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181.
OBJECTIVES: To explore associated biological outcomes and clarify the role of timing of exposure in the alcohol-breast cancer relationship.METHODS: In a population-based study of 4,575 women ages 35 to 64 years diagnosed with invasive breast cancer between 1994 and 1998 and 4,682 controls, we collected details of lifetime alcohol use and factors that could confound or modify the alcohol-breast cancer relationship. We used conditional logistic regression to compute the odds of breast cancer among drinkers relative to nondrinkers at all ages and at ages 35 to 49 and 50 to 64 years separately.RESULTS: Recent consumption (at reference age minus two) of >/=7 drinks per week was associated with increased risk [odds ratio (OR), 1.2; 95% CI, 1.01-1.3] and evidence of dose response was observed. Most of the excess was observed among women ages 50-64 years (OR 1.3; 95% CI, 1.1-1.6), although the test for age interaction was not statistically significant. Exposure later in life seemed more important than early exposure. Excess breast cancer associated with recent consumption was restricted to localized disease. When outcome was examined according to tumor hormone receptor status, highest risks were observed for estrogen receptor-positive/progesterone receptor-negative tumors (OR 1.6; 95% CI, 1.2-2.3).CONCLUSIONS: The effect of timing of alcohol exposure on breast cancer risk is complicated and will require additional study focused on this one issue. Further work is needed to explain how alcohol exposure, sex hormones, and tumor receptor status interact.  相似文献   
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183.
Zusammenfassung Fragestellung: Die Diagnose des Williams-Beuren-Syndroms (WBS) wird durch die klinische Variabilit?t erschwert. Daher sollen der diagnostische Wert sowohl des von Preus aufgestellten klinischen Scores als auch der Elastingenhemizygotie geprüft und miteinander verglichen werden. Methodik: Bei 13 Kindern mit Verdacht auf WBS wurden der Preus-Score erhoben und eine Fluoreszenz-in situ-Hybridisierungs-Analyse des Elastingens sowie eine Chromosomenanalyse durchgeführt. Ergebnisse: Neun der 13 Patienten zeigten eine Deletion eines Elastingens bei normalem Karyotyp. Zwei Patienten wiesen bei normaler Elastingendosis eine Chromosomenaberration auf. Der Preus-Score lag bei allen Patienten mit Elastindeletion >6 und war damit hoch positiv. Bei den übrigen Kindern wurde ein Preus-Score von 0,18; 0,37, 1,00 und 6,4 ermittelt. Schlu?folgerung: Bei allen Patienten mit WBS lagen in dieser Studie eine Elastingendeletion und ein hoch positiver Preus-Score vor. Ein positiver Preus-Score wurde jedoch auch bei Patienten mit Chromosomenaberrationen ermittelt. Unter Berücksichtigung dieser Ergebnisse und der Daten aus der Literatur sollte daher die Diagnose Wiliams-Beuren-Syndrom nur unter Vorbehalt gestellt werden, wenn keine Elastingendeletion nachweisbar ist. Da aber bisher unbekannte Mutationen bei den wenigen Patienten ohne Elastingendeletion denkbar sind, kann ein WBS auf molekularer Ebene nicht mit letzter Sicherheit ausgeschlossen werden. Bei diesen Patienten k?nnte der Preus-Score zur klinischen Diagnose beitragen. Setzt man für die Diagnose eines WBS im Preus-Score einen Endsummenwert von >1 voraus, so wird eine Sensitivit?t von 100% bei einer Spezifit?t von 92% erreicht.   相似文献   
184.
Otoendoscopy enables viewing of different angles of the tympanomastoid area and approach to them for better prognosis. A comparative study of post-operative mastoid cavities has been done using the Hopkin’s rod telescope, Otoscope and microscope. Various procedures have also been done successfully on the mastoid cavity using the telescope on an outdoor basis.  相似文献   
185.
A series of 14 parapharyngeal tumours has been studied with regard to their symptology, pre-operative evaluation and surgical management. High resolution computed tomography is now the best initial diagnostic study because it helps to determine the size and extent of the tumour, differentiate tumours of parotid and extraparotid origin, demonstrate degree of tumour vascularity, separate benign from malignant lesions, plan the surgical approach and predict prognosis.  相似文献   
186.
A 23 years old male presented with a soft cystic mass in the left paralaryngeal space since 3 months. Indirect laryngoscopy revealed a bulging of the left lateral pharyngeal wall. Histopathologic al examination of the biopsy proved it to be a synovial sarcoma. The case is the seventh case reported in literature.  相似文献   
187.
