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81.
The effect of graft-versus-host disease (GVHD) on relapse incidence and survival has been analyzed in several studies, but previous studies included heterogeneous patients. Therefore, we analyzed the data of 2114 patients who received unmanipulated bone marrow graft from an HLA-identical sibling donor with a GVHD prophylaxis using cyclosporin A and methotrexate. Among the 1843 patients who survived without relapse at 60 days after transplantation, 435 (24%) developed grade II-IV acute GVHD. Among the 1566 patients who survived without relapse at 150 days after transplantation, 705 (47%) developed chronic GVHD. The incidence of relapse was significantly lower in patients who developed acute or chronic GVHD, but disease-free survival (DFS) was significantly inferior in patients who developed acute GVHD. A benefit of 'mild' GVHD was only seen in high-risk patients who developed grade I acute GVHD. The strongest association between GVHD and a decreased incidence of relapse was observed in patients with standard-risk acute myelogenous leukemia/myelodysplastic syndrome. In conclusion, the therapeutic window between decreased relapse and increased transplant-related mortality due to the development of GVHD appeared to be very narrow.  相似文献   
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83.
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   
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85.
The present study was initiated to examine the quantitative relationship between blood lead (Pb-B) and urinary delta-aminolevulinic acid (ALA-U) among Pb-exposed workers, and to find a threshold Pb-B level to induce an increase in ALA-U. For this purpose, pairs of venous blood and spot urine samples were collected from 8,274 men and 5,856 women (14,130 workers in total) who were occupationally exposed to inorganic lead. The blood and urine samples were analyzed for Pb-B and ALA-U by atomic absorption spectrometry and colorimetry, respectively, and the correlation between pairs of measures were subjected to statistical analysis. The assumption of the 3rd degree regression for correlation gave a substantially greater correlation coefficient (0.645 for men and 0.619 for women) than 1st or 2nd degree regression, whereas only very small improvement in the coefficient was achieved with 4th to 6th degree ones. Logarithmic conversion of the parameters was not effective in improving the correlation. The assumption of the 3rd degree regression followed by calculation of the local minimum gave 22, 29 and 23 micrograms/100 ml Pb-B for men, women, and men + women, respectively, as the threshold Pb-B to induce ALA-U increase. Pb-B to elevate ALA-U to the 95% upper normal limit (8 mg/l, common to men and women) was 62, 50 and 58 micrograms/100 ml for men, women and men + women, respectively. The validity of the 3rd degree regression assumption as a tool to calculate a threshold from experimental or epidemiological data is discussed.  相似文献   
86.
p53 mutation is commonly associated with high-grade, high-stage human urothelial carcinomas. Recent studies suggest that p53 mutation in low- grade, low-stage bladder carcinomas may be correlated with the progression of the disease. In the present study, we used antisense RNA methodology in vitro to evaluate the significance of the loss of p53 function at an early stage of urinary bladder carcinogenesis. An immortalized nontumorigenic rat urothelial cell line (MYP3) that strongly expresses wild-type (WT) p53 was transfected with a plasmid (pcDL-SR alpha-296) containing a rat WT p53 cDNA in antisense orientation. The transfection resulted in a significant reduction in p53 mRNA expression and protein synthesis, in stimulation of anchorage- dependent growth, and in acquisition of anchorage-independent growth potential. Three such clones, when tested in athymic nude mice, all formed muscle-invasive, high-grade transitional cell carcinomas at s.c. injection sites. When cells were inoculated into an orthotopic site (urinary bladder), one of two antisense transfectants tested formed bulky tumors in the bladder in all seven nude mice and metastases to lungs in three of the seven mice. Analysis of these cells revealed a decrease in the expression of p21 (WAF1, sdi1, or CIP1) and retinoblastoma (Rb) gene product. Phosphorylation of Rb protein was not inhibited when the cells were starved. No significant difference was observed in the expression of p16 protein. In cell cycle analysis, all antisense transfectants tested escaped from G1 arrest by starvation. Furthermore, secretion of interleukin (IL)-6 into culture medium was increased significantly. Treatment with anti-IL-6 antibody suppressed anchorage-dependent growth. This study directly demonstrates that the loss of p53 function at an early stage of urothelial carcinogenesis may result in acquisition of a malignant phenotype by regulating IL-6 production as well as cell cycle related genes.   相似文献   
87.
A 29-year-old woman was referred to our hospital for an abnormal shadow on chest roentgenogram. She had no symptom but its shadow was pointed out about 20 years ago. Chest CT scan showed a sharply demarcated homogenous mass measured 10 x 10 mm in the S4 segment. The tumor was resected with video-assisted thoracoscopic surgery under CT-guided marking wire inserted. Microscopic examination suspected cavernous hemangioma. Immunohistological staining demonstrated most lining cells of the cavernous structure stained positively for von Willebrand factor antibody, which suggests that this tumor was associated with endothelium. Then we decided that this tumor was pulmonary cavernous hemangioma.  相似文献   
88.
Intraosseous microcystic meningioma   总被引:2,自引:0,他引:2  
Extradural ectopic meningioma is a rare tumor. We report on an example of microcystic meningioma arising in the skull of an elderly woman. Radiological examination revealed a localized osteolytic lesion in the left parietal bone. At surgery, it was discovered that the tumor was located within the skull without any evidence of extraosseous extension. The light microscopic, immunohistochemical and ultrastructural features were consistent with a microcystic variant of meningioma. To our knowledge, this is the first case of an intraosseous microcystic meningioma, and we believe that this type of meningioma should be considered in the differential diagnoses of myxoid bone tumors of the calvarium. Received: 10 January 2000 Revision requested: 21 February 2000 Revision received: 8 March 2000 Accepted: 13 March 2000  相似文献   
89.
90.
A 39-year-old woman was hospitalized for nephrotic syndrome. Laboratory test results showed increased serum creatinine levels and urinary excretions of beta-2-microglobulin, and N-acetyl-beta-D-glucosaminidase. A renal biopsy revealed collapsing focal segmental glomerulosclerosis (FSGS) and acute interstitial nephritis. Despite treatment with pulse steroid followed by oral high-dose glucocorticoids and cyclosporines, heavy proteinuria persisted. After low-density lipoprotein apheresis (LDL-A) therapy was initiated, her proteinuria gradually decreased, leading to complete remission. A repeat renal biopsy after treatment revealed no collapsing glomeruli. Immediate LDL-A should be performed to treat cases of collapsing FSGS poorly responding to other treatments.  相似文献   
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