SEARCH · PubMed Health

Results for “The Right to Reproduce”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 181 records · Page 10Linked to original sources

PubMed1997

Idiopathic left ventricular tachycardia with left and right bundle branch block configurations.

INTRODUCTION: Idiopathic left ventricular tachycardia typically has a right bundle branch block configuration. The purpose of this case report is to demonstrate that idiopathic ventricular tachycardia arising in or near the left posterior fascicle also may have a left bundle branch block configuration. METHODS AND RESULTS: A 27-year-old woman underwent an electrophysiologic procedure because of recurrent, verapamil-responsive, wide QRS complex tachycardia. Two types of ventricular tachycardia (cycle lengths 330 to 340 msec) were reproducibly inducible, one with a right bundle branch block configuration and left-axis deviation that had been documented clinically, and the other with a left bundle branch block configuration and axis of zero. A Purkinje potential recorded at the junction of the left ventricular mid-septum and inferior wall preceded the ventricular complex by 40 msec in both tachycardias. A single application of radiofrequency energy at this site successfully ablated both ventricular tachycardias. CONCLUSION: The findings of this case report demonstrate that idiopathic ventricular tachycardia arising in or near the left posterior fascicle may have a left bundle branch block configuration.

Adult↗

PubMed2006

Blood flow in the common carotid artery in term and preterm infants: reproducibility and relation to cardiac output.

AIM: To assess the reproducibility of, and determine normative data for, flow volume measurements from the right common carotid artery (CCA) and its relation to left ventricular output (LVO) in stable term and preterm babies using Doppler ultrasound. METHODS: Right CCA flow volume was measured using a near focus, high frequency transducer by obtaining intensity weighted mean velocity and right CCA diameter. LVO was determined using standard Doppler techniques. Reproducibility studies were performed on 30 newborn infants by two observers. Normative data were obtained from 40 spontaneously breathing preterm babies and 21 term babies. RESULTS: The intraobserver coefficient of variation for CCA flow measurements was 10.5% for observer 1 and 15.4% for observer 2, whereas the interobserver coefficient of variation was 16.4%. In term and preterm infants, right CCA flow was about 20 ml/kg/min, accounting for 11% of cardiac output. Among the preterm infants, there was a positive correlation of right CCA flow with gestation (r = 0.61, p<0.001), weight (r = 0.64, p<0.001), and LVO (r = 0.59, p<0.001). Right CCA diameter also increased with weight (r = 0.63, p<0.001) and gestation (r = 0.58, p<0.001). The proportion of LVO distributed to the right CCA did not increase with gestation, nor did the right CCA flow per kg body weight. CONCLUSIONS: It is possible to perform reproducible measurements of flow volume in the CCA of newborn infants. In stable, spontaneously breathing babies, both cardiac output and carotid flow increased with gestation and body weight. The proportion of cardiac output distributed to the right CCA remained relatively constant across gestation.

Birth Weight↗

PubMed2005

Half right.

Explore the source record for details and available documents.

Reproducibility of Results↗

PubMed1997

Reproducibility of dual-energy X-ray absorptiometry in the upper extremities in stroke patients.

Bone mineral loss after stroke in affected extremities can increase the prevalence of fractures that interrupt the rehabilitation programme and lower the level of activity. In stroke rehabilitation, precise bone mineral measurement is needed in order to assess the risk of fractures. We defined five regions-of-interest of the upper extremity (proximal humerus, distal forearm, distal radius, distal ulna and hand) consistently, so that the position was comfortable for hemiplegic patients to maintain during the measurement. The aim of this study was to determine whether our method using dual-energy X-ray absorptiometry is useful in hemiplegic patients. Ten normal subjects and 15 hemiplegic patients were studied. In normal subjects the reproducibility of our method was evaluated by repeated measurements of both the right and left sides. In hemiplegic patients the reproducibility was evaluated by repeated measurements of the affected side. The coefficient of variation (CV) values were obtained for BMD (0.7-1.7%) and BMC (0.7-2.3%) in normal subjects, and BMD (1.3-2.1%) and BMC (1.7-5.4%) in hemiplegic patients. The CV for the side-to-side BMD and BMC ratios in the normal subjects ranged from 1.1% to 2.2% and from 1.8% to 3.1%, respectively. Our study shows that the reproducibility of our method is sufficient for application to hemiplegic patients.

Absorptiometry, Photon↗

PubMed1989

Comparison of endocardial and epicardial programmed stimulation for the induction of ventricular tachycardia.

