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61.
The modifying effects of quinacrine administration during the post-initiation phase of carcinogenesis were investigated in hamsters treated with N -nitrosobis(2-oxopropyl)amine (BOP). Female Syrian hamsters were given three weekly s.c. injections of BOP at a dose of 10 mg/kg and then 300 or 100 ppm quinacrine in their diet for 37 weeks. Additional groups of animals received the BOP injection alone, or only the 300 ppm quinacrine treatment as BOP-negative controls. At week 40 of the experiment, all surviving animals were killed and development of proliferative lesions was assessed histopathologically. The multiplicity of pancreatic adenocarcinomas and dysplastic lesions per hamster was significantly higher ( P <0.01 and P <0.05) in the BOP/Q100 group (1.92 and 1.78) than in the BOP-alone group (1.07 and 0.79). The incidence of hepatocellular adenomas plus carcinomas was also significantly elevated ( P <0.05) in the BOP/Q300 and BOP/Q100 groups. In contrast, the multiplicity of lung adenomas plus adenocarcinomas was significantly decreased ( P <0.05) by the Q300 treatment. Neither the incidence nor the multiplicity of renal cell tumors (adenomas and carcinomas) or nephroblastomas significantly differed between the BOP-treated groups. Electron microscopic examination revealed an abundance of myeloid lamellar bodies filling the cytoplasm of hepatocytes and pancreatic ductular and acinar cells, and epithelial cells of the gallbladder in the quinacrine-treated animals, the degree being dose-dependent. Our results indicate that quinacrine enhances pancreatic and hepatic carcinogenesis in hamsters induced by BOP.  相似文献   
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We report a rare case of anterior mediastinal thymic cyst together with a thymoma and its intracystic dissemination. More attention should be given to intramural nodules, especially in patients with an anterior mediastinal thin wall cystic lesion.  相似文献   
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We have reported that excess soybean treatment and iodine deficiency synergistically interact, resulting in remarkable induction of thyroid hyperplasias in rats. In the present study, modifying effects of excess soybean and iodine-deficient diets were investigated in the post-initiation phase of N-bis(2-hydroxypropyl)nitrosamine [DHPN]-initiated thyroid tumorigenesis in rats. AIN-93G in which casein was replaced with gluten was used as a basal diet to avoid possible iodine contamination. In Experiment 1, F-344 rats of both sexes were sc injected with DHPN at a dose of 2800 mg/kg body weight and then fed a diet containing 0%, 0.8%, 4%, or 20% defatted soybean for 12 weeks, with proportional replacement of gluten by soybean flour. Although no thyroid proliferative lesions were found in any group, the absolute thyroid weights were significantly (p < 0.01) elevated with the 20% soybean treatment. In Experiment 2, after similar sc injection of DHPN, rats were fed a basal diet or a diet containing 20% soybean under iodine normal or deficient conditions for 12 weeks. Soybean feeding to both sexes under iodine deficient but not normal conditions dramatically enhanced the development of thyroid follicular adenomas (p < 0.01) and adenocarcinomas (p < 0.05), in good agreement with decrease in thyroxine and increase in thyroid-stimulating hormone. Thus co-exposure to excess soybean and iodine deficiency results in synergistic promotion of DHPN-initiated thyroid tumorigenesis in rats, of which mechanisms appear to primarily involve effects on serum hormone levels.  相似文献   
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Purpose: We investigated the influence of intraoperative continuous tranexamic acid (TA) infusion on the amount of blood transfusion required in emergency surgery for type A acute aortic dissection.Methods: The study was based on the data of 55 consecutive patients who underwent surgery for type A acute aortic dissection. The patients were divided into 2 groups for comparison: Group T, consisting of 26 patients who received intraoperative continuous infusion of TA, and Group N, consisting of 29 patients who did not receive TA infusion during the surgery.Results: The mean amounts of blood transfusion required during and after surgery were compared between the 2 groups: they were 10.5 ± 8.7 and 16.2 ± 10.0 units of mannitol-adenine-phosphate-added red cell concentrate, 9.3 ± 8.6 and 17.1 ± 10.0 units of fresh frozen plasma, and 20.4 ± 12.2 and 29.7 ± 14.9 units of platelet concentrate, respectively, in Groups T and N. Thus, the amount of each of these blood products required was significantly reduced in Group T.Conclusions: During emergency surgery for type A acute aortic dissection, continuous infusion of TA resulted in a significant reduction in the amount of blood transfusion required.  相似文献   
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BackgroundLocomotive syndrome (LS) was proposed by the Japanese Orthopedic Association and refers to a scenario in which imminent future nursing care services will be required by elderly adults to manage the functional deterioration of their locomotive organs. It is a social imperative to clarify the risk factors and treatment strategy for LS. However, the relationship between LS and adult spinal deformity (ASD) in those who are treated with spinal corrective surgery remains largely unknown.MethodsForty consecutive patients who had ASD and underwent spinal surgery for their disorder were included in this study. Locomotive dysfunction was evaluated using the 25-item Geriatric Locomotive Function Scale-25 (GLFS-25) questionnaire and physical performance tests including the one-legged standing test, the two-step test, the stand-up test, the handgrip strength, and gait speed test which were measured preoperatively, 6 months after surgery, and 1 year after surgery.ResultsOf the patients with ASD treated surgically, 95% of them had LS preoperatively and LS prevalence decreased significantly 1 year after surgery by 67.5% compared with the preoperative rate. Among physical performance tests, the walking stride and one-legged standing test improved significantly after spinal corrective surgery. The GLFS-25 items for the domains of pain, mobility, and domestic life improved overall postoperatively, whereas items in the self-care domain did not and the item for difficulty in putting on and taking off trousers and pants worsened.ConclusionsSpinal corrective surgery significantly improved physical performance tests as well as the frequency and severity of LS in patients with ASD. However, some GLFS-25 items can worsen after surgery and require attention.  相似文献   
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