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Little research attention has focused on ways to encourage physician response to prenatal substance exposure. We report initial results from a study examining the impact of state laws and work-place policies on physician response by combining legal analyses and data from a national physician survey. Our findings indicate that the message that laws and policies exist usually does not reach physicians. However, when the message does come through, some physician behaviors are influenced. In particular, physicians in states with clearer policies and behavioral expectations are significantly more likely to know and understand the law than physicians in other states. Further, believing that a work-place protocol on prenatal substance exposure exists is associated with significantly increased likelihood of an active response in case vignettes portraying prenatal substance exposure. The findings suggest that state legislative behaviors may increase physician response to prenatal substance exposure, but that response depends on the nature of the policy and on efforts to disseminate it.  相似文献   
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Objective To assess the accuracy of several published equations for predicting basal metabolic rate (BMR) in older women.

Design BMR was assessed in 116 healthy, older white women, aged 60 to 82 years, on three successive mornings by indirect calorimetry. Body composition was determined by dual energy X-ray absorptiometry or hydrostatic weighing. The measured BMRs were compared with values obtained from eight published prediction equations that used solely, or in various combinations, measures of height, weight, fat-free mass, age, and menopausal status.

Statistical analyses performed The root mean squared prediction error (RMSPE) was used to determine how accurately predicted BMR matched actual BMR for each subject. In addition, regression analysis was used to evaluate accuracy of predicted BMR vs directly measured BMR.

Results Predicted mean BMR determined using all eight equations was significantly correlated to measured BMR (P=.0001), accounting for 30% to 52% of the variance of measured BMR. When analyzed by RMSPE, however, the equations of Owen et al (1986), Fredrix et al (1990), and Harris-Benedict (1919) predicted actual BMR for each subject within an average of 116 kcal/day, and the equation of Cunningham (1980) resulted in the largest prediction error at 208 kcal/day.

Applications/conclusions The regression equations of Owen et al (1986), which used body weight, Fredrix et al (1990), which used body weight and age, and Harris-Benedict (1919), which used age, weight, and height as variables, were most accurate in predicting BMR in our sample of healthy older women. J Am Diet Assoc. 1995; 95:1387-1392.  相似文献   

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Preclinical Toxicology Studies with Acyclovir: Genetic Toxicity Tests   总被引:2,自引:0,他引:2  
Preclinical Toxicology Studies with Acyclovir: Genetic ToxicityTests. Clive, D., Turner, N.T., Hozier, J., Batson, A.G. andTucker, W.E., Jr. (1983). Fundam. Appl. Toxicol 3: 587–602.Acyclovir (ACV), an antiviral drug active in the treatment oforal and genital Herpes infections, has been evaluated for mutagenicand carcinogenic potential in a battery of in vitro and in vivoshort-termassays. Negative results were obtained in the following in vitrotests: Ames Salmonella, plate incorporation and preincubationmodification assays; E. coli polA+/polA DNA repair; yeast(S. cerevisiae D4) gene conversion; Chinese hamster ovary cells(HGPRT, APRT loci and ouabain-resistance marker); L5178 Y mouselymphoma cells (HGPRT locus and ouabain-resistance marker);and C3H/10Tmouse fibroblast neo-plastic transformation assay.All except the last assay were performed in the presence andabsence of an exogenous metabolic activation system. ACV waspositive at high concentrations x exposure times in the absenceof exogenous metabolic activation in the following in vitrosystems and at the indicated concentrations: BALB/c-3T3 neoplastictransformation (50 /µg/mL, 72 h exposure); human lymphocytecytogenetics (250–500 µg/mL, 48 h exposure); andL5178Y mouse lymphoma cells (TK locus, 400–2400 µg/mL,4 h exposure; predominantly small colony mutants of chromosomalorigin produced). No effects were seen in vivo (mouse dominantlethal assay; rat and Chinese hamster bone marrow cytogenetics)at up to maximum tolerated doses (MTD). An unusual clastogeniceffect was seen in Chinese hamsters at 5 times the MTD. Overall,positive effects were seen only at either high concentrations(250 µg/mL in vitro or plasma levels) or prolonged exposure(72 hr in the BALB/ c-3T3 neoplastic transformation assay).These studies support the view that ACV is a chromosomal mutagen,i.e., one which causes multi-locus damage but not single geneeffects. The significance of these results for the genetic riskof ACV to man is discussed.  相似文献   
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While researchers have examined the established the foundation for understanding the correlates of complementary and alternative medicine (CAM) use among some medical populations, less is known about the correlates of CAM use in nonclinical samples of women, and particularly according to sexual orientation. Information on CAM modalities was collected as part of a survey of lesbian and heterosexual women's health. Eighty-two percent of the sample reported CAM use. Predictors of CAM use included a lesbian sexual orientation, less health-related worry, and perceived discrimination in health care settings. Additional research is warranted to better understand how sexual orientation relates to use of CAM. Future studies should also examine the relationships between and experiences with discrimination in traditional medical settings and increased use of complementary and alternative medicine.  相似文献   
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Our experience with two genetically confirmed cases of late onset Huntington's disease (HD) in a longitudinal dementia research study suggested that clinical misdiagnosis can easily occur. We therefore undertook genetic testing for HD in a further 84 elderly subjects, 81 of whom had come to postmortem; 75 subjects had dementia and nine were normal controls. A quarter of the demented group had demonstrated extrapyramidal symptoms in life but in none had HD formed part of the differential diagnosis. Although no genetically confirmed cases were found in this second group, the original cases serve as a reminder that late onset HD is a cause of dementia. Genetic confirmation should be sought when the condition forms part of the final differential diagnosis. Further studies conducted in the routine clinical setting are now required since it is in this environment that late onset HD is likely to be misdiagnosed in favour of other forms of dementia.  相似文献   
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Pediatric Ablation Charges and Costs Are Rising. Introduction: Catheter ablation has been shown to be effective for pediatric tachyarrhythmias, but the associated charges and costs have not been described in the recent era. Understanding such contemporary trends may identify ways to keep an effective therapy affordable while optimizing clinical outcomes. Methods: We used the 1997–2009 Kids’ Inpatient Databases to examine trends in charges and costs for pediatric catheter ablation and identify determinants of temporal changes. Results: There were 7,130 discharges for catheter ablation in the sample. Mean age at ablation was 12.1 ± 0.2 years. Patients with congenital heart disease (CHD) made up 10% of the sample. Complications occurred in 8% of discharges. Mean total charges rose 219% above inflation (from $23,798 ± 1,072 in 1997 to $75,831 ± 2,065 in 2009). From 2003 to 2009, costs rose 25% (from $20,459 ± 780 in 2003 to $25,628 ± 992 in 2009). Charges for ablation increased markedly relative to surgical procedures, but with a similar slope to other catheter‐based interventions. Multivariable analysis revealed that year (P < 0.0001), payer (P = 0.0002), CHD (P < 0.0001), valvular heart disease (P = 0.0004), cardiomyopathy (P = 0.0009), hospital region (P < 0.0001), length of stay (P < 0.0001), and complications (P < 0.0001) predicted increased charges. The same factors also predicted increased costs. Charges and costs varied considerably by region, particularly for high‐volume centers (P < 0.0001). Conclusions: Charges and costs for pediatric catheter ablation increased relative to other procedures and significantly outstripped inflation. Further study of complications, length of stay, and regional differences may help control rising costs while maintaining quality of care. (J Cardiovasc Electrophysiol, Vol. 24, pp. 162‐169, February 2013)  相似文献   
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