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551.
OBJECTIVES: To investigate the feasibility and safety of the percutaneous dilatation of coronary septal collaterals and to allow its use as an access for retrograde approach to percutaneous coronary intervention (PCI) of coronary chronic total occlusions (CTOs). BACKGROUND: Despite improvements in percutaneous techniques and materials, CTO recanalization success rate is still suboptimal. The retrograde approach allows to significantly increase this success rate. However, its application via a bypass graft or epicardial collateral can potentially result in severe complications. A safer retrograde access is desired and would allow broadening the application of the retrograde approach in the percutaneous treatment of CTOs. METHODS: After a failed antegrade CTO recanalization attempt, a retrograde approach via septal collaterals was tried in 21 patients (19 males, 2 females). The septal collateral was accessed via the contralateral patent coronary artery and was crossed with a hydrophilic floppy wire. After successful wire crossing of the septal collateral, sequential low pressure dilatation was performed with a 1.25 or 1.5 mm balloon to allow the delivery of a balloon catheter up to the distal CTO site. RESULTS: Successful wire crossing and balloon dilatation of septal collaterals was achieved in 19 cases and in 17 cases, respectively. Postdilatation septal collateral diameter increased significantly reaching a mean diameter of 1.46 +/- 0.38 mm. Retrograde CTO recanalization was successfully performed in 71% of the cases. No major complications occurred. CONCLUSIONS: Coronary septal collaterals can be used as an access for the retrograde approach in the percutaneous treatment of CTOs.  相似文献   
552.
To determine the clinical and tumor stage of hepatocellular carcinoma (HCC) that is the best indication for surgery, the postoperative long-term outcomes of patients who underwent hepatic resection were examined retrospectively. Of 975 patients with HCC who underwent regional therapy, 384 patients (39%) received hepatic resection (HR), 534 (55%) had transcatheter arterial chemoembolization (TACE), and the remaining 57 (6%) received percutaneous ethanol injection (PEI) into the tumor. The criteria defined by liver Cancer Study Group of Japan was used for staging and liver functional reserve (i.e., clinical staging).1 In the 133 patients with stage I HCC, there were no significant differences among the survivals of the HR, TACE, and PEI groups. In the 314 patients with stage II HCC, the 5- and 7-year survival rates were 51% and 46% in the HR group, 23% and 10% in the TACE group, and 0% and 0% in the PEI group. The survival of the HR group was significantly better than the survivals of the TACE and PEI groups (P < 0.001). The 5- and 10-year survivals of the stage II HCC patients who had HR were 64% and 47% in the clinical stage I (i.e., good liver function) group, significantly better than the 5; and 10-year survivals (32% and 23%) in the clinical stage II (i.e., bad liver function) group (P < 0.0001). Patients with good liver function in stage II are expected to have better survival and are considered to be the most suitable for HR.  相似文献   
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The purpose of this retrospective study was to compare the toxicity and disease control rate of radiotherapy for prostate cancer in salvage settings after high-intensity focused ultrasound (HIFU) therapy (HIFU cohort) with those in radical settings (non-HIFU cohort). From 2012 to 2020, 215 patients were identified for this study and 17 were treated in the salvage settings after HIFU. The median follow-up time was 34.5 months (range: 7–102 months, inter-quartile range [IQR]: 16–64 months). Genitourinary (GU) and gastrointestinal (GI) adverse events were evaluated in acute and late periods with Common Terminology Criteria for Adverse Events version 5, and the rates of biochemical-clinical failure free survival (BCFS) and overall survival (OS) were estimated. The cumulative incidence of late GU Grade 2 or greater toxicity after five years was significantly different between the non-HIFU and HIFU cohorts with rates of 7.3% and 26.2%, respectively (P = 0.03). Regarding GI Grade 2 or greater toxicity, there was no significant difference between the two cohorts. The 5y-BCFS was 84.2% in the non-HIFU cohort and 69.5% in the HIFU cohort with no significant difference (P = 0.10) and the 5y-OS was 95.9% and 92.3%, respectively (P = 0.47). We concluded that the possibility of increased late GU Grade 2 or greater should be considered when applying salvage radiotherapy for local recurrence after HIFU.  相似文献   
556.
To investigate molecular responses to lipid peroxidative stimuli in neoplastic cells, lipid peroxidation was induced in liver of rats bearing 3'-methyl-4-dimethylaminoazobenzene-induced hepatocellular carcinoma by injecting a high dose of carbon tetrachloride (CCL4), a strong lipoperoxidative reagent. Normal rat livers with or without CCl4 treatment served as controls. CCL4, administration markedly provoked fatty metamorphosis, visualized by oil red O staining, in normal livers while minimal fatty changes were seen in hepatocellular carcinomas, where necrosis was often observed instead. After CCl4 treatment, the thiobarbituric acid values (representing levels of lipid peroxides in the tissue) were increased two–fold in the untreated normal liver, but were unchanged in the cancer tissue. Levels of vitamin C, an acutely reactive antioxidant, measured by high-performance liquid chromatography were not influenced by the CCL4 injection in the cancer tissue whereas a significant decrease was evident in normal livers. The total fatty acid content, measured by gas chromatography, was significantly lower in the cancer tissue than in the normal liver while the ratio of polyunsaturated fatty acids (PUFAs) in total fatty acids was little changed. Resistance of hepatocellular cancer cells to fatty metamorphosis and their susceptibility to necrosis induced by free radicals may be due to the paucity of the target PUFAs in their cell membrane fraction, resulting in low levels of lipid peroxides. Peroxidation of PUFAs might act as a "shock absorber" against free radical-induced toxic cell death in normal cells.  相似文献   
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