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51.
52.
The current study aims to determine the associations of insufficient sleep with suicide attempts and self-injury in a large, school-based Korean adolescent sample.  相似文献   
53.
The 53 kDa insulin receptor substrate protein (IRSp53) is highly enriched in the brain. Despite evidence that links mutations of IRSp53 with autism and other neuropsychiatric problems, the functional significance of this protein remains unclear. We used light and electron microscopic immunohistochemistry to demonstrate that IRSp53 is expressed throughout the adult rat brain. Labeling concentrated selectively in dendritic spines, where it was associated with the postsynaptic density (PSD). Surprisingly, its organization within the PSD of spiny excitatory neurons of neocortex and hippocampus differed from that within spiny inhibitory neurons of neostriatum and cerebellar cortex. The present data support previous suggestions that IRSp53 is involved in postsynaptic signaling, while hinting that its signaling role may differ in different types of neurons. J. Comp. Neurol. 522:2164–2178, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   
54.
Hashimoto’s encephalopathy (HE) is a rare neurological disorder. Early diagnosis and treatment are critical to prevent irreversible brain damage. In the present study, we aimed to describe and classify HE on the basis of clinical, neuroimaging, and EEG findings. We retrospectively reviewed the clinical, radiological, and electrophysiological findings in patients who showed both neurological symptoms and high titers of anti-thyroid antibodies, and who were admitted between 2006 and 2012. Our patients were classified into two groups: those presenting seizures (group 1) and those with diffuse encephalopathies (group 2). Group 1 contained two patients. Patient 1, who showed verbal memory disturbance, focal MRI lesions, and partial seizure activity on EEG, recovered with antiepileptic and steroid treatments. Five of six patients assigned to group 2 were treated with steroids and showed significant improvement. One patient treated with azathioprine showed moderate improvement. Four of these patients had accompanying metabolic disturbances. HE is a treatable neurologic disorder with different subtypes, each with its own clinical manifestations and treatment options. HE can be difficult to identify and requires careful and attentive clinical observation for diagnosis.  相似文献   
55.
56.

Introduction

Alveolar soft part sarcoma (ASPS), a rare soft tissue malignant neoplasm, frequently metastasizes to the brain. However, primary intracranial ASPS is extremely rare. We present a case of primary intracranial ASPS arising from the cerebellopontine angle (CPA) without demonstrable systemic lesions.

