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991.
What the public thinks about the tobacco industry and its products   总被引:1,自引:0,他引:1  
Objectives: To assess public attitudes toward the tobacco industry and its products, and to identify predictors of attitudes supportive of tobacco industry denormalisation.

Design: Population based, cross sectional survey.

Setting: Ontario, Canada.

Subjects: Adult population (n = 1607).

Main outcome measures: Eight different facets of tobacco industry denormalisation were assessed. A denormalisation scale was developed to examine predictors of attitudes supportive of tobacco industry denormalisation, using bivariate and multivariate analyses.

Results: Attitudes to the eight facets of tobacco industry denormalisation varied widely. More than half of the respondents supported regulating tobacco as a hazardous product, fining the tobacco industry for earnings from underage smoking, and suing tobacco companies for health care costs caused by tobacco. Majorities also thought that the tobacco industry is dishonest and that cigarettes are too dangerous to be sold at all. Fewer than half of the respondents thought that the tobacco industry is mostly or completely responsible for the health problems smokers have because of smoking and that tobacco companies should be sued for taxes lost from smuggling. In particular, less than a quarter thought that the tobacco industry is most responsible for young people starting to smoke. Non-smoking, knowledge about health effects caused by tobacco, and support for the role of government in health promotion were independent predictors of support for tobacco industry denormalisation.

Conclusions: Although Ontarians are ambivalent toward tobacco industry denormalisation, they are supportive of some measures. Mass media programmes aimed at increasing support for tobacco industry denormalisation and continued monitoring of public attitudes toward this strategy are needed.

