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1.
2.
Aoife De Brún Liran Shan Áine Regan Áine McConnon Patrick Wall 《Health communication》2016,31(10):1235-1241
The 2008 dioxin crisis occurred as a result of contamination of Irish pork. The event had significant implications for Ireland’s economy and the reputation of its agricultural industry, as well as raising concerns for human health. This study describes the results of a content analysis of Irish and UK newspaper coverage of the 2008 Irish dioxin crisis, as this is likely to provide insight into how public perceptions of this issue were shaped. Articles from 16 print publications were systematically sampled for the period December 2008 to February 2009. The resulting data set of 141 articles was examined using a coding protocol developed based on previous research and refined during piloting. Results indicated that the dioxin crisis was primarily portrayed by the media as an industry/economic crisis, dominant in 26.9% of articles in the sample. Within this dominant portrayal, the agricultural industry was frequently cited as being in crisis (42.6%); however, the implications of the crisis on the wider economic environment also received attention (17.7%). Differences between Irish and UK-based media were also examined, revealing that while the Irish media most frequently described the crisis in terms of its impact on the industry and economy, the UK media were more likely to portray the crisis as a risk to health. These dominant media messages and message framings have implications for the public understanding of the issue in each country and potential consequences regarding perception of the adequacy of existing food policy and regulatory oversight. 相似文献
3.
Saskia L.M.A. Beeres MD Katja Zeppenfeld MD Jeroen J. Bax MD Petra Dibbets-Schneider Marcel P.M. Stokkel MD Willem E. Fibbe MD Ernst E. van der Wall MD Douwe E. Atsma MD Martin J. Schalij MD 《Heart rhythm》2007,4(3):257-265
BACKGROUND: Bone marrow cell injection has been introduced to treat patients with ischemic heart disease. However, focal application of bone marrow cells may generate an arrhythmogenic substrate. OBJECTIVES: To assess the electrophysiological and arrhythmogenic effects of intramyocardial bone marrow cell injection in patients with chronic myocardial ischemia. METHODS: Bone marrow was aspirated in 20 patients (65+/-11 years, 19 male) with drug-refractory angina and myocardial ischemia. Electroanatomical mapping (NOGA, Biosense-Webster, Waterloo, Belgium) was performed during mononuclear cell isolation. Areas for cell injection were selected based on the localization of ischemia on SPECT. These areas were mapped in detail to evaluate local bipolar electrogram duration, amplitude and fragmentation. Mononuclear cells were injected in the ischemic area with the NOGA system. SPECT and electroanatomical mapping were repeated at 3 months. Holter monitoring was repeated at 3 and 6 months. RESULTS: SPECT revealed a decrease in the number of segments with ischemia (3.5+/-2.5 vs. 1.1+/-1.0 at 3 months; P<0.01) and an increased left ventricular ejection fraction (44+/-13% vs. 49+/-17% at 3 months; P=0.02). The number of ventricular premature beats remained unchanged (10+/-24x10(2)/24h vs. 8+/-23x10(2)/24h at 3 months (P=NS) and 12+/-30x10(2)/24h at 6 months (P=NS)). At 3 months follow-up, bone marrow cell injection did not prolong electrogram duration (15.9+/-4.6 ms vs. 15.6+/-4.0 ms; P=NS), decrease electrogram amplitude (3.8+/-1.5 mV vs. 3.8+/-1.5 mV; P=NS), or increase fragmentation (2.0+/-0.5 vs. 1.9+/-0.4; P=NS). CONCLUSION: Intramyocardial bone marrow cell injection does not increase the incidence of ventricular arrhythmias and does not alter the electrophysiological properties of the injected myocardium. 相似文献
4.
A de Roos J Doornbos S Rebergen P van Rugge P Pattynama E E van der Wall 《European journal of radiology》1992,14(2):97-103
Recent advances in cardiovascular applications of magnetic resonance (MR) imaging and phosphorus-31 spectroscopy are reported. MR velocity mapping is a valuable adjunct to conventional imaging techniques, providing information on flow velocities as well as on absolute blood flow volume in the aorta and pulmonary arteries. Recently, ultrafast MR techniques have become available to evaluate myocardial perfusion with the aid of MR contrast agents as perfusion marker. Dynamic MR imaging is a powerful tool to assess cardiac function and ventricular mass. In particular, right ventricular function and mass can be evaluated with great accuracy, contributing to improved assessment of the significance of disease processes which may affect the right heart. The role of phosphorus-31 spectroscopy of the heart is expanding for the evaluation of ischemic myocardial disease and cardiomyopathies. The phosphocreatine to adenosine triphosphate ratio appears to be a marker of disease in patients with cardiac hypertrophy. In conclusion, MR imaging and phosphorus-31 spectroscopy is gaining widespread acceptance for evaluation of many cardiovascular disease processes. 相似文献
5.
6.
