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31.
To investigate the in vivo role of NMDA receptor stimulation in HIV-1-related CNS neurotoxicity, we evaluated the neuroprotective potential of the NMDA receptor antagonist memantine in transgenic mice which have gp120-induced CNS damage. Brains of mice treated chronically with memantine and of untreated controls were analysed for structural damage by laser scanning confocal microscopy of sections immunolabeled for microtubule-associated protein-2 (MAP-2) and synaptophysin. Qualitative and quantitative analysis of confocal images revealed that memantine treatment substantially decreased neuropathology in gp120 transgenic mice; this included statistically significant improvements in both dendritic and presynaptic terminal density. These results provide in vivo evidence that gp120 can activate neurotoxic pathways that can ultimately result in aberrant NMDA receptor stimulation and neuronal damage in the CNS. They also suggest that clinically tolerated NMDA receptor antagonists may be useful in the prevention of neuronal damage in HIV-1-infected patients.  相似文献   
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The yeast spectrum of the 'tea fungus Kombucha'   总被引:1,自引:0,他引:1  
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ABSTRACT: Managed care organizations (MCOs) joined local and state public health agencies in a pilot effort to improve hepatitis B immunization rates of adolescents in an urban and a suburban/rural school district. The pilot also explored issues inherent in public and private collaboration on population health improvement.
Local public health agencies provided links to schools in their communities, took the lead in implementing school-based immunization programs, and provided health education materials. MCOs contributed financial support necessary for the project. The final cost per fully vaccinated student, not taking into account the work group's planning and coordination time, was little more than the catalog price of the vaccine alone.
Managed care organizations face challenges that complicate their participation and funding of school-based vaccinations: 1) Limited data on health plans of participating students complicate allocation of costs to each MCO; 2) Double-paying occurs for MCOs paying clinics a monthly, per-member rate that already includes adolescent immunizations; 3) When schools provide adolescent immunizations, MCOs lose the "hook" that draws adolescents to clinics for comprehensive health services.
When self-consenting is permitted, schools can achieve a high consent and completion rates for multi-dose adolescent immunizations such as hepatitis B. At the same time, MCOs have the responsibility to provide members with comprehensive care and should continue to examine both internal modifications and external partnerships as opportunities to improve their services to adolescents.  相似文献   
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The value of positron emission tomography using [18F]-fluoro-deoxy-glucose (FDG-PET) for pretherapeutic evaluation of patients with non-small cell lung cancer (NSCLC) is beyond doubt. Due to the increasing availability of PET and PET-CT scanners the method is now widely available, and its technical integration has become possible for radiotherapy planning systems. Due to the depiction of malignant tissue with high diagnostic accuracy, the use of FDG-PET in radiotherapy planning of NSCLC is very promising. However, by uncritical application, PET could impair rather than improve the prognosis of patients. Therefore, in the present paper we give an overview of technical factors influencing PET and PET-CT data, and their consequences for radiotherapy planning. We further review the relevant literature concerning the diagnostic value of FDG-PET and on the integration of FDG-PET data in RT planning for NSCLC. We point out the possible impact in gross tumor volume (GTV) definition and describe methods of target volume contouring of the primary tumor, as well as concepts for the integration of diagnostic information on lymph node involvement into the clinical target volume (CTV), and the possible implications of PET data on the definition of the planning target volume (PTV). Finally, we give an idea of the possible future use of tracers other than [18F]-FDG in lung cancer.  相似文献   
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Fashion parades, balls, raffles, and weekly deductions from thousands of workers' pay packets were integral to success of the Cancer Appeal-a-thon in the Illawarra region. In 1986–87 the Illawarra community was induced to contribute $1.5 million in order to purchase a linear accelerator for the Wollongong Hospital. The community agreed that a radiotherapy machine was the number one health service priority for the region. Or did it? Application of Alford's structural interests framework to this case-study reveals how failure to examine power relations between medical monopolizers, health care rationalizers and community participants results in an inability to recognise that alternative community needs — for cancer prevention, domiciliary care, or alternative therapies — might be unarticulated or unobservable, and in an inability to ask whether the community may be mistaken about, or unaware of, its own health needs. Specifically, the paper argues that, ‘community needs’ are easily manipulated or distorted by powerful interest groups and that the political context within which community needs are recognized, articulated and mobilized is the most important issue for community participation in the health policy-making process.  相似文献   
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This is a double-blind placebo-controlled study of sustained-release bupropion as a smoking cessation aid in alcoholics undergoing treatment for their alcoholism. Participants (N=58) were enrolled within 1 week of entry into alcohol treatment from community and Veterans Affairs Substance Use Disorder programs. All participants received nicotine patch and were invited to attend a smoking cessation lecture and group. Cigarette smoking and alcohol outcomes were measured at 6 months. Bupropion when added to nicotine patch did not improve smoking outcomes. One third of participants on bupropion reported discontinuing the drug during weeks 1-4. Participants reported cigarette outcomes with nicotine patch that are similar to those seen in the general population. All study participants significantly reduced cigarette use. Comorbid affective disorder or antipersonality disorder did not affect outcomes. Alcohol outcomes were improved in those who discontinued cigarettes.  相似文献   
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