Search results for " star"
showing 10 items of 1194 documents
Red cell enzyme polymorphisms in Bulgaria.
1972
7 human red cell enzyme polymophisms have been typed on a sample of n=138 unrelated adults from Bulgaria, which revealed the following gene frequencies: ADA1=0.8623. ADA2=0.1376; AK1=0.9637, AK2=0.0362; 6-PGDA=0.9891, 6-PGDC=0.0108; PGM11=0.8346, PGM12=0.1653; PA=0.1596, PB=0.7983, PC=0.0420. In the LDH-system one B-subunit variant was found, whilst no Peptidase A or B variant could be observed. The anthropological significance of these findings is discussed.
Preparedness for landing after a self-initiated fall.
2012
A startling auditory stimulus (SAS) causes a faster execution of voluntary actions when applied together with the imperative signal in reaction time tasks (the StartReact effect). However, speeding up reaction time may not be the best strategy in all tasks. After a self-initiated fall, the program for landing has to be time-locked to foot contact to avoid damage, and therefore advanced execution of the program would not be convenient. We examined the effects of SAS on the landing motor program in 8 healthy subjects that were requested to let themselves fall from platforms either 50 or 80 cm high at the perception of a visual imperative signal and land on specific targets. In trials at rand…
The effects of a startle on awareness of action
2003
The execution of a ballistic movement within a reaction time task paradigm is significantly speeded up when an unexpected startling auditory stimulus (SAS) is delivered together with the imperative signal. Using Libet's clock, we investigated whether acceleration involves also the subjective appraisal of the time of task execution. In trials containing the SAS, reaction time shortened to 68.7% of control values. However, subjective judgment of task execution remained a similar time with respect to the imperative signal as in control trials. The dissociation between task execution and its subjective perception indicates the existence of separate circuits for action execution and action aware…
Fear expression and return of fear following threat instruction with or without direct contingency experience
2016
Prior research showed that mere instructions about the contingency between a conditioned stimulus (CS) and an unconditioned stimulus (US) can generate fear reactions to the CS. Little is known, however, about the extent to which actual CS-US contingency experience adds anything beyond the effect of contingency instructions. Our results extend previous studies on this topic in that it included fear potentiated startle as an additional dependent variable and examined return of fear (ROF) following reinstatement. We observed that CS-US pairings can enhance fear reactions beyond the effect of contingency instructions. Moreover, for all measures of fear, instructions elicited immediate fear reac…
Early and late histamine release induced by albumin, hetastarch and polygeline: some unexpected findings.
2003
Objective: The perioperative use of colloidal plasma substitutes is still under discussion. We therefore conducted a prospective randomised study with three commonly used plasma substitutes to examine their histamine releasing effects in 21 volunteers. Material or subjects: 21 male volunteers were enrolled in this prospective, randomised, controlled clinical study. Endpoints were the incidence of early and late histamine release and the time course of the release kinetics. Normovolemic hemodilution technique was used with hydroxyethyl starch (n = 6), human albumin (n = 6) and polygeline (n = 9). Measurement and observation period was 240 min after the start of the plasma substitute infusion…
Cardiac modulation of startle is altered in depersonalization-/derealization disorder: Evidence for impaired brainstem representation of baro-afferen…
2016
Patients with depersonalization-/derealization disorder (DPD) show altered heartbeat-evoked brain potentials, which are considered psychophysiological indicators of cortical representation of visceral-afferent neural signals. The aim of the current investigation was to clarify whether the impaired CNS representation of visceral-afferent neural signals in DPD is restricted to the cortical level or is also present in sub-cortical structures. We used cardiac modulation of startle (CMS) to assess baro-afferent signal transmission at brainstem level in 22 DPD and 23 healthy control individuals. The CMS paradigm involved acoustic startle stimuli (105dB(A), 50ms) elicited 0, 100, 200, 300, 400 and…
Excitability of subcortical motor circuits in Go/noGo and forced choice reaction time tasks
2006
The size of the response to a startling auditory stimulus (SAS) may reflect the excitability of the reticulospinal tract. In this study, we examined whether there was any excitability change in the reticulospinal tract during preparation for execution of two types of choice reaction time task: a forced choice reaction time task (fCRT) and a Go/no-Go task (GnG). In 13 healthy volunteers we used three types of trials: control trials in which subjects were requested to perform ballistic wrist movements during fCRT or GnG tasks; test trials in which a SAS was presented with the visual cue, and baseline trials in which SAS was presented alone. Latency and area of the responses to SAS were measur…
Macroamylasaemia after treatment with hydroxyethyl starch
1977
After infusion of 500 ml of 6% hydroxyethyl starch into fifty-four patients an increase of serum amylase was observed which in fifty-one cases exceeded the upper limit of normal (190 U/l). In most cases serum amylase reached twice the basal value. Renal function influenced the duration of the increase in serum amylase, but not the maximum increase (201+/-15 U/l; mean+/-SEM). In patients with advanced renal failure (glomerular filtration rate (GFR) = 2-10 ml/min) serum amylase was still markedly elevated after 72 h (298+/-24 U/l; mean+/-SEM). In patients with normal renal function (GFR greater than 90 ml/min) serum amylase decreased to 183+/-40 U/l (mean+/-SEM) within 72 h without reaching b…
[Treatment of sensorineural hearing loss in acute viral otitis media with intratympanic dexamethasone and hyaluronic acid in comparison with intraven…
2006
Background: Intratympanic dexamethasone with hyaluronic acid has shown to be an effective treatment of the inner ear damage in sudden hearing loss and Meniere's disease. It is not known yet if the same applies to the toxic inner ear damage in acute viral otitis media. Patients: Retrospectively, 26 patients who suffered from acute viral otitis media with sensorineural hearing loss were examined with regard to the improvement of their inner ear hearing loss. Twelve patients were treated with intravenous therapy only, consisting of hydroxyethylstarch, pentoxifylline and prednisolone. Fourteen patients additionally received intratympanic injections, consisting of dexamethasone and hyaluronic ac…
Effects of post-extinction l-DOPA administration on the spontaneous recovery and reinstatement of fear in a human fMRI study
2015
Relapse is a pertinent problem in the treatment of anxiety disorders. In the laboratory, relapse is modeled as return of conditioned fear responses after successful fear extinction and is explained by insufficient retrieval and/or expression of the fear-inhibitory extinction memory that is generated during extinction learning. We have shown in mice and humans that return of fear can be prevented by administration of a single dose of the dopamine precursor l-3,4-dihydroxyphenylalanine (l-DOPA) immediately after extinction. In mice, this effect could be attributed to an enhancement of extinction memory consolidation. In our human study, we could not exclude that l-DOPA might have acted by int…