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81.
BACKGROUND: Premenopausal African American women have a 2-3 times greater incidence of coronary heart disease (CHD) than do white women. The plasma lipid responsiveness to dietary fat, which may be associated with CHD, has not been adequately studied in premenopausal African American or white women. OBJECTIVE: The objective of our study was to compare the effect of diet on fasting plasma lipids and lipoproteins and postprandial lipemia in premenopausal African American and white women. DESIGN: Thirteen African American and 9 white healthy premenopausal women were fed a low-fat, high-fiber diet and a high-fat, low-fiber diet for 4 wk each in a randomized crossover design. Fasting plasma lipid and lipoprotein concentrations and the 24-h plasma triacylglycerol response to a standard fatty test meal were measured at the end of each dietary period. RESULTS: Plasma total and LDL-cholesterol concentrations were higher after the high-fat, low-fiber diet in both white and African American women (P < 0.0001). The 24-h area under the plasma triacylglycerol curve after the test meal was lower after the low-fat diet than after the high-fat diet (P < 0.04). CONCLUSIONS: African American and white women had lower fasting plasma total and LDL-cholesterol concentrations and less postprandial lipemia after the low-fat than the high-fat diet. Diets low in total and saturated fat and cholesterol and high in fiber may reduce the risk of CHD by lowering fasting plasma total and LDL-cholesterol concentrations and by reducing the lipemic response to fatty meals.  相似文献   
82.

Background  

Injecting drug users represent a high risk group for hepatitis C (HCV) infection. Currently, screening of this group for HCV is inconsistently implemented.  相似文献   
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85.
The aim of this study was to describe the clinico-radiological correlations of magnetic resonance (MR) perfusion and diffusion-weighted imaging (DWI) abnormalities in ischemic stroke. Eighteen patients had undergone MR imaging and clinical evaluation within 24 h of symptom onset and at or after 7 days. During the first 24 h the volume of perfusion abnormality (measured on the relative mean transit time map) was larger than the DWI lesion in 12/18 patients. In 6/18 patients the DWI lesion volume was larger. Acutely (<24 h) all lesion volumes showed a significant correlation with acute clinical severity measured by the National Institutes of Health Stroke Scale score. The correlations of the hypoperfusion volume (rho = 0.86, p = 0.0001) and the volume 'tissue at risk' (larger than the DWI and perfusion lesion volumes, rho = 0.86, p = 0. 0001) with acute clinical severity were slightly higher than for the DWI lesion volume (rho = 0.76, p = 0.0001). The difference between the volume of tissue at risk (acutely) and the infarct on follow-up T(2)-weighted imaging correlated significantly with change in clinical severity from acute to chronic time points (rho = 0.72, p = 0.001). Such clinico-radiological relationships may support the use of DWI and perfusion MR in decisions concerning the administration and evaluation of stroke therapies.  相似文献   
86.
BACKGROUND: Recent evidence implicates nitric oxide (*NO) in the pathogenesis of preeclampsia. The authors tested the hypothesis that administration of low-dose endotoxin to pregnant rats mimics the signs of preeclampsia in humans and that *NO and *NO-derived species play a role in that animal model. METHODS: Endotoxin was infused at doses of 1, 2 and 10 microg/kg over 1 h to rats on day 14 of pregnancy. Mean arterial pressure, urinary protein, urinary and plasma nitrite plus nitrate (NO2- + NO3-) concentrations, and platelet count were measured before and after the endotoxin infusion. In another group of pregnant rats, the nitric oxide synthase inhibitor L-nitroarginine methyl ester (L-NAME) was administered in drinking water at a dose of 3 mg x kg(-1) x d(-1) starting on day 7 of pregnancy. Endotoxin was then infused at 10 microg/kg on day 14 of pregnancy. Kidneys and uteroplacental units were examined histologically and analyzed immunohistochemically for 3-nitrotyrosine. RESULTS: Endotoxin administration at doses of 2 and 10 microg/kg caused proteinuria and thrombocytopenia in pregnant rats, but did not result in hypertension. Urinary NO2- + NO3- concentration, reflective of tissue *NO production rates, was significantly elevated in pregnant rats that received endotoxin at 10 microg/kg. Ingestion of L-NAME caused hypertension. Tissues from pregnant rats treated with L-NAME, endotoxin at 10 microg/kg, and a combination of L-NAME and endotoxin had increased 3-nitrotyrosine immunoreactivity. CONCLUSION: Nitric oxide either directly or through secondary species plays a significant role in the biochemical and physiologic changes that occur in a rodent model of endotoxin-induced injury.  相似文献   
87.
