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Michiels S  Hill C 《The New England journal of medicine》2007,356(15):1582; author reply 1583-3; author reply 1583
  相似文献   
996.
The aim of this study was to introduce high-resolution computed tomography (CT) of breast tumours using the diffraction-enhanced x-ray imaging (DEI) technique and to compare results with radiological and histo-pathological examinations. X-ray CT images of tumour-bearing breast tissue samples were acquired by monochromatic synchrotron radiation (SR). Due to the narrow beam and a large sample-to-detector distance scattering is rejected in the absorption contrast images (SR-CT). Large contrast enhancement is achieved by the use of the DEI-CT method, where the effects of refraction and scatter rejection are analysed by crystal optics. Clinical mammograms and CT images were recorded as reference material for a radiological examination. Three malignant and benign samples were studied in detail. Their radiographs were compared with optical images of stained histological sections. The DEI-CT images map accurately the morphology of the samples, including collagen strands and micro-calcifications of dimensions less than 0.1 mm. Histo-pathological examination and reading of the radiographs were done independently, and the conclusions were in general agreement. High-resolution DEI-CT images show strong contrast and permit visualization of details invisible in clinical radiographs. The radiation dose may be reduced by an order of magnitude without compromising image quality, which would make possible clinical in vivo DEI-CT with future compact SR sources.  相似文献   
997.

Background

Oral disease, despite being largely preventable, remains the most common chronic disease worldwide and has a significant negative impact on quality of life, particularly among older adults.

Objective

This study is the first to comprehensively and at a large scale (14 European countries) measure the social inequalities in the number of natural teeth (an informative oral health marker) in the over 50-year-old population and to investigate the extent to which such inequalities are attributable to dental service use.

Methods

Using Wave 5 of the Survey of Health, Ageing and Retirement in Europe, which included internationally harmonized information on over 50,000 individuals across 14 European countries, we calculated Gini and Concentration indices (CI) as well as the decompositions of CIs by socioeconomic factors.

Results

Sweden consistently performed the best with the lowest inequalities as measured by Gini (0.1078), CI by income (0.0392), CI by education (0.0407), and CI by wealth (0.0296). No country performed the worst in all inequality measures. However, unexpectedly, some wealthier countries (e.g., the Netherlands and Denmark) had higher degrees of inequalities than less-wealthy countries (e.g., Estonia and Slovenia). Decomposition analysis showed that income, education, and wealth contributed substantially to the inequalities, and dental service use was an important contributor even after controlling for income and wealth.

Conclusions

The study highlighted the importance of comprehensively investigating oral health inequalities. The results are informative to policymakers to derive country-specific health policy recommendations to reduce oral health inequalities in the older population and also have implications for oral health improvement of the future generations.
  相似文献   
998.
This study examines disparities in subjective well-being (SWB) among older migrants and natives across several European countries using data from the Survey of Health, Aging and Retirement in Europe (SHARE). Our results show a significant SWB gap between migrants and non-migrants that diminishes with increasing age. While migrants from Northern and Central Europe have similar SWB levels as natives, Southern European, Eastern European, and Non-European migrants have significantly lower levels of SWB than the native population. The immigrant-native gap becomes smaller but remains significant after controlling for sociodemographic characteristics and health, the financial situation, citizenship, age at migration, and length of residence. Additionally, we find that the size of the SWB gap varies largely across countries. Current family reunion policies as measured by the Migrant Integration Policy Index (MIPEX) correlate with these country differences. The immigrant-native gap is bigger in countries with restrictive and smaller in countries with open policies.  相似文献   
999.
The well-established a priori probability of illness threshold in medical decision making, introduced by Pauker and Kassirer (N Engl J Med 293:229–234, 1975; N Engl J Med 302:1109–1117, 1980), involves the diagnostic risk only. We generalize the threshold analysis by adding the therapeutic risk, i.e., in accounting for the risk that a treatment might sometimes fail. We derive a priori probability of illness threshold as a function of the probability of successful treatment, as well as the inverted function, where the successful treatment probability threshold is a function of the a priori probability of illness. The thresholds in the general model are higher than those in the special cases where one of the two risks is absent. Applications show that the changes in the thresholds can be substantial. Our general model might explain empirical findings of much higher thresholds than the Pauker–Kassirer model suggests.  相似文献   
1000.

Purpose

The aim of this study is to examine the prevalence and correlates of perceived health care stigma among female sex workers (FSWs) and men who have sex with men (MSM), including other stigma types, suicidal ideation, and participation in social activities.

Methods

FSWs (N = 350) and MSM (N = 330) aged ≥18 were recruited in Bobo-Dioulasso, Burkina Faso. Perceived health care stigma was defined as either ever being afraid of or avoiding health care services because someone might find out the participant has sex with men (for MSM) or sells sex (for FSW). Correlates of perceived health care stigma were examined using multivariable logistic regression.

Results

The prevalence of perceived health care stigma was 14.9% (52/350) and 24.5% (81/330) in FSWs and MSM, respectively. Among FSWs, experienced or social stigma, including verbal harassment (adjusted odds ratio [aOR] = 3.59, 95% confidence interval [CI] 1.48–8.71), feeling rejected by friends (aOR = 2.30, 95% CI 1.14–4.64), and feeling police refused to protect them (aOR = 2.58, 95% CI 1.27–5.25), was associated with perceived health care stigma. Among MSM, experiencing verbal harassment (aOR = 1.95, 95% CI 1.09–3.50) and feeling scared to walk in public (aOR = 2.93, 95% CI 1.47–5.86) were associated with perceived health care stigma.

Conclusions

In these key populations, perceived health care stigma was prevalent and associated with experienced and social stigmas. To increase coverage of effective HIV services, interventions should incorporate approaches to comprehensively mitigate stigma.  相似文献   
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