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排序方式: 共有503条查询结果,搜索用时 140 毫秒
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C Tribouilloy V Ruiz R Roudaut JC Eicher B Denis JR Lusson JL Rey JL Schmit JP Lesbre 《Canadian Metallurgical Quarterly》1996,25(28):1276-1280
OBJECTIVES: Identify factors predicting favorable outcome after medical management of valve ring abscesses in order to propose a surveillance schedule for conservative treatment. METHODS: A multicentric study conducted from July 1989 to February 1996 included 28 patients (mean age 64 +/- 16 years, range 26-83) hospitalized for active endocarditis and valve ring abscesses diagnosed at transthoracic or transesophageal echography. Conservative medical therapy was given because of a decision of the medico-surgical team (n = 9), high surgical risk (n = 12), or patient refusal of surgery (n = 7). Outcome was favourable in 18 patients (Group I) and unfavorable in 10 (Group II) due to death (n = 9) or subsequent surgery (n = 1). Univariate and multivariate analysis were used to determine differences between the groups in terms of clinical and laboratory data. RESULTS: Mean follow-up in Group I was 33 +/- 18 months and 15 +/- 10 months in Group II. Univariate analysis showed significant differences between Group I and II respectively for age (59 +/- 18 yr vs 72 +/- 10, p = 0.04), delay to apyrexia after antibiotics (4.3 +/- 2.8 vs 8.3 +/- 2.4 days, p < 0.0008), heart failure (5% vs 70%, p = 0.003), grade III or IV valvular regurgitation (5% vs 60%, p < 0.04), and mean surface area of the abscess (1.5 +/- 1.2 vs 5.4 +/- 6.4 cm2, p < 0.03). Independent factors at multivariate analysis were by decreasing order: lack of heart failure at admission, delay to apyrexia, abscess surface area, and age. Outcome was favorable (mean follow-up 33 +/- 10 months) in all patients with an abscess surface area < 1.5 cm2, no signs of heart failure, no grade III or IV valvular regurgitation, apyrexia after less than 8 days on antibiotics and no staphylococcus positive blood culture. CONCLUSION: Medical management of valve ring abscesses may be indicated in selected patients in care units with rigorous surveillance facilities. Further studies are needed to precisely identify surveillance and treatment criteria. 相似文献
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Occlusion of large atrial septal defects with a centering buttoned device: early clinical experience
EB Sideris M Leung JH Yoon CR Chen R Lochan AM Worms C Rey B Meier 《Canadian Metallurgical Quarterly》1996,131(2):356-359
A feasibility clinical study was conducted for the transcatheter occlusion of large ostium secundum atrial septal defects with the centering buttoned device. The centering buttoned device is a modification of the regular buttoned device in which a centering counter-occluder is sutured at the central 40% portion of the occluder. During centering it is stretched, forming a parachute-shaped structure and pulling the occluder over the center of the defect. During buttoning, the counter-occluder forms a double figure eight, opposing the right atrial side of the atrial septum. Occlusion was performed in 12 patients aged 6 to 56 years. All had been rejected for transcatheter occlusion by the regular buttoned device, because of either their defect size or the lack of adequate septal rim. The defect size varied between 23 and 31 mm, and the device size varied between 45 and 60 mm. Nine had immediate effective occlusions of their defects and three residual shunts. One patient with unbuttoning had hemolysis at 2 weeks and underwent surgery. Early results of the transcatheter occlusion of large atrial septal defects are promising, and larger clinical trials are justified. 相似文献
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INTRODUCTION: The aim of the study was the evaluation of the usefulness of transesophageal atrial pacing in predicting chronic oral treatment efficacy of symptomatic reciprocating supraventricular tachycardia in infants and in avoiding the risk of very dangerous recurrences at home. METHODS: We studied 13 infants (11 males, 2 females, mean age 43 +/- 31 days) with symptomatic reciprocating supraventricular tachycardia and no structural heart disease. All patients had chronic oral therapy, using the drug effective in acute i.v. somministration. Each patient was discharged when supraventricular tachycardia was not inducible with transesophageal atrial pacing after 5 half-lives of the drug used in chronic oral treatment. All patients, every 6 months, were retested with transesophageal atrial pacing alternatively during chronic oral therapy and after complete wash out. Oral therapy was stopped in each patient when supraventricular tachycardia was not inducible after the wash out. RESULTS: The number of oral treatments tested for each patient were 2 +/- 1 (range 1-5). The number of transesophageal studies performed for each patient were 4 +/- 2 (range 3-7). No patient had symptomatic episodes of supraventricular tachycardia or needed to change therapy during the follow-up. The oral treatment was stopped after the twelfth month of life in 8 patients and after the twenty-fourth in 2 others without recurrences. CONCLUSION: Transesophageal atrial pacing seems to be useful in predicting accurately and rapidly the oral treatment efficacy of supraventricular tachycardia in infants. Our protocol seems to be effective to avoid dangerous recurrences of tachycardia and to decide when we can stop therapy without risk. 相似文献
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H Laurichesse M Cambon D Perre T Ancelle M Mora B Hubert J Beytout M Rey 《Canadian Metallurgical Quarterly》1997,7(5):R69-R73
The investigation of a trichinosis outbreak in Auvergne, France identified 23 cases in 12 households living in two cities-Clermont-Ferrand and Montlu?on-between 15 February and 7 March 1991. One patient required intensive care, 15 had major symptoms, and seven had minor or no symptoms. Two case control studies demonstrated a significant (p < 0.01) association between eating horse meat and acute trichinosis. Veterinary services found that three supermarkets where the patients had bought horse meat during the suspected period had been supplied by a single wholesaler. The analysis of the wholesaler's records revealed that the implicated horse meat had been imported from a slaughterhouse in the United States. This outbreak occurred despite a requirement in France for all meat from horses slaughtered in France and in countries exporting meat to France to be examined systematically for trichinella. 相似文献
8.
