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The purpose of this article is to describe the extent to which certified nurse-midwives (CNMs) provide care to vulnerable populations in the United States and the source of reimbursement for this care. The data were obtained from the first phase of a national study to address the characteristics of women served and cost of care provided by CNMs. Results were analyzed nationally and by American College of Nurse-Midwives regions. Certified nurse-midwives in all types of practices are providing care to women from populations that are vulnerable to poorer than average outcomes of childbirth because of age, socioeconomic status, refugee status, and ethnicity. Ninety-nine percent of CNMs report serving at least one group of vulnerable women, and CNMs in the inner city and rural practices serve several groups. The vast majority of CNMs are salaried; only 11% receive their primary income from fee-for-service. Fifty percent of the payment for CNM services is from Medicaid and government-subsidized sources whereas less than 20% comes from private insurance. Source of income varies by type of setting in which the CNM attends births. The results suggest that CNMs, as a group, make a major contribution to the care of vulnerable populations.  相似文献   
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1. The rotation-mediated three-dimensional reaggregate culture system is uniquely suited for studies on developmental neurotoxicity. In this system, it is possible to reconstruct central neuronal pathways and follow their development. 2. Exposure to drugs of abuse including methamphetamine and methylenedioxyamphetamine or the appetite suppressant, fenfluramine, reduces monoamines in the cultures in a dose-dependent manner and interrupts normal monoaminergic development. 3. While the monoaminergic neurones may attain normal rates of development following drug removal, the affected neurones are not capable of overcoming the drug-induced insults and a deficiency in monoamines persists throughout development. 4. In addition, the production of immortalized monoclonal hybrid cells obtained by fusion of fetal mesencephalic neurones with a neuroblastoma has yielded cell lines expressing a dopaminergic phenotype. 5. Such cells have been useful in establishing the relationship of neurotoxicity to cell lineage and can serve as models for the study of the cellular and molecular mechanisms of neurotoxicity.  相似文献   
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Portion Sizes in Dietary Assessment: Issues and Policy Implications   总被引:5,自引:0,他引:5  
Accurate estimates of energy and nutrient intake of individuals and populations are contingent on the reliability of information obtained about food intake, food composition, and portion size. This article reviews issues related to the definition, determination, and use of portion sizes in dietary assessment and public education.  相似文献   
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Metastasis (the spread of cancer from a primary tumor to secondary organs) is responsible for most cancer deaths. The ability to follow the fate of a population of tumor cells over time in an experimental animal would provide a powerful new way to monitor the metastatic process. Here we describe a magnetic resonance imaging (MRI) technique that permits the tracking of breast cancer cells in a mouse model of brain metastasis at the single-cell level. Cancer cells that were injected into the left ventricle of the mouse heart and then delivered to the brain were detectable on MR images. This allowed the visualization of the initial delivery and distribution of cells, as well as the growth of tumors from a subset of these cells within the whole intact brain volume. The ability to follow the metastatic process from the single-cell stage through metastatic growth, and to quantify and monitor the presence of solitary undivided cells will facilitate progress in understanding the mechanisms of brain metastasis and tumor dormancy, and the development of therapeutics to treat this disease.  相似文献   
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OBJECTIVE: We investigated the heat stability of six common therapeutic drugs routinely assayed in pharmacokinetic and clinical laboratories. DESIGN: Serum samples were spiked at three concentrations (subtherapeutic, therapeutic, and potentially toxic) with amikacin, gentamicin, tobramycin, phenytoin, theophylline, and phenobarbital. The samples were then heated at 56 degrees C and assayed by fluorescence polarization immunoassay at 15-minute intervals for one hour. SETTING: The study was conducted at a clinical research laboratory using standard laboratory methods. MAIN OUTCOME MEASURES: Drug concentrations of heated samples were compared with unheated controls using ANOVA to determine if degradation occurred over time with heating. RESULTS: Analysis of data revealed no degradation of any of the samples. CONCLUSIONS: Heat treatment of samples from high-risk individuals may be a mechanism to protect healthcare workers from exposure to the human immunodeficiency virus.  相似文献   
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The Multiphasic Environmental Assessment Procedure (MEAP; Moos and Lemke, 1984) was used to assess three long-stay settings within a geriatric hospital, one of which is a non-nursing unit committed to the philosophy of residents viewing the setting as their own home. Findings suggest positive outcomes for residents on the nonnursing unit, and support the view that types of care fostering independence and personal responsibility of elderly residents in their setting may be associated with increased mental functioning and activity. The lack of trained nursing staff had no detrimental effect on any measure of resident life, and some specific caring practices on the unit may be interpreted as having a positive outcome for residents.  相似文献   
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