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81.
Air pollution and infant mortality in Mexico City   总被引:9,自引:0,他引:9  
Historic air pollution episodes of the 1950s led to acute increases in infant mortality, and some recent epidemiologic studies suggest that infant or child mortality may still result from air pollution at current levels. To investigate the evidence for such an association, we conducted a time-series study of infant mortality in the southwestern part of Mexico City in the years 1993 to 1995 using mortality data from death registrations and air pollution measurements from a monitoring station we operated. Excess infant mortality was associated with the level of fine particles in the days before death, with the strongest association observed for the average concentration of fine particles during the period 3 to 5 days previously: a 10-microg m(-3) increase in the mean level of fine particles during these 3 days was associated with a 6.9% excess of infant deaths (95% confidence interval 2.5-11.3%). Infant mortality was also associated with the levels of nitrogen dioxide and ozone 3 to 5 days before death, but not as consistently as with particles.  相似文献   
82.
States have moved swiftly to start materializing the Children's Health Insurance Program (CHIP). The program enacted in 1997 hopes to cover millions of uninsured American children targeting children up to age 19 in families with incomes 200% below the federal poverty line. All 50 states and the District of Columbia have secured federal approval for the program whose coverage includes family planning services and supplies for enrolled adolescents. Their plans gave the program an enormous potential to help meet the reproductive health care needs of 2.7 million uninsured teenagers. However, with the low number of individuals enrolled than expected, the federal and state governments, initiated efforts to develop more extensive and aggressive outreach activities to boost CHIP enrollment.  相似文献   
83.
OBJECTIVE: To utilize health services research techniques in developing an episode of care using an administrative data set. This method is demonstrated for an episodic clinical condition, migraine. DATA SOURCES: Medicaid administrative data set of 3,372 patients with a diagnosis of migraine (ICD-9-CM 346.0, 346.1) in the state of Pennsylvania between May 1990 and March 1992. STUDY DESIGN: The duration of a migraine episode was measured by assessing the magnitude of resource utilization and the proportion of patients with charges in the period after the index migraine as compared to the period before the index migraine. A confidence interval (CI) was developed around each measure using bootstrap techniques. DATA COLLECTION METHODS: All charge data were extracted daily for a 113-day observation period surrounding each index migraine in order to observe the duration of impact of a migraine diagnosis on resource utilization. PRINCIPAL FINDINGS: The lower limits of both the 95% and 99% CIs for the difference in charges are greater than 0 for three weeks. The lower limits of both CIs for the difference in the proportion of patients with charges are above 0 for six weeks. CONCLUSIONS: Our analysis demonstrates that a health services research framework can be used to define an episode of care for a chronic disease category such as migraine. This method can be used to evaluate episodes of care for clinical studies of limited or episodic conditions and to complement clinical expertise in developing time horizons for clinical trials.  相似文献   
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85.
BACKGROUND: Opioid addiction therapy includes successful detoxification, rehabilitation, and sometimes methadone maintenance. However, the patient may have physical, mental, and emotional pain while trying to achieve abstinence. A new detoxification technique that incorporates general anesthesia uses a high-dose opioid antagonist to compress detoxification to within 6 h while avoiding the withdrawal. METHODS: After Institutional Review Board approval and detailed informed consent, 20 patients, American Society of Anesthesiologists status I-II, addicted to various opioids underwent anesthesia-assisted rapid opioid detoxification. After baseline hemodynamics and withdrawal scores were obtained, anesthesia was induced. After testing with 0.4 mg intravenous naloxone, 4 mg nalmefene, was infused over 2 to 3 h. After emergence, severity of withdrawal was scored before and after administration of 0.4 mg intravenous naloxone. After 24 h, patients began outpatient follow-up treatment while taking oral naltrexone. RESULTS: All 20 patients were successfully detoxified with no adverse anesthetic events. After the first post-treatment test dose of 0.4 mg naloxone, 13 of 20 patients had no signs of withdrawal and hemodynamic changes were minimal. Withdrawal scores were always very low and similar before and after detoxification. Three of 17 patients (18%) available for follow-up have remained abstinent from opioids since treatment (< or = 18 months). Four other patients are clean after brief relapses. CONCLUSIONS: Anesthesia-assisted opioid detoxification is an alternative to conventional detoxification.  相似文献   
86.
In EAN, TCR variable (V) gene usage is still controversial. A dominant usage of a TCR Vbeta4-associated idiotype has been reported. To assess the role of TCR Vbeta4 positive T-cells in susceptibility to induction of EAN, we suppressed the selection of this idiotype by neonatal treatment of Lewis rats with anti-TCR Vbeta4 monoclonal antibody (mAb). Anti-Vbeta4 treatment had no effect on development of clinical disease after immunization with the neuritogenic P2-peptide amino acids (aa) 53-78. Furthermore, lymph node cells from anti-Vbeta4 treated animals isolated after immunization with P2-peptide did not exhibit a reduced proliferative response towards whole P2-protein or P2-peptide. Our results indicate that T-cells utilizing other TCR V chains can functionally replace the neuritogenic cell population, which is dominant in stable T-cell lines.  相似文献   
87.
What drives Medicare managed care growth?   总被引:2,自引:0,他引:2  
We conducted case studies of four markets--Los Angeles, New York City, Portland (OR), and Tampa-St. Petersburg--to learn more about why Medicare managed care develops differently across the country even when capitation rates are similar. Our analysis highlights the importance of prior managed care history, beneficiary characteristics, supplemental coverage patterns, the form of provider organization, practice patterns, care expectations, and other market characteristics to the development of Medicare managed care. Policymakers seeking to expand Medicare managed care need to go beyond national statistics to understand how local market forces affect its growth.  相似文献   
88.
This research compared how over a three-month period Canadian and Israeli newspapers wrote about females and males with disabilities. The results showed that in both countries there was significantly greater coverage of males than females. In addition, different (and stereotypical) types of details were used to describe the two groups, and females were associated with different kinds of problems than males, including a higher incidence of violence and victimization. There were also some significant differences between the male and female journalists in this study, and evidence of sexism within the newspaper industry. This paper concludes with some ideas for altering the images of disabled women in the media.  相似文献   
89.
The "managed care backlash" arguably topped the list of media and policy concerns in 1998. Yet, against the background of the highly charged environment in which the future of our health care system continues to be debated, there is a dearth of concrete, "objective" facts on the nature of the changes, the reasons for them, and their meaning. An analysis of five important themes that emerged from a review of the recent literature on health system change concludes that an inherent tension exists between the interest in rapidly driving down health care costs through organizational change and the long time frames that are required to make fundamental changes in structure, process, and orientation. Unfortunately, in an environment in which purchasers are driven to seek cost savings and the political will supports a pluralistic and mixed public/private system, the health system may chart an alternative course, with the result that purchasers may rely increasingly on individual cost sharing and continue to cut back the amount of coverage they are willing to offer. The real challenge for public policy makers is to confront the issues directly, avoiding political incentives to adopt easy and fast solutions for these complex matters.  相似文献   
90.
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