D Knaack ME Goad M Aiolova C Rey A Tofighi P Chakravarthy DD Lee 《Canadian Metallurgical Quarterly》1998,43(4):399-409
Bacteroides fragilis strains isolated from different sources, i.e. 1 strain (AA1) from an aquatic environment, 1 strain from normal flora (118310) and the type strain (ATCC 25285) originally isolated from clinical material, were analysed for both cell envelope proteins composition and surviving under oxidative stress starvation. All strains examined showed a similar survival response when cultured in drinking water with a ten-fold decrease in viable counts per day during the 7 days of analysis. The outer membrane protein (OMP) profiles of all strains were quite similar during the stress period as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). However, the periplasmic proteins of the strain 118310 showed two protein bands at 48 and 58 kDa, respectively, that were absent in the strains AA1 and ATCC 25285 during the incubation period in potable water. Whole cells and periplasmic 35S-labelled proteins from bacteria cultured in drinking water showed a significant increase in proteins at 16, 18, 24, 26, 35, 48, and 58 kDa and 18, 22, 24, 48, 58, and 70 kDa, respectively, in all strains when compared to cells grown in BHI-PRAS media as detected by autoradiography following SDS-PAGE. These data suggest that B. fragilis may have a synthesis mechanism that allows them to adapt to adverse environments. 相似文献
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F Ballereau I Schrive A Fisch M Speich H Laurichesse S Tournade M Rey 《Canadian Metallurgical Quarterly》1998,14(5):499-503
Syncope is a common medical problem with multiple potential causes and it is very frequent in pediatric population . Neurocardiogenic syncope has been increasingly recognized with the introduction of head-up tilt test (HUTT). The study investigates the clinical utility of HUTT in the evaluation and management of children with recurrent syncope and structurally normal heart. Two-hundred-forty-three consecutive young patients with recurrent unexplained syncope, 100 males and 143 females (mean age 11.4 years, range 5 to 20) underwent HUTT using a 60 degree tilt for 45 min. The test was considered positive when it provoked symptoms of syncope with hypotension and/or bradycardia. Twenty-six patients (10.7%) were positive for neurocardiogenic syncope. Of the 26 patients with the positive tilt, 5 (19.2%) had cardioinhibitory response, 5 (19.2%) mixed response and 16(61.6%) vasodepressive response. Nineteen of 143 females (13.3%) and 7 of 100 males (7%) resulted positive (NS). Among patients < 10 years of age 3/41 (9.8%) were positive and among > 10 years 22/202 patients (10.9%) resulted positive (NS). The cardioinhibitory response is more frequent in males (p = 0.01), and the vasodepressive in females (p = 0.05). In our study, concerning a non selected pediatric population a positive test resulted in a lower percentage than previously reported; moreover, the tilt test has appeared a promising method of identifying patients requiring pharmacotherapy. Additional randomized controlled studies are necessary to better define the prognosis and treatment of neurocardiogenic syncope in children and adolescents with positive tilt test. Finally, an assessment of the outcome of young patients with syncope and a negative tilt test is needed. 相似文献
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In 1881, the French physicist d'Arsonval was the first to suggest the harnessing of the temperature difference between the warm surface layers and cold deep layers of tropical oceans. Since then, several attempts have been made to convert this undepletable supply of thermal potential energy into mechanical energy and, later, into electricity. In recent years, various countries including France have launched thermal energy conversion (OTEC) programmes. Tropical regions with useful temperature differences often lack both conventional energy resources and potable water. In such regions, OTEC plants could be used with advantage for the simultaneous production of power and desalinated seawater.An original seawater distillation scheme using surface water and the cold reject stream from an OTEC cycle is discussed. Power not required for distillation may be exported outside the plant. The combined distillation and OTEC scheme is compared with conventional desalination plant producing both potable water and electricity. The OTEC scheme appears highly flexible and shows considerable economic promise. 相似文献