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91.
The interaction between oxyhemoglobin (oxyHb) and 5-hydroxytryptamine (5-HT) was investigated in an experimental model of isolated canine internal and common carotid arteries with insertion of stainless steel cannulae. Extraluminal application of 10(-5) M oxyHb induced marked and long-lasting vasoconstriction in the internal carotid but not in the common carotid arteries. The 5-HT-induced vasoconstriction was potentiated significantly in both the internal and common carotid arteries. These potentiations were not influenced by the presence or absence of endothelium, a finding which was confirmed by vascular responses to intraluminal acetylcholine. It is concluded that the interaction between extraluminal oxyHb and intraluminal 5-HT may be one of the possible etiological factors behind the chronic phase of vascular spasm following subarachnoid hemorrhage.  相似文献   
92.
A 66-year-old woman time of 10 days. One month after radicalmastectomy, there was local recurrence, followed by multiplepulmonary metastases, and the patient died of respiratory failure5 months after surgery. The gray-white-colored tumor measured13x12x;10 cm, and its border was well defined. The tumor wascomposed of diffusely growing round or polygonal cells withvesicular nuclei, prominent nucleoli, and ample cytoplasm containingeosinophilic inclusions. Lymph node involvement was widespread.Both vimentin and keratin were clearly demonstrated by immunohistochemicalstaining. Ultrastructural studies revealed that the MRT cellscontained cytoplasmic whorls of intermediate filaments.  相似文献   
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We report here an unusual case of fibrous histiocytoma in which an area of xanthogranuloma was observed histologically. Our case suggests that adult xanthogranuloma is a variant of fibrous histiocytoma.  相似文献   
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A 60-year-old man suffered from paraplegia after the operation for thoracic aortic aneurysm and died 10 months after the operation. Detailed examination on the distribution of spinal cord lesions and of the locations of anterior radicular arteries revealed that the spinal cord ischemia occurred at the mid-thoracic segments between T-6 and T-10; the artery of Adamkiewicz entered at T-12; another radicular artery entered at T-4. We concluded that the spinal cord ischemia was caused by the interruption of the radicular artery at T-4 and that the segments nourished by the blood flow of the artery of Adamkiewicz were intact. We suggest that in some patients important radicular arteries other than the artery of Adamkiewicz are essential to preserve blood flow to the upper or middle thoracic spinal segments.  相似文献   
97.
Anorectal function was evaluated in eight patients who had low anterior resection of the rectum with a low anastomotic line, using an EEA stapler, with determination of function based on periodic manometric studies and clinical symptoms. Immediately following surgery all patients suffered from frequent bowel actions and soiling. These symptoms improved with time and most patients could enjoy almost normal daily life by the sixth postoperative month. One month after surgery, anal canal resting pressure and maximum squeeze pressure were significantly reduced and rectoanal inhibitory reflex was absent; neither showed a distinct tendency to improve thereafter. Rectal sensation and reservoir capacity, which also were seriously impaired, recovered satisfactorily by the time of the six-month examination. This suggests that an improvement of clinical symptoms following this operation is dependent upon the recovery of reservoir capacity and sensation of the neorectum, and that this operative procedure is a functionally acceptable option for low rectal cancer.  相似文献   
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