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BACKGROUND: Recent efforts to recruit blood and organ donors have only marginally improved demographic disparities in willingness to donate. Few studies have examined which factors are most important in explaining race and gender disparities in willingness to donate. OBJECTIVES: To assess race and gender differences in willingness to donate blood and cadaveric organs, and to determine the extent to which several factors (including sociodemographic characteristics and attitudes about religion and mistrust of hospitals) might explain differences in willingness to donate. RESEARCH DESIGN: Cross-sectional telephone survey of Maryland households contacted via random-digit dialing. MEASURES: Past blood donation, organ-donor status on driver's license, and measures of medical mistrust and religious and spiritual salience. SUBJECTS: Persons age 18 to 75 living in the Baltimore, Maryland metropolitan area. RESULTS: Of 385 respondents (84% of randomized households), 114 were black females, 46 were black males, 110 were white females, and 69 were white males. Before adjustment, black females were least willing to donate blood (41%), and black males were least willing to become cadaveric donors (19%) among all race-gender groups. Adjustment for respondent concerns about mistrust of hospitals and discrimination in hospitals explained most differences in willingness to donate blood, whereas adjustment for respondents' beliefs regarding the importance of spirituality and religion explained most differences in willingness to donate cadaveric organs. CONCLUSIONS: Both race and gender are important identifiers of those less willing to donate. To maximize efficiency, donor recruitment efforts should focus on race-gender groups with lowest levels of willingness. Potential donor concerns regarding mistrust in hospitals and religion/spirituality may serve as important issues to address when developing programs to improve donation rates.  相似文献   
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The TEPC 15 (T15) clonotype, a putatively germline antibody specificity, does not appear in the neonatal B-cell repertoire until approximately 1 wk of age. This report extends this observation by the demonstration that (a) the T15 clonotype follows similar kinetics of appearance in germfree as well as conventionally-reared mice; (b) maternal influences and genetic background play a minor role in the development of the T15 clonotype since CBFI neonates raised by C57BL/6 or BALB/c mothers acquire the T15 clonotype at the same time in ontogeny as BALB/c neonates; (c) the lack of phosphorylcholine (PC)-specific B cells shortly after birth is reflected in a dearth of PC-binding cells in the neonate as well; and (d) no PC-specifc B cells are found in 19-day fetal liver or in bone marrow until 7 days of life, coincident with their appearance in the spleen. These findings, along with a previous report that PC-specific splenic B cells are tolerizable as late as day 10 after birth, confirm the invariant, late occurrence of the T15 clonotype and support a highly- ordered, rigorously predetermined mechanism for the acquisition of the B- cell repertoire. The results are discussed in light of other studies on the ontogeny of B-cell specificity, and in terms of the implications on the mechanism by which antibody diversity is generated.  相似文献   
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BACKGROUND: Cardiac specialty hospitals assert better patient outcomes and efficiency, whereas general hospitals contend they attract healthier patients. OBJECTIVES: To ascertain whether increased cardiac specialization of a hospital's services is associated with improved outcomes for coronary artery bypass graft (CABG) surgery and whether patients with and without comorbid disease have equivalent outcomes to their counterparts at general hospitals. METHODS: We conducted a retrospective cohort study of a 5% sample of Medicare beneficiaries undergoing CABG procedures from 2001 to 2003. Using multivariate analyses, we assessed the hospital degree of cardiac specialization on mortality, length of stay, hospital readmissions, and emergency room visits leading to rehospitalization for all patients and those with more comorbidities. RESULTS: Patients at cardiac specialty hospitals had less comorbid disease (29.7% with Charlson scores > or =2) than those at moderately (37.2%) and least specialized hospitals (36.6%, P = 0.001). Overall, CABG outcomes in all 3 groups were similar for inpatient mortality (P = 0.78), 30-day postdischarge mortality (P = 0.69), emergency room visit leading to rehospitalization (P = 0.35), and hospital readmission within 30 days postdischarge (P = 0.70). However, for patients with greater comorbidity, 30-day postdischarge mortality was worse at cardiac specialty hospitals compared with least specialized hospitals from across the United States (adjusted odds ratio, 1.71; 95% confidence interval, 1.26-2.32; P = 0.001). Results were robust when hospitals were compared within metropolitan statistical areas. CONCLUSIONS: Favorable patient selection may occur at cardiac specialty hospitals. Although healthier patients fare comparably across types of hospitals, patients with greater comorbid disease seem to experience worse 30-day postdischarge mortality at specialty hospitals.  相似文献   