G. Aernout Somsen Ernst E. van der Wall Bob van Vlies Judocus J. J. Borm Eric A. van Royen 《The International Journal of Cardiac Imaging》1996,12(4):305-310
In patients with chronic heart failure, increased sympathetic activity and cardiac sympathetic neuronal dysfunction are present and have been related to unfavourable clinical outcome. Modification of these alterations with the objective to improve prognosis has become an important aim of pharmacological therapy for these patients. A noninvasive technique to assess sympathetic neuronal function at the cardiac level may be valuable in evaluating newly developed therapeutic strategies. 123-iodine metaiodobenzylguanidine can be used visualize cardiac sympathetic nerve function and activity. Single photon emission computerized tomographic is preferred to planar scintigraphy since it does not depend on superposition of other anatomical structures and may allow assessment of regional cardiac 123-iodine metaiodobenzylguanidine uptake. Although the quantitation of cardiac uptake in these tomographic images has several limitations, the use of the left ventricular cavity as a reference, calibrated by the 123-iodine activity in a blood sample drawn at the time of acquisition, may have clinical applications, with respect to the evaluation of therapeutical intervention in patients with heart failure.Abbreviations BS
blood sample
- CD
count density
- dP/dt
change in pressure over time
- [123I]
123-iodine
- Km
affinity constant
- MIBG
metaiodobenzylguanidine
- MBq
mega Bequerel
- SPECT
single photon emission computerized tomography
- Vm
capacity constant 相似文献
7.
Coronary vasomotion in patients with syndrome X: evaluation with positron emission tomography and parametric myocardial perfusion imaging 总被引:1,自引:1,他引:0
Joan G. Meeder Paul K. Blanksma Ernst E. van der Wall Antoon T. M. Willemsen Jan Pruim Rutger L. Anthonio Richard M. de Jong Willem Vaalburg Kong I. Lie 《European journal of nuclear medicine and molecular imaging》1997,24(5):530-537
The aim of this study was to elucidate further the causative mechanism of abnormal coronary vasomotion in patients with syndrome X. In patients with syndrome X, defined as angina pectoris and documented myocardial ischaemia during stress testing with normal findings at coronary angiography, abnormal coronary vasomotion of either the micro- or the macrocirculation has been suggested as the causative mechanism. Accordingly, we evaluated endothelial function, vasodilator reserve, and perfusion heterogeneity in these patients. Twenty-five patients with syndrome X (definitely normal coronary arteriogram, group A), 15 patients with minimal coronary artery disease (group B) and 21 healthy volunteers underwent [13N]ammonia positron emission tomography at rest, during cold pressor stimulation (endothelial function) and during dipyridamole stress testing (vasodilator reserve). Heterogeneity of myocardial perfusion was analysed by parametric polar mapping using a 480-segment model. In both patient groups, resting perfusion was increased compared to the normal subjects: group A, 127±31 ml·min–1·100 g–1; group B, 124±30 ml·min–1·100 g–1 normal subjects, 105±21 ml·min–1·100 g–1 (groups A and B vs normals,P<0.05). These differences were abolished after correction for rate-pressure product. During cold pressor stimulation, the perfusion responses (ratio of cold pressor perfusion to resting perfusion) were similar among the patients and the control subjects (group A, 1.20±0.23; group B, 1.24±0.22; normal subjects, 1.23±0.14). Likewise, during dipyridamole stress testing, perfusion responses were similar among the three groups (group A, 2.71±0.67; group B, 2.77±1.29; normal subjects, 2.91±1.04). In group A the heterogeneity of resting perfusion, expressed as coefficient of variation, was significantly different from the volunteers (20.1±4.5 vs 17.0±3.0,P<0.05). In group B (coefficient of variation 19.4±3.9) the difference from normal volunteers was not significant. In this study, patients with syndrome X and patients with minimal coronary artery disease showed normal perfusion responses during cold pressor stimulation and dipyridamole stress testing. Our findings therefore suggest that endothelial dysfunction and impaired vasodilator reserve are of no major pathophysiological relevance in patients with syndrome X. Rather, other mechanisms such as increased sympathetic tone and focal release of vasoactive substances may play a role in the pathogenesis of syndrome X. 相似文献
8.
Prevalence of antibody to human T-cell lymphotropic virus type I/II in people of Caribbean origin in Toronto.
