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F Fossati

Publications and source records attributed to F Fossati.

At least 19 recordsLinked to original sources
PubMed1996

[Ablation of the slow pathway in reciprocating nodal rhythms by radiofrequency].

Radiofrequency ablation is a therapeutic alternative to drug therapy in recurrent reciprocating nodal rhythms. Selective ablation of the slow pathway guided by endocavitary recordings has the advantage of being effective at the price of a very low incidence of atrioventricular block. The authors report their experience with this technique. Fifty consecutive patients with recurrent attacks which were syncopal or uncontrolled by medical therapy, underwent selective ablation of the slow pathway. Firstly, they all underwent electrophysiological investigation to confirm the nodal origin of the reciprocating rhythm before proceeding to ablation itself, guided by the search for the slow pathway potentials. After ablation, it was impossible to trigger reciprocating tachycardia. Interruption of the anterograde slow pathway was achieved in 24 patients and of the retrograde pathway in 1 patient : the other 25 patients went on having dual conduction but with a prolongation of the effective refractory period of the slow pathway (268 +/- 46 ms vs 251 +/- 41 ms : p < 0.01). There were no cases of permanent complete atrioventricular block. Interruption of the slow pathway was associated with shortening of the effective refractory period of the rapid pathway (323 +/- 71 ms vs 348 +/- 80 ms : p < 0.01), which was not observed in cases of persistent dual conduction. No recurrence of tachycardia was observed during follow-up (mean period = 19.2 months) : however, control endocavitary studies in 25 asymptomatic patients after 1 to 3 months showed recurrence in 4 cases, which led to immediate further radiofrequency ablation which was successful. The authors conclude that guided selective radiofrequency of the slow intranodal pathway is a remarkably effective and reliable method of treating poorly tolerated or resistant reciprocating nodal tachycardias. Widening of the clinical indications to patients not wishing to undergo long-term antiarrhythmic therapy is now possible.

Adolescent↗
PubMed1993

A soap technique for cell separation to study the seed coat of Sesbania punicea.

A technique is described for separating plant cells used for morphological studies. The plant material is placed in a concentrated solution of olive oil castile soap for 1-2 days or more. The material is then thoroughly washed and placed between two glass slides. The upper glass slide is lifted from the lower one, then gently pressed down several times. Through this procedure Malpighian cells of the seed coat of Sesbania punicea, mesophyll cells of Euphorbia peplus and of Trifolium pratense and cortical cells of the aerial roots of Monstera deliciosa have been separated. Various shapes of the Malpighian cells of the Sesbania punicea seed coat can be observed along with intermediates.

Cell Separation↗
PubMed1993

[Contribution of transesophageal echocardiography in the diagnosis of intra- and para-cardiac masses].

The authors detected 59 thrombi and 7 intra- or paracardiac tumors in 58 patients in a series of 1,100 transesophageal echocardiography. Twenty-six of the 51 patients with a thrombus were in sinus rhythm; 25 had atrial fibrillation. In 44 cases, the thrombus was single and in 7 cases there were multiple thrombi. A phenomenon of spontaneous contrast in the left atrium was observed in 24 patients (47%). In 31 cases (53%) the thrombi were located in the left auricle, in 21 cases (36%) in the left atrium, in 4 cases in the left ventricle and in 3 cases in the right atrium. Transthoracic echocardiography only detected 25% of these thrombi. The superiority of transesophageal echocardiography was particularly evident for the detection of thrombi in the left auricle (31 by transesophageal echocardiography versus 2 by transthoracic echocardiography) and in the left atrium (13 by transesophageal echocardiography versus 7 by transthoracic echocardiography). Five myxomas were diagnosed by transesophageal echocardiography and 4 of them were identified by transthoracic echocardiography. The site of implantation of the tumor was located in all 5 cases by transesophageal echocardiography. Two right paracardiac tumours were only visible by transesophageal echocardiography. Transesophageal echocardiography is therefore very useful in the diagnosis of thrombi in the left atrium and auricle, of rare hypodense myxomas and paracardiac tumors. In addition, it enables precise localisation of the site of implantation of nearly all intracardiac tumors.

Aged↗
PubMed1987

Determination of vinyl chloride monomer residue in poly(vinyl chloride) at the parts-per-billion level with an automatic purge-and-trap technique.

A method for the determination of vinyl chloride residue in poly(vinyl chloride) using a commercial purge-and-trap ancillary unit has been developed. Concentrations lower than 10 ppb (10(9] with relative standard deviations in the region of 10% in up to 24 samples are detectable with fully automatic operation without operator attendance. With multiple extraction of the same sample an external standard is used; the matrix does not have any influence on the recovery of vinyl chloride.

Chromatography, Gas↗