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101.
This study analysed a sample of food advertisements shown during 63 hours of children's programming to investigate compliance and non‐compliance with one of the Australian Children's Television Standards (CTS): CTS 20.2a. This standard regulates the way premium offers may, and may not, be used to sell products to children. Of the 1721 advertisements contained in the sample, 544 (32%) were for food. A significantly higher number of food advertisements (41%) were shown during ‘C’ programs (which are specifically regulated and produced for children six to 13 years of age and suitable for viewing without adult supervision), compared with 30% during the less regulated ‘G’ programs (P= < 0.001) (suitable for children to view without adult supervision but not produced specifically for a child audience). Over one‐third of food advertisements (36%) in ‘C’ time contained a premium offer compared with 17% in ‘G’ time (P= < 0.0001). Using a precisely defined interpretation of CTS 20.2a, this study found 30 (31%) of food advertisements breached the standard during ‘C’ programs. This was a significantly higher proportion than the 54 (12%) of breaches in ‘G’ time (P= < 0.0001). From this study, the current regulatory system has not resulted in more responsible food advertising during ‘C’ programs, and the widespread breaches of CTS 20.2a indicate this standard is ineffective as a means of regulating food advertising. The Australian Broadcasting Authority has recognised that children need protection from unfair marketing practices and the improper use of premium offers to promote a food product, therefore CTS 20.2a needs urgent review to make it more effective. 相似文献
102.
Anthony D Harris Yehuda Carmeli Matthew H Samore Keith S Kaye Eli Perencevich 《Infection control and hospital epidemiology》2005,26(4):342-345
BACKGROUND: Case-control studies often analyze risk factors for antibiotic resistance. Recently published articles have illustrated that randomly selected control-patients may be preferable to those with the susceptible phenotype of the organism. A possible methodologic problem with randomly selected control-patients is potential bias due to control group misclassification. This occurs if some control-patients did not have clinical cultures performed and thus might have been unidentified case-patients. If this bias exists, these studies might be expected to report lower odds ratios (ORs) because control-patients would be more like case-patients. OBJECTIVE: To analyze potential biases that might arise due to control group misclassification and potentially larger selection biases that may be introduced if control-patients are required to have at least one clinical culture. PATIENTS: One hundred twenty case-patients, 770 control-patients in group 1, and 510 control-patients in group 2. METHODS: Two case-control studies. Case-patients had clinical cultures positive for imipenem-resistant Pseudomonas aeruginosa. The first group of control-patients were random. The second group of control-patients were identical to those in group 1 except being required to have at least one clinical culture. RESULTS: Univariate analyses showed higher ORs for case-patients versus control-patients in group 1 (imipenem [OR, 12.5], piperacillin-tazobactam [OR, 3.7], and vancomycin [OR, 4.7]) as compared with case-patients versus control-patients in group 2 (imipenem [OR, 8.0], piperacillin-tazobactam [OR, 2.5], and vancomycin [OR, 3.0]). CONCLUSION: Requiring control-patients to have at least one clinical culture introduces a selection bias likely because it eliminates patients with less severe illness. 相似文献
103.
Keith S Kaye Anthony D Harris Matthew Samore Yehuda Carmeli 《Infection control and hospital epidemiology》2005,26(4):346-351
OBJECTIVE: There are significant limitations of the standard case-control study design for identifying risk factors for resistant organisms. The objective of this study was to develop a study design to overcome these limitations. DESIGN: Theoretical analysis of different types of study designs that can be used in risk factor studies for resistant organisms. RESULTS: We developed the case-case-control study design, which uses two separate case-control analyses within a single study. The first analysis compares patients infected with resistant bacteria (resistant cases) with control-patients without infection caused by the target organism, who are therefore representative of the source population; and the second analysis compares patients infected with the susceptible phenotype of the target organism (susceptible cases) with the same control-patients without infection caused by the target organism. These two analyses provide risk models for (1) isolation of the resistant phenotype of the target organism as compared with the source population and (2) isolation of the susceptible phenotype of the organism as compared with the source population. When these two risk models are compared and contrasted, risk factors specifically associated with isolation of the resistant phenotype can be identified. CONCLUSIONS: The case-case-control study design is an effective method for identifying risk factors for antimicrobial-resistant pathogens. Although the case-case-control study design has limitations, it is, in our opinion, more informative and less flawed than the standard case-control study design. 相似文献
104.
