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101.
PURPOSE: Strontium-89 chloride (89Sr) is a new radiopharmaceutical that provides effective pain relief for metastatic bone lesions, and is expected to be available soon in the palliative management for metastatic bone pain in Japan. Because of relatively long physical half life (50.5 days), 89Sr may affect to the radioactive draining-water system by exceeding the limits of activity concentration for radioactive drain. In this article, the influence of 89Sr use on the radioactive drainage system was simulated. METHODS: The standard tank capacity of drainage and draining frequency was determined from the results of questionnaire carried out for the nationwide medical and research institutes where radioisotope treatment are performed. On the assumption that 89Sr of 148 MBq for one therapy was used twice a week and several common radionuclides were used as the same activity as used at Chiba Cancer Center, the influence of 89Sr was estimated. The calculation was performed using the activity contamination ration into the draining-water system of each radionuclide of 0.01, which was legally determined. RESULTS: The simulation revealed that the sum of the contamination ratios of individual radionuclides exceeded a legal value of 1.0 in standard drainage with the capacity of 5 m3 and 10 m3 and draining frequency of 7 times per year. The actual contamination ratios of common radiopharmaceuticals measured at Chiba Cancer Center ranged from 1/100 to 1/1000 of the legal values. CONCLUSION: It is necessary that the legal value of activity contamination ratios into the draining-water system should be reassessed before starting 89Sr therapy.  相似文献   
102.
PURPOSE: The purpose of this research was to identify promiscuous T-helper cell determinants (THd) from carcinoembryonic antigen (CEA) to be used to prime T-cell help for cancer therapy. CEA was selected because this antigen is expressed in an important variety of carcinomas. EXPERIMENTAL DESIGN: Potential promiscuous THd from CEA were predicted using available computer algorithms. Predicted peptides were synthesized and tested in binding experiments to different HLA-DR molecules. Binder peptides were then used to prime T-cell responses both in vitro and in vivo. RESULTS: Twenty 15-mer peptides from CEA were predicted to bind to different HLA-DR molecules. The promiscuous character of these peptides was demonstrated in binding experiments. Fifteen of 20 peptides tested were able to bind to HLA-DR4, but only CEA (625-639) was shown to be presented after processing of recombinant CEA. CEA (625-639) was also found to be presented by HLA-DR53. Moreover, immunization of HLA-DR4 transgenic mice with CEA (625-639) in conjunction with class I epitope OVA (257-264), induced a CTL response specific of OVA (257-264). CONCLUSIONS: CEA (625-639) might be a relevant promiscuous THd peptide for cancer therapy.  相似文献   
103.
Desmoplastic fibroma is a relatively uncommon tumor and rarely involves the spine. The authors describe a 20-year-old woman with a thoracic epidural desmoplastic fibroma treated by complete resection and posterior spinal fusion. Four years after surgery, neither the tumor nor clinical symptoms have recurred. Thus, complete resection is considered necessary to treat this tumor.  相似文献   
104.
BACKGROUND: Uroguanylin, originally isolated from urine, is a new natriuretic peptide. Its plasma level is increased in association with renal impairment and fluid retention in patients with renal diseases. METHODS: Uroguanylin concentrations were measured in patients on hemodialysis (HD, n = 76) and those on continuous ambulatory peritoneal dialysis (CAPD, n = 10) using a sensitive ra- dioimmunoassay for human uroguanylin. RESULTS: Plasma concentrations of immunoreactive (ir)-uroguanylin in the patients on HD and CAPD (212.0 +/- 17.4 and 245.3 +/- 39.5 fmol/ml) were significantly higher than the value for the normal controls (5.0 +/- 0.3 fmol/ml). Plasma ir-uroguanylin levels before the start of regular HD were correlated with predialysis excess weight based on their dry weights (r = 0.33, p < 0.01) and with dialysis duration (r = 0.26, p < 0.05). The plasma levels in patients with HD, for whom high-flux membranes were used, were decreased at the end of regular HD as compared with the prior levels (p < 0.05), but not in those who underwent HD with conventional membranes. CONCLUSION: These findings suggest that the plasma ir-uroguanylin level is related to the patient's volume status as well as renal impairment. Whether the accumulation of uroguanylin has a pathological effect has yet to be determined.  相似文献   
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PURPOSE: To compare the accuracy of thin-section CT, conventional static MR imaging (conventional MRI), and breathing dynamic echo planar magnetic resonance imaging (BDEPI) in evaluating lung cancer invasion to the chest wall. MATERIALS AND METHODS: Thin-section CT, conventional MRI, and BDEPI were performed preoperatively in 20 patients suspected of having primary lung cancers adjacent to the chest wall on conventional CT. The results of imaging findings were compared with those of surgical and histopathological findings. RESULTS: All patients were confirmed to have no chest wall invasion after surgery. By thin-section CT, 10 of 20 patients were correctly diagnosed as having no chest wall invasion (50% specificity). Two of the 20 patients were incorrectly diagnosed as having chest wall invasion by conventional MRI and BDEPI (90% specificity). CONCLUSION: When chest wall invasion is suspected on CT scans, static and breathing dynamic MRI are recommended to avoid false positive interpretations.  相似文献   
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In an ultrasonically activated device, electric energy is transformed to mechanical vibration, which is transmitted to the device's tip. By clamping the vessel between the tissue pad and vibrating blade, frictional heat is generated. This heat, significantly milder than that in electrocautery technique, is ideal for sealing the vessel. The ultrasonic vibration eventually divides the vessel. In the experimental studies, the cut end of medium-sized vessels divided by a scissor type ultrasonically activated device (USAD) withstood high intravascular pressure. However, our clinical experiences with the USADs suggest there are pitfalls including:--giving excessive tension to the vessel,--incomplete clamping of the vessel,--contacting the adjacent vessel with the back side of the active blade tip,--contacting the adjacent vessel with the blade tip. Some devices are described to prevent these pitfalls.  相似文献   
110.
BACKGROUND: Percutaneous transhepatic portal vein embolization (PTPE) increases the safety of subsequent major hepatectomy. The aim of this study was to determine the effect of PTPE on long-term prognosis after hepatectomy in patients with hepatocellular carcinoma (HCC). METHODS: Seventy-one patients with HCC underwent right hepatectomy between 1984 and 1998. Preoperative PTPE was performed in 33 patients (group 1) and was not used in 38 patients (group 2). Outcome after operation was compared between the groups. The patients were further divided according to the median tumour diameter (cut-off 6 cm) and indocyanine green retention rate at 15 min (ICGR15) (cut-off 13 per cent). RESULTS: The cumulative survival rate was significantly higher in group 1 than in group 2 in patients with an ICGR15 of at least 13 per cent. Tumour-free survival rates were similar in both groups. Of patients with tumour recurrence after right hepatectomy, those in group 1 were more frequently subjected to further treatment. CONCLUSION: Preoperative PTPE improves the prognosis after right hepatectomy for HCC in patients with impaired hepatic function, although it does not prevent tumour recurrence.  相似文献   
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