(a.) Obstinate in disobedience; contumacious; stubborn; unmanageable; as, a refractory child; a refractory beast.
(a.) Resisting ordinary treatment; difficult of fusion, reduction, or the like; -- said especially of metals and the like, which do not readily yield to heat, or to the hammer; as, a refractory ore.
(n.) A refractory person.
(n.) Refractoriness.
(n.) OPottery) A piece of ware covered with a vaporable flux and placed in a kiln, to communicate a glaze to the other articles.
Example Sentences:
(1) During electrophysiologic study, the effect of propafenone on the effective refractory period of the accessory pathway was determined, as well as its effect during orthodromic atrioventricular (AV) reentrant tachycardia and atrial fibrillation.
(2) Some evidence has shown that platelet crossmatching is useful in multitransfused patients with hypoplastic bone marrows who are refractory to platelet therapy through alloimmunization.
(3) The purpose of this study was to determine the effect of pretreatment with indomethacin on the refractory period to hypertonic saline-induced bronchoconstriction.
(4) This quantitative characterization of the properties of conduction and refractoriness of both the accessory pathway and ventriculoatrial conduction system and the relation between these characteristics and the accessory pathway location in ART patients provides additional insight into the prerequisites for the initiation and maintenance of this rhythm disturbance.
(5) Lisinopril increases cardiac output, and decreases pulmonary capillary wedge pressure and mean arterial pressure in patients with congestive heart failure refractory to conventional treatment with digitalis and diuretics.
(6) Extracorporeal photopheresis (ExP) was administered every other week in an outpatient setting to four patients with chronic refractory psoriasis vulgaris without arthropathy.
(7) Populations of B. globosus and B. nasutus from Dar es Salaam were refractory.
(8) When caffeine evokes a contraction, and only then, crayfish muscle fibers become refractory to a second challenge with caffeine for up to 20 min in the standard saline (5 mM K(o)).
(9) We present in this preliminary report the early results of therapy for refractory leukemia with an intensive preparative regimen for bone marrow transplantation including etoposide, cytosine arabinoside, cyclophosphamide, and fractionated total body irradiation.
(10) Amiodarone was able to suppress the premature ventricular beats, depress conduction and prolong refractoriness in both, the AV node and accessory pathway to prevent recurrences of atrioventricular reentry.
(11) Once initiated, this refractory state continues to develop even after removal of the light source and is essentially complete within 30 min.
(12) At lower frequencies of stimulation the heart beat is increased to rates dependent on interaction between the time course of the hyperpolarization and the refractory period of the heart.
(13) The results indicate that the conditions which inhibit the initiation of development are present in the Malpighian tubules and not in the midgut of the refractory mosquitoes.
(14) Parenteral cyclophosphamide or corticosteroid pulses should be reserved for cases with vasculitis or refractoriness to conventional drugs.
(15) These data suggest that in terms of prolactin release, prolactin producing tumour cells are intrinsically refractory to hypo thalamic dopaminergic signals.
(16) Pirmenol increased the atrial effective refractory period, but had little effect on conduction in the atrioventricular node and His-Purkinje system.
(17) Estramustine phosphate may be given safely for a prolonged period and has a place in the treatment of advanced prostatic cancer refractory to hormonal therapy.
(18) One or more of the followin factors were present in the "high-risk" group: ventricular dysfunction--ejection fraction less than 0.4, preinfarction angina, evolving infarction, recent infarction (less than 2 weeks), and refractory ventricular tachyarrhythmia.
(19) Although video urodynamics is the state-of-the-art modality for evaluating complex or refractory neurogenic bladder, the practicing radiologist with an understanding of this condition can detect many radiographic changes in the lower urinary tract that suggest neurogenic dysfunction of various types.
(20) Tinidazole (not available in the United States) may be effective in curing refractory cases of metronidazole resistance.
Stimulus
Definition:
(v. t.) A goad; hence, something that rouses the mind or spirits; an incentive; as, the hope of gain is a powerful stimulus to labor and action.