We investigated epidemiologic and molecular characteristics of healthcare-associated (HA) and community-associated (CA) Clostridioides difficile infection (CDI) among adult patients in Canadian Nosocomial Infection Surveillance Program hospitals during 2015–2019. The study encompassed 18,455 CDI cases, 13,735 (74.4%) HA and 4,720 (25.6%) CA. During 2015–2019, HA CDI rates decreased by 23.8%, whereas CA decreased by 18.8%. HA CDI was significantly associated with increased 30-day all-cause mortality as compared with CA CDI (p<0.01). Of 2,506 isolates analyzed, the most common ribotypes (RTs) were RT027, RT106, RT014, and RT020. RT027 was more often associated with CDI-attributable death than was non-RT027, regardless of acquisition type. Overall resistance C. difficile rates were similar for all drugs tested except moxifloxacin. Adult HA and CA CDI rates have declined, coinciding with changes in prevalence of RT027 and RT106. Infection prevention and control and continued national surveillance are integral to clarifying CDI epidemiology, investigation, and control.  相似文献   
88.
Haemoglobin (10 nM-30 microM) caused contraction of dog isolated basilar artery. In preparations which were perfused with Triton X-100 (0.1%) for one min to remove the endothelium, substance P relaxation was abolished but haemoglobin-induced contractions were unchanged. Endothelium removal or damage was confirmed histologically. These results suggest that the integrity of the endothelium is not essential for haemoglobin to produce contraction in dog basilar artery.  相似文献   
89.
Since 1983, social scientists have collaborated with teaching staff at the Faculty of Medicine, Udayana University, Bali, Indonesia, to develop an integrated sociocultural curriculum for undergraduate students in community health. The Udayana curriculum is discussed in the context of an international commitment over the last two decades to appropriate education for primary health care and community health in developing countries. The authors describe their work as consultants with Udayana staff. Participants formulated a five-stage project of curriculum development and community health research that could be continued as part of an ongoing community medicine teaching program. Recommendations for integrating social science perspectives within medical domains are outlined, based on the project experience. The paper also discusses the undertaking as a 'development project' suggesting that many of the issues and problems that arose are common to bureaucratic institutions in Third World countries when development projects are initiated.  相似文献   
90.
Underrepresentation of Black individuals in genetic research is a longstanding issue. There are well-documented strategies to improve the enrollment of Black participants; however, few studies explore these strategies—as well as the barriers and facilitators for participation—by sampling Black people who have previously participated in genetic research. This study explores the decision-making process of Black adults who have participated in genetic research to identify best practices in the recruitment of Black subjects in genetic research. We conducted 18 semi-structured interviews with Black adults with prior research participation in genetic studies housed at an urban academic medical center in the United States of America (USA). An online survey was conducted with the participants to gather demographic data and information on prior research participation. Trust in research was ascertained with the Corbie-Smith Distrust in Clinical Research Index. Two participants scored high levels of distrust using the validated index. Using thematic content analysis, 4 themes emerged from the interviews: (1) Participants are active players in health system, (2) information is power, and transparency is key, (3) therapeutic alliances and study characteristics facilitate participation, and (4) race pervades the research process. The decision to participate in genetic research for the participants in our study was prompted by participants’ internal motivations and facilitated by trust in their doctor, trust in the institution, and ease of participation. Most participants viewed their enrollment in genetic research in the context of their own racial identity and the history of medical racism in the USA.  相似文献   
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