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311.
Higher cerebral dysfunctions such as aphasia, apraxia and agnosia have seldom been reported in multiple sclerosis (MS). 12 year-old right-handed boy felt unsteadiness of the body and headache for several days. Two months later, he had the same episode and complained of visual disturbance, and weakness and sensory disturbance on the face and the extremities. Additionally, he showed amnestic aphasia, acalculia, ideomotor apraxia, finger agnosia and right-left disorientation. Cerebrospinal fluid examinations revealed increases IgG, myelin basic protein and neuron specific enolase (11%, 25 ng/ml and 28.8 ng/ml, respectively). X-ray CT scan and MRI-CT examinations revealed sclerotic lesions on the left parietal white matter and the right mid-brain. The diagnosis was made as MS. He was treated with m-PSL (methyl-prednisolone) pulse therapy for three weeks and consecutively treated with PSL for four weeks. He recovered gradually, but visual disturbance and facial palsy remained. After seven months MRI-CT showed a high signal intensity on the left parietal white matter in spite of the disappearance of the lesion on X-ray CT scan. We suggest that these higher cerebral dysfunctions may result from the lesion of the left parietal white matter which produces a disconnection between each cortical area.  相似文献   
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Three children with malignant primary CNS tumors treated with craniospinal radiotherapy developed intraparenchymal hemorrhages a median of 5 years following therapy in sites distant from the primary tumor. Radical surgical procedures disclosed fresh and old hematoma, gliosis, and necrosis in all 3 patients and an aggregation of abnormal microscopic blood vessels in two. No tumor was found. All 3 patients remain in long-term (greater than 10 years) continuous remission.  相似文献   
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It is shown that with the holding potentials (Eh) ranging from -50 to -30 mV the amplitudes of the inward Ca current of identified neurons are significantly higher in old (20-24 months) Lymnaea stagnalis molluscs than in adult ones.  相似文献   
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Single or combined monoclonal antibodies (McAbs) Zh53, Zh820, and Zh2-1 have been used to eliminate malignant clonogenic cells from human bone marrow. The test of cytotoxicity showed that all of these McAbs could express high specific cytotoxic action against HL-60 cells and were selectively complement-dependent cytotoxic to various types of fresh leukemic cells. Clonogenic assay detected that single treatment with antibody and rabbit complement (RC) could reduce clonogenic units of HL-60 cells by more than 2 logs and two treatments reduced clonogenic units by more than 4 logs. However, combination of 2 McAbs could reduce clonogenic units by 4-5 logs. The data suggest that multiple treatments with McAbs and RC or a combination of 2 McAbs are more effective than a single treatment in eliminating clonogenic tumor cells. Treatment of normal human bone marrow with Zh53, Zh2-1 and RC did not produce a loss of normal CFU-GM, but treatment with Zh820 reduced the clonic units of normal CFU-GM by 24%.
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Caisson disease of bone   总被引:2,自引:0,他引:2  
Caisson disease of bone, which may affect compressed air workers and divers, is characterized by regions of bone and marrow necrosis that may lead to secondary osteoarthrosis of the hip and shoulder joints. A review of the pathologic, radiologic, and clinical aspects demonstrated uncertainties in the exact etiology. Early diagnosis is often not possible because of the delayed appearance of radiologic abnormalities. Research into these two aspects of this condition was carried out by the Medical Research Council Decompression Sickness Research Team in Newcastle upon Tyne over a ten-year period (1972 to 1982). Because no suitable animal model exists for the study of this condition, bone and marrow necrosis was produced by embolism of bone blood vessels with glass microspheres. With this model, it was shown that the presence of bone and marrow necrosis could be detected by bone scintigraphy using 99mTc-MDP and by measuring changes in serum ferritin concentration at a much earlier stage than was possible by radiography. However, only the former method has proved useful in clinical practice. Investigations into the etiology of caisson disease of bone have shown evidence for an increase in marrow fat cell size resulting from hyperoxia. This phenomenon may play a role in the production and localization of gas bubble emboli, which are thought to be the cause of the bone and marrow necrosis.  相似文献   
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