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101.
This study examined the relationship between severe traumatic events and alcohol use disorders in American Indian adolescents and young adults. Interviews of 432 adolescents and young adults who were enrolled tribal members living on or near two closely related American Indian reservations were used. Results indicated that severe trauma increased the odds of alcohol use disorders (p <.001), with the number of traumas having a dose-dependent effect. The authors conclude that trauma is associated with alcohol use disorders in this population. This study's findings yield important insights into the risks in American Indian adolescents and young adults that may result from early trauma, as well as implications for the timing and possible settings for intervention.  相似文献   
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Prenatal diagnosis of fetal arrhythmias   总被引:2,自引:0,他引:2  
Life-threatening fetal arrhythmias are rare and warrant sophisticated specialty prenatal care, often provided by maternal-fetal medicine obstetricians, and pediatric and adult cardiologists. This medical field is in quick transition, and new methods of diagnosis and treatment of the fetus with arrhythmias are emerging. In this article, the mechanisms of arrhythmias are presented in light of recent progress in the new field of fetal electrophysiology. Treatments are reviewed with recommendations based on the small number of series of fetal tachycardia and fetal atrioventricular (AV) block drug treatment strategies published to date. Finally, a summary of areas of potential future research is provided.  相似文献   
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We describe modifications and improvements to our first report of a new nuclear emulsion coating technique for both light and electron microscopic autoradiography. Although this technique was originally designed to facilitate electron microscopic autoradiography, the methodology also allows pre-staining of plastic-embedded tissue sections prior to coating the slides with nuclear emulsion for light microscopic autoradiography. We now demonstrate that paraffin sections can be autoradiographically processed after being subjected to a combination of immunocytochemical reactions and special neuroanatomical stains. Parlodion film has been found to be more resistant to temperature changes and less prone to contamination than Formvar film. The shape of the double adhesive tape is an important aspect of the electron microscopic technique; it has been modified to minimize contamination and facilitate the removal of the grids from the glass slide. These technical adjustments facilitate the application of the nuclear emulsion and increase radionuclide specificity, thus expanding the investigative horizons of light and electron microscopic autoradiography.  相似文献   
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1. Severe persistent asthma is accompanied by structural changes in the airway, referred to as remodelling. The mechanisms driving airway remodelling are poorly understood. 2. Transforming growth factor (TGF)-beta is increased in the airways of patients with asthma. Many of the effects of TGF-beta are mediated by connective tissue growth factor (CTGF). 3. Overexpression of CTGF is linked to many fibrotic diseases, but its exact role in airway remodelling is unknown. 4. Connective tissue growth factor mediates cell adhesion, migration, proliferation, survival, extracellular matrix synthesis and has a role in angiogenesis. 5. Current asthma therapies do not inhibit CTGF induction. 6. Understanding the mechanisms underlying the role of CTGF in airway remodelling may lead to new therapeutic strategies for asthma.  相似文献   
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OBJECTIVE

We carried out a secondary analysis in high-risk patients with a previous myocardial infarction (MI) and diabetes in the Alpha Omega Trial. We tested the hypothesis that in these patients an increased intake of the n-3 fatty acids eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and α-linolenic acid (ALA) will reduce the incidence of ventricular arrhythmias and fatal MI.

RESEARCH DESIGN AND METHODS

A subgroup of 1,014 post-MI patients with diabetes aged 60–80 years was randomly allocated to receive one of four trial margarines, three with an additional amount of n-3 fatty acids and one placebo for 40 months. The end points were ventricular arrhythmia–related events and fatal MI. The data were analyzed according to the intention-to-treat principle, using multivariable Cox proportional hazards models.

