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81.
The myelin-deficient mutant rat develops generalized tonic seizures and dies during the fourth postnatal week. Surgical constriction of the lower thoracic spinal cord, performed either after the seizures have appeared or before, eliminates the seizures, or delays their onset, and prolongs the life of the animals. These observations support the view that the seizures in these animals can be triggered by abnormal activity originating in the myelin-deficient spinal cord and can be blocked by preventing that activity from ascending to higher levels. Similar seizures and "paroxysmal" phenomena occur in other myelin-deficient conditions including multiple sclerosis.  相似文献   
82.
We monitored the blood pressure and pulse rate during routine excretory urography in 3002 patients (4832 examinations) using high osmolality contrast medium. After injection of contrast medium, the blood pressure was changed more than 20% of the pre-injection blood pressure lasting for more than 1 minute in 27 patients (27 examinations, 0.56%), including 8 patients with a hypertensive reaction (0.17%) and 19 patients with a hypotensive reaction (0.39%). In all 27 patients, transient tachycardia was seen along with the progress of blood pressure change. Bradycardia was associated with a severe hypotensive reaction in 2 patients. In 19 patients with a hypotensive reaction, the blood pressure was progressively decreased beyond 60 mmHg in 9 patients (0.18%) while the blood pressure was remained above 60 mmHg in 10 patients (0.21%). Treatment was not necessary in 8 patients with a hypertensive reaction as well as in 10 patients with a mild hypotensive reaction (above 80 mmHg). In these 18 patients, the examination would have been finished without a suspicion of the blood pressure change unless the blood pressure was monitored. In 9 patients with a severe hypotensive reaction (below 60 mmHg), the subjective or objective symptoms were present during the examination in 7 patients. They should be considered to have had "severe adverse reaction". In remaining 2 patients, there was no subjective or objective symptoms. We discussed possible mechanisms regarding the change of blood pressure and pulse rate after injection of contrast medium.  相似文献   
83.
The newly developed oxygenator "D702" is a compact hollow fiber membrane oxygenator with a priming volume of 170 ml. The maximum flow allowance is 4 liters per/minute. We used this oxygenator in 16 patients (11 infants and children, and 5 adults) undergoing various open heart surgery, and function of this oxygenator was studied. Pulsatile cardiopulmonary bypass was performed in 8 patients and nonpulsatile constant flow perfusion was employed in the remaining 8 patients. Our clinical experience showed excellent maintenance of PaO2 and PaCO2 during both pulsatile and constant flow bypasses. A low pressure drop was encountered across the membrane oxygenator, and therefore, this oxygenator is applicable for pulsatile cardiopulmonary bypass. The D702 is a very useful and applicable for a wide range of patients from infants to adults with a small body structure.  相似文献   
84.
In order to evaluate the clinical usefulness of indocyanine green video-angiography (IA), the angiographic features of choroidal neovascular membranes (CNM) were investigated in 27 eyes with choroidal neovascular diseases by means of standard fluorescein angiography (FA) and IA. FA showed the existence of CNM in 21 eyes and IA demonstrated evidence of CNM in 19 eyes, as "fan, comb or spotty hyperfluorescence" in the early stage and "leakage" in the late stage. In 6 out of 19 eyes the existence of CNM was shown by IA, while FA failed to identify the precise location and size of CNM due to the masking effect of overlying turbid fluid, massive hemorrhage or a large amount of serous fluid. The results imply that IA has an advantage over FA in cases where FA shows only the sign of occult choroidal neovascularization, and that IA can be applied to neovascular maculopathy as a routine examination.  相似文献   
85.