Effects of remifentanil on neutrophil adhesion, transmigration, and intercellular adhesion molecule expression 总被引:2,自引:0,他引:2
Hofbauer R Frass M Gmeiner B Sandor N Schumann R Wagner O Kaye AD 《Acta anaesthesiologica Scandinavica》2000,44(10):1232-1237
BACKGROUND: Anaesthetic drugs are used for pain therapy and anaesthesia. Neutrophils play a significant role during the process of inflammation. The aim of the current study was to investigate the effects of remifentanil and fentanyl on neutrophil migration through endothelial cell monolayers, and on adhesion molecule expression. METHODS: After isolation of polymorphonuclear neutrophils (PMNL) we used a currently described migration assay. PMNL and/or endothelial cell monolayers (ECM) were pre-treated with remifentanil using clinically relevant, as well as higher and lower concentrations or relevant concentrations of fentanyl. RESULTS: Concentrations of remifentanil (50 ng/mL) similar to the relevant plasma concentration were able to inhibit PMNL migration through ECM significantly (migration compared to the control 82+/-7% SD; P<0.05), when both cell types were treated with the synthetic narcotic remifentanil. Fentanyl (30 ng/mL) showed a stronger inhibitory effect (migration compared to the control 67+/-9.2%; P<0.05). Endothelial cell adhesion molecule expression was reduced after either remifentanil or fentanyl. CONCLUSION: The results of the present investigation indicate that remifentanil influences interaction of ECM against human neutrophils. Compared to fentanyl, remifentanil seems to exhibit minor inhibitory effects on neutrophil migration. 相似文献
105.
Our goal was to determine and predict the effects of temperature, shear rate, hematocrit, and different volume expanders on blood viscosity in conditions mimicking deep hypothermia for cardiac operations. Blood was obtained from six healthy adults. Dilutions were prepared to hematocrits of 35%, 30%, 22.5%, and 15% using plasma, 0.9% NaCl, 5% human albumin, and 6% hydroxyethyl starch. Viscosity was measured over a range of shear rates (4.5-450 s(-1)) and temperature (0 degrees -37 degrees C). A parametric expression for predicting blood viscosity based on the study variables was developed, and its agreement with measured values tested. Viscosity was higher at low shear rates and low temperatures, especially at temperatures less than 15 degrees C (P: < 0.016 for all conditions in comparison with 37 degrees C). Decreasing hematocrit, especially to less than 22.5%, decreased viscosity. Hemodilution with albumin or 0.9% NaCl decreased blood viscosity more than hemodilution with plasma or 6% hydroxyethyl starch (P: < 0.01 for all cases). The derived mathematical model for viscosity as a function of temperature, hematocrit, shear rate, and diluent predicted viscosity values that correlated well with the measured values in experimental samples (r(2) > 0.92, P: < 0.001). IMPLICATIONS: A theoretical model for blood viscosity predicted independent effects of temperature, shear rate, and hemodilution on viscosity over a wide range of physiologic conditions, including thermal extremes of deep hypothermia in an experimental setting. Moderate hemodilution to a hematocrit of 22% decreased blood viscosity by 30%-50% at a blood temperature of 15 degrees C, suggesting the potential to improve microcirculatory perfusion during deep hypothermia. 相似文献
106.
Bowers KW Edmonds JL Girod DA Jayaraman G Chua CP Toby EB 《The Journal of bone and joint surgery. American volume》2000,82(5):694-704
BACKGROUND: Osteocutaneous radial forearm free flaps have fallen from favor due to pathological fractures of the radius. The purposes of this study were to propose a means to decrease the rate of pathological fracture by prophylactic fixation of the donor-site defect and to evaluate this technique biomechanically. METHODS: Two groups of ten matched pairs of fresh-frozen cadaveric radii were harvested. In Group 1, an eight-centimeter length of radius comprising 50 percent of the cross-sectional area of the bone was removed to simulate an osteocutaneous radial forearm donor-site defect. This defect was created in one member of each pair, with the other bone in the pair left intact. In Group 2, both members of the ten matched pairs of radii had identical defects created as previously described. However, one radius in each pair had a twelve-hole, 3.5-millimeter dynamic compression plate placed across the segmental defect. In each group, five matched pairs were tested to failure in torsion and five matched pairs were tested to failure in four-point bending. RESULTS: In Group 1, the intact radius was a mean of 5.7 times stronger in torsion and 4.2 times stronger in four-point bending than the radius with the segmental resection. In Group 2, the radius that was ostectomized and fixed with a plate was a mean of 4.0 times stronger in torsion and 2.7 times stronger in four-point bending than the ostectomized radius. CONCLUSIONS: Removal of an eight-centimeter segment from the radius dramatically decreased both torsion and bending strength. Application of a plate over the defect in the radius significantly restored the strength of the radius (p = 0.01). 相似文献
107.
