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BACKGROUND: African Americans (AAs) have a higher prevalence of obesity and type 2 diabetes than do whites. Higher insulin resistance and hyperinsulinemia have been reported in adult AAs than in whites. Differences in adipose tissue and its distribution may account for these findings. OBJECTIVE: The objective was to ascertain whether differences between AA and white women in adipose tissue (AT) and skeletal muscle (SM) volumes account for ethnic differences in insulin resistance. DESIGN: We used whole-body magnetic resonance imaging to measure AT and SM volumes and used the intravenous-glucose-tolerance test to measure insulin resistance. RESULTS: AAs (n = 32) were 29-42% more insulin resistant than were whites (n = 28) after adjustment for weight and height or any AT volumes (P < 0.05). After adjustment for SM volume, the difference decreased to 19% and became nonsignificant. AAs had a 163% greater acute insulin response to glucose than did whites; this difference was significant even after adjustment for insulin sensivitity index, weight, height, and any magnetic resonance imaging measures. With respect to regional AT volumes, an association independent of race, weight, height, and SM volume was found only between increased intermuscular AT and lower insulin sensitivity index. CONCLUSIONS: Premenopausal AA women had significantly higher insulin resistance and acute insulin response to glucose than did their white counterparts. Whereas the difference in insulin resistance was partially accounted for by a greater SM volume in the AAs than in the whites, the difference in the acute insulin response to glucose was independent of any AT and SM measures and was disproportionately larger than expected according to the difference in insulin resistance. In addition, whole-body intermuscular AT was an important independent correlate of insulin resistance.  相似文献   
83.
There can be considerable interinstitutional distrust regarding transfer of psychiatric patients. In 1970 the directors of all psychiatric hospitals in New York City began to meet regularly in order to define problems and work out amicable resolutions, largely by defining criteria for hospitalization, establishing correct catchment area address, etc. In order to test the success of the program, three medical centers which routinely transfer patients to a receiving hospital were studied in order to see if they misrepresented patients' psychopathology or medical problems prior to transfer. It was found that 90% of the transfers were warranted, but that preselection at the hospital of origin led to the transfer of more males than females and more assaultive, rather than quieter patients, who might have been more amenable to inpatient treatment.The authors wish to thank Dr. Linda Brady for her assistance in reviewing charts and following up patients.  相似文献   
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Children with signs of slipping of the upper femoral epiphysis often present in an Accident Service, particularly after a severe, acute slip. In some cases the displacement is irreducible and correction of the persistent deformity by either cervical or trochanteric osteotomy is required. This paper is a review of 14 cases of irreducible slipped upper femoral epiphysis treated by subtrochanteric osteotomy. Clinical and radiological assessment of these cases some years later shows a high proportion of successful results and suggests that this is a safe and satisfactory method of treating this condition.  相似文献   
87.
In this study, we examined genetic and environmental influences on covariation among two reading tests used in neuropsychological assessment (Cambridge Contextual Reading Test [CCRT], [Beardsall, L., and Huppert, F. A. (1994). J. Clin. Exp. Neuropsychol. 16:232-242], Schonell Graded Word Reading Test [SGWRT], [Schonell, F. J., and Schonell, P. E. (1960). Diagnostic and attainment testing. Edinburgh: Oliver and Boyd.]) and among a selection of IQ subtests from the Multidimensional Aptitude Battery (MAB), [Jackson, D. N. (1984). Multidimensional aptitude battery, Ontario: Research Psychologists Press.] and the Wechsler Adult Intelligence Scale-Revised (WAIS-R) [Wechsler, D. (1981). Manual for the Wechsler Adult Intelligence Scale-Revised (WAIS-R). San Antonio: The Psychological Corporation]. Participants were 225 monozygotic and 275 dizygotic twin pairs aged from 15 years to 18 years (mean, 16 years). For Verbal IQ subtests, phenotypic correlations with the reading tests ranged from 0.44 to 0.65. For Performance IQ subtests, phenotypic correlations with the reading tests ranged from 0.23 to 0.34. Results of Structural Equation Modeling (SEM) supported a model with one genetic General factor and three genetic group factors (Verbal, Performance, Reading). Reading performance was influenced by the genetic General factor (accounting for 13% and 20% of the variance for the CCRT and SGWRT, respectively), the genetic Verbal factor (explaining 17% and 19% of variance for the CCRT and SGWRT), and the genetic Reading factor (explaining 21% of the variance for both the CCRT and SGWRT). A common environment factor accounted for 25% and 14% of the CCRT and SGWRT variance, respectively. Genetic influences accounted for more than half of the phenotypic covariance between the reading tests and each of the IQ subtests. The heritabilities of the CCRT and SGWRT were 0.54 and 0.65, respectively. Observable covariance between reading assessments used by neuropsychologists to estimate IQ and IQ subtests appears to be largely due to genetic effects.  相似文献   
88.
