肝尾状叶肿瘤切除率明显提高[1].2006年4月至2008年10月,我科完成单独肝尾状叶血管瘤切除术9例,现将手术技巧与疗效报道如下.  相似文献   
7.
Dose-response curves for the elevation of homovanillic acid (HVA) levels, determined by high performance liquid chromatography using electrochemical detection, in the pre-frontal cortex and caudate of rats after acute treatment with 12 antipsychotic drugs are presented. The order of potency in both brain regions was: haloperidol fluphenazine > loxapine > trifluoperazine > thiothixene > molindone > clopenthixol > chlorpromazine > metoclopramide > thioridazine > clozapine > sulpiride. This ranking is roughly correlated with that based on clinical potencies. The relative elevation of the content of HVA was weaker in the pre-frontal cortex than in the caudate for all drugs tested, except clozapine at a high dose.  相似文献   
8.
Rewards are often not only valued according to their physical characteristics but also relative to other available rewards. The striatum (caudate nucleus, putamen, ventral striatum including nucleus accumbens) is involved in the organization of movement and the processing of reward information. We studied the activity of single striatal neurons in macaques that were presented with different combinations of two rewards. We found in nearly half of the investigated neurons that the processing for one reward shifted, relative to the other rewards that were available in a given trial block. The relative reward processing concerned all forms of striatal activity related to reward-predicting visual stimuli, arm movements and reception of rewards. The observed changes may provide a neural basis for the known shifts in valuation of rewarding outcomes relative to known references.  相似文献   
9.
The caudate lobe of the liver   总被引:3,自引:0,他引:3  
Summary The caudate lobe of the liver is an independent segment straddling the right and left lobes of the liver. It is divided into 2 parts, right and left, indicated eternally by the caudate and papillary processes. It is now possible to unvestigate it by ultrasonography and computed tomography, allowing its surgical excision for tumoral disease of the superior biliary confluence.
Le lobe caudé du foie

Résumé Le lobe caudé du foie est un secteur indépendant à cheval sur les foies droit et gauche. Il est séparé en 2 parties droites et gauches, marquées extérieurement par les processus caudé et papillaire. Son exploration est actuellement possible (échographie et tomodensitométrie), ce qui autorise son exérèse chirurgicale (pathologie tumorale du confluent biliaire supérieur).
  相似文献   
10.
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