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At least 19 recordsLinked to original sources
PubMed1978

Superweak interactions and the biological time direction.

A hypothesis is proposed in qualitative terms, according to which left helical electrons in chiral molecules, and right helical electrons in oppositely chiral molecules have different internal timings. The basis of this hypothesis stems from two facts: (1) It has been observed that the decay processes caused by superweak interactions go slower if left helical electrons are produced compared to decay processes in which right helical positrons are produced. (2) The excited states of D and L molecules are not only parity transformed but time reversed pairs as well. Re-evaluation of many data makes the hypothesis likely. The significance of this hypothesis in the origin and evolution of life is apparent since life and evolution as a whole have a special time direction.

Biophysical Phenomena↗
PubMed1975

The extraordinary dielectric properties of biological materials and the action of enzymes.

From very general theoretical considerations it is concluded that many biomolecules (i) should have metastable excited states with very high dipole moment, and (ii) should be capable of strongly excited giant dipole vibrations with frequencies near 10(11) Hz. Experimental evidence available so far seems to support these postulates. It is suggested that the two postulates should be of importance for the action of enzymes, and relevant experiments are proposed.

Chemical Phenomena↗
PubMed1992

Electromagnetic gating in ion channels.

There have been many attempts to develop a theoretical explanation of the phenomena of electromagnetic field interactions with biological systems. None of the reported efforts have been entirely successful in accounting for the observed experimental results, in particular with respect to the reports of interactions between extremely low frequency (ELF) magnetic fields and biological systems at ion cyclotron resonance frequencies. The approach used in this paper starts with the Lorentz force equation, but use is made of cylindrical co-ordinates and cylindrical boundary conditions in an attempt to more closely model the walls of an ion channel. The equations of motion of an ion that result from this approach suggest that the inside shape of the channel plus the ELF magnetic fields at specific frequencies and amplitudes could act as a gate to control the movement of the ion across the cell membrane.

Animals↗
PubMed1978

Phantom pacemaker programming.

Spurious or "phantom" programming of programmable pacemakers may occur as the result of two phenomena. One is change in rate and/or output of the generator from an anomalous source (dysprogramming); the other is a generator response different from that intended and set on the conventional programmer (misprogramming). In either case, the result is a nuisance, at best. Conceivably, at worst, an irreversible subthreshold output could be induced. Despite wide usage of such devices, neither event has been reported. In the routine follow-up of 95 implanted Cordis Omni-Stanicor generators, we have observed three instances of dysprogramming upon application of a magnet commonly used to induce the asynchronous mode. Subsequent in vitro studies revealed magnetically induced programming reed switch vibration in 9 of 6,680 units, which could account for the in vivo observations. We also describe many instances of misprogramming, attributable, in most cases, to a faulty programmer emission count. In this series, none of the anomalies was clinically detrimental. However, anyone involved in pacemaker follow-up should be alerted to the existence of these potentially hazardous phenomena.

Cardiac Pacing, Artificial↗
PubMed1976

An implantable electromagnetic sound source for speech production.

Many operative and nonsurgical procedures have been designed for vocal rehabilitation following laryngectomy, but as yet a consistently successful solution with a negligible complication rate has failed to materialize. In our laboratory during the last two years, experiments have been carried out in dogs using active electromagnetic devices placed in the retropharynx as an energy source for speech production. An implantable porous coated stainless steel electromagnetic device energized from an externally controlled oscillator has been developed. Factors under investigation included biocompatibility of materials, durability, noise quality and intensity, together with the efficiency of the system. As a result of the favorable findings, it is envisaged that this system will soon be used in a carefully designed restricted clinical trial as a secondary procedure in those consenting cured laryngeal cancer patients who have failed to develop esophageal speech.

Animals↗
PubMed1976

Effect of glucagon on hepatic circulation in the pig.

The effect of intravenous injection of 50 mug/kg of glucagon on the hepatic circulation of the pig was studied in 12 animals. Glucagon caused an arterial pressure reduction of 11 mm Hg after two minutes and 7 mm Hg after ten minutes. The portal pressure and blood flow were not altered. The superior mesenteric arterial flow decreased by 12%. The hepatic arterial blood flow increased by 80% after two minutes and by 58% after ten minutes. There was no difference in response when anesthesia was achieved with small intravenous doses of thiopental (Pentothal) sodium or 70% nitrous oxide in oxygen and tubocurarine chloride.

Animals↗
PubMed1978

Hepatic blood flow measurement.

Although many experimental studies have been made to determine the total hepatic blood flow in steady circulatory states, very few have been done in unsteady states of either circulatory overload or underload. In this experiment, a comparison is made between total hepatic blood flow measured by the single injection of indocyanine green and the electromagnetic flow methods in the dog, in which circulatory overload was induced by dextran 40 infusion. While there was close correlation between the values obtained by the two methods in normal dogs, following dextran infusion the indirect indocyanine green method overestimated hepatic blood flow by 40% to 60%, using the electromagnetic method as a comparison standard. The reason for this discrepancy is not elucidated by these studies.

Animals↗
PubMed1978

Muscle and subcutaneous oxygen tension. Measurements by mass spectrometry after sympathectomy.

Utilizing the mass spectrometer, tissue oxygen tension (TPO2) in the resting state was measured in the extremities of ten dogs before and after lumbar sympathectomy. Although there was considerable variation between individual dogs, significant changes in tissue oxygenation were not consistently obtained in the group as a whole, althouth femoral arterial blood flow increased in all animals. Using TPO2 changes to estimate perfusion, no significant increase in nutritive flow could be demonstrated.

Animals↗
PubMed1976

Electromagnetic induced kinetic effects on charged substrates in localized enzyme systems.

An analytical expression for the rate efficiency factor of planar localized enzyme systems is derived. The derivation takes into account the isothermal kinetic effect under the externally imposed perturbation of combined electrostatic and high frequency time-varying fields. The contribution of each individual field to the enzyme reaction is examined through the basic mechanism in which charged substrates interact with the specific perturbing field. The interaction mechanisms for the electrostatic and for the time-varying fields are found to be different. This difference regulates the different manners in which enzymatic reaction rates are altered. Enzymatic reactions under electrostatic perturbation can be retarded or enhanced depending on the field polarization. At sufficiently high field intensities the reaction rate may approach zero or approach a maximum value equal to the turnover number of the enzyme. Time-varying field perturbations, on the other hand, always enhance the enzymatic reactions if bunching effects are negligible. At sufficiently high field intensities, the reaction may approach a value equal to that of the free enzyme system. Several typical numerical examples on pure eletrostatic field perturbations, pure time-varying field perturbations, and combined field perturbations are also presented.

Electromagnetic Phenomena↗