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991.
BACKGROUND: Few epidemiologic studies of dietary fiber intake and risk of coronary heart disease have compared fiber types (cereal, fruit, and vegetable) or included sex-specific results. The purpose of this study was to conduct a pooled analysis of dietary fiber and its subtypes and risk of coronary heart disease. METHODS: We analyzed the original data from 10 prospective cohort studies from the United States and Europe to estimate the association between dietary fiber intake and the risk of coronary heart disease. RESULTS: Over 6 to 10 years of follow-up, 5249 incident total coronary cases and 2011 coronary deaths occurred among 91058 men and 245186 women. After adjustment for demographics, body mass index, and lifestyle factors, each 10-g/d increment of energy-adjusted and measurement error-corrected total dietary fiber was associated with a 14% (relative risk [RR], 0.86; 95% confidence interval [CI], 0.78-0.96) decrease in risk of all coronary events and a 27% (RR, 0.73; 95% CI, 0.61-0.87) decrease in risk of coronary death. For cereal, fruit, and vegetable fiber intake (not error corrected), RRs corresponding to 10-g/d increments were 0.90 (95% CI, 0.77-1.07), 0.84 (95% CI, 0.70-0.99), and 1.00 (95% CI, 0.88-1.13), respectively, for all coronary events and 0.75 (95% CI, 0.63-0.91), 0.70 (95% CI, 0.55-0.89), and 1.00 (95% CI, 0.82-1.23), respectively, for deaths. Results were similar for men and women. CONCLUSION: Consumption of dietary fiber from cereals and fruits is inversely associated with risk of coronary heart disease.  相似文献   
992.
We investigated whether changes in iron metabolism and the transferrin receptor (TRF-R) expression were involved in the antileukaemic effects of arabinoside cytosine (ara-C). Treatment with 100 n M ara-C for 48 h reduced thymidine uptake and increased the surface expression of the TRF-R on leukaemic blasts derived from 13/16 (81%) patients and on the HL-60 and U-937 cell lines. Whereas intracellular non-haem iron was strongly depleted 24 h after ara-C addition, TRF-R up-regulation and recovery of intracellular non-haem iron concentration occurred together after a longer exposure of the cultured cells to the drug. Since iron is an essential regulator of cell proliferation we have evaluated the effects of the combination between ara-C and the iron chelator desferioxamine (DSF) on the growth of HL-60 and U-937 cells. We found that desferioxamine strongly potentiated the effects of ara-C on leukaemic cell growth inhibition and apoptosis. This is the first report of a positive interaction between ara-C and an iron chelator in terms of antileukaemic effects.  相似文献   
993.
994.
Introduction and objectivesAsian desert dust has recently been recognized as a trigger for acute myocardial infarction. The inflow of dust from the Sahara into Spain impairs air quality due to an increase in particulate matter concentrations in the ambient air. The aim of the present study was to elucidate whether Saharan dust events are associated with the incidence of acute coronary syndrome (ACS) in patients living near North Africa, the major global dust source.MethodsWe prospectively collected data on hospitalizations due to ACS in 2416 consecutive patients from a tertiary care hospital (Canary Islands, Spain) from December 2012 to December 2017. Concentrations of particulate matter with an aerodynamic diameter 10 microns or smaller (PM10) and reactive gases were measured in the European Air Quality Network implemented in the Canary Islands. We applied the time-stratified case crossover design using conditional Poisson regression models to estimate the impact of PM10 Saharan dust events on the incidence of ACS.ResultsThe occurrence of Saharan dust events observed 0 to 5 days before the onset of ACS was not significantly associated with the incidence of ACS. Incidence rate ratios (IRR) of PM10 levels 1, 2, 3, 4 and 5 days before ACS onset (for changes in 10 μg/m3) were 1.27 (95%CI, 0.87-1.85), 0.92 (95%CI, 0.84-1.01), 0.74 (95%CI, 0.45-1.22), 0.98 (95%CI, 0.87-1.11), and 0.95 (95%CI, 0.84-1.06), respectively.ConclusionsExposure to Saharan desert dust is unlikely to be associated with the incidence of ACS.  相似文献   
995.
Summary The effect of somatostatin on the course and severity of experimental pancreatitis was tested. Acute pancreatitis was induced in 210 Sprague-Dawely rats by injecting a 4.3% sodium taurocholate solution, saturated with trypsin, into a temporarily closed duodenal loop. Immediately after the end of the surgical procedure somatostatin or, alternatively, normal saline were administered as a bolus followed by continuous subcutaneous infusion for 9 h. Ninety rats (30 untreated, 30 saline-treated and 30 somatostatin-treated) were sacrificed 10 h after the induction of pancreatitis to assess the histologic severity of pancreatic lesions, the amount of peritoneal exudate and the circulating levels of amylase. In another 120 rats (40 untreated, 40 saline-treated and 40 drug-treated) the mortality rate was evaluated so that the histologic examination of the pancreas followed spontaneous death. In sacrificed animals somatostatin treatment lowered serum amylase levels and definitely improved pancreatic histopathology (edema, leucocyte infiltration and necrosis). The drug prevented the occurrence of severe necrosis in all treated animals. Somatostatin did not affect the mortality rate of pancreatitic rats (70%) although post-mortem histologic examination revealed significantly less pancreatic histopathology in drug-treated rats than in their controls.  相似文献   
996.
We report a case of benign idiopathic retroperitoneal fibrosis in a 39-year-old male, who was successfully treated with immunosuppressive drugs only. Advances in imaging techniques, especially in magnetic resonance imaging, often permit an accurate diagnosis in retroperitoneal fibrosis, avoiding open biopsy or biopsy by means of image-guided techniques. In addition, the modern medical approach with immunosuppressive drugs is based on evidence of disease regression following the medical therapy and is frequently effective. Hence, it is possible to avoid conventional surgery or laparoscopy. In the present case the response to immunosuppressive treatment was objectively assessed by means of enhanced computed tomography, magnetic resonance and nuclear medicine (Ga-67), showing an important decrease in the extent of the disease at follow-up. Our case shows the important role of the specialist in Internal Medicine in the treatment of this uncommon connective tissue disease.  相似文献   
997.
Transcatheter valvulotomy in pulmonary atresia with an intact ventricular septum can be used as a first step to create biventricular circulation and to stimulate further development of the hypoplastic right ventricle. We describe our experience in a case of a neonate with this congenital cardiac defect who underwent successful transcatheter perforation of the atretic pulmonary valve. This report highlights the utility of a special technique based on the use of a gooseneck snare positioned just above the atretic valve to guide the advance of a coronary guidewire. Other therapeutic alternatives are considered.  相似文献   
998.

