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21.
(Received for publication on Oct. 6, 1997; accepted on July 7, 1998)  相似文献   
22.
We describe herein the case of a 51-year-old woman in whom metastatic tumor seeding of the percutaneous transhepatic biliary drainage tract occurred following a pancreatoduodenectomy for carcinoma of the distal common bile, duct. An abdominal computed tomography scan done 6 months after the initial operation detected a hepatic lesion located at the site of the previous percutaneous transhepatic biliary drainage tract. Implantation of bile duct carcinoma in the drainage tract was diagnosed, and the recurrent tumor was successfully resected by performing a subsegmentectomy of segment 3 and removal of the adjacent abdominal wall. At present, 5 years and 4 months after the second resection, the patient is in good health without any signs of recurrence. This case report demonstrates that an aggressive surgical approach should be performed for tumor seeding of a transhepatic biliary catheter tract.  相似文献   
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24.
To investigate the adequate extent of esophagectomy and lymphadenectomy for an esophageal cancer localized at the cervicothoracic junction, the mortality and morbidity rates, survival rates, and patterns of recurrence were retrospectively analyzed in two groups—14 patients who underwent total esophagectomy with or without laryngectomy and 15 patients who underwent proximal esophagectomy with or without laryngectomy—at Kurume University Hospital from 1981 to 1996. Proximal esophagectomy with or without laryngectomy resulted in a lower hospital mortality rate and better overall survival for patients who underwent curative esophagectomy compared with total esophagectomy with or without laryngectomy. Multivariate analysis indicated that the extent of esophagectomy (total esophagectomy versus proximal esophagectomy) was not a prognostic factor. The incidence of recurrence was not different between the two groups. Lymph node metastasis or recurrence from such esophageal cancers was localized to the neck and upper mediastinum. For an esophageal cancer localized at the cervicothoracic junction, therefore, proximal esophagectomy with or without laryngectomy and with cervical and upper mediastinal lymphadenectomy could be better indicated for preselected patients.  相似文献   
25.
The emergence rate and adult survival (longevity) of Japanese strains of Culex pipiens molestus and Culex quinquefasciatus were compared at temperatures of 21, 25, and 30 degrees C. The pupation and emergence rates in both strains were higher at 21 and 25 degrees C than at 30 degrees C. The adult emergence rate, especially in females, was lower in Cx. p. molestus than in Cx. quinquefasciatus. Longevity of females and males was lower in Cx. p. molestus at 25 degrees C and above. The survival of Cx. p. molestus was adversely affected by temperatures of 28 degrees C and higher. High temperature may restrict the distribution of this species. Therefore, if Cx. p. molestus infests the Okinawa region, the likelihood that it will become established is minimal.  相似文献   
26.
1 We utilized a rat model of myocardial infarction to investigate whether cardioprotection by monophosphoryl lipid A (MLA) is provided in the early and late phases, as well as to determine whether this cardioprotection may be related to the activation of manganese superoxide dismutase (Mn-SOD), an intrinsic radical scavenger. 2 Pretreatment with MLA (0.5 or 1.0 mg kg-1, i.v.) 24 h prior to 20-min left coronary artery (LCA) occlusion and 48-h reperfusion significantly decreased the incidence of ventricular fibrillation (VF) during ischaemia, as well as infarct size. Pretreatment with lower concentrations of MLA, however, was ineffective. 3 When we examined the time course of MLA (0.5 mg kg-1)-induced cardioprotection, both infarct size and the incidence of VF were significantly reduced in rats pretreated with MLA 0.5 h and 24 h before occlusion. We observed no differences, however, 2 and 72 h after MLA treatment. 4 The activity of Mn-SOD paralleled the cardioprotective effects of MLA. Mn-SOD activity in the myocardium was significantly enhanced in rats pretreated with MLA (0.5 mg kg-1) 0.5 and 24 h before. Mn-SOD activity was not altered, however, in rats pretreated 2 or 72 h before. Lower MLA concentrations were not effective even 24 h after the treatment. 5 We conclude that MLA treatment induced a biphasic pattern of cardioprotection. The pattern of Mn-SOD activity suggests that this enzyme may play a major role in the acquisition of cardioprotection against ischaemia-reperfusion injury.  相似文献   
27.
PURPOSE: To assess the predisposing factors and clinical characteristics of pelvic insufficiency fractures (PIF) in postmenopausal women with pelvic irradiation. MATERIAL AND METHODS: A total 335 postmenopausal patients with cervical cancer of the intact uterus treated with radiation therapy between 1983 and 1998 were reviewed. Total external dose was delivered between 45 and 50.4 Gy with parallel opposed anteroposterior portals. Total brachytherapy dose at point A was delivered between 10 and 36 Gy. PIF were diagnosed by bone scintigraphy and confirmed by computed tomography. The cumulative incidence of symptomatic PIF was estimated by actuarial methods. Potential risk factors (age, weight, type II diabetes, delivery, menopause, total external dose, total brachytherapy dose) were assessed. RESULTS: Fifty-seven (17.0%) of 335 patients were diagnosed as having PIF. Forty-seven patients were symptomatic and ten were asymptomatic. Parameters carrying a significant association with PIF were body weight 49 kg or below (P=0.044) in stepwise logistic regression analysis. The cumulative incidence of symptomatic PIF at 5 years was 17.9% calculated by the Kaplan-Meier method. A body weight of 49 kg or below and more than three deliveries were identified as having a significant effect on symptomatic PIF in univariate analysis (P=0.021, P=0.003, log-rank test) and Cox life table regression analysis (P=0.038, P=0.013). Five patients required narcotic agents and eight patients required hospital admission. CONCLUSIONS: We should consider reducing the dose contribution to the sacrum and sacroilac joints, without underdosing the tumor, especially in postmenopausal women with many deliveries or low body weight.  相似文献   
28.
A 72-year-old Japanese woman, suffering from squamous cell lung cancer with brain metastasis, underwent 2 courses of combination chemotherapy, consisting of cisplatin and vindesine. Although both the primary tumor and the brain metastasis regressed markedly, she developed left ocular pain with blurred vision. An abnormal mass was found in the left iris, and cytologic examination of the aqueous aspirate revealed a few malignant cells, which, when examined by electron microscopy, were considered to be derived from squamous cell carcinoma of the lung.  相似文献   
29.
We examined photoparoxysmal responses (PPRs) elicited by half-field visual stimulation with deep-red flicker light to determine the neurophysiological features of photosensitive epilepsy (PSE). EEG revealed two types of PPRs. One had the focal spike in the occipital region and the other in the temporo-occipital region at the contralateral hemisphere. The equivalent current dipoles of these types were located at the occipital cortex and the inferior temporal (IT) cortex, respectively. These cortices comprise one of the main pathways in the visual system, and they play important roles in color discrimination. Thus, we propose that the visual system, especially the occipital cortex and the IT cortex, might be involved in the generator mechanism of PSE.  相似文献   
30.
Watershed infarction associated with dementia and cerebral atrophy   总被引:5,自引:0,他引:5  
A 63-year-old man was admitted with progressive left hemiparesis and left homonymous hemianopsia of 1 month's duration. During the 2 months before admission, he had suffered from slowly progressive dementia. The diagnosis of right-sided watershed (WS) infarction was made. He exhibited slow progression of dementia and cerebral atrophy during the period of observation after discharge. There was a positive relationship between cerebral atrophy and the degree of dementia. In the present case, WS infarction caused by right internal carotid artery occlusion might be related to dementia and cerebral atrophy.  相似文献   
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