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671.
Dietary patterns are a set of habits regarding consumption of foods and beverages. They are often influenced by environmental or cultural particularities, and by religion. Examples of dietary patterns include the Mediterranean, Asian and Western diets, and the prudent diet. The majority of these dietary patterns suggest portion sizes for different food items, as well as giving information on the number of servings from each food group to be consumed on a daily, weekly or monthly basis. In the past, many epidemiological studies assessing the role that diet plays in health have focused upon single nutrients or food items. However, people do not eat isolated nutrients; instead they consume meals consisting of a variety of foods, with complex combinations of micro‐ and macronutrients. Therefore, it is becoming apparent that dietary pattern analysis may be a useful tool to use in research of this nature. In this review, two methodologies used to assess dietary patterns are described: α‐posterior and α‐priori pattern analysis.  相似文献   
672.
Background Obesity and diabetes are metabolic disorders that affect a large amount of the elderly population and are related to increased cardiovascular risk. Tea intake has been associated with lower risk of mortality and morbidity in some, but not all studies. We evaluated the association between tea intake, blood glucose levels, in a sample of elderly adults. Methods During 2005–2006, 300 men and women from Cyprus, 142 from Mitilini and 100 from Samothraki islands (aged 65–100 years) were enrolled. Dietary habits (including tea consumption) were assessed through a food frequency questionnaire. Among various factors, fasting blood glucose and body mass index (BMI) were measured. Results Fifty-four percent of the participants reported that they consume tea at least once a week (mean intake 1.6 ± 1.1 cup/day). A significant interaction was observed between tea intake, obesity status on glucose levels (P < 0.001). After adjusting for various confounders, tea intake was associated with lower blood glucose levels in non-obese (P for trend <0.001), but not in obese people (P = 0.24). Multiple logistic regression analysis revealed that moderate tea consumption (1–2 cups/day) was associated with 88% (95% CI 76–98%) lower odds of having diabetes among non-obese participants, irrespective of age, sex, smoking, physical activity status, dietary habits and other clinical characteristics. Conclusion Tea consumption is associated with reduced levels of fasting blood glucose only among non-obese elderly people.  相似文献   
673.
Mannose is the predominant monosaccharide in the coccidioidal antigen preparation T27K. Mannan and anti-CD206 antibody significantly decreased the surface expression of mannose receptor (MR) on adherent peripheral blood mononuclear cells and reduced the interleukin-2 (IL-2) release induced by T27K. These data suggest that MR mediates IL-2 release by T27K.  相似文献   
674.
Assessment of the cellular immune response in coccidioidomycosis has epidemiologic and prognostic importance. Measurement of delayed-type hypersensitivity to skin testing has been used in the past to determine cellular immunity in coccidioidomycosis. However, no skin tests are currently available in the United States. Assay of gamma interferon (IFN-γ) release in whole blood in response to incubation with antigen has been used to assess cellular immunity in tuberculosis. We used a similar assay using the coccidioidal antigen preparation T27K to measure the in vitro cellular immune responses among a cohort of 69 subjects with active coccidioidomycosis. IFN-γ release was bimodal, with concentrations above and below 5 IU/ml. Using multivariate logistic regression, underlying disease and disseminated or chronic pulmonary coccidioidomycosis was significantly associated with the release of IFN-γ at a concentration of <5 IU/ml (P = 0.02 or 0.05, respectively). In addition, the release IFN-γ concentration was <5 IU/ml in all subjects with a clinical severity score of ≥6 (P = 0.02). The release IFN-γ concentration correlated with expression of CD69 on T lymphocytes in an in vitro assay using T27K as the antigen (Spearman's rho = 0.59; P < 0.01). These results suggest that the IFN-γ release assay with T27K as the antigen may be a useful clinical test for assessing cellular immunity in patients with active coccidioidomycosis.  相似文献   
675.
Prognostic value of serum tumor markers in patients with lung cancer   总被引:22,自引:0,他引:22  
BACKGROUND: The role of tumor markers in the diagnosis and prognosis of lung cancer is under investigation. OBJECTIVES: The aim of this study was to investigate the diagnostic and prognostic significance of pre-therapeutic levels of various serum tumor markers, CYFRA 21-1, neuron-specific enolase (NSE), tissue polypeptide antigen (TPA), carcinoembryonic antigen (CEA), CA 125 and squamous cell carcinoma antigen (SCCAg), in patients with lung cancer. METHODS: We studied 102 consecutive patients (mean age 65.2 +/- 11 years) with newly diagnosed lung cancer (96 males, 94%, with a mean age of 66.3 +/-10.5 years). All patients had a 5-year follow-up. Measurements of the serum tumor markers were performed on initial diagnosis. RESULTS: Eighty-four patients (82%) had non-small-cell lung cancer (NSCLC) and 18 (18%) small-cell lung cancer (SCLC). From the 84 patients with NSCLC, 34 patients (33%) had squamous-cell lung cancer, 23 (22%) adenocarcinoma and 23 (22%) large-cell carcinomas. The overall median survival was 8.5 months. All SCLC patients had extensive disease with a median survival of 10.1 months and NSCLC patients of 8.4 months. Significant differences in the mean values of NSE and CYFRA 21-1 were observed between SCLC and NSCLC. In NSCLC, CYFRA 21-1, TPA, CA 125 and SCCAg serum levels were related to the stage of the disease at diagnosis, and CYFRA 21-1, NSE, TPA and CA-125 were related to a poor outcome. None of the above tumor markers was related to survival in the SCLC group. CONCLUSION: CYFRA 21-1 and NSE may help to differentiate cell types in lung cancer patients. Also, CYFRA 21-1 with TPA and CA 125 may provide useful information regarding the staging of the disease at diagnosis and the prognosis of patients with NSCLC.  相似文献   