Bias in questionnaires is an important issue in public health research. To collect the most accurate data from respondents, investigators must understand and be able to prevent or at least minimize bias in the design of their questionnaires. This paper identifies and categorizes 48 types of bias in questionnaires based on a review of the literature and offers an example of each type. The types are categorized according to three main sources of bias: the way a question is designed, the way the questionnaire as a whole is designed, and how the questionnaire is administered. This paper is intended to help investigators in public health understand the mechanism and dynamics of problems in questionnaire design and to provide a checklist for identifying potential bias in a questionnaire before it is administered.  相似文献   
188.
Measurement Issues in Health Disparities Research   总被引:3,自引:0,他引:3       下载免费PDF全文
Background. Racial and ethnic disparities in health and health care have been documented; the elimination of such disparities is currently part of a national agenda. In order to meet this national objective, it is necessary that measures identify accurately the true prevalence of the construct of interest across diverse groups. Measurement error might lead to biased results, e.g., estimates of prevalence, magnitude of risks, and differences in mean scores. Addressing measurement issues in the assessment of health status may contribute to a better understanding of health issues in cross-cultural research.
Objective. To provide a brief overview of issues regarding measurement in diverse populations.
Findings. Approaches used to assess the magnitude and nature of bias in measures when applied to diverse groups include qualitative analyses, classic psychometric studies, as well as more modern psychometric methods. These approaches should be applied sequentially, and/or iteratively during the development of measures.
Conclusions. Investigators performing comparative studies face the challenge of addressing measurement equivalence, crucial for obtaining accurate results in cross-cultural comparisons.  相似文献   
189.
BACKGROUND: Drug-drug interactions (DDIs) are a well known risk factor for adverse drug reactions. HMG-CoA reductase inhibitors ('statins') are a cornerstone in the treatment of dyslipidaemia and patients with dyslipidaemia are concomitantly treated with a variety of additional drugs. Since DDIs are associated with adverse reactions, we performed a cross-sectional study to assess the prevalence of potentially critical drug-drug and drug-statin interactions in an outpatient adult population with dyslipidaemia. METHODS: Data from patients with dyslipidaemia treated with a statin were collected from 242 practitioners from different parts of Switzerland. The medication list was screened for potentially harmful DDIs with statins or other drugs using an interactive electronic drug interaction program. RESULTS: We included 2742 ambulatory statin-treated patients (mean age +/- SD 65.1 +/- 11.1 years; 61.6% males) with (mean +/- SD) 3.2 +/- 1.6 diagnoses and 4.9 +/- 2.4 drugs prescribed. Of those, 190 patients (6.9%) had a total of 198 potentially harmful drug-statin interactions. Interacting drugs were fibrates or nicotinic acid (9.5% of patients with drug-statin interactions), cytochrome P450 (CYP) 3A4 inhibitors (70.5%), digoxin (22.6%) or ciclosporin (cyclosporine) [1.6%]. The proportion of patients with a potential drug-statin interaction was 12.1% for simvastatin, 10.0% for atorvastatin, 3.8% for fluvastatin and 0.3% for pravastatin. Additionally, the program identified 393 potentially critical non-statin DDIs in 288 patients. CONCLUSIONS: CYP3A4 inhibitors are the most frequent cause of potential drug interactions with statins. As the risk for developing rhabdomyolysis is increased in patients with drug-statin interactions, clinicians should be aware of the most frequently observed drug-statin interactions and how these interactions can be avoided.  相似文献   
190.
PURPOSE: Consumer assessments of interpersonal processes of care during prenatal care provide important information about how well clinicians satisfy the perceived needs of the women they serve, but few measures are available that tap the various components of these processes. The purpose of this study is to develop a multidimensional measure of prenatal interpersonal processes of care (PIPC) that demonstrates reliability and validity in ethnically diverse women in Medicaid managed care plans. METHODS: A telephone survey of African American, Latino (U.S. and foreign born) and Caucasian pregnant women in four Medicaid managed care plans in California was conducted in English and Spanish in 2001. Factor analytic methods were used to test the PIPC measures. A psychometric evaluation, including reliability, variability, and construct validity, was conducted with the final scales for the total sample and for each racial/ethnic group. RESULTS: Three dimensions, Communication, Patient-Centered Decision Making, and Interpersonal Style, with seven scales were supported with 30 items. The scales for each dimension exhibit acceptable reliability for the total sample (Internal Consistency Reliability ranged from 0.66 to 0.85) and for all racial/ethnic groups. All scales had significant associations with satisfaction with prenatal care and explained considerable variation in satisfaction (19-43%). The scale qualities and validity associations held for all scales and ethnic groups except some scales for U.S.-born Latinas. CONCLUSIONS: The multidimensional PIPC measure for assessing what actually happens between providers and low-income pregnant women of diverse ethnic groups demonstrates acceptable reliability and construct validity.  相似文献   
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