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71.
The United Kingdom Childhood Cancer Study, a population-based case-control study covering the whole of Great Britain, incorporated a pilot study measuring electric fields. Measurements were made in the homes of 473 children who were diagnosed with a malignant neoplasm between 1992 and 1996 and who were aged 0-14 at diagnosis, together with 453 controls matched on age, sex and geographical location. Exposure assessments comprised resultant spot measurements in the child's bedroom and the family living-room. Temporal stability of bedroom fields was investigated through continuous logging of the 48-h vertical component at the child's bedside supported by repeat spot measurements. The principal exposure metric used was the mean of the pillow and bed centre measurements. For the 273 cases and 276 controls with fully validated measures, comparing those with a measured electric field exposure >/=20 V m(-1) to those in a reference category of exposure <10 V m(-1), odds ratios of 1.31 (95% confidence interval 0.68-2.54) for acute lymphoblastic leukaemia, 1.32 (95% confidence interval 0.73-2.39) for total leukaemia, 2.12 (95% confidence interval 0.78-5.78) for central nervous system cancers and 1.26 (95% confidence interval 0.77-2.07) for all malignancies were obtained. When considering the 426 cases and 419 controls with no invalid measures, the corresponding odds ratios were 0.86 (95% confidence interval 0.49-1.51) for acute lymphoblastic leukaemia, 0.93 (95% confidence interval 0.56-1.54) for total leukaemia, 1.43 (95% confidence interval 0.68-3.02) for central nervous system cancers and 0.90 (95% confidence interval 0.59-1.35) for all malignancies. With exposure modelled as a continuous variable, odds ratios for an increase in the principal metric of 10 V m(-1) were close to unity for all disease categories, never differing significantly from one.  相似文献   
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ObjectiveVaccination with the first licensed dengue vaccine is recommended only for those who have had previous infection with dengue virus (DENV). A point-of-care test with the desired sensitivity of 95% and specificity of 98% could facilitate pre-vaccination screening. We evaluated a newly developed, automated dengue immunoglobulin fluorescence immunoassay for determining dengue serostatus.MethodsWe used serum samples collected just prior to a mass dengue vaccination in Cebu, Philippines. Healthy children residing in Bogo and Balamban who would be 9–14 years old at the time of the mass dengue vaccination were eligible to participate. We evaluated the ichroma? II dengue fluorescence immunoassay (Boditech Med Incorporated, Gang-won-do, Republic of Korea) using a neutralization test (NT) as the reference assay.ResultsWe enrolled 2996 children (mean age 10.39 years, 51.7% female) in the cohort and included a subsample of 1000 (mean age 10.56 years, 54.4% female) in this study. Of the 1000 children, 86/1000 (8.6%) tested seronegative and 914/1000 (91.4%) seropositive for DENV antibodies by neutralization testing. Compared with the NT, the dengue IgG fluorescence immunoassay had an overall specificity of 90.7% (95%CI: 82.5–95.9%) and a sensitivity of 91.8% (95%CI: 89.8–93.5%) for determining dengue seropositivity. The sensitivity declined to 51.2% (42.3–61.0%) for the detection of the subset with a monotypic dengue profile.ConclusionThe insufficient specificity and sensitivity (particularly in the detection of a previous monotypic dengue infection) would render the test, in its current state, inadequate for pre-vaccination screening. Considering its user-friendly interphase and possibility of point-of-care use, the test could be further developed and validated to improve its performance characteristics.  相似文献   
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BACKGROUND: Topical thrombin spray is frequently used as a hemostatic agent in surgery, particularly following cardiovascular, orthopedic and neurologic surgery. Acquired coagulation factor inhibitors to thrombin and factor V may develop following gynecologic surgery with repeat topical thrombin use. CASE: A 45-year-old woman underwent total abdominal hysterectomy/bilateral salpingo-oophorectomy. Her past medical history included idiopathic thrombocytopenic purpura and Marfan's syndrome and past surgery included splenectomy and aortic valve replacement with a three-vessel coronary artery bypass graft. She was converted from Coumadin (DuPont Pharmaceuticals, Wilmington, Delaware) to heparin preoperatively, and heparin was stopped six hours before surgery, with normalization of her prothrombin time (PT) and partial thromboplastin time (PTT). Topical bovine thrombin spray was applied to the surgical field in anticipation of early resumption of heparin anticoagulation. Seven days after surgery, after recovering from some acute bleeding problems, the patient began to have elevation of her PT in spite of being off Coumadin for 10 days. Her PT and international normalized ratio (INR) continued to rise, reaching peak values of 31.4 and 6.99, respectively. A mixing study did not correct the problem, confirming the presence of coagulation inhibitors. The patient was given intravenous immunoglobulins and corticosteroids, and her PT/PTT and INR values slowly normalized. CONCLUSION: Acquired coagulation factor may develop following gynecologic surgery with topical thrombin use. This potential complication should be strongly considered in any patient prior to using topical bovine thrombin, especially those with a prior exposure or history of surgical procedures in which bovine thrombin is commonly used.  相似文献   
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Five cases of proved syphilitic endocarditis or aortitis, with superimposed bacterial vegetations, have been presented. In none of the cases were both diagnoses made clinically. In all five cases the blood Wassermann and Kahn reactions were positive. In four cases blood cultures were positive, and in the fifth case Streptococcus viridans was grown from the vegetation on the heart valve.Streptococcus viridans was recovered in four of the cases and Streptococcus hemolyticus in the remaining case. In three of the cases embolic phenomena were prominent, and in two the mesenteric vessels were involved. In one case there were multiple saccular mycotic aneurysms of the membranous septum and aortic cusps. In another case a fairly characteristic syphilitic aortic valvulitis and aortitis were associated with a typical rheumatic involvement of the mitral valve.The diagnosis of syphilitic aortitis and valvulitis does not exclude the possibility of superimposed bacterial involvement, as shown by the above cases, although the lesion undoubtedly is rare. This diagnosis should be considered clinically whenever there is a combination of sepsis of undetermined origin, a positive Wassermann reaction, and evidence of aortic insufficiency or aortitis, without evidence of previous rheumatic infection.  相似文献   
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