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31.
Brener ND Wheeler L Wolfe LC Vernon-Smiley M Caldart-Olson L 《The Journal of school health》2007,77(8):464-485
Background: The specific health services provided to students at school and the model for delivering these services vary across districts and schools. This article describes the characteristics of school health services in the United States, including state‐ and district‐level policies and school practices. Methods: The Centers for Disease Control and Prevention conducts the School Health Policies and Programs Study (SHPPS) every 6 years. In 2006, computer‐assisted telephone interviews or self‐administered mail questionnaires were completed by state education agency personnel in all 50 states plus the District of Columbia and among a nationally representative sample of school districts (n = 449). Computer‐assisted personal interviews were conducted with personnel in a nationally representative sample of elementary, middle, and high schools (n = 1029). Results: Most US schools provided basic health services to students, but relatively few provided prevention services or more specialized health services. Although state‐ and district‐level policies requiring school nurses or specifying maximum nurse‐to‐student ratios were relatively rare, 86.3% of schools had at least a part‐time school nurse, and 52.4% of these schools, or 45.1% of all schools, had a nurse‐to‐student ratio of at least 1:750. Conclusions: SHPPS 2006 suggests that the breadth of school health services can and should be improved, but school districts need policy, legislative, and fiscal support to make this happen. Increasing the percentage of schools with sufficient school nurses is a critical step toward enabling schools to provide more services, but schools also need to enhance collaboration and linkages with community resources if schools are to be able to meet both the health and academic needs of students. 相似文献
32.
Yiannoutsos CT Ernst T Chang L Lee PL Richards T Marra CM Meyerhoff DJ Jarvik JG Kolson D Schifitto G Ellis RJ Swindells S Simpson DM Miller EN Gonzalez RG Navia BA 《NeuroImage》2004,23(3):928-935
The relationship of the cellular changes in the HIV-infected brain to the onset and progression of AIDS dementia complex (ADC) remains uncertain. We undertook an in vivo proton magnetic resonance spectroscopy (MRS) study and used factor analysis to identify specific cellular and regional brain changes that may serve as metabolic markers of ADC. The ratio of N-acetyl aspartate (NAA), choline (Cho), and myoinositol (MI) over creatine (Cr), markers of neuronal and glial cell metabolism, were measured in the basal ganglia, centrum semiovale, and parietal cortex from 100 subjects with and without ADC. Three metabolic patterns were identified, which we termed "inflammatory" (mainly MI/Cr elevations in all three regions plus Cho/Cr increases in the centrum semiovale and parietal cortex), "basal ganglia" (mostly NAA/Cr and Cho/Cr elevations in the basal ganglia), and "neuronal" (primarily NAA/Cr reductions in the centrum semiovale and the parietal cortex). Logistic regression analysis revealed that, adjusted for age, basal ganglia and neuronal pattern scores were strongly associated with ADC but inflammatory levels were not. We conclude that by using factor analysis, we are able to combine multiple metabolites across brain regions in a biologically plausible manner and construct a predictive model of ADC adjusting for relevant factors such as age. 相似文献
33.
Dramé M Lang PO Jolly D Narbey D Mahmoudi R Lanièce I Somme D Gauvain JB Heitz D Voisin T de Wazières B Gonthier R Ankri J Saint-Jean O Jeandel C Couturier P Blanchard F Novella JL 《Journal of the American Medical Directors Association》2012,13(1):83.e17-83.e20
ObjectivesThe aim of this study was to identify factors predictive of nursing home admission (NHA) over a period of 1 year among elderly subjects with dementia.MethodsThe study population was drawn from the SAFES cohort that was formed within a national research program into the recruitment of emergency departments in 9 teaching hospitals. Subjects were to have been hospitalized in a medical ward in the same hospital as the emergency department to which they were initially admitted. Subjects who experienced NHA before emergency department admission were excluded. Those with a confirmed diagnosis of dementia were considered in the present analysis. NHA has been defined as the incident admission into either a nursing home or other long term care facility within the follow-up period. Data obtained from a Comprehensive Geriatric Assessment were used in a Cox model to predict 1-year NHA.ResultsThe 425 subjects of the study were 86 ± 6 years old, and were mainly women (63%). NHA rate was 40% (n = 172). Four factors were identified to increase NHA risk: age 85 or older (hazard ratio [HR] = 1.5; 95% confidence interval [CI] = 1.1–2.1), inability to use the toilet (HR = 2.5; 95% CI = 1.5–4.2), balance disorders (HR = 1.5; 95% CI = 1.1–2.1), and living alone (HR = 1.5; 95% CI = 1.1–2.1). Three factors decreased this risk significantly: inability to transfer (HR = 0.5; 95% CI = 0.3–0.8), increased number of children (HR = 0.88; 95% CI = 0.96–0.99), and increased initial Mini-Mental State Examination score (HR = 0.97; 95% CI = 0.8–0.9).ConclusionNHA determinants in dementia are strongly linked to the patient’s own characteristics but also to his or her physical or social environment. Interventions should target both members of the dyad “patient-caregiver” because both are affected by the disease. 相似文献
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35.
