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Race, biology, and health care: reassessing a relationship   总被引:2,自引:0,他引:2  
Recent reports reaffirm huge disparities in the health of blacks compared to other Americans. These disparities persist in part because of the current attempt by health policy makers to frame racially based health differences in non-racial terms. Yet an historical analysis shows that since ancient times, blacks have been the victims of racism in the biomedical sciences; health-system discrimination and deprivation; and later, medical and scientific exploitation. Race- and class-based structuring of the health delivery system has combined with other factors, including physicians' attitudes conditioned by their participation in slavery, and the scientific myth of black biological and intellectual inferiority, to establish a "slave health deficit" that has never been corrected. Until the persistent institutional racism and racial discrimination in health policy, health delivery, and medical educational systems are eradicated, African-Americans will continue to experience poor health outcome.  相似文献   
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A population based hybrid design combining element of cohort and cross-sectional approach was used to develop a simple clinical algorithm to predict individual probability of developing hypertension (systolic BP > 140 mm Hg and/or diastolic BP > 90 mmHg). 3615 soldiers initially normotensive at the time of induction into high altitude, were studied by systematic random sampling. Multiple logistic regression analysis showed a high significant association between hypertension and age, body mass index (BMI), tobacco smoking and alcohol consumption. Using the constant/coefficient values obtained from the logistic model and the receiver operating characteristics (ROC) curve analysis, the following predictive rule was developed – To the age in years, add (BMIx 3.86); also add 5.53 if he is a smoker; and add 19.81 if he consumes alcohol. If the total exceeds 142, the individual is at high risk of developing hypertension. This algorithm carries a sensitivity of 68.2% and specificity of 78.5%.KEY WORDS: Hypertension, High altitude  相似文献   
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Objective Analyses of bladder cancer mortality in the Black Foot Disease (BFD) endemic area of southwest Taiwan conducted by Morales et al. showed a discontinuity in risk at 400 μg/L arsenic in the drinking water in a stratified analysis and no discontinuity in a continuous analysis.  相似文献   
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Hydroxyapatite is a biocompatible alloplast with the same chemical composition as bone. It is readily incorporated into host bone, does not undergo appreciable resorption, does not incite a clinically significant foreign body reaction, and resists infection. This article describes forms of hydroxyapatite, procedures for use, and clinical examples.  相似文献   
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PURPOSE: Rituximab has clinical activity in patients with chronic lymphocytic leukemia (CLL) and has a variety of proposed mechanisms, including apoptosis, complement-dependent cell lysis (CDC), and antibody-dependent cellular cytotoxicity (ADCC). Here we examine pretreatment biologic features that promote resistance to apoptosis and CDC in CLL patients and correlate it with clinical outcome to rituximab-based therapy. PATIENTS AND METHODS: Pretreatment samples from 21 CLL patients treated on a prospective, single-agent rituximab trial were examined for quantitative expression of apoptotic and CDC regulatory proteins, and the level of expression of these proteins was correlated with clinical outcome. RESULTS: Of the 21 patents for whom samples were available, 10 attained a partial response and 11 failed to respond to rituximab therapy. The mean pretreatment expression of Bcl-2, Mcl-1, XIAP, and the ratio of Bcl-2/Bax were higher but not statistically increased in nonresponding patients versus those responding to treatment. In contrast, the pretreatment Mcl-1/Bax ratio was significantly elevated (0.82 +/- 0.28 v 0.39 +/- 0.29, P <.016) in nonresponding patients compared with patients responding to rituximab therapy. Although pretreatment expression of CD55 and CD59 was not associated with response to rituximab therapy, significantly higher levels of CD59 were observed in the CLL cells that were not cleared from the blood at completion of therapy than the level observed at baseline levels (P =.02). CONCLUSION: These data indicate that baseline expression of the Mcl-1/Bax ratio, but not CD55 and CD59, predict for clinical response to rituximab therapy in CLL patients. Further study of disrupted apoptosis in CLL as a potential mechanism of resistance to rituximab appears warranted.  相似文献   
