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31.
BACKGROUND: Bacillus Calmette-Guerin (BCG) revaccination has been implemented in Japan among tuberculin-negative first grade primary and first grade junior high school students for decades. Controversies regarding the effectiveness of BCG revaccination and low incidence of tuberculosis (TB) among Japanese children prompted this study. METHODS: Cost-effectiveness and cost-benefit analyses were conducted for a cohort of schoolchildren who underwent revaccination during 1996. The study population was a hypothetical cohort comprising 1.35 million first grade primary school and 1.51 million first grade junior high school students enrolled in 1996 at locations throughout Japan. Assuming 50% vaccine efficacy for revaccination, a 10-year duration of protection, and 5% annual discount rate, we calculated the total hypothetical number of TB cases averted, the cost and number of immunizations per TB case averted, and the benefit-cost ratio for the program. RESULTS: The revaccination program for 1996 schoolchildren cohort would prevent 296 TB cases over a 10-year period at a cost of US$ 108,378 per case averted. About 4,963 immunizations would be required to prevent one child from developing TB. The benefit-cost ratio remained at 0.13 with baseline assumptions and ranged from 0.05 to 0.29 and from 0.02 to 0.74 for one-way and two-way sensitivity analyses, respectively. CONCLUSION: BCG revaccination among schoolchildren is not supported by available scientific and economic data. Based on the results of this study, current BCG revaccination policies in Japan and other countries should be reexamined.  相似文献   
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BACKGROUND: Macrophage migration inhibitory factor (MIF) is a pivotal cytokine that regulates inflammatory and immune responses. Recently, many investigators reported that MIF is expressed highly in several tumors, including hepatocellular carcinoma (HCC). However, the role of MIF in tumor angiogenesis and patient prognosis has not been examined in patients with HCC. METHODS: The authors evaluated MIF expression in 56 samples of HCC by Western blot analysis, and the results were correlated with clinicopathologic factors and patient prognosis. MIF localization was determined by immunohistochemical methods, and the results were compared with tumor microvessel density (MVD), as assessed by anti-CD34 antibody. Furthermore, to validate the role of MIF in angiogenesis, both MIF expression during culture of HCC cells (using the Hep3B, HepG2, and Huh7 cell lines) under hypoxic condition and the angiogenic potential of recombinant MIF in an in vitro angiogenic model were examined. RESULTS: Tumors with high MIF expression had high alpha-fetoprotein levels (P = 0.049) and frequent intrahepatic recurrence (P = 0.043). Immunohistochemical MIF scores had a significant correlation with MVD (P = 0.007). Patients who had tumors with high MIF expression levels had a significantly worse (P = 0.025) disease-free survival, and this finding remained significant as an independent prognostic factor in the multivariate analysis. Hep3B cells had high expression of MIF at 6 hours and 12 hours after hypoxic stress and exogenous MIF stimulated endothelial tube formation in in vitro angiogenesis. CONCLUSIONS: The current findings suggest that MIF expression may play a pivotal role in the dismal prognosis of patients with HCC that may be attributable to the modulation of angiogenesis.  相似文献   
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BACKGROUND: The effect of ionizing radiation on extracellular matrix (ECM)-mediated cellular functions is an important area of research for translational science. Mechanisms of tumor cell ability to proliferate, migrate, and survive appear dependent on integrin-mediated adhesion to the ECM; however, the exact role therapeutic radiation plays in altering signaling pathways and promoting cell death within remains less well established. METHODS: To examine these effects on prostate carcinoma cell lines, cells were irradiated at sub-lethal doses. We have studied two human prostate cancer cell lines (PC3 and DU-145) irradiated with different fractionated radiation schedules. Three groups were compared to non-irradiated controls. Group A was given a single dose of 5 Gy. Group B was given 5 Gy the first week and then 10 Gy the second week for a total of 15 Gy. Group C was given 5 Gy the first week, and then 10 Gy the second and third week for a total of 25 Gy. Cells were analyzed at their prescribed total dose. At 48 hr post irradiation, cells were detached from culture dishes and were subsequently used for adhesion assays and immunoblotting analysis. RESULTS: Our findings revealed that two prostate carcinoma cell lines, PC3 and DU-145, had a reduced cellular adhesion to fibronectin (FN) compared to the non-irradiated control groups. Both prostate cancer cell lines showed decreased adhesion to FN and reduced beta(1) integrin protein levels at a total dose of 25 Gy, but not at the doses of 15 and 5 Gy. In a parallel analysis, at the maximum total dose of 25 Gy, both PC3 and DU-145 demonstrated a significant decrease in cell proliferation. CONCLUSIONS: High dose radiation treatment of prostate cancer cell lines inhibits integrin expression. Our study suggests that promoting a synergistic decrease in adhesion could bring additional therapeutic benefit to patients treated with radiation therapy.  相似文献   
35.
We established a pilot telemedicine network for paediatric oncology in Brazil, linking the School of Medicine at the University of Sao Paulo in Sao Paulo City to the 'Hospital de Base' in Porto Velho, Rondonia, located in the Amazon region, 3,000 km away. The videoconferencing link used ISDN transmission at 384 kbit/s. The network was used for patient screening, follow-up, treatment monitoring and other activities. Between March 2000 and 2002, 69 videoconferences were held for 33 patients, 29 with cancer. During this period, 16 patients required transfer, 18 patients died and 11 achieved cancer remission. The main cause for patient mortality (infection) was not one that could be addressed directly by telemedicine. Using the School of Medicine as a benchmark, the average mortality rate for paediatric cancer patients in the pilot was higher. However, it was lower than previous levels observed at Rondonia (62% versus 80%).  相似文献   
36.
We have established a Web-based system in Brazil offering health information in childhood cancer and services such as electronic patient records and treatment protocols. The system was based on open-source software. The database has records for about 3,200 patients from 30 Brazilian hospitals. An evaluation by doctors from the six hospitals comprising the Neuroblastoma Cooperative Group was positive, mainly because the system allows easy online access, but also because the electronic register performs data validation when information is inserted. Our experience shows that it is possible to use a Web-based system to provide paediatric cancer services at a distance.  相似文献   
37.
AIM: Prevalences of overweight in The Netherlands, defined by international cut-off points, are presented in 14 500 children of Dutch origin, 2904 of Turkish and 2855 of Moroccan origin, aged 0-21 y. RESULTS: The mean prevalence for Turkish boys and girls was 23.4% and 30.2%, for Moroccans 15.8% and 24.5%, for Dutch youths in large cities 12.6% and 16.5%, and for other Dutch participants 8.7% and 11.3%, respectively. CONCLUSION: The development of adequate prevention strategies is urgently needed.  相似文献   
38.
A 35-year-old women presented with breathlessness and features suggestive of pulmonary hypertension. Further investigations revealed that she had autoimmune hepatitis and both portal and pulmonary hypertension. Pertinent literature is reviewed.  相似文献   
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Skeletal echinococcosis is a relatively rare entity and that of the rib is exceptional. Less than 50 cases of costal echinococcosis have been reported in the literature so far. Accurate pre-operative diagnosis aids in appropriate management and helps to eradicate the disease. This also prevents the dissemination of parasite and further complications. We report a case of echinococcosis of the rib with epidural extension in a young adult who presented with paraparesis and back pain. His laboratory investigations were within normal limits. Plain radiographs of the dorsal spine, CT scan of thorax and MRI of dorsal spine were performed. The imaging features were suggestive of echinococcosis involving the rib with epidural extension. The cyst was completely resected. Histopathology of the resected specimen confirmed the diagnosis of echinococcosis.  相似文献   
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