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Eschbach K  Mahnken JD  Goodwin JS 《Cancer》2005,103(5):1036-1044
BACKGROUND: Hispanics in the United States have a 33% lower age-adjusted incidence of cancer and a 38% lower cancer mortality rate compared with non-Hispanic whites. This may be secondary to health behaviors that vary with residential and economic assimilation. The authors investigated whether cancer incidence among Hispanics increased with residential and economic assimilation into mainstream culture. METHODS: Data from the Surveillance, Epidemiology, and End Results program (SEER) and the U.S. Census Bureau were used to compare cancer incidence rates and rate ratios as a function of percentage of Hispanics and income of Hispanics in a census tract. Type of cancer was identified with a site recode variable in the SEER data set. Cases with in situ prostate and cervical carcinoma were excluded. Hispanic ethnicity in SEER was identified by medical record review and Hispanic surname lists. The study also used income of Hispanics living in the census tract, age at diagnosis, and stratification by gender. RESULTS: The incidence of breast, colorectal, and lung carcinoma among Hispanics increased as the percentage of Hispanics in the census tract decreased and as tract Hispanic income increased. For example, there was a 39% reduction in breast carcinoma and a 38% reduction in male colorectal carcinoma when the Hispanic population in high-density Hispanic neighborhoods in the lowest income quartile was contrasted to Hispanics living in tracts with the lowest total percentage of Hispanics in the highest income quartile. CONCLUSIONS: The lower cancer rates among Hispanics relative to non-Hispanic whites in the United States may dissipate as Hispanics become more assimilated into the mainstream society.  相似文献   
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STUDY OBJECTIVE: Research suggests that economically disadvantaged neighbourhoods confer an increased risk of depression to their residents. Little research has been reported about the association between ethnic group concentration and depression. This study investigated the association between neighbourhood poverty and neighbourhood percentage Mexican American and depressive symptoms for older Mexican Americans in the south western United States. DESIGN: A population based study of older non-institutionalised Mexican Americans from the baseline assessment (1993/94) of the Hispanic established population for the epidemiologic study of the elderly (H-EPESE) merged with 1990 census data. SETTING: Five south western states in the United States. PARTICIPANTS: 3050 Mexican Americans aged 65 years or older. MAIN RESULTS: There was a strong correlation between the percentage of neighbourhood residents living in poverty and the percentage who were Mexican American (r = 0.62; p<0.001). Percentage neighbourhood poverty and percentage Mexican American had significant and opposite effects on level of depressive symptoms among older Mexican Americans. After adjusting for demographic and other individual level factors, each 10% increase in neighbourhood population in poverty was associated with a 0.763 (95% CI 0.06 to 1.47) increase in CES-D score, while each 10% increase in Mexican American neighbourhood population was associated with a -0.548 (95% CI -0.96 to -0.13) unit decrease in CES-D score among older Mexican Americans residing in their neighbourhoods. CONCLUSIONS: The findings suggest a sociocultural advantage conferred by high density Mexican American neighbourhoods, and suggest the need to include community level factors along with individual level factors in community based epidemiological health studies.  相似文献   
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Optimization of a previously disclosed sorbitol dehydrogenase inhibitor (SDI, II) for potency and duration of action was achieved by replacing the metabolically labile N,N-dimethylsulfamoyl group with a variety of heterocycles. Specifically, this effort led to a series of novel, in vitro potent SDIs with longer serum half-lives and acceptable in vivo activity in acutely diabetic rats (e.g., 62, 67, and 69). However, the desired in vivo potency in chronically diabetic rats, ED90 less than or equal to 5 mg/kg/day, was achieved only through further modification of the piperazine linker. Several members of this family, including 86, showed better than the targeted potency with ED90 values of 1-2 mg/kg/day. Compound 86 was further profiled and found to be a selective inhibitor of sorbitol dehydrogenase, with excellent pharmacodynamic/pharmacokinetic properties, demonstrating normalization of sciatic nerve fructose in a chronically diabetic rat model for approximately 17 h, when administered orally at a single dose of 2 mg/kg/day.  相似文献   
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Oscillatory motion of the normal cervical spinal cord   总被引:2,自引:0,他引:2  
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