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PURPOSE: Flavopiridol has in vitro activity in chronic lymphocytic leukemia (CLL) and promotes apoptosis independent of p53 function or prior fludarabine exposure. We sought to determine if flavopiridol has activity in previously treated CLL using two schedules of administration. PATIENTS AND METHODS: Patients with previously treated CLL were enrolled in two sequentially done phase II studies. Patients in the first trial received flavopiridol (50 mg/m(2)/d) as a continuous infusion (CI) for 72 hours every 2 weeks. Patients in the second trial received flavopiridol 50 mg/m(2) as a 1-hour bolus (IVB) daily for 3 days repeated every 3 weeks. Patients received up to 12 (CI cohort) or 8 (IVB cohort) cycles of therapy. RESULTS: Fifteen patients were enrolled in the 72-hour CI phase II trial; 6 (40%) had intermediate-risk (Rai stage I or II) and 9 (60%) had high-risk (Rai stage III and IV) stages. No responses were noted in this group; 27% had stable disease and 73% had progressive disease. Thirty-six patients were enrolled in the second IVB trial, with 13 (36%) having intermediate and 23 (64%) having high-risk disease. Four patients (11%) had partial responses, 19 (53%) had stable disease, and 13 (36%) had progressive disease. The progression-free survival for responders in the IVB trial was 3, 3, 9, and 19 months. The median progression-free survival was 2 months [95% confidence interval (95% CI), 1.8-3.8] for patients in the CI trial and 3 months (95% CI, 2.5-7.4) for the IVB trial. The median overall survival was 27 months (95% CI, 20-42) for the CI trial and 24 months (95% CI, 18-31) for the IVB trial. Toxicity was manageable and included mainly myelosuppression, infections, diarrhea, and fatigue. CONCLUSIONS: Flavopiridol has modest, schedule-dependent clinical activity in relapsed CLL and warrants future investigation utilizing alternative schedules of administration.  相似文献   
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Cardiovascular (CV) toxicities of the Bruton tyrosine kinase (BTK) inhibitor ibrutinib may limit use of this effective therapy in patients with chronic lymphocytic leukemia (CLL). Acalabrutinib is a second-generation BTK inhibitor with greater BTK selectivity. This analysis characterizes pooled CV adverse events (AE) data in patients with CLL who received acalabrutinib monotherapy in clinical trials (clinicaltrials gov. Identifier: NCT02029443, NCT02475681, NCT02970318 and NCT02337829). Acalabrutinib was given orally at total daily doses of 100–400 mg, later switched to 100 mg twice daily, and continued until disease progression or toxicity. Data from 762 patients (median age: 67 years [range, 32–89]; median follow-up: 25.9 months [range, 0–58.5]) were analyzed. Cardiac AE of any grade were reported in 129 patients (17%; grade ≥3, n=37 [5%]) and led to treatment discontinuation in seven patients (1%). The most common any-grade cardiac AE were atrial fibrillation/flutter (5%), palpitations (3%), and tachycardia (2%). Overall, 91% of patients with cardiac AE had CV risk factors before acalabrutinib treatment. Among 38 patients with atrial fibrillation/flutter events, seven (18%) had prior history of arrhythmia or atrial fibrillation/flutter. Hypertension AE were reported in 67 patients (9%), 43 (64%) of whom had a preexisting history of hypertension; no patients discontinued treatment due to hypertension. No sudden cardiac deaths were reported. Overall, these data demonstrate a low incidence of new-onset cardiac AE with acalabrutinib in patients with CLL. Findings from the head-to-head, randomized trial of ibrutinib and acalabrutinib in patients with high-risk CLL (clinicaltrials gov. Identifier: NCT02477696) prospectively assess differences in CV toxicity between the two agents.  相似文献   
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