Search results for "imulation"
showing 10 items of 7271 documents
Electrophysiology of the Guinea-pig Pineal Organ: Sympathetic Influence and Different Reactions to Light and Darkness
1979
Publisher Summary Recent electrophysiological studies have shown that the guinea-pig pineal organ comprises two main categories of intrinsic cells, which are (a) pinealocytes which are predominantly influenced by central commissural fibers and (b) pinealocytes which are exclusively influenced by peripheral sympathetic fibers. The first group comprises spontaneously active cells which respond to olfactory, acoustic and short-term optic stimuli respectively. After sympathectomy their spontaneous activity is diminished but not suppressed. The second group comprises spontaneously active cells, which do not respond to short-term sensory stimulation and whose activity depends on the environmental…
Newborn rabbit responsiveness to the mammary pheromone is concentration-dependent.
2004
The effect of the intensity of odour signals has rarely been investigated in the regulation of odour-guided behaviour in young mammals. This series of experiments used the mammary pheromone (MP) of the female rabbit to assess the influence of stimulus concentration on neonatal pup responsiveness. The MP is a single compound isolated from rabbit milk that releases in pups the typical head searching and oral seizing behaviour. The pups (n = 621) were exposed to graded concentrations of the MP in bioassays varying in stimulus delivery conditions. Experiment 1 demonstrated that in aqueous dilutions the MP efficiently elicits behavioural responses only within a limited range of concentrations (f…
Simulation-based education for cardiopulmonary resuscitation and airway management protocols: a brief report of a systematic review and meta-analysis.
2014
We aimed to summarize the efficacy of simulation-based education in cardiopulmonary resuscitation and airway management [1].
Secretory effect of azodisalicylate (azodisal sodium) on the short circuited mucosa of the rat ileum in vitro.
1988
Azodisalicylate (ADS) is one of the newly developed substitutes of sulphasalazine consisting of two molecules of 5-amino-salicylic acid. Azodisalicylate caused diarrhoea in some patients, apparently caused by an antiabsorptive secretagogue action of this compound. The mechanism of this was studied in the short circuited isolated mucosa of the rat ileum. Mucosal addition of ADS increased the potential difference (PD) and short circuit current (Isc) at a concentration of 1.3.10(-4) mol/l (4 mg/dl) with maximal effects at 1.3.10(-3) mol/l (40 mg/dl). Epithelial resistance was only slightly decreased at the higher concentrations of 40 and 100 mg/dl. Serosal ADS had no effect on electrical param…
Recommendations for the clinical use of somatosensory-evoked potentials
2008
The International Federation of Clinical Neurophysiology (IFCN) is in the process of updating its Recommendations for clinical practice published in 1999. These new recommendations dedicated to somatosensory-evoked potentials (SEPs) update the methodological aspects and general clinical applications of standard SEPs, and introduce new sections dedicated to the anatomical-functional organization of the somatosensory system and to special clinical applications, such as intraoperative monitoring, recordings in the intensive care unit, pain-related evoked potentials, and trigeminal and pudendal SEPs. Standard SEPs have gained an established role in the health system, and the special clinical ap…
Oxygen consumption is a quality marker for human oocyte competence conditioned by ovarian stimulation regimens.
2011
Objective To evaluate the effect of different ovarian stimulation protocols on oocyte respiration and to investigate the relationship between oocyte oxygen consumption and reproductive outcome. Design Prospective observational cohort study. Setting Infertility clinic in a university hospital. Patient(s) A total of 349 oocytes from 56 IVF treatment cycles in our oocyte donation program. Intervention(s) None. Main Outcome Measure(s) Average oocyte oxygen consumption rate in fmol/s. We correlated oxygen consumption values with ovarian stimulation features, fertilization, embryo quality on days 2 and 3, and implantation. Result(s) Differences in the measured oxygen consumption rates were found …
Pre- and Postjunctional Muscarinic Receptors in the Guinea-pig Trachea
1991
ABSTRACT The effects of M2- and Me-selective muscarinic antagonists on electrically evoked [3H]acetylcholine release and muscle contraction were compared in the isolated guinea-pig trachea. The M2-selective antagonists methoctramine and AF-DX 116 were more potent in enhancing the evoked release than in inhibiting the contractile response. As a consequence of the selective blockade of the inhibitory autoreceptors the evoked muscle contractions were enhanced by low concentrations (0.1 μmol/l) of the M2-selective antagonists. The Me-selective antagonists 4-DAMP, UH-AH 37 and pFHHSiD were more potent in reducing the contraction than in facilitating the evoked release. Surprisingly, HHSiD did no…
Corticospinal and intracortical excitability is modulated in the knee extensors after acute strength training.
2021
The corticospinal responses to high-intensity and low-intensity strength-training of the upper limb are modulated in an intensity-dependent manner. Whether an intensity-dependent threshold occurs following acute strength training of the knee extensors (KE) remains unclear. We assessed the corticospinal responses following high-intensity (85% of maximal strength) or low-intensity (30% of maximal strength) KE strength-training with measures taken during an isometric KE task at baseline, post-5, 30 and 60-min. Twenty-eight volunteers (23 ± 3 years) were randomized to high-intensity (n = 11), low-intensity (n = 10) or to a control group (n = 7). Corticospinal responses were evoked with transcra…
Causal analysis of short-term cardiovascular variability: state-dependent contribution of feedback and feedforward mechanisms.
2016
Baroreflex function is usually assessed from spontaneous oscillations of blood pressure (BP) and cardiac RR interval assuming a unidirectional influence from BP to RR. However, the interaction of BP and RR is bidirectionalâRR also influences BP. Novel methods based on the concept of Granger causality were recently developed for separate analysis of feedback (baroreflex) and feedforward (mechanical) interactions between RR and BP. We aimed at assessing the proportion of the two causal directions of the interactions between RR and systolic BP (SBP) oscillations during various conditions, and at comparing causality measures from SBP to RR with baroreflex gain indexes. Arterial BP and ECG sig…
Role of causality in the evaluation of coherence and transfer function between heart period and systolic pressure in humans
2004
To elicit the effects of considering causality in the study of the interactions between RR interval and systolic pressure (SP) variability, the traditional noncausal cross-spectral analysis was compared with a causal method able to separate the two arms of the RR-SP regulatory loop. Estimates of coherence (K) and causal coherences from SP to RR (Ksr) and from RR to SP (Krs), and of noncausal (G) and causal (Gsr) baroreflex gain were evaluated at 0.1 Hz in 10 healthy young subjects in the supine position and after head-up tilt. While K was high in both conditions, at rest Ksr was significantly lower than Krs. After tilt, Ksr increased and Krs decreased significantly. With respect to G, Gsr w…