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941.
942.
INTRODUCTION: We reviewed our experience in managing intracardiac ultrasound-detected left atrial thrombus and analyzed the impact of the timing of heparin therapy on thrombus incidence. METHODS AND RESULTS: We identified 508 patients undergoing ablation procedures for atrial fibrillation in which intracardiac ultrasound was used. All patients received unfractionated heparin during the procedure: 31 patients before the first transseptal puncture (preTS1), 257 between the first and second transseptal punctures (TS1-TS2), and 220 following both punctures (postTS2). By using intracardiac echocardiography (ICE), thrombus was detected in 30 of these 508 patients (5.9%). Of these, 29 were in the left atrium and constituted our study group. In 21 patients, the thrombi were successfully aspirated from the left atrium using strong suction through the transseptal sheath. All patients in whom thrombi were aspirated did well without neurological event or death. When patients received heparin therapy either preTS1 or TS1-TS2, there was a significant decrease in the occurrence of ICE-detected left atrial thrombus compared with those who received heparin postTS2 (0 of 31 patients (0%) preTS, 9 of 257 (3.5%) TS1-TS2, and 20 of 220 (9.1%) postTS2; (preTS1 vs postTS2, p = 0.01; preTS2 [preTS1 and TS1-TS2] vs postTS2, p < 0.001). CONCLUSION: Early administration of intravenous heparin, specifically before transseptal puncture, decreases the incidence of left atrial thrombi.  相似文献   
943.
AIMS: Global angiographic scores have been developed to determine the extent of myocardium jeopardized by significant coronary stenosis. We adapted these scores to quantify the anatomic area at risk during acute myocardial infarction. We used contrast-enhanced magnetic resonance (CMR) infarct imaging to measure the portion of myocardium that developed necrosis within the so defined angiographic area at risk. METHODS AND RESULTS: In 83 subjects presenting for primary percutaneous intervention, the myocardium at risk was estimated angiographically using the Myocardial Jeopardy Index (BARI) and a modified version of the Alberta Provincial Project for Outcome Assessment in Coronary Heart Disease (APPROACH) scores. CMR was performed within a week to measure infarct size, infarct endocardial surface area (infarct-ESA), and infarct transmurality. As infarct transmurality increased, the infarct size closely approximated the myocardium at risk by angiography. In 35 subjects with transmural infarcts, the area at risk by BARI and APPROACH scores matched the infarct size (r = 0.90 and r = 0.92, P < 0.001). Additionally, BARI and APPROACH scores matched the infarct-ESA in all subjects independently of collateral flow and time to reperfusion (r = 0.90 and r = 0.87, P < 0.001). The presence of early reperfusion, collaterals, or both was associated with a progressive decrease in infarct transmurality (P < 0.001 for trend) with no difference in the infarct-ESA. CONCLUSION: The myocardium at risk of infarction can be determined angiographically as validated in subjects with transmural myocardial infarcts. Salvage provided by early reperfusion or collaterals occurs by limiting infarct transmurality, thereby the extent of endocardial infarct involved also allows estimation of the myocardium at risk in patients presenting with STEMI.  相似文献   
944.
A regulatory role of acute changes in plasma concentration of free fatty acids on glucagon secretion has been suggested. We have studied the effect of such changes on plasma levels of glucagon, insulin, and growth hormone in man. Basal plasma levels of immunoreactive glucagon (IRG) were only slightly raised in 11 healthy subjects when the mean concentration of free fatty acids (FFA) was depressed to levels as low as 0.315 ± 0.043 (SEM) mM by infusion of nicotinic acid. Basal levels were increased modestly when the mean FFA level was elevated to 3.027 ± 0.184 mM by infusion of a triglyceride emulsion (Intralipid) with heparin. The plasma IRG response to intravenous arginine was unaffected by high or low levels of plasma FFA. These findings contrasted with the effects upon plasma levels of immunoreactive insulin (IRI) and growth hormone (IGH). During elevation of FFA levels, the mean basal level of plasma IRI increased by 100%, and the IRI response to arginine increased by 50%. Concomitantly, basal IGH levels and the plasma IGH response to arginine were suppressed markedly by elevation of FFA levels. The results of these studies do not offer support for a significant role of variation in plasma level of FFA as a regulator of acute changes in plasma IRG in man. An influence of changing levels of FFA on insulin secretion was found, and an effect on levels of growth hormone was confirmed.  相似文献   
945.
