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61.
The interhemispheric deficit theory of dyslexia postulates that reading difficulties can arise from abnormal communication/collaboration between the cerebral hemispheres. A currently popular way to gather information about interhemispheric processing and integration is with the redundant stimuli task, where participants respond to stimuli presented to the left visual field, right visual field, or both visual fields simultaneously. In neurologically normal individuals, response times to bilateral simple stimulus presentations are faster than response times to a single stimulus in either visual field alone (referred to as redundancy gain). In contrast, individuals with no corpus callosum exhibit greater redundancy gains than would be expected by probability summation. In the present study, 11 children with phonological dyslexia showed a similar "over violation" of the probability (race) model when responding with the left but not the right hand. This asymmetry was not found in age- and IQ-matched control children. The results are at least partially consistent with the notion of phonological dyslexia involving deficits in the transfer of information across the corpus callosum. 相似文献
62.
Rust G Nembhard WN Nichols M Omole F Minor P Barosso G Mayberry R 《American journal of obstetrics and gynecology》2004,191(2):456-462
OBJECTIVE: The purpose of this study was to measure racial and ethnic differences in the proportion of Medicaid patients who receive epidural analgesia during labor and delivery. STUDY DESIGN: Using 1998 Georgia Medicaid claims data in a standard State Medicaid Research File format, we identified claims for epidural analgesia among all women who had a normal vaginal delivery during 1998. RESULTS: There were 29,833 women who met our inclusion criteria, of whom 15,936 (53.4%) had epidural analgesia. Epidural analgesia rates were lower for black women (49.5%), Hispanic women (35.3%), and Asian women (48.1%) than for white, non-Hispanic women (59.6%; P<.001). Rural women had lower epidural rates (39.2%) than urban women (62.1%). CONCLUSION: The study subjects all had identical Medicaid insurance and met the same low-income Medicaid eligibility criteria, yet race/ethnicity was still a significant predictor of epidural analgesia after we had controlled for age, rural-urban residence, and availability of anesthesiologists. Further studies are needed to assess perceived benefits, risks, costs, and obstacles to epidural analgesia that are perceived by patients, physicians, nurses, and midwives. 相似文献
63.
Meade MA Cifu DX Seel RT McKinley WO Kreutzer JS 《Archives of physical medicine and rehabilitation》2004,85(3):368-375
OBJECTIVE: To examine the role of race on rehabilitation outcomes for a matched sample of patients with spinal cord injury (SCI). DESIGN: African Americans and whites with SCI were matched based on age group, level and completeness of injury, and sponsor of care to retrospectively analyze the impact of race. SETTING: Eighteen medical centers in the federally sponsored Model Spinal Cord Injury Systems project. PARTICIPANTS: A total of 628 adults with SCI. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Medical procedures and complications; American Spinal Injury Association motor index, and FIMT instrument scores at admission and discharge; and discharge dispositions. RESULTS: Analysis revealed race-related differences in spinal surgeries, laparotomies, traction during acute care, and method of bladder management at discharge. In most cases, these were explained by cause of injury rather than direct affects of race. No differences were found with regard to medical complications functional outcomes, or discharge disposition. CONCLUSIONS: Although differences exist in the medical procedures given to African Americans and whites with SCI, they are generally accounted for by cause of injury rather than the direct affects of race. 相似文献
64.
Meade MA Lewis A Jackson MN Hess DW 《Archives of physical medicine and rehabilitation》2004,85(11):1782-1792
OBJECTIVES: To examine issues of employment and race for persons with spinal cord injury (SCI), by assessing the type of work that was being done before and after injury and by placing this in the context of patterns for the general population. DESIGN: Retrospective, cross-sectional analysis. SETTING: Centers funded as part of the federally sponsored Model Spinal Cord Injury Systems (MSCIS) Project. PARTICIPANTS: Two samples: 5925 African Americans and whites with SCI who are part of the MSCIS and a subset of 577 people with SCI. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Demographic information, occupational status, employment rate, job census codes, Craig Hospital Assessment and Reporting Technique-Short Form, and Satisfaction With Life Scale. RESULTS: Racial disparities were found in employment rates before injury and at 1, 5, 10, 15, and 20 years after SCI. Differences were also found in the types of jobs that were held before SCI with patterns for participants similar to those of African Americans and whites in the general population. No differences were found in the types of jobs held by African Americans and whites with SCI at 1 year after injury. After injury, African Americans had lower economic self-sufficiency scores, regardless of employment status, and lower social integration scores among those who were not employed. CONCLUSIONS: Racial disparities found in employment patterns among persons with SCI mirrored patterns among the general population. 相似文献
65.