RESULTS

The patients consumed on average 18.6 g of margarine per day, which resulted in an additional intake of 223 mg EPA plus 149 mg DHA and/or 1.9 g ALA in the active treatment groups. During follow-up, 29 patients developed a ventricular arrhythmia–related events and 27 had a fatal MI. Compared with placebo patients, the EPA-DHA plus ALA group experienced less ventricular arrhythmia–related events (hazard ratio 0.16; 95% CI 0.04–0.69). These n-3 fatty acids also reduced the combined end-point ventricular arrhythmia–related events and fatal MI (0.28; 0.11–0.71).

CONCLUSIONS

Our results suggest that low-dose supplementation of n-3 fatty acids exerts a protective effect against ventricular arrhythmia–related events in post-MI patients with diabetes.There is strong evidence from prospective cohort studies and randomized trials that >250 mg/day of the fish fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) will reduce fatal coronary heart disease (CHD) by as much as 36% (1). There is also evidence, although less conclusive, that EPA-DHA reduces sudden death (2,3). Prospective cohort studies have provided evidence that the plant food–derived n-3 fatty acid α-linolenic acid (ALA) may reduce fatal CHD (4). Animal experiments showed that n-3 fatty acids reduce the vulnerability to cardiac arrhythmias (5). The Alpha Omega Trial tested the hypothesis that an additional intake of 0.4 g/day of EPA-DHA or 1.9 g/day of ALA will reduce fatal CHD and ventricular arrhythmia–related events in stable postmyocardial infarction (post-MI) patients (6). However, this hypothesis was not confirmed in the main analysis of the trial (7).A post hoc analysis of the Alpha Omega Trial showed that in post-MI patients with diabetes, EPA-DHA reduced both fatal CHD and ventricular arrhythmia–related events by 49% (7). The reduction in these end points was in accord with that obtained in the Gruppo Italiano per lo Studio della Sopravvivenza nell''Infarto miocardico (GISSI)-Prevenzione trial for fatal coronary and sudden death (8). In the Alpha Omega Trial, an even stronger reduction of 61% of ventricular arrhythmia–related events was observed for ALA. This evokes the question of whether post-MI patients with diabetes are particularly susceptible to protective effects of n-3 fatty acids on fatal CHD and ventricular arrhythmia–related events.In a cohort study of diabetic women, a dose-response relation was observed between fish consumption and CHD mortality (9). Women who consumed fish five or more times per week had a 64% lower risk of CHD mortality compared with those who consumed fish less than once per month. In a trial of heart failure patients with diabetes, a supplement of 0.9 g EPA-DHA per day reduced the composite end point of all-cause mortality or admission to the hospital for cardiovascular reasons significantly with 11% (10). Although evidence of the effect of fish consumption and EPA-DHA supplementation on fatal CHD in patients with diabetes is small, the available data are compatible with the hypothesis that EPA-DHA may protect against fatal CHD.The life expectancy of a 50-year-old patient with diabetes is 6 years shorter than that of a person without diabetes (11). This difference is largely due to an increased risk of macrovascular diseases among diabetic patients. In addition, they have an increased risk of fatal CHD (12) and an increased risk of sudden death (13,14). A previous MI in combination with diabetes especially makes patients prone to fatal CHD and ventricular arrhythmia–related sudden death (12,15). Therefore, post-MI patients with diabetes are a suitable group to test the hypothesis that n-3 fatty acids protect against fatal CHD and ventricular arrhythmia–related events.Overlap in the definitions of ventricular arrhythmia–related events and in fatal CHD was present in the main publication of the results of the Alpha Omega Trial (7). Both end points included fatal cardiac arrest and sudden death. In the present analysis, mutually exclusive definitions will be used; therefore, fatal CHD is limited to fatal MI. In the main publication, the two groups that received EPA-DHA were compared with the two groups that did not receive EPA-DHA. The same strategy was used for ALA. This was done because in the analysis of the primary end-point major cardiovascular events, the cumulative incidence of the four treatment groups did not differ. Here we present the results of an in-depth analysis of the effects of different n-3 fatty acids compared with placebo on ventricular arrhythmia–related events and fatal MI in stable post-MI patients with diabetes.  相似文献   
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