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Objectives To develop a simple image viewer that utilizes image files in general-purpose formats that are written from the original 3DX volume data. Methods We used FLASH MX2004 for Macintosh to develop a simple image viewer. In developing the software for the simple image viewer, we decided that the viewer should provide the following features: (1) be available to both Windows OS and Mac OS, (2) allow interlocking of the 3D images, (3) display image enlargement, and (4) allow distance measurements. The accuracy of the distance measurements was evaluated. Results The procedure was as follows: (1) write 3D images in jpeg format to a folder on i-VIEW; (2) place the folder containing the 3D images into the directory of the simple image viewer software on a PC; (3) start the software and open the window to input the folder name containing the 3D images; and (4) display the 3D images. Our viewer had features such as image enlargement, interlocking 3D images, drawing, and distance measurements. No significant differences were shown between the measurements made by our simple viewer and the actual values of the images in any direction. Conclusions Our image-viewing software for 3DX is beneficial for clinical use.  相似文献   
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To clarify the genetic aberrations involved in the development and progression of hepatitis C virus-associated hepatocellular carcinoma (HCV-HCC), we investigated DNA copy number aberrations (DCNAs) in 19 surgically resected HCCs by conventional CGH and array CGH. Conventional CGH revealed that increases of DNA copy number were frequent at 1q (79% of the cases), 8q (37%), 6p (32%), and 10p (32%) and that decreases were frequent at 17p (79%), 16q (58%), 4q (53%), 13q (42%), 10q (37%), 1p (32%), and 8p (32%). In general, genes that showed DCNAs by array CGH were usually located in chromosomal regions with DCNAs detected by conventional CGH analysis. Increases in copy numbers of the LAMC2, TGFB2, and AKT3 genes (located on 1q) and decreases in copy numbers of FGR/SRC2 and CYLD (located on 1p and 16q, respectively) were observed in more than 30% of tumors, including small, well-differentiated carcinomas. These findings suggest that these genes are associated with the development of HCV-HCC. Increases of MOS, MYC, EXT1, and PTK2 (located on 8q) were detected exclusively in moderately and poorly differentiated tumors, suggesting that these alterations contribute to tumor progression. In conclusion, chromosomal and array CGH technologies allow identification of genes involved in the development and progression of HCV-HCC.  相似文献   
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Promoting effects of Na or K phosphate salts on rat two-stage bladder carcinogenesis were compared. Animals were treated with 0.05% N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) in their drinking water for 4 weeks and thereafter received 1.4% Na3PO4, 2.0% NaH2PO4, 1.0% K3PO4, or 2.5% KH2PO4, these dietary concentrations being selected because they result in approximately equal levels of Na+ and K+ in the urine, equivalent to moderate natriuresis or kaluresis in comparison with our previous data. Treatment with Na3PO4 or K3PO4 induced significant increase in urinary pH compared with control values, whereas urinary pH in the NaH2PO4 and KH2PO4 groups was comparable to control values. With regard to preneoplastic lesion development, both incidences and multiplicity were significantly increased in the groups given Na3PO4 or K3PO4 compared with both controls and NaH2PO4 or KH2PO4 groups, respectively. Furthermore, treatment with Na3PO4 significantly increased multiplicity of papillomas, accompanied by a tendency to increased incidence. No statistically significant difference in promoting potential between Na3PO4 and K3PO4 groups was evident. The present results thus suggest that tumor promotion under conditions of moderate natriuresis or kaluresis depends primarily on high urinary pH.  相似文献   
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Three-dimensional fast asymmetric spin echo (3D FASE) cisternography provides high spatial resolution and excellent contrast as a water image acquisition technique. It is also useful for the evaluation of various anatomical regions. This study investigated the usefulness and limitations of virtual endoscopic images obtained by 3D FASE MR cisternography in the preoperative evaluation of patients with neurovascular compression. The study included 12 patients with neurovascular compression: 10 with hemifacial spasm and two with trigeminal neuralgia. The diagnosis was surgically confirmed in all patients. The virtual endoscopic images obtained were judged to be of acceptable quality for interpretation in all cases. The areas of compression identified in preoperative diagnosis with virtual endoscopic images showed good agreement with those observed from surgery, except in one case in which the common trunk of the anterior inferior cerebellar artery and posterior inferior cerebellar artery (AICA-PICA) bifurcated near the root exit zone of the facial nerve. The veins are displayed in some cases but not in others. The main advantage of generating virtual endoscopic images is that such images can be used for surgical simulation, allowing the neurosurgeon to perform surgical procedures with greater confidence.  相似文献   
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The clinical effects and problems of intra-arterial water-soluble antitumor nitrosourea (ACNU) therapy following osmotic blood-brain barrier modification are discussed. Twenty-one patients with malignant brain tumors were divided into two groups. Group 1 consisted of 16 patients treated by operation, irradiation, and two or more courses of intracarotid infusion of ACNU 100 mg/body (1.7-2.2 mg/kg) following 20% mannitol 200 ml (1.3-1.6 ml/sec) (7 grade 4 astrocytomas, 5 grade 3 astrocytomas, and 4 others). Group 2 consisted of five patients treated by operation, irradiation, and repeated intracarotid infusion of ACNU 100 mg/body alone (grade 4 astrocytoma). The 2-year survival rate in Group 1 was 79% (11 of 14 cases followed up for longer than 2 years) and the 3-year survival rate was 67%. Five of seven grade 4 astrocytoma patients (71%) in Group 1 survived for more than 1 year 6 months, whereas four of five grade 4 astrocytoma in Group 2 died within 1 year 6 months. The measurement of the ACNU concentration in tumor tissues and blood in 11 brain tumors, after intracarotid infusion of ACNU with blood-brain barrier disruption, showed peak values in the tumor tissues of 3.02-32.53 micrograms/gm (mean, 9.67 micrograms/gm), about three to five times as high as that in blood in most cases. This method used in Group 1 appears to be relatively safe without permanent neurological deficits and offers a potential therapeutic effect when used in combination with appropriate premedication in suitable patients.  相似文献   
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Selective and superselective infusion of urokinase for embolic stroke.   总被引:6,自引:0,他引:6  
Intraarterial administration of urokinase using Tracker microcatheter was performed in 11 patients with acute cerebral infarction caused by embolic occlusion of the internal carotid or the middle cerebral artery. Recanalization was observed in seven cases (64%) following the fibrinolytic therapy, and the time until recanalization from the start of the treatment was on the average 2.8 hours. Recanalization was seen in five out of six cases that received superselective infusion of urokinase, while it was seen in two out of five cases that received selective infusion. This study suggests that superselective infusion of urokinase is an excellent therapeutic method for embolic occlusion of the cerebral artery.  相似文献   
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