Areas with higher absolute poverty and higher income inequality have been associated with higher risk of homicide victimization.
In addition, studies of differential homicide rates have indicated that black persons are at a higher risk of homicide compared
to white persons. However, few studies directly compared risk of homicide offending or victimization between Hispanic persons
and non-Hispanic white persons, and few studies have attempted to examine the interaction between race and residential neighborhood
socioeconomic measures on homicide risk. This population-based retrospective study comprised all white, black, and Hispanic
15-to 44-year-old men included in the 1990 US Census as Rhode Island or Massachusetts residents. Vital statistics registries
were linked to 1990 US Census data to provide information on small-area characteristics. Overall, we observed a trend of increasing
homicide risk as block-group socioeconomic position descended. The data indicated that block-group poverty, female-headed
households, home ownership, and higher education were all strongly associated with homicide risk after stratifying by race
and age of victim and adjusting for other block-group socioeconomic characteristics. Race was a strong modifier for absolute
risk difference for the relation between risk of homicide and socioeconomic surroundings. Our analyses suggested that area-based
interventions that would improve neighborhood social and economic conditions would be effective in decreasing risk of homicide
for men. 相似文献
66.
Summary Objectives: To analyse disability trends over the 1980s–1990s in gender and race groups of early retirement ages in USA.Methods: Disability trends for white and black males and females aged 65–69 and 70+ are analysed using the 1982–1999 NLTCS. Disability is analysed at three levels (instrumental activities of daily living (IADL), activities of daily living (ADL), and institutionalisation).Results: 1) A larger increase in proportions of non-disabled blacks aged 65–69 compared with whites and males compared with females. 2) Differences in disability trends among gender and race groups. 3) A faster absolute decline in non-institutionalised disabled aged 65–69. 4) A larger absolute decline and a smaller relative decline in proportions of disabled aged 70+ compared with 65–69. 5) A significant decrease in the proportion of ADL disabled blacks and an increase of ADL disabled white females in the age group 70+.Conclusions: Americans aged 65–69 years manifest a significant improvement in health over the 1980s–1990s but the dynamics differs in gender and race groups. Possible reasons for these differences are discussed. 相似文献
67.
A Comparison Study of the Reference Curves of Bone Mineral Density at Different Skeletal Sites in Native Chinese,Japanese, and American Caucasian Women 总被引:22,自引:0,他引:22
To understand the differences among reference curves for bone mineral density (BMD) for Chinese, Japanese, and American Caucasian women, we measured the BMD at the anteroposterior (AP) lumbar spine (L1–L4), lateral lumbar spine (L2–L4), hip (including the femoral neck, trochanter, intertrochanter, Wards triangle, and total hip), and ultradistal forearm by the dual-energy X-ray absorptiometry (DXA) in a total of 2728 healthy Chinese women, aged 5–96 years. Documented BMD data for Japanese women and device manufacturers BMD new reference databases (including the NHANES III dataset) for American Caucasian women were also used in this study. The cubic regression model was found to fit best in analyzing the age-associated variations of BMD at various sites in Chinese women, i.e., the equations had the largest coefficient of determination (R
2). At the AP/Lat spine, trochanter, intertrochanter, and Wards triangle, BMD reference curves for Chinese women were lower than those for Japanese or Caucasian women, while at the femoral neck, total hip, and ultradistal forearm, the reference curves for Chinese women were higher than those for Japanese women, with overlaps and crossing of the curves for some age spans in comparing the Chinese and Caucasian women. There were significant differences in the peak BMD (PBMD) at various sites among the Chinese, Japanese, and Caucasian women (P = 0.000). The PBMDs for Chinese women at the lumbar spine and various sites of the hip were 5.7% ± 2.1% (mean ± SD, range, 2.7–7.9%) lower than those for Japanese women and 5.1% ± 2.7% (range, 0.5–7.2%) lower than those for Caucasian women; however, the PBMDs for Chinese women were 26.2% higher than those for Japanese women and 10% higher than those for Caucasian women at the ultradistal forearm. After the PBMD, average T-scores of Chinese women for losses at the AP lumbar spine with increasing age were nearly identical to those for Japanese women, but both were greater than those for Caucasian women. The average T-scores for BMD loss at various sites in Chinese women were higher than those for both Japanese and Caucasian women except at the femoral neck, where the T-scores of Chinese women were exceeded by those of both Japanese and Caucasian women. Estimated from the T-score curve of BMD loss, the age of osteoporosis occurrence at the femoral neck in Chinese women was about 10 years later than that in Japanese or Caucasian women; at the AP spine, Chinese women were similar to Japanese women; at the other sites, the age for occurrence of osteoporosis in Chinese women was about 5–15 years earlier than that in either Japanese or Caucasian women. There are differences in prevalence or odds ratio (OR) of osteoporosis at the same skeletal region for Chinese, Japanese, and Caucasian women aged 50 years or at different skeletal regions in women of the same race. The prevalences of osteoporosis at various regions of the hip in Chinese women are 10.1–19.8% and ORs are 22.0–32.3, of which prevalence at the femoral neck is the lowest (10.1%); the prevalences of osteoporosis in Japanese women are 11.6–16.8% and ORs are 21.1–26.3, of which prevalence at the femoral neck is the lowest (11.6%); and the prevalences of osteoporosis in Caucasian women are 13.0–20.0% and ORs are 19.4–48.9, of which prevalence at the femoral neck is the highest (20%). In conclusion, racial differences in BMD reference curves, prevalences, and risks of osteoporosis at various skeletal sites exist among native Chinese, Japanese, and American Caucasian women. 相似文献
68.