  相似文献   
992.
Pacific salmon were introduced to the Great Lakes in the 1960s and now support major recreational fishery. Population declines resulting from invasive species have prompted agencies to consider diversifying sport fisheries through stocking. Atlantic salmon are native to Lake Ontario, but a small fishery has developed in northern Lake Huron since the 1990s that appears suited to the Lake Huron food web leading to requests for increased stocking by anglers and consideration by agencies. However, no study has evaluated the trophic ecology of Atlantic salmon in relation to other salmonine predators in northern Lake Huron. In this study, we used stable isotopes of carbon (δ13C) and nitrogen (δ15N), along with mercury (Hg) concentrations to assess resource use, niche overlap, and contaminant accumulation in Atlantic salmon compared to select Lake Huron predators. Atlantic salmon exhibited considerable niche overlap with Chinook and coho salmon but were strongly differentiated from lake trout. In addition, we observed that Atlantic salmon had similar Hg concentrations as coho but were lower than both Chinook salmon and lake trout. Based upon the relationship between fish size, δ15N, and Hg, Atlantic salmon bioaccumulate Hg similarly to Pacific salmon but likely have lower consumptive demands than Chinook salmon. Continued attention should be placed on understanding how Atlantic salmon fit into the current Lake Huron food web in order to evaluate the long-term efficacy of the Atlantic salmon stocking program.  相似文献   
993.
Dreissenid mussel veligers compose a substantial component of pelagic biomass in the Great Lakes, yet their dynamics are poorly understood. To evaluate seasonal, spatial, and inter-annual variation in veliger density, we used a 64-μm mesh plankton net (2008, 2013–2016) and a 153-μm mesh plankton net (2007–2016) to collect dreissenid veligers at nearshore (15–25?m depth), transitional (45?m) and offshore (93–110?m) sites in southeast Lake Michigan during March–December. We also evaluated trends in density of recently settled mussels relative to veliger abundance and the density of the standing stock of adult mussels. Veliger density peaked during both summer and fall at all sites, but peak densities in summer were generally higher nearshore, whereas peak densities in the fall were generally higher offshore. The density of veligers in the 153-μm net was overall 28% of that in the 64-μm net, but there was high variability in this comparison among months. Smaller veligers were much more abundant in the 64-μm net, but there was little difference in the size distribution and abundance between nets for the 210–300?μm size classes. Thus, the 153-μm net could still be a useful tool for assessing density trends of larger veligers just prior to their settlement. Newly settled mussels (≤2?mm) were most abundant in summer or fall at the nearshore and offshore sites but were nearly absent at the transitional site despite the high density of veligers there. Factors other than veliger density must play an important role in mussel recruitment.  相似文献   
994.
Diverse management techniques have been used to mitigate conflicts between humans and double-crested cormorants (Phalacrocorax auritus) including harassment methods supplemented by lethal take. In this study we evaluated impacts of programs to harass spring migrating cormorants on the walleye (Sander vitreus) fishery in Brevoort Lake and the yellow perch (Perca flavescens) and walleye fisheries at Drummond Island. Cormorant foraging declined significantly (p < 0.05) at both locations subsequent to initiation of harassment programs. Overall harassment deterred 90% of cormorant foraging attempts while taking less than 6% lethally on average at each site. Yellow perch were a predominate prey item in number and biomass at both locations. Walleye made up a small proportion of the diet at both locations. However, both walleye and yellow perch abundance increased significantly (p < 0.05) at Drummond Island. Walleye abundance at age 3 increased to record levels in 2008 following 3 years of cormorant management at Brevoort Lake. The estimated cormorant consumption of age-1 walleye in the absence of management at Brevoort Lake during 2005 would account for 55% of the record 2006 age-1 walleye population. These results support the hypothesis that cormorant predation on spawning aggregations of sportfish was a significant mortality factor and cormorant management reduced sportfish mortality and increased abundance at both locations. Continuation of harassment programs and fishery assessments will determine whether improvement of targeted sport fisheries through control of spring migrating cormorants is sustainable.  相似文献   
995.
OBJECTIVES: The objectives of this study were to determine the anatomic and physiological factors most responsible for the severe symptoms and poor prognosis of infants with scimitar syndrome. BACKGROUND: Whereas the diagnosis of scimitar syndrome is often made incidentally in older children and adults who undergo chest radiography for diverse reasons, infants in whom the diagnosis is made typically present with severe symptoms and have a poor prognosis. METHODS: The clinical, catheterization and imaging data of 13 consecutive infants with scimitar syndrome who underwent cardiac catheterization in the 1st 6 months of life were reviewed, with emphasis on the pulmonary artery pressure, pulmonary and cardiovascular anatomy, therapeutic interventions and outcome. RESULTS: Twelve of the 13 infants had pulmonary hypertension at the time of diagnosis. Six patients died despite specific treatment. Eleven of 13 infants had associated cardiac malformations and 9 had large systemic arterial collateral channels to the right lung. Seven patients had anomalies involving the left side of the heart, especially varying degrees of hypoplasia of the left heart or aorta, and six of these patients died. Ten patients underwent surgical or transcatheter therapy in the 1st year of life. Systemic arteries to the right lung were ligated in three patients and occluded by transcatheter embolization in four. Balloon angioplasty was carried out in two patients, one with stenosis of the left-sided pulmonary veins and one with stenosis of the anomalous right pulmonary vein. The latter had placement of a balloon-expandable stent. In both patients, pulmonary vein stenosis progressed. Six patients had surgical repair of associated cardiovascular anomalies, and two required repair of extracardiac congenital anomalies. Occlusion of the anomalous systemic arteries was generally associated with clinical improvement, but congestive heart failure and pulmonary hypertension recurred in those patients with associated cardiovascular anomalies, whose condition subsequently responded after correction of the shunt lesions. CONCLUSIONS: The severe symptoms and pulmonary hypertension found in infants with scimitar syndrome have many causes. Anomalous systemic arterial supply, pulmonary vein stenosis and associated cardiovascular anomalies play a significant role, and the ultimate outcome of individual infants depends on the feasibility of treating these anomalies in early infancy.  相似文献   
996.
PURPOSE: To determine the incidence, natural history, and risk factors associated with myelodysplastic syndrome (MDS) occurring as a late complication following autologous bone marrow transplantation for patients with non-Hodgkin's lymphoma. METHODS: We retrospectively reviewed the charts of all 262 patients who underwent autologous bone marrow transplantation for non-Hodgkin's lymphoma at the Dana-Farber Cancer Institute from 1982 through 1991. Although patients received a variety of treatments before they were eligible for transplant, identical myeloablative therapy (cyclophosphamide 60 mg/kg/d for 2 days plus total-body irradiation twice daily for 3 days) was administered in each case. By collecting data on pretransplant and early posttransplant variables, we attempted to identify risk factors for the development of MDS. RESULTS: The crude overall incidence of posttransplant MDS or acute myeloid leukemia (AML) was 7.6%. The actuarial risk at 6 years was 18% +/- 9%. The median time of onset was 31 months (range, 10 to 101) after transplant or 69 months (range, 27 to 141) after initial treatment for lymphoma. Pretreatment variables predictive for the development of MDS (univariate analysis) included prolonged interval between initial treatment and the transplant procedure (P = .003), increased duration of exposure to chemotherapy (P = .019) or to alkylating agents (P = .045), and use of radiation therapy (P = .032) or pelvic radiation (P = .003) before transplant. CONCLUSION: MDS is a potential complication of autologous bone marrow transplantation for non-Hodgkin's lymphoma; bone marrow stem-cell damage sustained before the transplant may be the most important risk factor.  相似文献   
997.
998.
999.
The stem cell inhibitor, macrophage inflammatory protein-1 alpha (MIP-1 alpha) or LD78, protects multipotent hematopoietic progenitors in murine models from the cytotoxic effects of chemotherapy. Clinical use of human MIP-1 alpha during chemotherapy could therefore lead to faster hematologic recovery and may allow dose intensification. We have also shown that human MIP-1 alpha causes the rapid mobilization of hematopoietic cells, suggesting an additional clinical use in peripheral blood stem cell transplantation. However, the clinical evaluation of human MIP-1 alpha is complicated by its tendency to associate and form high molecular weight polymers. We have produced a variant of rhMIP-1 alpha, BB-10010, carrying a single amino acid substitution of Asp26 > Ala, with a reduced tendency to form large polymers at physiologic pH and ionic strength. This greatly increases its solubility, facilitating its production and clinical formulation. We confirmed the potency of BB-10010 as a human MIP-1 alpha-like agonist in receptor binding, calcium mobilization, inhibition of colony formation, and thymidine suicide assays. The myeloprotective activity of BB-10010 was shown in a murine model of repeated chemotherapy using hydroxyurea. BB-10010 is therefore an ideal variant with which to evaluate the therapeutic potential of recombinant human MIP-1 alpha.  相似文献   
1000.
A person's reality and definition of self are socially constructed; ethnicity is integrally involved in this process. Clinical work is successful if the client constructs a self with a sense of positive self-esteem and empowerment. The profession views social workers' use of self as important in successful clinical work, especially with clients ethnically different from themselves. This article provides a framework adapted from a constructivist perspective for the clinician's skillful use of self in therapeutic discourse. The framework consists of five stances the clinician can use in transcending the discomfort he or she may experience in a cross-cultural clinical situation. Use of these stances facilitates clients' ethnic validation, which is essential to positive therapeutic outcomes. This article uses case examples to illustrate the use of the framework.  相似文献   
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