Case report

An 11-year-old girl presented with a recurrent tumor in the right CPA after a partial resection and radiation therapy (RT). Near-total resection with a minimal tumor left in the jugular foramen was performed. The pathological diagnosis was ASPS. There was no evidence of primary extracranial tumors. She underwent adjuvant chemotherapy and gamma knife surgery. At 29 months after the second surgery, magnetic resonance imaging revealed multifocal enhancing lesions at the prepontine cistern, right CPA and medulla oblongata, despite intensive treatment. However, extracranial metastasis was not noted. This case suggested a poor outcome of primary intracranial ASPS, similar to extracranial ASPS.  相似文献   
57.
Cognitive dysfunction constitutes a major non-motor manifestation of Parkinson disease (PD), but the mechanisms remain incompletely understood. Neurocirculatory abnormalities such as supine hypertension (SH) and orthostatic hypotension (OH), white matter hyperintensities upon magnetic resonance imaging, and dementia are inter-related in PD, even in patients with early, levodopa-untreated disease. These abnormalities might in turn be associated with carotid atherosclerosis which, by a variety of interacting means could contribute to repeated episodes of cerebral hypo- and hyper-perfusion. We investigated inter-correlations among neurocirculatory and carotid sonographic measurements [intimal-medial thickness (IMT) and wall:lumen ratios (WLR)] in 65 patients with levodopa-untreated, de novo PD who underwent tilt table testing and 24-h ambulatory blood pressure monitoring. Increased mean IMT and WLR were associated with OH and supine and overnight blood pressures. Across individuals the orthostatic fall in systolic pressure was correlated with both IMT and WLR. Since arteriosclerosis would be expected to splint carotid sinus baroreceptors, complex positive interactions among carotid wall thickening, SH, and OH may result in myriad episodes of cerebral hypo- and hyper-perfusion, contributing to microvascular injury and consequently to the cognitive dysfunction attending PD.  相似文献   
58.
The aim of this study was to evaluate whether contrast enhanced fluid attenuated inversion recovery (CE-FLAIR) imaging can be used to predict the severity of meningitis based on leptomeningeal enhancement (LE) score and cerebrospinal fluid signal intensity (CSF-SI) on CE-FLAIR. We retrospectively analyzed data collected from 43 consecutive patients admitted to our hospital due to meningitis. Clinical factors including initial Glasgow Coma Scale (GCS) score, CSF glucose ratio, log CSF protein, log CSF WBC, and prognosis were evaluated. The LE score was semi-quantitatively scored, and we evaluated CSF-SI ratio at the interpeduncular or quadrigerminal cisterns on CE-FLAIR. We evaluated the differences in clinical variables, LE scores and CSF-SI ratios between the recovery and the complication group. We assessed the correlation between clinical variables, LE scores and CSF-SI ratios. The values of log CSF protein, CSF-SI ratio, and LE score were significantly higher in the complication group (p value <0.05). GCS score and CSF glucose ratio were significantly lower in the complication group (p value <0.01). The LE scores had significant negative correlation with GCS scores and CSF glucose ratios (p value <0.001). The LE score was significantly positively correlated with the value of log CSF protein and CSF-SI ratio (p value <0.01). The CSF-SI ratio was negatively correlated with GCS score and CSF glucose ratio (p value <0.01). The CSF-SI ratio was positively correlated with the value of log CSF protein (p value <0.05). Our results suggest that LE score and CSF-SI ratio are well correlated with clinical prognostic factors. We may predict the clinical severity of meningitis by using LE scores and CSF-SI ration on CE-FLAIR imaging.  相似文献   
59.
Koo JS  Seong JK  Park C  Yu DY  Oh BK  Oh SH  Park YN 《Intervirology》2005,48(1):16-22
OBJECTIVES: Large liver cell dysplasia (LCD) is frequently associated with hepatitis B virus (HBV), but it remains uncertain whether it is reactive, senescent or preneoplastic. METHODS: The HBX transgenic mice and normal control mice were sacrificed at 1, 3, 5, 7, 9, 11, 13 and 15 months after birth. Twenty-three cases of human B viral chronic hepatitis/cirrhosis with prominent LCD were selected. The immunohistochemical stain of proliferating cell nuclear antigen (PCNA), transferase-mediated dUTP-biotin nick end labeling (TUNEL) assay and senescence-associated beta-galactosidase (SA-beta-Gal) were evaluated. RESULTS: In HBX transgenic mice, LCD was developed since 3 months and formed small nodules of hepatocellular adenoma, which progressed to hepatocellular carcinoma. The hepatocytes with LCD in HBX transgenic mice showed significantly higher PCNA-labeling index (LI) and lower TUNEL-LI than normal hepatocytes of control mice (p < 0.05). In the majority of human B viral chronic hepatitis/cirrhosis, the hepatocytes with LCD revealed higher PCNA-LI and lower TUNEL-LI than those without, when compared in each case using the same tissue block. SA-beta-Gal staining showed no difference between hepatocytes with and without LCD. CONCLUSION: It is suggested that LCD, related to HBV, might not be just an innocent bystander, but closely related to hepatocarcinogenesis.  相似文献   
60.
Introduction: Patients with hereditary neuropathy with liability to pressure palsies (HNPP) manifest with episodes of focal paresis when exposed to mechanical stress, although the basis for vulnerability to conduction block remains relatively unexplained. Methods: Axonal excitability techniques were utilized to provide insights into pathophysiological mechanisms in 13 HNPP patients, stimulating median motor and sensory axons at the wrist. Results: In HNPP, distal latencies were prolonged, and motor and sensory amplitudes were reduced. Threshold was increased. Depolarizing and hyperpolarizing electrotonus was greater, and resting current–threshold slope was reduced. There were greater threshold changes in superexcitability, and refractoriness was decreased. Conclusions: Taken together, excitability testing in patients with HNPP established axonal hyperpolarization in both motor and sensory axons that may be attributable to changes in nerve architecture. In turn, the hyperpolarized resting membrane potential in HNPP may be a major predisposing factor for development of conduction block with mechanical stresses. Muscle Nerve 49 : 858–865, 2014  相似文献   
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