946.
OBJECTIVE: The aim of this study was to evaluate the changes in height, weight and in the prevalence of overweight and obesity between 1992 and 2000 in children living in two towns of northern France. METHODS: Two cross-sectional studies were performed in every pre-school (last section) and primary schools of the two towns in 1992 (383 girls and 421 boys enrolled) and 2000 (296 girls and 305 boys). Children were 5 to 12 year old in both studies. MEASUREMENTS: Body height and weight were measured, and BMI was calculated (weight/height(2)). Prevalence of overweight and obesity was determined according to the gender- and age- specific cut-offs of the new international reference (IOTF). We also used the 90(th) and the 97(th) percentiles of the French reference gender- and age-specific BMI curves to define two grades of overweight. RESULTS: After adjustment for age, boys were on average 1.5 cm taller in 2000 than in 1992 (p<0.001), and the same trend was observed in girls (+ 0.9 cm, p<0.075). Height-adjusted or age-adjusted weight and BMI were significantly higher in 2000 than in 1992. In girls, obesity defined by IOTF criteria increased from 1.6 to 4.4% (p<0.03) and overweight from 14.1 to 18.6% (p<0.11). In boys, the change in prevalences was significant only when the less stringent criteria (i.e. the 90(th) percentile of French references) was used (13.8% in 1992 vs 20% in 2000, p=0.03). CONCLUSION: Over an 8 years period, there was an increase in height and BMI in both boys and girls. These results show that the increase in the prevalence of obesity is accompanied by a global trend of accelerated growth.  相似文献   
947.
Two distinct clinical patterns, encephalitic (furious) and paralytic (dumb), have been recognized in human rabies. It has been postulated that different rabies virus variants associated with particular vectors may be responsible for these different clinical manifestations. Analysis of the glycoprotein (G), nucleoprotein (N), and phosphoprotein (P) genes of rabies viruses from 2 human cases of encephalitic rabies and from 2 human cases of paralytic rabies demonstrated only minor nucleotide differences. Deduced amino-acid patterns of the N protein were identical in both human and canine samples that came from the same geographic location, regardless of the clinical form. All differences in amino-acid patterns of the G protein were found outside the ectodomain, in either the signal peptide or the transmembrane and endodomains. None of the amino-acid differences of the P protein was within the interactive site with dynein. These findings support the concept that clinical manifestations of rabies are not explained solely by the associated rabies virus variant.  相似文献   
948.
949.
INTRODUCTION: Self-expanding metal stents are now an established treatment for malignant colonic obstruction. Favorable outcomes have been reported both for cancer palliation and treatment of acute obstruction as a bridge to surgery. However, little data exists regarding the use of stents for benign colonic obstruction.METHODS: All cases of colonic stent insertion occurring between December 1996 to October 2002 were reviewed. During the study period, 36 patients with malignant obstruction and 6 patients with benign obstructive disease underwent placement of self-expandable stents using a combined endoscopic and fluoroscopic technique.RESULTS: Stent placement was successful in 36 of 42 patients (86 percent). Complications occurred in 16 of 36 patients (44 percent): migration (n = 7), reobstruction (n = 5), perforation (n = 2), fistula formation (n = 1), and stent fracture (n = 1). Stent placement was successful in 100 percent of patients with benign strictures but poststent migration was frequent (2/6).CONCLUSIONS: Stent insertion provided an effective outcome in patients with malignant colonic obstruction as a palliative and preoperative therapy. Although a relatively high migration rate was observed in patients with benign strictures, stenting was still effective in providing luminal patency (median follow-up, 7.5 months). Stenting should be considered as a first-line treatment for malignant strictures and as a potential therapy for selected benign strictures.  相似文献   
950.
Transthoracic echocardiography (TTE) has substantial limitations for the study of abnormalities of the coronary tree. Transesophageal echocardiography (TEE) allows a more complete examination of the coronary arteries, particularly the proximal segments. This report describes the use of TEE after cardiac catheterization in the clinical management of a patient with unstable angina. While angiography first showed the giant aneurysm of the left circumflex coronary artery, TEE, by revealing an active thrombus of the lumen, prompted an immediate surgical resolution.  相似文献   
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