Lactic acidosis, a rare but life-threatening condition is fairly common in HIV-infected individuals. The cause of lactic acidosis appears to stem from the use of HAART, causing mitochondrial dysfunction and the depletion of flavoprotein cofactors necessary for electron transport. Deficiencies of riboflavin or thiamin can contribute to the development of hyperlactic acidemia. Further, the high incidence of liver disease (hepatitis B or C and alcoholic liver disease) in this population predisposes HIV patients to metabolic abnormalities. Supplementation with thiamin or riboflavin, depending on the individual patient's condition, can reduce elevated lactic acid levels. 相似文献
108.
Study OBJECTIVE: To estimate the incidence of lower limb fractures in the United Kingdom and assess the relative importance of various risk factors for lower limb fractures. DESIGN: Cohort analysis and matched case-control study. SETTING: General practices contributing information to the General Practice Research Database. SUBJECTS: Individuals registered with these general practices who were at risk for a first time lower limb fracture from 1 January 1990 to 31 December 2001. MAIN OUTCOME MEASURES: Age, sex, and fracture site specific incidence rates; relative risks and population attributable risks for various medical risk factors. RESULTS: Overall, the risk of lower limb fracture was 17% higher in women then in men. Within age groups, men and women had generally similar proportions of fractures at specific sites in the lower limb. Among the risk factors evaluated, road collisions were associated with the highest relative risk for lower limb fracture, but only accounted for 3.1% or less of the population attributable risk for specific fracture types in any age group. The relative risk for lower limb fracture associated with a diagnosis of dementia was 2.3 (95% confidence interval 2.0 to 2.6), while relative risk estimates for other medical diagnoses were less than 2. Fracture risk was increased among current users of corticosteroids, antipsychotics, antidepressants, and hypnotic/sedatives, but the population attributable risks for each of these drug classes within fracture and age specific strata were only 3.0% or less. CONCLUSIONS: Many risk factors for lower limb fracture have been identified, but population attributable risk estimates for various risk factors are small. These findings suggest that multifactorial prevention programs are needed to decrease the incidence of lower limb fractures in the general population. 相似文献
109.
Graham G Dark A Hilary Calvert Robert Grimshaw Christopher Poole Ken Swenerton Stan Kaye Robert Coleman Gordon Jayson Tien Le Susan Ellard Marc Trudeau Paul Vasey Marta Hamilton Terri Cameron Emma Barrett Wendy Walsh Lynn McIntosh Elizabeth A Eisenhauer 《Journal of clinical oncology》2005,23(9):1859-1866
PURPOSE: Liposomal lurtotecan (OSI-211) is a liposomal formulation of the water-soluble topoisomerase I inhibitor lurtotecan (GI147211), which demonstrated superior levels of activity compared with topotecan in preclinical models. We studied two schedules of OSI-211 in a randomized design in relapsed ovarian cancer to identify the more promising of the two schedules for further study. PATIENTS AND METHODS: Eligible patients had measurable epithelial ovarian, fallopian, or primary peritoneal cancer that was recurrent after one or two prior regimens of chemotherapy. Patients were randomly assigned to receive either arm A (OSI-211 1.8 mg/m(2)/d administered by 30-minute intravenous infusion on days 1, 2, and 3 every 3 weeks) or arm B (OSI-211 2.4 mg/m(2)/d administered by 30-minute intravenous infusion on days 1 and 8 every 3 weeks). The primary outcome measure was objective response, which was confirmed by independent radiologic review, and a pick the winner statistical design was used to identify the schedule most likely to be superior. RESULTS: Eighty-one patients were randomized between October 2000 and September 2001. The hematologic toxic effects were greater on arm A than on arm B (grade 4 neutropenia, 51% v 22%, respectively), as was febrile neutropenia (26% v 2.4%, respectively). Of the 80 eligible patients, eight patients (10%) had objective responses; six responders (15.4%; 95% CI, 6% to 30%) were in arm A and two responders (4.9%; 95% CI, 1% to 17%) were in arm B. CONCLUSION: The OSI-211 daily for 3 days intravenous schedule met the statistical criteria to be declared the winner in terms of objective response. This schedule was also associated with more myelosuppression than the schedule of OSI-211 administered in arm B. 相似文献