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52.

Purpose  

Glioblastoma multiforme (GBM) is characterized by tissue hypoxia associated with resistance to radiotherapy and chemotherapy. To clarify the biological link between hypoxia and tumour-induced neovascularization and tumour aggressiveness, we analysed detailed volumetric and spatial information of viable hypoxic tissue assessed by 18F-fluoromisonidazole (FMISO) PET relative to neovascularization in Gd-enhanced MRI and tumour aggressiveness by L-methyl-11C-methionine (MET) PET in newly diagnosed GBMs.  相似文献   
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BACKGROUND: The Japanese Red Cross (JRC) implemented a fully automated pooling and nucleic acid amplification test (NAT) system for testing seronegative donations. The JRC sample repository and repeat blood donations allowed for lookback and follow-up studies of hepatitis B virus (HBV) DNA-positive donors, who tested negative for hepatitis B surface antigen (HBsAg) and anti-hepatitis B core antigen in the JRC screening system. STUDY DESIGN AND METHODS: From February 1, 2000, to March 31, 2003, 17,314,486 units were tested in 50-sample pools with a semiautomated multiplex assay system (AMPLINAT MPX test, Roche). During this period, 328 HBV DNA-positive donations were found. From 26 of these donors, sequential samples were available at short intervals. This enabled us to examine the dynamics of viral markers in acute HBV infection. The length of detectable periods of plasma viremia and antigenemia were estimated by regression analysis from the results obtained in the quantitative polymerase chain reaction assay (JRC) and HBsAg enzyme immunoassay (Auszyme II, AxSYM, Abbott) and chemiluminescence immunoassay (Abbott). RESULTS: The median length of detectable HBV DNA in individual donation and 20-sample minipool (MP) NAT format was estimated to be 74 and 50 days, respectively, whereas the median length of detectable HBsAg was estimated to be 42 days. Six of the 26 donors were infected with mutant viruses, and 3 of these 6 donors did not develop detectable HBsAg during the entire observation period, despite a moderately high viral load of 10(4) to 10(5) HBV DNA copies per mL. CONCLUSION: Transmission of mutant virus may cause occult HBV infection in the acute stage. HBV NAT, even in MP configuration, is more effective than HBsAg testing and capable of interdicting infected donors in the pre- and post-HBsAg window periods.  相似文献   
54.
Adjuvant chemotherapy for non-small cell lung cancer   总被引:2,自引:0,他引:2  
Recently, several randomized trials with a large number of enrolled patients have shown that postoperative adjuvant treatment improves survival among patients with completely resected non-small cell lung cancer (NSCLC). Platinum-based chemotherapy has been reported to be effective for patients with postoperative stage I to IIIA NSCLC in western countries. On the other hand, uracil-tegafur was also shown to improve survival among patients with stage I adenocarcinoma in Japan. We reviewed the results of recent randomized trials and meta-analyses, and discuss the current role and problems related to adjuvant chemotherapy in NSCLC.  相似文献   
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An experimental study was conducted to determine whether pericardial fat tissue could induce neovascularization and produce cytokines related to tissue repair. Neovascularization was examined using chick chorioallantoic membranes. Pieces of pericardial fat tissue, omentum, and intercostal muscle were individually placed on a number of chorioallantoic membranes and neovascularization induced by each material was assayed 6 days after the implantation. The intensity of neovascularization was in the order of pericardial fat omentum > muscle. Cytokines, such as interleukin 1 (IL-1) and , tumor necrosis factor- (TNF), interferon- (IFN-), and interleukin 6 (IL-6) were assayed in a culture supernatant of pericardial fat tissue. The latter was obtained 24h after the addition of lipopolysaccharide (LPS) following various incubation times. All cytokines other than IFN are known to play a part in tissue repair, whereas IFN is negatively related to tissue repair because it inhibits fibroblast growth. The pericardial fat tissue incubated with LPS produced a certain amount of IL-1 on day 1, and TNF on days 1 and 8, whereafter these values decreased to an undetectable level. Irrespective of the addition of LPS, a large amount of IL-6 was observed in the supernatant of pericardial fat tissue and it was detectable until day 29. On the contrary, INF was not detected at any assay time. These observations suggest that a pericardial fat pad flap could possibly be beneficial in the prevention of bronchopleural fistula after pulmonary resection.  相似文献   
57.
To improve our understanding of the mechanisms underlying osteoporosis following renal transplantation, we compared bone mineral density (BMD) in 158 transplant recipients and in 293 patients undergoing maintenance hemodialysis with age- and sex- matched normal controls. Observations in graft recipients were made up to several years following transplantation. Dual-energy X-ray absorptiometry was used to measure BMD. Correlations with clinical variables including serum concentration of parathyroid hormone (PTH) and steroid therapy were evaluated. Lumbar BMD was lower in transplant patients than in dialysis patients at all ages, and continued to decrease with increasing interval posttransplant until the second year after transplantation. Persistent hyperparathyroidism and daily prednisolone dosage were both associated with decreased BMD. Age and creatinine clearance were independent long-term predictors of BMD by multiple regression analysis. Treatment of renal graft recipients with calcium and vitamin D supplements or calcitonin may be indicated in the early months after transplantation.  相似文献   
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BACKGROUND: The modified Rankin scale (mRS) is commonly employed as a measure of functional outcome after stroke. The purpose of this study was to investigate the reliability of the mRS using an expanded guidance scheme and a corresponding questionnaire on an unprecedentedly large scale. METHODS: Neurologists interviewed patients with cerebral infarction on the basis of the questionnaire. These interviews were recorded on videotape. Raters (10 neurologists, 6 nurses and 4 physiotherapists) watched the videotapes of 30 patients interviewed and assessed the mRS according to the guidance scheme. RESULTS: The agreement between the raters, as estimated from the intraclass correlation coefficient, was found to be satisfactory with values of 0.947 for neurologists and 0.963 for nurses and physiotherapists. The reproducibility was also satisfactory with values of 0.865 and 0.871, respectively. CONCLUSION: The data obtained suggest that our guidance scheme and questionnaire are useful for ensuring the quality of assessments made with the mRS.  相似文献   
60.
Mutations of the epidermal growth factor receptor (EGFR) gene play a critical role in carcinogenesis of lung cancer, particularly adenocarcinoma. However, to the best of our knowledge, no mutations of the EGFR in patients with lung carcinosarcoma have been identified. We herein report the case of a 61-year-old female referred for a detailed examination of a left pulmonary mass shadow. Although bronchoscopy was performed, it failed to lead to a diagnosis, and video-assisted thoracoscopic surgery was therefore carried out to diagnose the tumor. The pathology revealed biphasic features consisting of both adenocarcinoma and chondrosarcoma. Intriguingly, both the adenocarcinoma and chondrosarcoma components were proven to harbor an exon19 deletion in the EGFR gene. Although carcinosarcoma is a rare malignancy of the lungs, genetic analyses of oncogenic drivers, such as the EGFR gene, should be conducted.  相似文献   
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