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A 30-year-old female developed moyamoya syndrome after gamma knife surgery (GKS) for cerebral arteriovenous malformation (AVM), and was treated with bypass surgery. She suffered from flittering scotoma, right transient hemianopsia, and headache for 1 year. Cerebral angiography revealed a Spetzler-Martin grade III AVM located in the left occipital lobe. After staged embolization, GKS was performed with a minimum dose of 20 Gy to the periphery of the nidus at the 50% isodose level of the maximum target dose. Gradual nidus regression was achieved, and the clinical symptoms disappeared completely. However, at 30 months after GKS, the patient suffered transient ischemic attack. Cerebral angiography showed left middle cerebral artery occlusion with moyamoya vessels. The patient underwent direct and indirect bypass surgery. After surgery, the patient was free from ischemic symptoms. Chronic inflammation and long-term changes in expression of cytokines and growth factors after GKS may have triggered this case.  相似文献   
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The authors present a case of a ruptured anterior inferior cerebellar artery aneurysm at the right internal auditory meatus, the incidence of which is thought to be very rare. The patient experienced sudden onset of headache, vomiting, and right tinnitus. Moderate right peripheral facial paresis, hearing disturbance and diplopia appeared 2 weeks after the onset. These signs and symptoms improved to some extent after successful clipping of the aneurysmal neck.  相似文献   
76.
Effect of Antiepileptic Drugs on Absence-Like Seizures in the Tremor Rat   总被引:8,自引:1,他引:7  
Summary: We examined the effects of conventional antiepileptic drugs (AEDs) on absence-like seizures in homozygous tremor rats (tm/tm) to determine if they corresponded pharmacologically to human absence seizures and absence-like seizures in spontaneously epileptic rats (SER: zi/zi, tdtm) with both tonic convulsive and absence-like seizures. Cortical and hippocampal EEG activity was recorded with chronically implanted electrodes. The effects of AEDS on seizures of the tremor rat showed profiles similar to those observed in human absence seizures and also in absence-like seizures of SER. The absence-like seizures, associated with paroxysmal bursts of 5–7–Hz spike-wave complexes, were inhibited by trimethadione (TMO 200 mg/kg intraperitoneally, i.p.), ethosuximide (ESM100 and 200 mg/kg, i.p.), valproate (VPA100 mg/kg, i.p.), and phenobarbital (PB10 and 20 mg/kg, i.p.1. Phenytoin (PHT 20 mg/kg, i.p.) was ineffective. These results are consistent with the conclusion that the tremor rat is a useful model for evaluating new AEDS for human absence seizures.  相似文献   
77.
Background: In addition to its role in calcium and phosphorus metabolism, calcitriol (1,25-dihydroxyvitamin D; 1,25-D3) demonstrates multiple effects on cell proliferation/differentiation by expressing major histocompatibility complex (MHC) antigens and intercellular adhesion molecule-1 (ICAM-1). It has recently been reported that 1,25-D3 inhibits the growth of prostatic cancer (PCa) cells. In this study we examined the effect of 1,25-D3 on both the growth and expression of HLA-ABC, HLA-DR and ICAM-1 antigens in PCa cells.
Methods: Four human PCa cell lines (PC-3, PPC-1, ALVA-41 and ALVA-101) were examined. The cell numbers were enumerated, and the effects of interferon-y (IFN-y) and 1,25-D3 on the expression of HLA-ABC, HLA-DR and ICAM-1 were quantitated by flow cytometry.
Results: A dose-dependent antiproliferative effect of 1,25-D3 was found in all PCa eel Is lines except ALVA-41. 1,25-D3 was approximately 10 times as potent as its analogue 24,25-dihydroxyvitam in D3 in inhibiting the growth of PC-3 cells. Also, the relative inhibitory ability of these compounds paralleled the strength of their binding affinities for the 1,25-D3 receptor, indicating that the antiproliferative effect may require a receptor-ligand interaction. HLA-ABC was expressed in PC-3, ALVA-41 and ALVA-101, but not in PPC-1 cells, while HLA-DR was not expressed on any of the tested cells. IFN-y could enhance or induce HLA-ABC but not HLA-DR expression in the tested cells. ICAM-1 was expressed in all cells and slightly up-regulated by IFN-y.
Conclusion: In this study 1,25-D3 had an antiproliferative effect on 3 of the 4 examined PCa cell lines.  相似文献   
78.
Motor evoked potentials (MEPs) elicited by magnetic coil stimulation of motor cortex were studied at rest and during maximum voluntary muscle contraction in 20 normal subjects and 42 patients with motor disorders. MEP parameters employed in this study included: onset latency, amplitude, MEP/M wave amplitude ratio and background EMG/MEP area ratio. Maximum voluntary contraction increased the amplitude of MEPs compared to the size of M waves elicited by peripheral nerve stimulation. A reduced MEP/M wave amplitude ratio had a higher correlation with pyramidal tract involvement than did a prolonged MEP onset latency. Analysis of MEP parameters may help in the differential diagnosis of cerebral infarction, ALS and cervical spondylotic radiculomyelopathy. The inhibitory period which follows MEPs during voluntary contraction was observed in all subjects; the mean duration in normal subjects was 126.6 +/- 29.5 msec. The mean duration of the inhibitory period in patients with cerebral infarction, ALS and cervical spondylotic radiculomyelopathy was 73.9 +/- 41.7 msec, 79.5 +/- 54.5 msec and 85.1 +/- 36.5 msec, respectively. These values were significantly shorter than in normal subjects.  相似文献   
79.
Orbital apex syndrome is a symptomatologic complex. In this paper, the usefulness of several clinical diagnostic MR methods in preparing for surgery is discussed. These include dynamic MRI and the spoiled GRASS (SPGR) image for a cavernous sinus meningioma presenting with orbital apex syndrome. A 53 year old man, who had right cavernous sinus tumor presenting with orbital apex syndrome, was examined by several new MRI techniques. The tumor was partially removed and fibroblastic meningioma was confirmed pathologically.  相似文献   
80.
We describe spontaneous disappearance of an aneurysmal malformation of the vein of Galen (AMG), an anomaly that occurs most often in children, with a high mortality due to the accompanying severe cardiac failure. Spontaneous thrombosis of an AMG is rare. In this case, the AMG has been closed for about 5 years, without radiological evidence of thrombosis, and no active treatment. Proposed mechanisms of spontaneous thrombosis include slow flow shunts and severe obstruction of the venous outflow. However, in this case, the disappearance of the AMG without evidence of thrombosis indicates a different mechanisms, namely, obstruction of the feeding artery.  相似文献   
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