(1) Media made hyperosmotic with sucrose increase the frequency of spontaneously released quanta of transmitter, or miniature excitatory postsynaptic potentials (MEPSPs).
(2) Using a model based on airborne transmission, it is estimated that the index patient was producing 144 units of infection (quanta) per minute while in the office.
(3) In contrast to the photosensitivity of ribosome-bound 16S rRNA toward chain breakage, free 16S rRNA seems to be resistant toward photoinduced chain breakage at doses of incident 253.7-nm radiation up to at least 10(21) quanta.
(4) Under normal conditions the amount of maximal facilitation was different for separate EEG quanta and varied from 1.4 to 2.4.
(5) The threshold for light detection is estimated to be the same for both species when specified in quanta incident on the retina.4.
(6) Nifedipine was also found to activate protein kinase C, which in turn induces an increase in the nifedipine-resistant presynaptic Ca2+ influx and in the number of released ACh quanta.
(7) Incubation of rat muscle in the presence of 0.1 mM-monoethylcholine (MECh) and 40 mM-K+ for 60-90 min produced a maximal reduction in the time constant of decay of synaptic currents and potentials, indicating that acetylcholine (ACh) had been replaced by AMECh in the released quanta.
(8) These results were confirmed by analysis of inhibitory quanta in embryonic and adult Mauthner cells involving a small and large number of channels, respectively.
(9) Our measurement procedures were tested using computer-generated 'e.p.c.s' containing randomly occurring 'quanta'.
(10) The data are interpreted that for a given epithelial area there is a periodic build-up of spermatogonia which then produce several successive quanta of spermatocytes and when the spermatogonia are depleted the process repeats.
(11) The co-localization makes it likely that such changes lead to a different relative composition of the secretory quanta of chromaffin granules.
(12) The effect of 4-aminopyridine and tetraethylammonium on the time course of neurotransmitter release was examined at the neuromuscular junction using a computer-aided method which directly measured the time of occurrence of individual quanta.
(13) Let the light-quanta be absorbed in the retina according to a Poisson process.
(14) Furthermore, modulation of transmission proudced by variation in the presynaptic resting potential and during presynaptic inhibition results from changes in the mean number of quanta released by each impulse.
(15) When such thresholds and the intensities of the background lights are expressed in terms of the number of quanta absorbed per unit time, it is found that three factors can be correlated with the thresholds measured in various states of light- and dark-adaptation: (i) the intensity of a steady background, (ii) the rate of regeneration of rhodopsin, and (iii) the amount of metarhodopsin II present in the rods.3.
(16) The paper is concerned with the results of a comparative study of radiation injury of chromosomes of human lymphocytes at the G0 stage resulting from the influence of 60Co gamma quanta and high activity 252Cf radiation sources and depending on a dose and dose rate; with the potentialities of modifying a cytogenetic effect of irradiation by postradiation hyperthermia of cells.
(17) This suggests that large quanta are formed by adding additional ACh to preformed quanta shortly before they are available for release.
(18) A mechanism by which NH stretching quanta are coherently transported along a chain of hydrogen bonded peptide groups is demonstrated by classical simulation of a section of the alpha-helical peptide poly(L-alanine).
(19) Intracellular recordings from single muscle fibres showed that the duration of synaptic currents was longer than in most other vertebrates so far studied and that the number of transmitter 'quanta' released by a single nerve impulse, about 20, was lower, probably reflecting the small size of the presynaptic terminals.
(20) Statistical analysis suggests that the changes in the average numbers of quanta released (m) could be attributed to the change in the immediately available store (n).