BACKGROUND: This study describes the use of retrievable IVC filters in a select group of trauma patients at high risk for deep vein thrombosis (DVT) and pulmonary embolism (PE). STUDY DESIGN: Retrievable IVC filters were placed in selected trauma patients who met high-risk criteria for deep vein thrombosis and PE according to institutional clinical management guidelines. All filters were placed percutaneously in the interventional radiology suite. Indications for filter placement were based on injury complex, weight-bearing status, and contraindications to enoxaparin or pneumatic compression devices. IVC filters were either removed or maintained. RESULTS: Retrievable IVC filters were placed in 35 patients after blunt trauma. Twenty-six patients (74%) sustained at least one orthopaedic injury; 17 patients (49%) were diagnosed with a pelvis fracture. Activity was limited to bed rest or spinal precautions in 18 patients (51%). Enoxaparin was contraindicated in 32 patients (91%) and injuries precluded the use of pneumatic compression devices in 11 (31%). IVC filters were removed in 18 patients (51%), with no reported complications. Patients with orthopaedic injuries and pelvis fractures were less likely to have their filters maintained (p = 0.040). CONCLUSIONS: Retrievable IVC filters offer a versatile option for prophylaxis in trauma patients at high risk for PE. Filter retrieval potentially spares the longterm complications of permanent filters in younger trauma patients. Retrievable filters warrant consideration in patients who meet high-risk criteria for deep vein thrombosis or PE who cannot receive effective mechanical prophylaxis and in whom contraindications to anticoagulation are expected to be temporary.  相似文献   
89.
OBJECTIVES: The purpose of this paper was to evaluate the use of air displacement plethysmography (ADP) in children and adolescents with cystic fibrosis (CF). Specifically, the primary aim of this study was to compare estimates of fat-free mass (FFM) measured from ADP and dual energy X-ray absorptiometry (DEXA) in children and adolescents with CF. The secondary aim was to compare the effect of using predicted thoracic gas volume (VTG) and measured VTG for the calculation of FFM by ADP in this population. METHODS: Cross-sectional FFM measurements were taken using ADP and DEXA in 52 children and adolescents with CF, ranging in age from 6.3 to 16.6 y. RESULTS: Bland-Altman analysis showed that ADP values of FFM were on average 0.59 kg higher than DEXA values (95% limits of agreement = 3.61 to -2.43 kg); however this difference was not significant. There was no significant correlation (r = -0.26, P = 0.07) between the mean FFM and difference in FFM between ADP and DEXA. Using either predicted or measured VTG did not significantly affect FFM estimates in individuals with CF who had normal lung function (bias = -0.39 +/- 0.86 kg; r = -0.02, P = 0.93). CONCLUSIONS: ADP is an appropriate technique for use in children and adolescents with CF.  相似文献   
90.
Recent findings indicate that prenatal protein restriction, which leads to elevated blood pressure in adult rats, results in decreased levels of docosahexaenoic acid (DHA) in neonatal rat brain. In light of the evidence of a relationship between dietary DHA and adult blood pressure, the purpose of this study was to ascertain whether prenatal dietary supplementation with DHA would prevent the development of hypertension associated with maternal protein restriction. Throughout gestation, female Wistar rats were fed isocaloric diets containing either 18% casein + 10% corn oil (CON; control), 9% casein + 10% corn oil (LP; low-protein) or 9% casein + 8.5% corn oil + 1.5% DHASCO (LP + 0.6% DHA). DHA increased levels of DHA in neonatal forebrain but there were no effects of LP. At 10 weeks there were no dietary effects on blood pressure measured on four consecutive days using tail-cuff plethysmography. There were also no significant effects measured at 30 weeks, using femoral artery catheterisation, despite adequate power to detect a 10 mm Hg difference. Trends in corticosterone measurements suggested higher stress reactivity in the LP group. These results do not provide strong support for the prenatal low protein model of hypertension and a relation with dietary DHA.  相似文献   
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