Introduction and objectives

Multidetector computed tomography (MDCT) has been demonstrated as a feasible alternative to invasive coronary angiography (ICA). However, contradictory results have been reported regarding the effect of coronary artery calcium score (CS) on the diagnostic accuracy of MDCT. Our aim was to assess the agreement of MDCT and ICA and to evaluate the influence of CS on this agreement.

Methods

We enrolled 266 consecutive patients who underwent evaluation with 64-slice MDCT and ICA. Standard CS software tools were used to calculate the Agatston score. Stenosis was qualitatively classified as mild, moderate, or severe by 1 blinded observer and the results were compared with those of ICA, which was used as the gold standard.

Results

The mean age of the patients was 65.4 ± 11.2 years, and 188 patients (70.3%) were men. A total of 484 segments with coronary stenosis ≥ mild were qualitatively evaluated and quantified with MDCT. Noninvasive measurements were concordant with ICA in 402 stenoses (83.05%; Kappa, 0.684), with no significant differences between vessels and with no statistically significant influence of CS on this agreement (OR, 0.93; 95%CI, 0.76-1.09; P = .21). Multidetector computed tomography had high sensitivity, specificity, positive predictive value, and negative predictive value on a per-segment, per-vessel, and per-patient basis.

Conclusions

Non-ICA using MDCT showed good agreement with ICA in the qualitative quantification coronary stenosis and CS had no significant impact on this agreement.Full English text available from: www.revespcardiol.org/en  相似文献   
999.
The blood-feeding behaviour of nymphs and adults of Triatoma brasiliensis fed on the forearm of human volunteers was studied by electronic monitoring of the cibarial pump. Parameters of total contact time (TT), initial weight (IW), weight gain (WG), ingestion rate (IR), pump frequency (F), quantity of liquid ingested per cibarial pump stroke (QLC) and non-ingestive time (NIT) (cumulative probing time and pumping interruptions during blood feeding) were measured. Protein profile (SDS-PAGE) and quantity of proteins of salivary gland extracts (QP) were also determined for each stage. The TT reflects the feeding performance of the insects and differed between instars, varying between 18.3+/-2.5 min for the first instar and 33.9+/-2.3 min for the fifth instar. The observed increase in the IR when comparing different instars was related to the increase in the cibarial pump volume inferred from the QLC data. During development, the volume of the cibarial pump grew asymmetrically determining the different contact times observed among the instars. Males and females presented a remarkable sexual dimorphism in respect to the volume of the cibarial pump, females showing a better performance compared to males. Despite the differences, the results show that each of the development stages of T. brasiliensis was able to obtain a relatively fast bloodmeal, with few interruptions and without causing pain, providing further evidence of the capacity of this species to adapt to domestic environments.  相似文献   
1000.
INTRODUCTION AND OBJECTIVES: The acute inflammatory response is an important phenomenon in the pathogenesis of myocardial damage during acute coronary syndrome. Endothelial dysfunction has been found in unstable angina and acute myocardial infarction, although the results are controversial. The purpose of this study was to determine the levels of the soluble endothelial adhesion molecules ICAM-1, VCAM-1 and E-selectin, in patients with unstable angina and acute myocardial infarction, compare the results in both groups, and analyze their relation with the degree of myocardial injury. METHODS: Serum concentrations of ICAM-1, VCAM-1, and E-selectin were measured in 37 control subjects and 43 patients (32 with acute myocardial infarction and 11 with unstable angina). Measurements were made at the time of admission and ten days later using commercial enzyme-linked immunoabsorbent assay (ELISA) kits (R&D Systems, UK). RESULTS: There was a significant increase in E-selectin (p < 0.05) in patients with unstable angina at admission and ten days later. In contrast, patients with acute myocardial infarction showed no significant differences in E-selectin compared with the control group at admission or ten days later. A significant increase in VCAM-1 levels was demonstrated in both groups of patients and ICAM-1 levels in acute myocardial infarction, but the concentrations of VCAM-1 and ICAM-1 in both groups of patients at admission and ten days later did not differ significantly. There was no relation between soluble endothelial adhesion molecule levels and the severity of myocardial damage estimated by cardiac enzymes or electrocardiographic changes. CONCLUSION: This study indicates that serum levels of E-selectin, measured at time of admission and ten days later, could be a marker for unstable angina and might be useful in the differential diagnosis with myocardial infarction.  相似文献   
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