Ester C. Sabino Tzong‐Hae Lee Lani Montalvo Megan L. Nguyen David A. Leiby Danielle M. Carrick Marcia M. Otani Elizabeth Vinelli David Wright Susan L. Stramer Michael Busch NHLBI Retrovirus Epidemiology Donor Study‐II International Program 《Transfusion》2013,53(6):1257-1265
BACKGROUND: The clinical significance of anti‐Trypanosoma cruzi low‐level reactive samples is incompletely understood. Polymerase chain reaction (PCR)‐positive rates and antibody levels among seropositive blood donors in three countries are described. STUDY DESIGN AND METHODS: Follow‐up samples were collected from T. cruzi–seropositive donors from 2008 through 2010 in the United States (n = 195) and Honduras (n = 58). Also 143 samples from Brazil in 1996 to 2002, originally positive by three serologic assays, were available and paired with contemporary follow‐up samples from these donors. All samples were retested with Ortho enzyme‐linked immunosorbent assay (ELISA). PCR assays were performed on coded sample panels by two laboratories (Blood Systems Research Institute [BSRI] and American Red Cross Holland Laboratory [ARC]) that amplified kinetoplast minicircle DNA sequences of T. cruzi. RESULTS: PCR testing at BSRI yielded slightly higher overall sensitivity and specificity (33 and 98%) compared with those at the ARC (28 and 94%). Among seropositive donors, PCR‐positive rates varied by country (p < 0.0001) for the BSRI laboratory: Brazil (57%), Honduras (32%), and the United States (14%). ELISA signal‐to‐cutoff ratios (S/CO) were significantly higher for PCR‐positive compared to PCR‐negative donors (p < 0.05 for all comparisons). Additionally, PCR‐negative Brazilian donors exhibited greater frequencies of antibody decline over time versus PCR‐positive donors (p = 0.003). CONCLUSION: For all three countries, persistent DNA positivity correlated with higher ELISA S/CO values, suggesting that high‐level seroreactivity reflects chronic parasitemia. Significant S/CO declines in 10% of the PCR‐negative Brazilian donors may indicate seroreversion after parasite clearance in the absence of treatment. 相似文献
36.
Arterial input function measurement without blood sampling using a beta-microprobe in rats. 总被引:1,自引:0,他引:1
Frédéric Pain Philippe Lanièce Roland Mastrippolito Philippe Gervais Philippe Hantraye Laurent Besret 《Journal of nuclear medicine》2004,45(9):1577-1582
The evaluation of every new radiotracer involves pharmacokinetic studies on small animals to determine its biodistribution and local kinetics. To extract relevant biochemical information, time-activity curves for the regions of interest are mathematically modeled on the basis of compartmental models that require knowledge of the time course of the tracer concentration in plasma. Such a time-activity curve, usually termed input function, is determined in small animals by repeated blood sampling and subsequent counting in a well counter. The aim of the present work was to propose an alternative to blood sampling in small animals, since this procedure is labor intensive, exposes the staff to radiation, and leads to an important loss of blood, which affects hematologic parameters. METHODS: Monte Carlo simulations were performed to evaluate the feasibility of measuring the arterial input function using a positron-sensitive microprobe placed in the femoral artery of a rat. The simulation results showed that a second probe inserted above the artery was necessary to allow proper subtraction of the background signal arising from tracer accumulation in surrounding tissues. This approach was then validated in vivo in 5 anesthetized rats. In a second set of experiments, on 3 rats, a third probe was used to simultaneously determine 18F-FDG accumulation in the striatum. RESULTS: The high temporal resolution of the technique allowed accurate determination of the input function peak after bolus injection of 18F-FDG. Quantitative input functions were obtained after normalization of the arterial time-activity curve for a late blood sample. In the second set of experiments, compartmental modeling was achieved using either the blood samples or the microprobe data as the input function, and similar kinetic constants were found in both cases. CONCLUSION: Although direct quantification proved difficult, the microprobe allowed accurate measurement of arterial input function with a high temporal resolution and no blood loss. The technique, because offering adequate sensitivity and temporal resolution for kinetic measurements of radiotracers in the blood compartment, should facilitate quantitative modeling for radiotracer studies in small animals. 相似文献
37.
Zusammenfassung Bei drei ALS-behandelten Patienten mit chronischer Lymphadenose wurden die zirkulierenden Lymphozyten vor und während der ALS-Gabe sowie nach Inkubation mit ALS elektronenmikroskopisch untersucht. Die Lymphozyten zeigten während der Behandlung weder qualitative noch quantitative (Einteilung in 4 Gruppen, Ausdifferenzierung) Veränderungen. An den ALS-inkubierten Lymphozyten waren verschiedenartige Schäden nachzuweisen, die mit entsprechenden Befunden anderer Untersucher verglichen werden.
Summary Lymphocytes of three patients suffering from chronic lymphocytic leukemia were studied electromicroscopically before and during ALS-treatment and after in-vitro-incubation with ALS. During the treatment, no qualitative or quantitative changes were shown. After incubation with ALS different changes could be demonstrated. The findings are discussed.相似文献
38.
Cheryl Schwartz Ronald L. Morgan Lani M. Way James L. Way 《Toxicology and applied pharmacology》1979,50(3):437-441
Cyanide intoxication in mice can be effectively antagonized by sodium pyruvate, particularly if it is administered in combination with the antidotes, sodium nitrite and sodium thiosulfate. Potency ratios derived from the LD50 data were compared in groups of mice treated with sodium nitrite, sodium thiosulfate, and sodium pyruvate either alone or in various combinations. These results indicate that the administration of sodium pyruvate alone does provide minimal, but statistically significant, protection against the lethal effects of cyanide. Sodium pyruvate does not enhance the effect of sodium nitrite; however, it does potentiate the antidotal effect of sodium thiosulfate. The sodium thiosulfate and sodium pyruvate combination is not as effective as the sodium nitrite and sodium thiosulfate combination, but the addition of sodium pyruvate to the sodium nitrite-sodium thiosulfate combination further enhances the antidotal effect. No further enhancement is observed when sodium nitrite, sodium thiosulfate, and sodium pyruvate are combined with oxygen. 相似文献
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