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1.
We studied two patients which showed a paralysis of the oculomotor nerve on one side and isolated paralysis of the superior rectus on the other side. On the side of oculomotor nerve paralysis, midbrain infarct extending from the paramedian tegmentum to crus cerebri was demonstrated in one case who showed no recovery, and a small lacuna in midbrain tegmentum in another one who showed complete recovery. On the side of isolated paralysis of the superior rectus, no lesion was demonstrated by CT and MRI, and no clinical signs of the involvement of fiber tracts or nuclei were evident in both cases. A unilateral lesion of oculomotor nerve nucleus caused a paralysis of the contralateral superior rectus.  相似文献   
2.
A new method for producing temporary complete cerebral ischemia in rats   总被引:2,自引:0,他引:2  
A new model of temporary complete cerebral ischemia was developed and tested in 64 rats. With use of microsurgical techniques, both pterygopalatine and external carotid arteries were occluded and the basilar artery was coagulated to reduce potential collateral CBF during ischemia. After this preliminary five-vessel occlusion, temporary global ischemia was induced by occluding the common carotid arteries (CCAs) with microclips. To validate the method, CBF was measured autoradiographically in 24 anatomical regions at death after 5 min of ischemia or after 15 min of ischemia followed by 5 min of reperfusion. Mean arterial blood pressure and arterial blood gases remained stable under controlled endotracheal ventilation and anesthesia (halothane, 70% N2O, and 30% O2) throughout the CBF experiments, except for a 10-15% increase in mean arterial blood pressure for 1-5 min after bilateral CCA occlusion. After the initial five-vessel occlusion, the EEG did not change, and local CBF levels were comparable to those in anesthetized non-surgical controls. When the CCAs were occluded, the EEG flattened rapidly; after 5 min of ischemia, autoradiography showed no detectable blood flow in the forebrain and cerebellum. The local CBF levels measured after 15 min of temporary global ischemia and 5 min of reperfusion demonstrated relatively homogeneous postischemic hyperperfusion; only two of eight rats had several 1- to 3-mm areas of no-reflow. Survival studies showed increasing motor impairment after 10, 15, 30, and 60 min of temporary CCA occlusion. Ischemic neuronal damage was observed histologically in the hippocampus and basal ganglia 24 h after 10 min of temporary ischemia.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
3.
It is well known that primary hyperparathyroidism is often associated with peptic ulcer. The purpose of this study is to confirm the relationship between the gastrin-levels before and after parathyroidectomy in fourteen patients with primary hyperparathyroidism, and to determine the localization of gastrin in the surgically resected parathyroid tumor. The results obtained were as follows: 1) Three patients had peptic ulcer (gastric ulcer and duodenal ulcer), the incidence being 21%. 2) The basal serum gastrin levels were 123.0% +/- 68.1 pg/ml before operation and decreased to 90.2 +/- 44.5 pg/ml after operation. In the 3 patients with slightly elevated gastrin levels, the mean level before operation was 209.1 +/- 61.2 pg/ml. The gastrin level decreased to 116.4 +/- 62.0 pg/ml after operation. 3) Gastrin immunoreactivity was detected in 10 out of 14 tumors and its localization was at the periphery of tumor cells. From these results, we conclude that extragastric gastrin secretion from parathyroid tumors may be one of the cause of peptic ulcer in patients with primary hyperparathyroidism.  相似文献   
4.
We examined the involvement of GABAergic neuronal systems in benzodiazepine-induced passive avoidance deficit. Chlordiazepoxide impaired the passive avoidance response dose dependently when it was given prior to training. Post-training administration of muscimol improved the performance of chlordiazepoxide-pretreated mice. The effects of muscimol were antagonized completely by the GABAA antagonist, bicuculline, and the muscarinic acetylcholine receptor antagonist, scopolamine, but not by the benzodiazepine receptor antagonist, flumazenil, when the latter was administered immediately after training. It appears from these results that the GABAergic neuronal system plays an important role in the benzodiazepine-induced passive avoidance deficit by interacting with the cholinergic neuronal system.  相似文献   
5.
The effects of N-(2,6-dimethyl-phenyl)-2-(2-oxo-1-pyrrolidinyl) acetamide (DM-9384), a new pyrrolidone derivative, were investigated on ethanol- and chlordiazepoxide (CDP)-induced amnesia animal model using the passive avoidance task in comparison with aniracetam, another pyrrolidone derivative. Pretraining administration of DM-9384 attenuated ethanol- and CDP-induced amnesia, whereas aniracetam failed to do so. The effects of DM-9384 on CDP-induced amnesia were antagonized by bicuculline, a GABAA receptor antagonist, but not by scopolamine, a muscarinic acetylcholine receptor antagonist and flumazenil, a benzodiazepine receptor antagonist. These results suggest that DM-9384 attenuates CDP-induced amnesia by interacting with the GABAergic neuronal system.  相似文献   
6.
Serum lipid and apolipoprotein concentrations were measured in 37 male survivors of cerebral infarction (CI) and in 30 healthy controls. Both groups had similar total cholesterol levels, but the HDL-cholesterol level was significantly lower and the serum triglyceride level was significantly higher in the CI patients than in the controls. The ApoB level was significantly higher in the CI patients but there was no significant difference between the 2 groups in the levels of the other apolipoproteins (ApoA-I, A-II, C-II, C-III, and E). The HDL-cholesterol/ApoA-I ratio was significantly lower in the CI patients. Both the VLDL-triglyceride and VLDL-cholesterol levels were higher in the CI patients but the VLDL-cholesterol especially its cholesterol ester level was conspicuously high. A population of VLDL particles that bound to heparin on heparin-Sepharose columns was increased in the CI patients. We suggest that cholesterol ester is excessively transferred from HDL to VLDL during the disturbed catabolism of VLDL in CI patients.  相似文献   
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A 67-year-old male diagnosed clinically as having rheumatoid pleuritis and bronchiolitis was treated with adrenocorticosteroid. His clinical findings improved, but following the tapering of the steroid dose, exacerbation occurred. After the steroid dose was increased, serological findings improved, but chest X-ray findings revealed no improvement. To re-evaluate the etiology of the bronchiolar lesion, open lung biopsy was performed. The biopsy specimen showed lymphocytic infiltration and formation of lymphoid follicles in and around the bronchioles. The pulmonary lesion was diagnosed as follicular bronchiolitis.  相似文献   
10.
We investigated the effects of vinconate, a novel vinca alkaloid, on spatial learning deficits induced by the basal forebrain (BF) lesion in rats. Bilateral BF lesions were produced by injecting ibotenic acid (6 micrograms/0.5 microliter/side). In BF-lesioned rats, impairment of spatial learning in escaping onto the platform during training and decrease in spatial bias during the spatial probe trial in Morris's water maze task were both observed. Vinconate (5 and 10 mg/kg) treatment shortened the increase of escape latency to the platform in BF-lesioned rats and significantly reversed the decrease in spatial bias induced by the BF lesion. Vinconate (10 mg/kg) attenuated the decrease in choline acetyltransferase activity in the frontoparietal cortex caused by the BF lesion. The present study suggests that vinconate has an antiamnesic effect on the BF-lesion-induced amnesia by ameliorating the dysfunction in cholinergic neurons.  相似文献   
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