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651.
This article discusses methodological issues confronting health professionals using questionnaires to study health care variables among populations with limited literacy in English, and suggests techniques for minimizing problems that plague questionnaire-based research among these populations. A recent effort to validate a questionnaire for Rheumatoid Arthritis patients in South Texas is used to illustrate pitfalls and potential solutions.  相似文献   
652.
Benzo[a]pyrene (BP) was bound to DNA by horseradish peroxidase, rat liver microsomes, and rat liver nuclei in vitro and in mouse skin in vivo. The BP-DNA adducts formed were analyzed by the 32P-postlabeling technique. Activation by microsomes and nuclei resulted in the detection of five adducts, including a major adduct (55%) which cochromatographed with the adduct (+/-)-10 beta-deoxyguanosin-N2-yl-7 beta, 8 alpha, 9 alpha-trihydroxy-7,8,9,10-tetrahydro-BP (BPDE-N2dG) formed by reaction of (+/-)-7 beta, 8 alpha-dihydroxy-9 alpha, 10 alpha-epoxy-7,8,9,10-tetrahydro-BP (BPDE) with DNA or by microsomal activation of BP 7,8-dihydrodiol. Activation by horseradish peroxidase, which catalyzes one-electron oxidation, produced seven adducts, including a major one (30%) that coeluted with an adduct observed with microsomal (2%) and nuclear (14%) activation. The pattern of adducts formed in mouse skin treated with BP in vivo for 4 or 24 h contained four of the same adducts observed with nuclei or microsomes in vitro, and the predominant adduct detected (86%) was BPDE-N2dG. The adduct common to horseradish peroxidase, microsomes, and nuclei was also detected in mouse skin DNA (2%). These results demonstrate that multiple BP-DNA adducts are formed in these in vitro and in vivo systems and suggest that at least one adduct is formed in common in all of the systems. Thus, it appears that stable BP adducts can be formed in mouse skin DNA by both monooxygenation and one-electron oxidation.  相似文献   
653.
Orbital tuberculoma masquerading as an orbital malignancy   总被引:1,自引:0,他引:1  
Background: Orbital tuberculosis is exceedingly rare in areas where tuberculosis is non-endemic. A case of childhood orbital tuberculosis is reported, which the authors believe to be the first reported case of orbital tuberculosis in the Australasian region. Methods/Results: The patient, a 6-year-old boy, presented with proptosis and was initially mistaken to have an orbital malignancy. Treatment with antituberculous drugs resulted in resolution of the condition. Conclusion: This case served as a timely reminder of the need to keep awareness of the extrapulmonary manifestations of tuberculosis alive even in developed countries. A high index of suspicion for this eminently treatable disease in the appropriate clinical situation is particularly important when migrant communities from high-prevalence areas are involved.  相似文献   
654.
Benzo[a]pyrene (BP) and cyclopenteno[cd]pyrene (CPEP) are widespreadenvironmental pollutants. CPEP is a relatively potent carcinogenin mouse skin with an activity second only to BP among environmentalaromatic hydrocarbons. We have studied the combined applicationof BP and CPEP on mouse skin to determine their possible synergisticcarcinogenic effect. Nine-week-old female Swiss mice in groupsof 30 were treated on the back with high (H), medium (M) andlow (L) doses, respectively, of 20 (H), 6.6 (M) or 2.2 (L) nmolBP or 200 (H), 66.6 (M) or 22.2 (L) nmol CPEP in 50 µlacetone twice weekly for 48 weeks. Other groups received BP-H+ CPEP-H, BP-M + CPEP-M, BP-L + CPEP-L, BP-H + CPEP-L, BP-M+ CPEP-L, BP-L + CPEP-H, or BP-L + CPEP-M. A significant, 3-to 7-fold syncarcinogenic effect occurred when BP-M + CPEP-Mwere administered together. A smaller, but significant, synergisticeffect (1.2- to 3.8-fold) was also observed when BP-M + CPEP-Lor BP-L + CPEP-M was applied. Because of the syncarcinogeniceffect of BP and CPEP, their abundance in engine emissions andambient air samples may present a major source of carcinogenicrisk.  相似文献   
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657.
Posttransplantation lymphoproliferative disorders (PTLD) is not uncommon and can occur in 2% to 5% of solid organ recipients on immunosuppression. Epstein-Barr virus (EBV) infection or reactivation and intensive anti-T lymphocyte treatment are important pathogenetic factors for a large proportion of these disorders. Nonclonal lesions with polymorphous histology have a potential for regressing when the immunosuppressants are reduced or stopped. Clonal tumors with a monomorphous histology carry a poor prognosis, and the mortality rate for monoclonal lymphoma has been reported as high as 80%. We report a renal transplant recipient who developed high-grade monoclonal lymphoma only 4 months after a live-donor transplantation. The tumor was EBV positive. Reduction of immunosuppressants resulted in minimal regression of the tumor. The patient was treated with adoptive immunotherapy using ex vivo generation of autologous lymphocyte activated killer (LAK) cells. She had leukapheresis, and autologous peripheral blood mononuclear cells were obtained and cultured in interleukin-2 (IL-2)-rich medium for 9 to 10 days. The IL-2-activated LAK cells were reinfused into the patient without any systemic administration of IL-2. The patient experienced no side effects during the infusion. There was no rejection episode, and the renal function of the patient remained stable after treatment. Computed tomography scan performed 2 months after the infusion showed marked regression of the lesions in the liver and spleen. Five months later, magnetic resonance imaging showed complete resolution of the tumor lesions. Ultrasonography 13 months after the LAK cell infusion showed no lesion. The allograft function was not affected after treatment. Adoptive immunotherapy using IL-2-activated autologous LAK cells was effective in treating this renal transplant patient with EBV-positive high-grade lymphoma. The patient's kidney allograft functioned well without any rejection.  相似文献   
658.
A rapid dot enzyme-linked immunosorbent assay (dot-ELISA) was developed as a field test for the diagnosis of cystic hydatid disease caused by Echinococcus granulosus. The 30 min test was based on the detection of antibodies to antigen B of hydatid fluid and was carried out using 50 microliters of whole blood in a field assessment in the Turkana region of north-west Kenya. Initial laboratory studies showed antigen B to be preferable to crude cyst fluid, with 94% sensitivity and 90.3% specificity for Echinococcus infections. The field test was rapid, inexpensive and simple to perform and is considered to be a useful back-up to ultrasound scanning.  相似文献   
659.
Total or partial deficiency of factor VIII and IX in the coagulation cascade leads to haemophilia. Haemophilia affecting weight-bearing joints gives a‘pseudotumour’or haemarthrosis-like condition. Surgery and cryoprecipitate infusions have been the treatment for this condition. Radiocolloids and radiation therapy have been used with some benefit. One case of ankle pseudotumour which was treated by low-dose external beam radiation is presented here.  相似文献   
660.
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