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981.
982.
Wei Yue Steven J. Santner Shigeru Masamura Ji-Ping Wang Laurence M. Demers Christopher Hamilton Richard J. Santen 《Breast cancer research and treatment》1998,49(1):S1-S7
Estradiol stimulates the growth of breast tumor cells in both pre- and post menopausal women. Following the menopause, the levels of estradiol in breast tumor tissues are similar to those from tumors obtained prior to cessation of ovarian function, even though plasma estrogen levels are 10–50 fold lower in post- than in premenopausal women. These observations suggested the possibility of enhanced estradiol uptake from plasma or in situ synthesis in post-menopausal women. We systematically studied these possibilities in a series of model systems. Initially we demonstrated a very high affinity estradiol binding site in tissues from castrated rats. Enhanced uptake occurred under conditions of low plasma estrogen levels when compared to animals with higher estradiol levels. In situ synthesis also occurred both through the sulfatase and aromatase pathways. In further studies, we compared uptake from plasma with in situ synthesis via aromatase in a nude mouse model. Under the conditions utilized, in situ synthesis resulted in much higher tissue estradiol levels and tumor growth rates than did uptake from plasma. During these studies we demonstrated that tumors deprived of estradiol developed mechanisms rendering them more sensitive to estrogen. This involved the ability of cells to adapt to estradiol deprivation to allow them to be responsive to four log lower amounts of estrogen than when studied under wild type conditions. In addition, cells adapted by increasing their level of aromatase and thus developing the capability to become more sensitive to estrogen precursors. Taken together, these studies demonstrate that breast cancer tissue is highly plastic and can adapt to conditions of estrogen deprivation via a variety of mechanisms. 相似文献
983.
984.
Smoking practices in New York City: The use of a population-based survey to guide policy-making and programming 总被引:4,自引:0,他引:4
Farzad Mostashari Bonnie D. Kerker Anjum Hajat Nancy Miller Thomas R. Frieden 《Journal of urban health》2005,82(1):58-70
To inform New York City’s (NYC’s) tobacco control program, we identified the neighborhoods with the highest smoking rates,
estimated the burden of second-band smoke exposure, assessed the early response to state taxation, and examined cessation
practices. We used a stratified random design to conduct a digit-dialed telephone survey in 2002 among 9,674 New York City
adults. Our main outcome measures included prevalence of cigarette smoking, exposure to second-hand smoke, the response of
smokers to state tax increases, and cessation practices. Even after controlling for sociodemographic factors (age, racelethnicity,
income, education, marital status, employment status, and foreign-born status) smoking rates were highest in Central Harlem
and in the South Bronx. Sixteen percent of nonsmokers reported frequent exposure to second-hand smoke at home or in a workplace.
Among smokers with a child with asthma, only 33% reported having a no-smoking policy in their homes. More than one fifth of
smokers reported reducing the number of cigarettes they smoked in response to the state tax increase. Of current smokers who
tried to quit, 65% used no cessation aid. These data were used to inform New York City’s smoke-free legislation, taxation,
public education, and a free nicotine patch give-away program. In conclusion, large, local surveys can provide essential data
to effectively advocate for, plan, implement, and evaluate a comprehensive tobacco control program.
Dr. Mostashari (the guarantor) made substantial contributions to the conception, design, and supervision of this paper, the
analysis and interpretation of data, the drafting of the paper, critical revisions of the paper for important intellectual
content, and the acquisition of data and funding for this research. Dr. Kerker made substantial contributions to the analysis
and interpretation of data, the drafting of the paper and critical revisions of the paper for important intellectual content.
Ms. Hajat made substantial contributions to the acquisition of data and critical revisions of the paper for important intellectual
content. Dr. Miller made substantial contributions to the conception of this paper and critical revisions of the paper for
important intellectual content. Dr. Frieden made substantial contributions to the conception, design, and supervision of this
paper and critical revisions of the paper for important intellectual content. 相似文献
985.
Viroj Wiwanitkit 《Sexuality and disability》2005,23(1):41-46
The incidence of sexual assault continues to escalate, and it is under-reported. Recent literature discusses the medical, legal, and psychological management of the female sexual assault victim, but little has been written regarding appropriate management of male sexual assault. This article focuses on the laboratory investigation in male rape case. 相似文献
986.
Bruce Simons-Morton Denise Haynie Keith Saylor Aria Davis Crump Rusan Chen 《Prevention science》2005,6(3):187-197
This study evaluated the effects of a school-based intervention on growth trajectories of smoking, drinking, and antisocial
behavior among early adolescents. Seven middle schools were randomized to intervention or comparison conditions and students
in two successive cohorts (n = 1484) provided five waves of data from sixth to ninth grade. The Going Places Program, included classroom curricula, parent
education, and school environment components. Latent growth curve analyses demonstrated significant treatment group effects,
including reducing increases in friends who smoke, outcome expectations for smoking, and smoking progression, but had non-significant
effects on drinking or antisocial behavior. The Going Places Program was effective in preventing increases in smoking progression,
but its efficacy as a more cross-cutting problem behavior preventive intervention was not confirmed. 相似文献
987.
The potential use of genetic tests in insurance has raised concerns about discrimination and individuals losing access to health care either because of refusals to test for treatable diseases, or because test-positives cannot afford premiums. Governments have so far largely sought to restrict the use of genetic information by insurance companies. To date the number of tests available with significant actuarial value is limited. However, this is likely to change, raising more clearly the question as to whether the social costs of adverse selection outweigh the social costs of individuals not accessing health care for fear of the consequences of test information being used in insurance markets. In this contribution we set out the policy context and model the potential trade-offs between the losses faced by insurers from adverse selection by insurees (which will increase premiums reducing consumer welfare) and the detrimental health effects that may result from persons refusing to undergo tests that could identify treatable health conditions. It argues that the optimal public policy on genetic testing should reflect overall societal benefit, taking account of these trade-offs. Based on our model, the factors that influence the outcome include: the size of and value attached to the health gains from treatment; deterrent effects of a disclosure requirement on testing for health reasons; incidence of the disease; propensity of test-positives to adverse select; policy value adverse selectors buy in a non-disclosure environment; and price elasticity of demand for insurance. Our illustrative model can be used as a benchmark for developing other scenarios or incorporating real data in order to address the impact of different policies on disclosure and requirement to test. 相似文献
988.
