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Biomedical subjects

R Frank

Publications and source records attributed to R Frank.

At least 595 records · Page 33Linked to original sources
PubMed1976

[Epicardial scintigraphy in 4 cases of ventricular tachycardia caused by reentry of blood after myocardial infarct. Origin of the tachycardia and surgical approach].

110 point cartography was carried out over the ventricular pericardium during sinus rhythm (SR) and during ventricular tachycardia (VT) in four patients whose infarctions were 15 days, 4 months, 4 years and 7 years previously, and in whom electrocardiographic investigation had suggested a ventricular reentry phenomenon. The macroscopical appearances of the heart at operation suggested that the infarct was situated along the left side in two cases, and in or along the septum in two others. Cartography in sinus rhythm showed that the onset of ventricular activity was compatable with a site of origin in the node/bundle of His. Cartography during VT showed up the epicentre of the abnormal impulses which were always situated outside the exit points and dependent upon the node/bundle of His system as demonstrated by cartography in sinus rhythm. Moreover, in at least two cases this was found to lie outside the infarcted area, in portions of the myocardium which could be considered as healthy. In one case it was found to lie along the anterior interventricular groove, facing the septal infarct. In two cases the arrhythmia will not recur, one having achieved this status bu simple ventriculotomy. The failures are reported in relation to the extent of the lesion anatomically, which may cause disorientation of the surgical approach, and make the results difficult to interpret.

Aged↗
PubMed1976

[Epicardial scintigraphy in 4 cases of ventricular tachycardia caused by reentry of blood after myocardial infarct. Study of intra-ventricular conduction disorders in sinus rhythm and in tachycardia, and their relations to anatomical data].

Ventricular pericardial cartography in sinus rhythm (SR) and during ventricular tachycardia (VT) in four cases of myocardial infarction has yielded additional information in the study of conduction disorders in myocardial ischaemia: 1. The significant slowing of activity in SR as well as in VT is demonstrated by this direct method. It is associated with a diminution in amplitude of the pericardial potentials in the zones affected by the ischaemia; 2. Cartography during VT accentuates or reveals disorders of conduction which are slight or latent in SR; 3. Disorders of intra-ventricular conduction are found to be related either to segmental blocks on the branches of the bundle of His, or as focal blocks (peri-infarct block) on the left side, whose nature can be shown up even during VT; 4. Secondary activation of the myocardial fiber found to be related either to segmental blocks on the bundle of His during VT is demonstrated.

Arrhythmia, Sinus↗
PubMed1975

Residue of organochlorine compounds and mercury in birds' eggs from the Niagara Peninsula, Ontario.

Eggs (307) were collected in 1971 from twenty species of birds with a variety of feeding habits from the Niagara Peninsula. This area of ontario is intensively developed for agriculture and heavy industry and has a large urban population. Representative species were obtained from both the terrestrial and aquatic food chains. Eggs were analyzed for organochlorine insecticides, polychlorinated biphenyls, and total mercury. Eggs from carnivorous species at the top of the aquatic food chain had the highest mean residues of signa DDT(7.6to 22.4 pm), PCB (3.5 to 74.0 ppm) and total mercury (0.64 to 0.83 ppm). Eggs from some terrestrial carnivores (red-tailed hawk and great horned owl) also had relatively high residues (2.5 to 3.9 ppm of sigmaDDT, 0.2 to 1.0 ppm of PCB, 0.06 to 0.09 ppm of mercury, however levels were much lower than those found in eggs from aquatic-feeding carnivores. Eggs from one red-shouldered hawk had residues comparable to the aquatic feeding carnivores. Eggs from herbivorous and insectivorous birds of both aquatic and terrestrial environments contained much lower residues. PCB residues were slightly lower in eggs among the terrestrial feeding species (0.05 to 2.0 ppm) than among the aquatic feeders (0.14 to4.0 ppm) and tended to be lower in eggs from terrestrial species collected in rural than incity environs. Levels of sigmaDDT were similar in both groups with eggs from terrestrial feeders containing mean resisues between 0.15 and 2.64 ppm and those from aquatic feeders between 0.33 and 2.79 ppm.

Animals↗
PubMed1975

Lung volumes, mechanics, and single-breath diffusing capacity in anesthetized cats.

We measured lung weight, lung volumes, pulmonary mechanics, and carbon monoxide transfer (DLCO, single-breath method) in healthy cats (3.3 +/- 0.4 kg) that were anesthetized, paralyzed, and mechanically ventilated through a tracheal cannula. Compared with Stahl's predicted values which were based on regression analyses of data collected from several species, our cats had larger and more compliant lungs in relation to body weight, higher DLCO per unit body weight, and similar DLCO/TLC (size independent constant). Compared with Robinson et al.'s values derived entirely from studies on dogs, our cats had significantly smaller lung volumes and DLCO per unit body weight, DLCO/TLC and similar ratios of CL/FRC. Several factors appear to contribute to the functional variations among mammalian species: differences in the relation of lung to body weight, differences in the relation of chest wall compliance to lung compliance, and differences in the fundamental structure and design of the respiratory systems. Differences in methodology are acknowledged to be an additional factor.

Anesthesia↗
PubMed1975

Total synthesis of a structural gene for the human peptide hormone angiotensin II.

Seven oligonucleotide chains containing between 6 and 11 nucleotide units were synthesized. The segments were phosphorylated by T4 polynucleotide 5'-hydroxyl-kinase and joined by T4 polynucleotide synthetase (ATP) to give the double-stranded DNA consisting of 33 base pairs. The DNA sequence was deduced from the known peptide sequence according to the genetic code.

Angiotensin II↗
PubMed1975

[Epicardial cartography and surgical treatment by simple ventriculotomy of certain resistant re-entry ventricular tachycardias].

Intraventricular reentry has been prooved by pre-operative electrophysiological studies in two patients without coronary artery disease and resistant ventricular tachycardia. A simple ventriculotomy oriented by epicardial mapping during tachycardia was successfull with a background of 9 and 14 months respectively. In addition, delayed epicardial potentials put into evidence an intraventricular reentry in human myocardium. This new method holds promises for the treatment of some resistant ventricular tachycardia.

Adult↗
PubMed1975

[Prevention of ventricular tachycardia after myocardial infarction using an intracorporeal pacemaker. Apropos of one case].

Pacemaker implantation is seldom as a treatment of ventricular tachycardia after chronic myocardial infarction. In this new case, pacemaker implantation was successfull for over a year after partial surgery failure. A regular demand pacemaker with bipolar pervenous catheter inserted in the coronary sinus is to give atrial orthorhythmic pacing triggered by ventricular arrhythmias.

Adult↗