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J Chiavetta J Nusbacher F Tam A Wall J Steaffens H Lee 《Canadian Medical Association journal》1992,147(10):1493-1498
OBJECTIVE: To estimate the prevalence of antibody to human T-cell lymphotropic virus type I/II (anti-HTLV-I/II) in people from an HTLV-I/II-endemic area (the Caribbean) living in a nonendemic region (Canada). DESIGN: Cross-sectional household survey. SETTING: Households in Toronto in 1989. PARTICIPANTS: A modified quota sampling method was used to recruit subjects of Caribbean origin as well as other Canadians. Of 2900 people invited to participate in the study 1323, 743 of Caribbean origin, were interviewed about their background and possible exposure to HTLV-I/II. MAIN OUTCOME MEASURES: Blood samples were analysed for anti-HTLV-I/II by means of an enzyme-linked immunoassay, the result being confirmed by the Western blot technique and radioimmunoprecipitation assay. The samples were also analysed for antibody to human immunodeficiency virus (anti-HIV) and hepatitis B surface antigen (HBsAg) and for surrogate markers of non-A, non-B hepatitis. RESULTS: A total of 853 blood samples (64.5%) were analysed, 483 (56.6%) from subjects of Caribbean origin. The proportion of subjects who agreed to give a blood sample was similar for the Caribbean and non-Caribbean strata. Eleven subjects, all of Caribbean origin (2.3% of the Caribbean stratum), were confirmed to be positive for anti-HTLV-I/II. There were no significant differences between the antibody-positive and antibody-negative subjects with respect to sex, age, racial origin or residence in the Caribbean for at least 22 years. All anti-HTLV-I/II-positive subjects were negative for anti-HIV and HBsAg, and four (36.4%) were positive for antibody to HBsAg and to hepatitis B core antigen. CONCLUSIONS: Except for origin, an association between antibody positivity and other factors could not be demonstrated. The findings suggest that blood donor screening might include place of origin in addition to the usual lifestyle or behavioural factors. However, the need to ensure safety of transfusion must be balanced against the need for participation of all groups in the blood transfusion program. 相似文献
9.
Canadian National Breast Screening Study: 1. Breast cancer detection and death rates among women aged 40 to 49 years. 总被引:17,自引:8,他引:9
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OBJECTIVES: To evaluate the efficacy of the combination of annual screening with mammography, physical examination of the breasts and the teaching of breast self-examination in reducing the rate of death from breast cancer among women aged 40 to 49 years on entry. DESIGN: Individually randomized controlled trial. SETTING: Fifteen urban centres in Canada with expertise in the diagnosis and treatment of breast cancer. PARTICIPANTS: Women with no history of breast cancer and no mammography in the previous 12 months were randomly assigned to undergo either annual mammography and physical examination (MP group) or usual care after an initial physical examination (UC group). The 50,430 women enrolled from January 1980 through March 1985 were followed for a mean of 8.5 years. DATA COLLECTION: Derived from the participants by initial and annual self-administered questionnaires, from the screening examinations, from the patients' physicians, from the provincial cancer registries and by record linkage to the Canadian National Mortality Data Base. Expert panels evaluated histologic and death data. MAIN OUTCOME MEASURES: Rates of referral from screening, rates of detection of breast cancer from screening and from community care, nodal status, tumour size, and rates of death from all causes and from breast cancer. RESULTS: Over 90% of the women in each group attended the screening sessions or returned the annual questionnaires, or both, over years 2 to 5. The characteristics of the women in the two groups were similar. Compared with the Canadian population, the participants were more likely to be married, have fewer children, have more education, be in a professional occupation, smoke less and have been born in North America. The rate of screen-detected breast cancer on first examination was 3.89 per 1000 in the MP group and 2.46 per 1000 in the UC group; more node-positive tumours were found in the MP group than in the UC group. During years 2 through 5 the ratios of observed to expected cases of invasive breast cancer were 1.26 in the MP group and 1.02 in the UC group. Of the women with invasive breast cancer through to 7 years, 191 and 157 women in the MP and UC groups respectively had no node involvement, 55 and 43 had one to three nodes involved, 47 and 23 had four or more nodes involved, and 38 and 49 had an unknown nodal status. There were 38 deaths from breast cancer in the MP group and 28 in the UC group. The ratio of the proportions of death from breast cancer in the MP group compared with those in the UC group was 1.36 (95% confidence interval 0.84 to 2.21). The survival rates were similar in the two groups. The highest survival rate occurred among women whose cancer had been detected by mammography alone. CONCLUSION: The study was internally valid, and there was no evidence of randomization bias. Screening with yearly mammography and physical examination of the breasts detected considerably more node-negative, small tumours than usual care, but it had no impact on the rate of death from breast cancer up to 7 years' follow-up from entry. 相似文献
10.
A cohort study of workers at a smeltery in northern Sweden showed an excess mortality, mostly due to deaths in cancer (especially in the respiratory organs) and circulatory diseases. Further follow-up of the cohort showed a decreasing trend in lung cancer incidence and mortality. The cohort studied has now been expanded and comprises 6,334 blue-collar workers first employed 1928-1979. They were followed in the cancer register up to 1987-01-01 and in the cause-of-death register up to 1988-01-01. The decreasing trend in lung cancer incidence and mortality continued but there was still an elevated lung cancer incidence among the workers when compared with Swedish males. The cumulative occurrence of lung cancer since time of first employment was analyzed by different employment cohorts and a higher occurrence of lung cancer was found among those earlier employed. 相似文献