(v. t.) That which excites or produces a temporary increase of vital action, either in the whole organism or in any of its parts; especially (Physiol.), any substance or agent capable of evoking the activity of a nerve or irritable muscle, or capable of producing an impression upon a sensory organ or more particularly upon its specific end organ.
Example Sentences:
(1) In the absence of atrial dilatation there was minimal stimulus for ANF secretion.
(2) At the same time the duodenum can be isolated from the stomach and maintained under constant stimulus by a continual infusion at regulated pressure, volume and temperature into the distal cannula.
(3) With glucose and protein as intraduodenal stimulus (no pancreatin added), the plasma amino acids rose significantly less (by approximately 50% of the control experiment) and the increment in insulin (but not C-peptide) concentrations was significantly reduced by loxiglumide.
(4) Since intracellular Ca2+ seems to play a role in stimulus-secretion coupling and ion movements, several aspects of Ca2+ homeostasis have been investigated in CF.
(5) Three coyotes were operantly conditioned to depress one of two foot treadles, left or right, depending on the condition of the stimulus light.
(6) Clinical measurements of the loudness discomfort level (LDL) are generally performed while the subject listens to a particular stimulus presented from an audiometer through headphones (AUD-HP).
(7) NE differentially affected responses to stimulus movement in the preferred and non-preferred direction in one-third of these neurons, such that directional selectivity was increased.
(8) II, the visual and auditory stimuli were exposed conversely over the habituation- (either stimulus) and the test-periods (both stimuli).
(9) The marine vibrio alone is a powerful stimulus to mucus secretion but lethal for the host.
(10) Taken together with our previous studies showing that MDMA substitutes for the phenylisopropylamine stimulant (+)amphetamine, but that neither MDE nor N-OH MDA substitute for (+)amphetamine or for the phenylisopropylamine hallucinogen 1-(2,5-dimethoxy-4-methylphenyl)-2-aminopropane (DOM), the present results [i.e., MDMA-stimulus generalization to MDE, N-OH MDA, but not to (+)amphetamine] suggest that 1) MDMA produces effects other than those that may be considered amphetamine-like, and 2) MDE and N-OH MDA are MDMA-like agents with even less of an amphetamine-like component of action than MDMA itself.
(11) Changes in pain tolerance after administration of differently labelled placebos were studied by measuring the reaction time after a cold stimulus.
(12) 27% of the neurons revealed high sensitivity to the temperature stimulus with coefficient Q10 from 2.4 to 30; 6% of the neurons reacted by the on-response type; 5% of the neurons changed their activity and preserved the new level.
(13) Isolated outer hair cells from the organ of Corti of the guinea pig have been shown to change length in response to a mechanical stimulus in the form of a tone burst at a fixed frequency of 200 Hz (Canlon et al., 1988).
(14) Adhesion and O2- production were also found to be differentially affected by the NADPH oxidase inhibitor diphenylene iodonium, the sulfhydryl reagent N-ethylmaleimide and the A2 agonist adenosine, indicating that these neutrophil responses have various transductional pathways that also depend on the type of stimulus.
(15) The following results were obtained: 1) In normal subjects, the changes in ABR waveforms according to the changes of the rise-time, interstimulus interval and frequency of the stimulus were mainly attributed to component wave C. 2) In patients with central disorders, component wave C were initially affected.
(16) Following each stimulus, the subject had to press a button for RT and then report the digit perceived.
(17) Subjects with high ocular-dominance scores (right- or left-dominant subjects) showed for the green stimulus asymmetric behavior, while subjects with low ocular-dominance scores showed a tendency toward symmetry in perception.
(18) Prior to each long-term intake test, rats received a 1 min, 1 ml intraoral infusion of the same chemical stimulus.
(19) In positive patterning, elemental stimuli, A and B, were presented without an unconditioned stimulus while their compound, AB, was paired with electric shock.
(20) In a recent study, Orr and Lanzetta (1984) showed that the excitatory properties of fear facial expressions previously described (Lanzetta & Orr, 1981; Orr & Lanzetta, 1980) do not depend on associative mechanisms; even in the absence of reinforcement, fear faces intensify the emotional reaction to a previously conditioned stimulus and disrupt extinction of an acquired fear response.