676.
BACKGROUND: Detailed right and left septal mapping of retrograde atrial activation during typical atrioventricular nodal reentrant tachycardia (AVNRT) has not been undertaken and may provide insight into the complex physiology of AVNRT, especially the anatomic localization of the fast and slow pathways. OBJECTIVES: The purpose of this study was to investigate the pattern of retrograde atrial activation during typical AVNRT by means of right-sided and left-sided septal mapping and implementation of pacing maneuvers for separating atrial and ventricular electrograms recorded during tachycardia. METHODS: Twenty-two patients with slow-fast AVNRT were studied by means of simultaneous His-bundle recordings from the right and left sides of the septum. Patterns of retrograde atrial activation were recorded during tachycardia following specific pacing maneuvers and during right ventricular apical (RVA) pacing at the tachycardia cycle length. RESULTS: The pattern of retrograde atrial activation could be mapped in 17 of 22 patients during AVNRT. In 9 (53%) patients, the earliest retrograde atrial activation was recorded on the left side of the septum, in 3 (17%) patients on the right side, and in 5 (29%) patients both right and left atrial septal electrograms occurred simultaneously. Stimulus to atrial electrogram times recorded during RVA pacing in 14 patients were 138.5 ms from the right His bundle, 134.5 ms from the left His bundle, and 148.0 ms from the ostium of the coronary sinus (P <.001). The predominant site of earliest retrograde atrial activation during RVA pacing was the left side of the septum (10 patients [71%]). Only 8 (57%) of 14 patients demonstrated concordance in the pattern of retrograde atrial activation during AVNRT and RVA pacing. CONCLUSION: Earliest retrograde atrial activation during AVNRT is most often recorded on the left side of the septum. Breakthrough of atrial activation may be discordant from that observed during RVA pacing.  相似文献   
677.
The World Health Organization reports that the number of hypertensives, worldwide, is estimated to be 600 million people. In addition a considerable proportion of hypertensive subjects remains untreated or uncontrolled. In this work we investigated the combined effect of physical activity and Mediterranean diet on coronary risk, in hypertensives. Thus we randomly selected, from all Greek regions, 848 hospitalised patients (695 males, 58 +/- 10 years old and 153 females, 65 +/- 9 years old) with a first event of coronary heart disease (CHD) and 1078 paired, by sex, age, region controls, without any suspicions for CHD. Physically active were those who reported non-occupational physical activity more than once per week. Subjects 'closer' to the Mediterranean diet were assessed through a special nutrient questionnaire. A total of 418 (49%) of the patients and 303 (28%) of the controls were hypertensive. Of these, 115 (27%) patients and 70 (23%) controls were untreated, 148 (35%)-111 (36%) were uncontrolled and 155 (38%)-122 (41%) were controlled (P-value <0.01). One hundred and sixty-two (19%) of the patients and 265 (25%) of the controls (P < 0.01) were 'closer' to the combination of Mediterranean type of diet and physical activity. The analysis showed that the previous combination is related to a 25% reduction of the coronary risk in controlled hypertensive subjects (OR = 0.75, P < 0.01), a 11% reduction in untreated (OR = 0.89, P < 0.05) and 17% reduction (OR = 0.83, P < 0.05) in uncontrolled, after adjusting for age, sex, educational and financial level and the conventional cardiovascular risk factors. Consequently, the adoption of Mediterranean diet by physically active subjects seems to reduce significantly the coronary risk and prevent, approximately, the one-third of acute CHD, in controlled hypertensive subjects.  相似文献   
678.
AIMS: To investigate the prognostic significance and electrophysiological characteristics of dobutamine stress echo (DSE)-induced sustained monomorphic ventricular tachycardia (VT). METHODS: In our department, 3022 DSE studies were carried out on 2688 patients, aged 54.7 +/- 11.8 years, over a 3.5 year period. Patients with DSE-induced VT were studied by means of coronary angiography and electrophysiological testing, and were followed-up for 17.8 +/- 9.3 months. RESULTS: During DSE, nine patients (0.3%) developed sustained monomorphic VT. Four patients had coronary artery disease, one developed spontaneous right coronary artery (RCA) dissection during DSE, one patient had peripartum cardiomyopathy and the remainder had normal coronary arteries. Logistic regression analysis did not identify clinical parameters such as left ventricular ejection fraction, documentation of an ischaemic response or the presence of non-viable myocardial segments during DSE, that could predict the occurrence of DSE-induced VT. Monomorphic VT was inducible by electrophysiological testing in two patients with CAD and reduced LVEF. During follow-up, only these two patients developed VT. CONCLUSION: Sustained monomorphic VT is a rare complication of DSE, with no predictive value for the identification of patients with coronary artery disease and no prognostic significance in patients with normal coronary arteries. No predictors of its occurrence were identified.  相似文献   
679.
The gallbladder and bile ducts are usually assessed initially with conventional gray‐scale ultrasound (US). Contrast enhanced US (CEUS) is used when a diagnosis cannot be reached with conventional US. CEUS is easy to learn and perform. US contrast agents can be safely administered in patients with renal function impairment. In this pictorial essay the physics, examination technique and indications of CEUS for examining the gallbladder and bile ducts are reviewed. Gallbladder indications include elucidating normal variants, differentiating sludge from neoplastic lesions, benign and malignant pathology, infection, wall rupture and hemobilia. In the biliary tree CEUS is used for studying benign and malignant tumors, including metastases and cholangiocarcinoma, as well as intrabiliary injection.  相似文献   
680.

