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Juvenile hypocalcemia provokes persistent electroencephalographic change in renally compromised rats
J J Lipman D L White P L Lawrence P E Teschan 《Journal of the American College of Nutrition》1988,7(6):453-460
In view of the putative involvement of calcium in uremic encephalopathy and the critical importance of this element in juvenile development, we examined the effect of temporary restriction of dietary calcium intake on serum chemistry and the quantitative electroencephalogram (Q.EEG) in unilaterally 3/4 nephrectomized juvenile male Sprague-Dawley rats. Animals were renally infarcted at 22-26 days of age (50-74 g) and placed on one of two isocaloric dietary regimens: powdered normal rat diet (ND, n = 25) or low calcium diet (LCD, n = 8) for 30 days. At this time, ND animals showed normal serum chemistries, whereas LCD rats were hypocalcemic and azotemic with significantly elevated blood urea nitrogen (BUN) and serum creatinine concentrations and reduced renal creatinine clearance values. All animals thereafter received ND for 25-34 further days, during which time chronic Q.EEG electrodes were implanted. At the end of the common ND feeding period, serum chemistry values were equal and normal in both groups. The average theta/alpha ratio (TAR) of the overnight Q.EEG was assessed for 3 days. We found that the TAR of previously LCD animals was significantly elevated compared with ND rats. This indicates an encephalopathic slowing of the background rhythm of these animals. We conclude that, following restoration of a transient uremic and hypocalcemic episode induced by LCD feeding, the Q.EEG background frequency of juvenile renally impaired rats was abnormally slow after 30 days of ND feeding. 相似文献
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Studies of clinical populations suggest that adopted children are overrepresented among children using mental health facilities, whereas studies using non clinical populations of adopted children have reached mixed conclusions about whether or not there is an increased psychological risk associated with adoption. Data from the Ontario Child Health Study, a community survey of children aged four to 16 years, which included a subpopulation of adopted children, were used to: 1. profile the characteristics of adoptive families; 2. examine the strength of adoptive status as a marker for psychiatric and educational morbidity; and 3. determine the extent to which adoptive status has an independent relationship with psychiatric and educational morbidities. The findings were: 1. adoptive mothers were significantly older than non adoptive mothers, but otherwise adoptive families did not differ significantly from non adoptive families, 2. adoption in boys, but not in girls, was a significant marker for psychiatric disorder and poor school performance; adoption in adolescent girls was a significant marker for substance use; and 3. multivariate analyses demonstrated no independent effect of adoption on psychiatric disorder or poor school performance; for adolescents, adoptive status did have an independent relationship with substance use for girls. The implications of these findings will be discussed. 相似文献
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Coon DW Lipman PD Ory MG 《Journal of acquired immune deficiency syndromes (1999)》2003,33(Z2):S194-S205
Social and behavioral HIV/AIDS prevention interventions designed to test their effects on older cohorts are sorely lacking in the scientific literature even though middle-aged and older people represent a significant minority of both existing and new AIDS cases. This article raises key issues relevant in developing and evaluating HIV/AIDS social and behavioral interventions for older cohorts. These interventions must build on our current understanding of behavior change and HIV prevention successes with younger populations while considering important intervention principles gathered from work with older populations in other health arenas. In addition, the authors expand on recent national panels and published reviews relevant to the topic and provide a set of intervention recommendations for use in tandem with these intervention principles. The article also calls for additional research into the sociocultural contexts that influence risk-taking among older cohorts and for the development of interventions at multiple levels. Pragmatic considerations such as identifying and dismantling ageism in interventions, delineating intervention outcomes, and planning for intervention transferability, dissemination, and sustainability also are raised. 相似文献
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Lipman TO 《Current opinion in clinical nutrition and metabolic care》1999,2(5):387-393
Home artificial nutrition is a mature technology that has been with us for over a quarter of a century. Its use appears to be more widespread in the USA than in other western countries. Issues of outcome, ethics, and quality of life are increasingly important. Complications continue to be reported, some newly recognized and some that we must continually relearn. 相似文献
10.
A community outbreak of Legionnaires' disease linked to hospital cooling towers: an epidemiological method to calculate dose of exposure. 总被引:1,自引:0,他引:1
C M Brown P J Nuorti R F Breiman A L Hathcock B S Fields H B Lipman G C Llewellyn J Hofmann M Cetron 《International journal of epidemiology》1999,28(2):353-359
BACKGROUND: From July to September 1994, 29 cases of community-acquired Legionnaires' disease (LD) were reported in Delaware. The authors conducted an investigation to a) identify the source of the outbreak and risk factors for developing Legionella pneumophila serogroup 1 (Lp-1) pneumonia and b) evaluate the risk associated with the components of cumulative exposure to the source (i.e. distance from the source, frequency of exposure, and duration of exposure). METHODS: A case-control study matched 21 patients to three controls per case by known risk factors for acquiring LD. Controls were selected from patients who attended the same clinic as the respective case-patients. Water samples taken at the hospital, from eight nearby cooling towers, and from four of the patient's homes were cultured for Legionella. Isolates were subtyped using monoclonal antibody (Mab) analysis and arbitrarily primed polymerase chain reaction (AP-PCR). RESULTS: Eleven (52%) of 21 case-patients worked at or visited the hospital compared with 17 (27%) of 63 controls (OR 5.0, 95% CI : 1.1-29). For those who lived, worked, or visited within 4 square miles of the hospital, the risk of illness decreased by 20% for each 0.10 mile from the hospital; it increased by 80% for each visit to the hospital; and it increased by 8% for each hour spent within 0.125 miles of the hospital. Lp-1 was isolated from three patients and both hospital cooling towers. Based on laboratory results no other samples contained Lp-1. The clinical and main-tower isolates all demonstrated Mab pattern 1,2,5,6. AP-PCR matched the main-tower samples with those from two case-patients. CONCLUSION: The results of our investigation suggested that the hospital cooling towers were the source of a community outbreak of LD. Increasing proximity to and frequency of exposure to the towers increased the risk of LD. New guidelines for cooling tower maintenance are needed. Knowing the location of cooling towers could facilitate maintenance inspections and outbreak investigations. 相似文献