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BACKGROUND: Women often are less likely than men to receive diagnostic and therapeutic invasive procedures for coronary disease. OBJECTIVE: To examine the relation between gender, health insurance, and access to cardiovascular procedures over time in persons with chronic illness. RESEARCH DESIGN: Seven-year longitudinal analyses in a cohort from the United States Renal Data System. SUBJECTS: National random sample of women and men who progressed to end-stage renal disease (ESRD) in 1986 to 1987 and were treated at 303 dialysis facilities (n = 4,987). MEASURES: Medical history and utilization records, physical examination, and laboratory data. MAIN OUTCOME MEASURES: Receipt of a coronary catheterization or revascularization procedure before (baseline) and after (follow-up) the development of ESRD and acquisition of Medicare, adjusted for clinical and socioeconomic variables. RESULTS: At baseline, 5.2% of women and 9.2% of men had undergone a cardiac procedure; the odds of women receiving a procedure were one third lower than for men (adjusted odds ratio 0.66 [95% CI 0.49-0.88]). During follow-up, women were just as likely as men to undergo a procedure (adjusted odds ratio 0.94 [95% CI 0.74-1.20]). Compared with men with baseline private insurance, men and women with other and no insurance had 34% to 81% lower odds of receiving procedures at baseline. Women with private insurance had 42% lower odds of having a procedure at baseline compared with men (adjusted odds ratio 0.58 [95% CI 0.42-0.78]) but had the same odds at follow-up (adjusted odds ratio 1.09 [95% CI 0.82-1.45]). At follow-up, gender differences in procedure use were eliminated for groups with baseline Medicaid or no insurance. CONCLUSIONS: Overall gender differences in cardiac procedure use were narrowed markedly after progression of a serious illness, the assurance of health insurance, and entry into a comprehensive care system. Gender disparities in procedure use for different baseline insurance groups were largely equalized in follow-up. These findings suggest that provision of insurance with disease-managed care for a chronic disease can provide equalized access to care for women.  相似文献   
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BACKGROUND: Patients with chronic disease who express stronger preference for their current health might be expected to have better outcomes than patients who assign lower utility to their current health state. OBJECTIVE: We sought to examine associations between preferences for current health and outcomes in a national cohort of incident hemodialysis patients. METHODS: In 567 patients treated at 74 clinics, we measured patients' preferences by time trade-off on a 0-1 scale (1=willingness to sacrifice no life expectancy to achieve perfect health; 0=zero value of current health). Associations between these preferences and outcomes were examined with Poisson (hospitalization), logistic (progression of comorbidity and clinical performance), and Cox proportional hazards (mortality) models. RESULTS: The distribution of preference scores was skewed, with a mean of 0.69 and a median of 0.83. Highest (1.0) scores were associated with decreased incidence of hospitalization (incidence risk ratio=0.88, 95% confidence interval=0.80-0.97), relative to the lowest (<0.50) scores, a finding that was consistent across gender and race, with women and white subjects having greater decreases (Pinteraction<0.001). Higher preferences for current health also were associated with less worsening of comorbidity. Adjusted risks of death for patients with intermediate (>or=0.50-1.0) and the highest preference scores for current health were not different from those with lower scores. CONCLUSION: In patients with chronic kidney disease, a stronger preference for current health is associated with lower hospital admission rates and improved comorbidity but not better survival.  相似文献   
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