Background

We evaluated the effect of the point mutation of guanine to thymine at nucleotide position 894 (G894T) of the endothelial nitric oxide synthase (eNOS) gene on inflammatory and oxidative stress markers.

Methods

We studied genetic information from 270 men (18-87 years old) and 325 women (18-89 years old). Participants without any clinical evidence of cardiovascular or other atherosclerotic disease were randomly selected from the general population according to the age-sex distribution of Athens greater area. Genomic DNA was extracted from 2 to 5 mL of fresh or frozen whole blood using standard methods.

Results

The DNA analysis showed that 10.6% of the participants were Asp-homozygotes (Asp/Asp), 40% heterozygotes (Asp/Glu) and 49.4% Glu-homozygotes (Glu/Glu). Compared to Asp/Glu and Glu/Glu, Asp/Asp had higher levels of fibrinogen (332 ± 46 or 329 ± 33 vs 319 ± 29 mg/dL, P = .029), white blood cells (6.9 ± 0.6 or 6.5 ± 0.3 vs 6.1 ± 0.9 × 103 counts, P = .044), and oxidized low-density lipoprotein cholesterol (68 ± 21 or 61 ± 22 vs 59 ± 20 mg/dL, P = .039), after controlling for several potential confounders. An insignificant association was found between homocysteine (P = .08), C-reactive protein (P = .096), and the distribution of G894T polymorphism (P < .1). No association between the distribution of the polymorphism and hypertension status of the participants was observed.

Conclusions

Our results imply that G894T polymorphism of the endothelial nitric oxide synthase gene is associated with elevated levels of inflammatory and oxidative stress markers, which may partially explain the increased prevalence of G894T polymorphism among patients with cardiovascular disease.  相似文献   
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