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Immunohistochemical and immunoelectron microscopical studies were carried out on 28 aged dogs' brains. Amyloid deposits were seen in the arteries and capillaries in the leptomeninges and in superficial areas of the cortices in 19 (67.9%) of the 28 dogs (10-22 years of age). Immunohistochemically, these amyloid deposits were reactive for anti-beta/A4 antibody. Additionally, a variable number of parenchymal deposits with diffuse beta/A4-immunoreactivity (diffuse plaques) was also noted throughout the cerebral cortex in 24/28 dogs (85.7%). However, these plaque lesions were undetectable in Congo red staining. Electron microscopically, amyloid fibrils, measuring 10 nm in width, were located mainly in the tunica media of the arteries, and in less involved vessels they tended to be present among collagen fibres in the adventitia and smooth muscle cells in the outer layer of the media. The plaque lesions appeared to contain sparse aggregations of amyloid fibrils. In immunoelectron microscopical examinations, all amyloid fibrils in both blood vessels and plaques were selectively labelled by gold particles. These findings indicate that aged dogs can provide a useful experimental model for research into the beta/A4-type of cerebral amyloidosis commonly seen in Alzheimer's disease.  相似文献   
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OBJECTIVE: To evaluate the initial results of brachytherapy for prostate cancer with permanent iodine-125 implant in Japan. METHODS: The results obtained with brachytherapy in the initial 100 Japanese patients treated at Nagano Municipal Hospital were reviewed. Patients with a prostate-specific antigen (PSA) level of less than 10 ng/mL and a Gleason's scores of 5, 6, 3 + 4 were classified as having a low risk of recurrence. Patients with a PSA level of 10-20 ng/mL and/or a Gleason's score of 4 + 3 were classified as having an intermediate risk for recurrence. Seventy-eight of the low-risk patients and 19 of the intermediate-risk patients were treated by seed implants alone, or seed implants combined with preceding external radiation, respectively. A total of 53 patients received neoadjuvant hormone therapy. The efficacy and morbidity of brachytherapy were investigated using the serum PSA, International Prostate Symptom Score, quality of life score and uroflowmetry data. RESULTS: The average V100 and D90 obtained by post-implant dosimetry was 94.3 and 113.7%, respectively. Serum PSA decreased gradually after treatment, although it had still not reached a nadir after 1 year. There was little difference of the PSA level between the patients with and without neoadjuvant hormone therapy even at 1 year after seed implantation. There were no PSA biochemical failure or clinical recurrence during the follow-up period. Voiding symptoms worsened until 3 months after treatment, and then gradually improved. Acute urinary retention occurred transiently in one patient (1%). Rectal bleeding and severe diarrhea did not occur. CONCLUSION: Brachytherapy is a feasible and effective option for the treatment of prostate cancer in Japanese men. Brachytherapy may have a different effect in Japanese patients with respect to voiding symptoms. Urinary retention was rare, but voiding symptoms were persistent in Japanese patients. Neoadjuvant hormone therapy deserves investigation to determine whether it can achieve better results, especially in patients with an intermediate risk.  相似文献   
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This paper describes a measure of explained variation (MEV) of survival times for a given regression model used in survival analysis. It quantifies the predictive power of a set of prognostic factors in the model, and therefore provides useful information for more precise prediction of patient prognosis, and for designing randomized clinical trials with the capability of determining treatment effects. The MEV defined in this article is asymptotically derived from the squared product-moment correlation; it can be interpreted as an adaptation of the multiple correlation coefficient for the normal linear model to the survival time regression model. Monte-Carlo simulations are performed to investigate the statistical behavior of the proposed MEV. The MEV is applied to estimate the predictive power of several sets of prognostic factors for gastric cancer in Japan using data from a large clinical trial.  相似文献   
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We present herein the rare case of a 48-year-old man in whom an abdominal mass, revealed by celiotomy to be a solid tumor of the mesoappendix, was histologically diagnosed as having a venous hemangioma. To our knowledge, only 18 cases of mesenteric hemangioma have been reported in Japan, including the present case. However, establishing a correct diagnosis preoperatively is extremely difficult despite advanced imaging techniques. In fact, a mesenteric mass was diagnosed preoperatively in only 3 of these 18 cases. Complete excision with or without bowel resection was performed in 16 cases. Interestingly, the histological diagnosis of all the previous cases was cavernous hemangioma, confirming that this report decuments the first case of venous hemangioma of the mesentery in the Japanese literature.  相似文献   
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A 51-year-old man with recurrent gastric cancer was treated by combined administration of Cisplatin and Carmofur. The target sites were the abdominal lymph nodes and the area of invasion to the stomach. Cisplatin (50 mg/body/day) was given for 3 days, while Carmofur (400-800 mg/body/day) was administered daily in 1 course. After 1 course of administration, the target tumor was reduced in size and the therapy was continued. A complete response was confirmed by upper gastrointestinal roentgenography, endoscopy and echography after 8 courses of Cisplatin administration. The patient has survived for 2 years 6 months in a state of CR. This case suggests that a combination therapy of Cisplatin and Fluoropyrimidine derivatives might be effective for gastric cancer.  相似文献   
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We report satisfactory results with a new operative treatment, conducted via an extensive anterolateral approach, involving 360 degree circumferential capsulotomy, for residual subluxation in congenital dislocation of the hip (CDH). Long-term radiographic results of this procedure (group A) were compared retrospectively with the results of partial capsulotomy (group B), which preserved the posteroinferior joint capsule. The mean center edge angle in group A (22.5°) was greater than that in group B (16.0°). Satisfactory results were achieved in 11 of 15 hips (73%) (Severin class I or II) in group A, and in 5 of 12 hips (42%) in group B. These results suggest that whole circumferential capsulotomy can remove obstacles to complete reduction, and that acetabular development can be expected in hips reduced by the procedure, without the performance of innominate osteotomy. We believe that our technique is a useful alternative for the treatment of residual subluxation in CDH.  相似文献   
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An analysis of subretinal fluid in bullous retinal detachment   总被引:1,自引:0,他引:1  
A patient with bilateral bullous retinal detachment underwent drainage of the subretinal fluid. The analysis of the subretinal fluid revealed a high protein concentration--17.4 g/dl OD, 27.5 g/dl OS--which was 3-5 times higher than that of the patient's serum. The protein fractionations of the subretinal fluid were almost the same as those of the serum. These findings may well explain the shifting fluid and support the theory that bullous retinal detachment is caused by the breakdown of retinal pigment epithelial function as a barrier between the choroid and retina.  相似文献   
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