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Until recently, bioethics (ethics related to biology or, more specifically, in the context of preterm labour, medical ethics) was considered mainly to relate to the active treatment or investigation of patients. Collection of data, excised specimens or even whole organs was considered to be relatively uncontentious as it did not impinge directly upon the health of the individual concerned. However, in the UK in particular, the practice of collecting data, tissues or even whole organs has recently come under the spotlight of public scrutiny, particularly following the Alder Hey Enquiry. Coincidentally with a decline in public confidence in the probity of authority, medical scientists increasingly have to justify the accumulation of data about individuals.  相似文献   
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Phytochemical-mediated modulation of P-glycoprotein (P-gp) and other drug transporters may give rise to many herb-drug interactions. Serial plasma concentration-time profiles of the P-gp substrate, digoxin, were used to determine whether supplementation with goldenseal or kava kava modified P-gp activity in vivo. Twenty healthy volunteers were randomly assigned to receive a standardized goldenseal (3210 mg daily) or kava kava (1227 mg daily) supplement for 14 days, followed by a 30-day washout period. Subjects were also randomized to receive rifampin (600 mg daily, 7 days) and clarithromycin (1000 mg daily, 7 days) as positive controls for P-gp induction and inhibition, respectively. Digoxin (Lanoxin, 0.5 mg) was administered p.o. before and at the end of each supplementation and control period. Serial digoxin plasma concentrations were obtained over 24 h and analyzed by chemiluminescent immunoassay. Comparisons of area under the curve (AUC)((0-3)), AUC((0-24)), C(max,) CL/F, and elimination half-life were used to assess the effects of goldenseal, kava kava, rifampin, and clarithromycin on digoxin pharmacokinetics. Rifampin produced significant reductions (p < 0.01) in AUC((0-3)), AUC((0-24)), CL/F, t(1/2), and C(max), whereas clarithromycin increased these parameters significantly (p < 0.01). With the exception of goldenseal's effect on C(max) (14% increase), no statistically significant effects on digoxin pharmacokinetics were observed following supplementation with either goldenseal or kava kava. When compared with rifampin and clarithromycin, supplementation with these specific formulations of goldenseal or kava kava did not appear to affect digoxin pharmacokinetics, suggesting that these supplements are not potent modulators of P-gp in vivo.  相似文献   
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Preclinical and clinical investigations currently underway are employing novel strategies for combining vaccines with conventional and experimental anticancer therapies. To date, the FDA has not approved a therapeutic cancer vaccine. However, the results of recent investigations suggest an increasing role for vaccines in new models of combination therapy for many types of cancer. This article reviews and discusses therapeutic cancer strategies that employ vaccines in combination with local radiation, chemotherapy, hormone therapy, and anti-CTLA-4 mAb. Preclinical studies have shown that certain anticancer agents have immune modulatory effects that result in up-regulation of surface expression of MHC molecules, tumor-associated antigens, or Fas on malignant cells, rendering them more susceptible to immune destruction. Preliminary results of clinical studies using combination strategies have demonstrated a postvaccination antigen cascade, prolonged time to disease progression, and improved overall survival. Several larger randomized trials are ongoing, and more are required to support these findings.  相似文献   
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Single parent women   总被引:1,自引:1,他引:0  
Summary While there has been considerable interest in the problems of single parent families, no study has yet determined if the problems are due to increased risk of specific psychiatric disorders in single parents as compared to their married counterparts. Data collected as part of the National Institute of Mental Health Epidemiologic Catchment Area (ECA) Project are presented to compare the psychiatric as well as economic and social functioning of single vs. married parent women ages 18–44, based on a probability sample of members of the greater New Haven community. The major finding between groups is their relative similarity in psychiatric as well as social functioning. The major difference is economic. Single parents, both Black and White, more frequently are less educated and poorer. While many are on welfare, single compared to married female parents are more likely to be working and to report insufficient income to meet their needs. There are no appreciable differences in social contacts, use of health services or six-month prevalence rates of psychiatric disorders including major depression, alcohol or drug abuse. The data suggest that the problems faced by single parent women and their children may be a reflection of poverty and stress in families and not of psychiatric disorders or poor social relations in mothers.  相似文献   
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AIMS: To evaluate the relationship between echocardiographic cardiac function and outcome in patients with stable symptomatic angina. METHODS: Baseline echo left ventricular ejection fraction and volume data measured in a central laboratory was available for 7016 patients (92% of the total) participating in the ACTION trial (A Coronary disease Trial Investigating Outcome with Nifedipine GITS). Ejection fraction was also measured by investigators. Evaluation of the different echocardiographic variables was based on adjusted hazard ratios comparing the unfavourable limit of the 90% range of the variable concerned to the favourable limit. RESULTS: The centrally measured ejection fraction was the most powerful predictor of all-cause death (adjusted hazard ratio=2.5), myocardial infarction, any stroke or transient ischaemic attack and overt heart failure (adjusted hazard ratio=4.5). The addition of either end systolic volume or end diastolic volume to ejection fraction did not materially affect the power of prediction. Compared to the central ejection fraction measurement, the investigator-measured ejection fraction was a less powerful predictor for all outcomes considered. CONCLUSION: Routine echocardiography carefully analysed by standardised methods provides useful prognostic information in patients with stable angina, including for total mortality.  相似文献   
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