Fevzi Akinci Joseph Coyne Bernard Healey Joni Minear 《Disease Management & Health Outcomes》2004,12(5):285-298
When considering the trends in disease management, the focus of healthcare in the US has shifted from communicable diseases, which can most often be managed successfully, to chronic diseases, which are currently not managed very well. Chronic diseases, such as diabetes mellitus, become a lifelong health problem for the individual, the family, and in the workplace. Currently, there is no vaccine to prevent diabetes and no cure for diabetes once acquired. In order to improve the quality of care for diabetes, national performance measures have been developed to provide a unified set of diabetes-specific performance and outcome measures.The Diabetes Quality Improvement Project (DQIP) founded in 1997 through a partnership between the Center for Medicare and Medicaid Services, the National Committee for Quality Assurance, and the American Diabetes Association, established a single, standardized set of performance measures for diabetes care quality improvement and accountability in the US, which were published in 1998. The DQIP measures are noteworthy as a model for many other chronic diseases. Indeed, the DQIP represents the first widely adopted comprehensive performance measurement standards, not just for diabetes but for any single chronic disease. This is of further significance since it was developed by a coalition of public and private entities in the US.In order to prevent long-term complications from diabetes, there needs to be a physician-coordinated treatment plan involving a team approach to the problem. When such a physician-coordinated treatment plan is developed in conformance with the comprehensive performance measures, the prospects for a greater impact on diabetes might be enhanced.Overall, national performance measures for diabetes care have been widely adopted into health plan quality initiatives and have resulted in increased efforts to promote preventative screening and testing. Better compliance has lead to more stringent glucose control and helped to educate the public on the utility of the glycosylated hemoglobin level test for finding those at risk for microvascular and neuropathic complications. While more Americans with diabetes are receiving the recommended standards of care as a result of the implementation of national performance measures, diabetes management remains suboptimal but achievable.The authors concluded from this review that national performance measures have provided health plans and providers with objective tools to measure quality; however, these measures now need to move to prevention standards and initiatives. Policy development for diabetes care must continue to move from managing chronic illness to preventative screening of pre-diabetes through to identification and modification of lifestyle risk factors. 相似文献
989.
Lee M. Hilliard Mary H. Maddox Shenghui Tang Thomas H. Howard 《Disease Management & Health Outcomes》2004,12(6):393-398
Sickle cell disease (SCD), an inherited group of blood disorders, is a major public health problem worldwide. Patients experience severe anemia, increased risk of life-threatening infections, painful crisis, and chronic organ damage. Access to comprehensive care for SCD is known to improve outcomes; however, it is only reported from large urban centers serving one metropolitan area. Alabama, US, is a largely rural state with a significant number of children born each year with SCD. Prior to the development of our regional clinic network, the Children and Youth Sickle Network (CYSNSM), 50% of patients identified by newborn screening were not enrolled in comprehensive sickle cell care. The majority of non-enrolled patients lived in southern Alabama. Rural areas in this region are particularly plagued by poverty and poor access to healthcare. Life expectancy is equivalent to residents of Sri Lanka. This area has 15.7 doctors/10 000 residents compared with the statewide ratio of 41.9 doctors/10 000 residents.To improve access to care, a regional clinic network, the CYSNSM, was established in 1995. This paper reviews the impact of the CYSNSM on pediatrie SCD in Alabama over the first 5 years of implementation.Since its inception in 1995, the CYSNSM has provided care for 923 patients compared with 450 prior to the development of the clinic network. Currently, 90% of all cases identified by newborn screening are enrolled compared with 50% pre-CYSNSM. Prior to the network, the average age of patients at their first clinic visit was 21 months. In the post-CYSNSM period, the average age at first clinic visit decreased substantially to 5.3 months. Prior to the CYSNSM, patients traveled on average 90 miles to a comprehensive clinic. Post-CYSNSM, this distance has been cut in half to an average of 45 miles. A total of 70% of patients now live within 30 miles of a clinic. Most importantly, the infection death rate has decreased from 5.71 deaths/100 patient years to 1.94 deaths/100 patient years.The development, implementation, and evaluation of the CYSNSM show that comprehensive care delivery in a rural setting is feasible and improves outcomes in pediatric SCD. 相似文献
990.
George A. Mensah Richard A. Goodman Stephanie Zaza Anthony D. Moulton Paula L. Kocher William H. Dietz Terry F. Pechacek James S. Marks 《Preventing chronic disease》2004,1(1)
Law, which is a fundamental element of effective public health policy and practice, played a crucial role in many of public health's greatest achievements of the 20th century. Still, conceptual legal frameworks for the systematic application of law to chronic disease prevention and control have not been fully recognized and used to address public health needs. Development and implementation of legal frameworks could broaden the range of effective public health strategies and provide valuable tools for the public health workforce, especially for state and local health department program managers and state and national policy makers. In an effort to expand the range of effective public health interventions, the Centers for Disease Control and Prevention will work with its partners to explore the development of systematic legal frameworks as a tool for preventing chronic diseases and addressing the growing epidemic of obesity, heart disease, stroke, and other chronic diseases and their risk factors. 相似文献