Examining gender, racial, and age differences in weight concern among third, fifth, eighth, and eleventh graders 总被引:2,自引:0,他引:2
Weight management and concern, body weight beliefs, and perceptions of friend's and family's weight concerns were examined in this study by race, grade, and gender. A stratified random sample was used to select schools within nine districts in South Carolina and an anonymous self-report paper-pencil questionnaire was completed by the students. The final sample included 3151 African American (42.3%) and White (57.7%) children (51.7% female) in the third (n=599), fifth (n=686), eighth (n=1168), and eleventh (n=698) grades. White girls were more likely to report being overweight (P=.0042), having higher personal weight concerns (P<.0001), and perceiving higher friend (P<.0001) and family weight concerns (P<.0001) than the African American girls. Using multiple regression, 29.8% of the variance in the children's personal weight concern scores was explained by perceptions of family's weight concerns (R(2)=.1659), gender (R(2)=.0762), perceptions of friend's weight concerns (R(2)=.0392), grade (R(2)=.0094), a Race x Gender interaction (R(2)=.0042), and race (R(2)=.003). Most of the children, particularly the white girls, have personal weight concerns and dieting practices which place them at risk for possible health problems. These results support the need for nutrition interventions and education in early childhood. Programs to prevent obesity and eating disorders should be tailored for differences by gender, grade, and race. 相似文献
69.
Blood pressure, heart rate, and changes in facial and finger blood flow were monitored in 24 male Chinese and 24 male Caucasians while they described anger-provoking incidents and read out neutral material, either loudly and rapidly or softly and slowly. Describing the incidents loudly and rapidly heightened anger ratings and enhanced digital vasoconstriction but not blood pressure or heart rate; however, anger enhanced blood pressure during soft, slow speech. Facial blood flow increased during anger expression, irrespective of speech style, but decreased when neutral material was read out. The findings suggest that an increase in facial blood flow reduces peripheral vascular resistance during anger expression, and that baroreflexes attenuate increases in heart rate and blood pressure. Racial background did not influence subjective reports or physiological responses, possibly because the procedure did not draw strongly enough on cultural taboos. 相似文献
70.
Objective: To investigate the contribution of body mass index (BMI) to mortality over 11 years of follow-up in a prevalent sample of
dialysis patients aged 60+. Design: Multivariate Cox proportional hazards regression analysis. Setting: Multicenter stratified random sample of black and white older chronic dialysis patients in a southeastern state. Subjects: 316 patients on hemodialysis (HD) and peritoneal dialysis (PD). Main outcome measure: Continued survival from baseline interview in 1988 to June1999. Results: Adjusting for age, primary diagnosis of diabetes, cardiovascular comorbidity, HD/PD therapy, and patient-reported functional
impairment, the interaction of baseline BMI with race and gender was associated with older patients' risk of mortality. Black
females, black males, and white males with higher BMI had a reduced risk of mortality, while no protective effect of higher
BMI was found for white females. Patients with cardiovascular comorbidity and greater functional impairment at baseline had
increased mortality risk. BMI was not significantly correlated with serum albumin or functional impairment. Conclusion: BMI, a simple anthropometric measure that provides a marker of nutritional status,interacts with race and gender to predict
long-term survival in older dialysis patients. The association of survival with dialysis adequacy,nutritional indicators,
and cardiovascular status in black and white dialysis patients is an important area of study.
This revised version was published online in September 2006 with corrections to the Cover Date. 相似文献