Patients with acute (2,569) and chronic (957) leukemia diagnosedat 19 institutes took part in the study on the "MultidisciplinaryTreatment of Leukemia" between 1971 and 1985 and were investigatedretrospectively. By dividing the 15 years into three five-yearperiods, we were able to compare patient ratios in the differentperiods. The proportions of acute to chronic leukemia casesshowed no obvious change; however, the proportions of casesdiagnosed as acute lymphocytic leukemia in acute leukemia showeda significant increase. The main chemotherapeutic drugs usedduring the three time periods were cytarabine or its analogues,the anthracyclines, 6-mercaputopurine and prednisolone, againstacute myelogenous leukemia, and the vinca alkaloids, prednisoloneand the anthracyclines against acute lymphocytic leukemia. Therate of complete remission from acute myelogenous leukemia mademarked progress, from 45.1% during 1971–1975 to 62.3%during 1981–1985, but that of acute lymphocytic leukemiashowed no significant progress, being 65% during 1971–1975and 69.7% during 1981–1985. The durations of remission,however, and the survival times for patients with acute lymphocyticleukemia, as well as for those with acute myelogenous leukemia,became significantly longer over the three periods. Median survivaltimes from chronic myelocytic leukemia were 37–40 mo inall three periods, showing no progress. There was a better prognosisin cases of chronic myelocytic leukemia with, than without,Philadelphia chromosome. Except for a low incidence of chroniclymphocytic leukemia in Japan, adult leukemia patients' characteristicsand prognoses seem to be almost the same in Japan as in theU.S.A. and Europe.  相似文献   
86.
Proliferative glomerulonephritis with proteinuria was induced in Wistar rats by bovine serum albumin (BSA). Rats were first immunized with 1 mg or 2.5 mg of BSA and complete Freund's adjuvant (GFA) and eight weeks later 1 mg of BSA were given intravenously six times a week for four weeks. Immunofluorescence revealed granular deposits of IgG, G3, and BSA in the mesangial area with or without deposition of the same components along the capillary wall. Evaluation of the circulating antibody disclosed an apparent correlation between the level of antibody and histological findings. Rats with an intermediate amount of antibody production developed mesangial widening with mesangial immune deposits and no proteinuria. Rats with a low response developed proliferative glomerulonephritis with immune deposits along the capilary wall as well as in the mesangial area and proteinuria.  相似文献   
87.
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89.
We describe the case of a 40-year-old man whose disease was initially diagnosed as acute myelocytic leukemia. The patient achieved remission with chemotherapy, but relapsed shortly afterwards with an acute T-cell lymphoblastic leukemia. He died of intracranial bleeding. Karyotyping analysis showed a del(9p?) as a common abnormality in the leukemic cells at onset and relapse. Fluorescence in situ hybridization analysis demonstrated allelic loss of the CDKN2A gene in cells from both stages of the disease. At relapse the leukemia cells had additional abnormalities such as add(1)(p36) and del(12)(p11). We postulate that the loss of CDKN2A is involved in leukemogenesis but does not determine the lineage of the leukemic cells. Instead, abnormalities of genes at 1p36, 12p11, or both may be involved in driving a lymphoid phenotype.  相似文献   
90.
BACKGROUND: A small number of malignant peripheral nerve sheath tumours (MPNSTs) are low grade, and the nature of these low grade tumours has never been systematically assessed. AIMS: To describe the clinicopathological, immunohistochemical, and ultrastructural features of low grade MPNST and to discuss the main differential diagnoses. METHODS: Four cases of low grade MPNST were studied, including one coexistent with neurofibromatosis type 1. The tumours were analysed with respect to nuclear atypia, cellularity, nuclear enlargement, hyperchromasia, mitotic rate, and necrosis. Immunohistochemistry was performed by standard techniques, and an ultrastructural study was performed on one tumour. RESULTS: The ages of the patients ranged from 32 to 72 years (mean, 58). Two were male and two were female. Three tumours occurred in the deep tissue, including one in the retroperitoneum, and one was located in the dermal and subcutaneous tissue. The maximum diameters of the tumours ranged from 3.5 to 8.0 cm. Microscopically, all tumours showed moderate hypercellularity, an increased nuclear to cytoplasmic ratio, and hyperchromasia, but exhibited varied growth patterns, including those that were atypical neurofibroma-like, low grade fibromyxoid sarcoma-like, low grade epithelioid, and haemangiopericytoma-like. All tumours showed immunoreactivity for S-100 protein and vimentin. CONCLUSIONS: These findings suggest that careful clinical and histological evaluation, along with S-100 protein immunostaining, are essential for the accurate diagnosis of low grade MPNST.  相似文献   
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