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31.
Temperature changes and their distribution induced by 13.56-MHz radiofrequency (RF) heating of agar phantom and porcine and rabbit liver were investigated. It was possible to produce selective local heating of approximately 50 degrees C in the RF field of 2 x 2 x 2 cm(3) of the pig or rabbit liver. Coagulation necrosis after heating became pronounced and the margin between the coagulated lesion and normal tissue became clearer with time. Within 1 week after RF heating at 50 degrees C for 20 min, the coagulated area was replaced selectively and totally by necrotic tissue.  相似文献   
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BACKGROUND: Symptoms of ischemic attacks in the internal carotid system usually involve focal cerebral dysfunction, i.e., hemiparesis or aphasia. However, an ischemic attack in the vertebrobasilar artery system usually presents with combined symptoms. The variety of manifestations included in the vertebrobasilar profile makes the potential pattern of symptoms considerably more variable and complex than that in the carotid system. Manifestations can include syncope and also vertigo. METHOD AND RESULTS: A 42-year-old woman experienced frequent attacks of faintness with vertigo. Angiography demonstrated severe stenosis of the left internal carotid artery with a persistent primitive hypoglossal artery just distal to the stenosis. The right internal carotid artery was normal and cross circulation through the anterior communicating artery was not well developed. Both vertebral arteries were hypoplastic. The patient underwent carotid endarterectomy and, thereafter the episodes of syncope completely disappeared. CONCLUSION: It was supposed that global ischemia including the brain stem occurred because of stenosis of the left internal carotid artery attributable to the presence of a primitive hypoglossal artery.  相似文献   
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We report the case of primary hepatic carcinoid tumor of which diagnosis was made by fine needle biopsy of a liver mass. The patient was treated successfully by left hepatic trisegmentectomy. This patient presented with complaints of generalized fatigue, but denied the presence of flushing, diarrhea, or other endocrine symptoms. Physical examination was unremarkable. A biopsy specimen revealed Grimelius stained cells that were immunoreactive for chromogranin A. Careful pre- and intraoperative examinations revealed no other primary lesions. Argyrophilia of the tumor cells suggested that the tumor was of fore five cases of primary hepatic carcinoid tumors previously reported in the literature are also reviewed.  相似文献   
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BACKGROUND: Intrapulmonary arteriovenous shunting (IPS), occasionally associated with advanced liver disease, may reverse after liver transplantation (LTx). Two-dimensional contrast-enhanced echocardiography, a convenient noninvasive study, has never been used to demonstrate disappearance of IPS after LTx. METHODS: For an 8-month-old girl undergoing living-related LTx, two-dimensional contrast-enhanced echocardiography was performed with the microbubble injection. The opacification of the microbubble in the left heart emerging within 3-6 beats after detection in the right heart was compared with that in the right heart. RESULTS: Microbubble opacification in the left heart was almost the same as that in the right heart (grade 3) shortly after LTx. However, the contrast in the left heart diminished (grade 1) as the respiratory condition improved and subsequently disappeared (grade 0). CONCLUSIONS: Two-dimensional contrast-enhanced echocardiography may be a feasible noninvasive method to evaluate the degree of IPS in the peritransplant period and observe disappearance of IPS after LTx.  相似文献   
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It has been controversial whether cancer cells harboring loss or inactivation of the tumor suppressor p53 are resistant or sensitive to DNA-damaging agents including cisplatin and doxorubicin. Overexpression of mdm2 oncoprotein, a negative regulator of p53, is assumed to be an alternative to p53 dysfunction. Archival urothelial carcinoma specimens obtained from 60 patients prior to cisplatin-based chemotherapy were immunohistochemically studied for overexpression of p53 and mdm2. Thirty-two patients (group I) were treated with chemotherapy in the neoadjuvant setting, while 28 patients (group II) underwent chemotherapy for distant metastases or inoperable locoregional tumors. In group I, the responsiveness was correlated with staining status of p53 ( P =0.0225) and the combination of p53 and mdm2 ( P =0.0497). Negative staining of p53 and negative for both p53 and mdm2 could have predicted favorable response to chemotherapy in 16 of 18 (88.9%) and in 12 of 13 (92.3%) tumors, respectively. On the other hand, p53-positive and p53 and/or mdm2-positive staining could have predicted poor response only in 7 of 14 (50.0%) and 8 of 19 (42.1%) tumors, respectively. Disease-specific survival of the p53-negative group was significantly superior to that of the p53-positive group ( P =0.0086). Difference in survival did not become more significant when overexpression of mdm2 was taken into consideration ( P =0.0456). In contrast, in group II, there was no correlation of responsiveness to chemotherapy or survival with p53- or p53/mdm2-staining status. The patients with urothelial carcinomas negative for overexpression of p53 will benefit from neoadjuvant chemotherapy. From clinical viewpoint, however, p53 status alone or the combination of p53 and mdm2 status is not enough to identify those patients who will not benefit from the treatment.  相似文献   
37.
We present a set of nuclear DNA SNPs useful for discriminating native Lake Biwa and introduced ??Eurasian?? strains of common carp, and further, for detecting their hybridization. Such SNPs were searched around short tandem repeat (STR) regions to be used later as HapSTR markers. A total of 62 microsatellite locus were screened with PCR and direct sequencing. The resultant nucleotide sequences from typical Lake Biwa (n?=?30) and ??Eurasian?? (n?=?24) specimens indicated that a total of 21 SNPs distributed across 7 loci would be useful for the above-mentioned purpose. All of the SNPs can be genotyped by direct sequencing, simultaneously with STR polymorphisms.  相似文献   
38.
Fatigue is a common complaint among medical students and researchers consider it to be related to poor academic outcomes. The authors' goal in the present study was to determine whether stress and coping strategies were associated with fatigue in medical students. The study group consisted of 73 second-year healthy students attending the Osaka City University Graduate School of Medicine. Participants completed a questionnaire about fatigue (Japanese version of Chalder Fatigue Scale), stress, stress coping (Japanese version of the Coping Inventory for Stressful Situations), overwork, and nocturnal sleeping hours. On univariate and multivariate logistic regression analyses adjusted for age and gender, stress was positively associated with fatigue. In addition, after adjustment for age, gender, and emotion- and task-oriented stress coping activities, avoidance-oriented stress coping activity was associated with fatigue. The results suggest that stress and the coping style are correlated with fatigue in medical students.  相似文献   
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