Twenty-seven patients who had pairs of stainless steel wire electrodes placed on the right and the left ventricle during cardiac surgery underwent both epicardial and endocardial programmed ventricular stimulation to assess the inducibility of ventricular tachycardia. Twenty-six of the patients had coronary artery disease and were studied to evaluate map-guided surgery for treatment of ventricular arrhythmias. Burst ventricular pacing and up to three ventricular extrastimuli coupled to two drive train cycle lengths were delivered from the right and left ventricular epicardial wire electrodes and from endocardial catheter electrodes placed at the apex and outflow tract of the right ventricle. Ventricular tachycardia was reproducibly induced in three patients by both endocardial and epicardial stimulation. In one patient ventricular tachycardia was reproducibly induced by epicardial stimulation, but nonreproducible, nonsustained ventricular tachycardia was induced by endocardial stimulation. Ventricular tachycardia remained inducible by both endocardial and epicardial stimulation in three instances (two patients) during drug therapy. A negative study (less than 10 consecutive ventricular beats induced) was obtained in 23 patients by both endocardial and epicardial stimulation. The patients were followed up for 12 to 43 months (average 31). Sudden death or documented ventricular tachycardia occurred in two of the three patients with a positive study by both endocardial and epicardial stimulation. Nineteen (83%) of the 23 patients with concordantly negative studies remained free of arrhythmias. On the basis of concordant results of endocardial and epicardial stimulation (p = 0.001) these results suggest that epicardial stimulation of the right and the left ventricle is an acceptable method to assess the postoperative inducibility of ventricular tachycardia.(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiac Pacing, Artificial↗

PubMedDate not supplied

In vitro study of laser diode 655 nm diagnosis of occlusal caries.

The aim of this in vitro study was to evaluate the performance of a new laser method (DIAGNOdent, KaVo) by comparing it to the visual inspection, conventional bitewing radiography and digital bitewing radiography. Fifty fresh permanent teeth with clinically sound or suspicious fissures were selected. The teeth were submitted to the diagnostic tests by 2 examiners independently after calibration. The laser examination was repeated to assess the reproducibility. The teeth were sectioned right in the spot that showed the highest value by the laser device. Histological examination of sections (40x magnification) served as gold standard. The results showed that: 1) the intra and interobserver agreement for the DIAGNOdent was excellent (values over 0.87); 2) the sensitivity, specificity and predictive values were very high; 3) and the Spearman correlation coefficient of DIAGNOdent was the best one (R = 0.81), followed by visual inspection (R = 0.68).

Dental Caries↗

PubMed1999

The endpoints' task: an analysis of length reproduction in unilateral neglect.

When patients with left hemineglect are shown the centre of a memorised line and are asked to mark both the endpoints, they place the left one significantly farther. This contralesional bias appears to be incoherent with respect to most current interpretations of neglect [7]. In the present study, ten patients with left hemineglect and two control groups were presented the centre of a line and one of its endpoints and had to mark the missing one at the correct distance. With this modification, subjects had not to rely on stored information about the line, but simply to reproduce a distance either to the left or to the right separately. The task was performed in three different spatial locations with respect to subjects' body midline. Similarly to the original endpoints' task, neglect patients showed a leftward bias, placing the left endpoint significantly farther than the right one. However, this was not associated with a paradoxical contralesional over-extension with respect to the distance to reproduce. Indeed, when marking the left endpoint, patients were accurate (when performing in the right hemispace) or even underestimated the distance to reproduce (when performing centrally and in the left hemispace). Instead, the leftward bias was due to severe underestimation errors when marking the right endpoint, which were independent of the stimulus location. These results demonstrate that the leftward bias in the endpoints' task is relative rather than absolute and does not reflect a paradoxical overestimation in length reproduction towards the left side.

Adult↗

PubMed1978

Assessment of cardiac performance with quantitative radionuclide angiocardiography: right ventricular ejection fraction with reference to findings in chronic obstructive pulmonary disease.

A reproducible noninvasive technique for measuring righ ventricular ejection fraction was developed using first pass quantitative radionuclide angiocardiography. Studies were obtained in the anterior position with a computerized multicrystal scintillation camera with high count rate capabilities. Right ventricular ejection fraction was calculated on a beat to beat basis from the high frequency components of the background-corrected right ventricular time-activity curve. In 50 normal adults, right ventricular ejection fraction averaged 55 percent (range of 45 to 65 percent). This radionuclide measure of right ventricular function was reproducible, with minimal inter- and intraobserver variability, and was sensitive to changes in inotropic state induced with isoproterenol. In 36 patients with chronic obstructive pulmonary disease, right ventricular ejection fraction ranged from 19 to 71 percent. All 10 patients with corpulmonale, as well as 9 additional patients, had an abnormal right ventricular ejection fraction. Arterial oxygen tension and forced expiratory volume were depressed significantly more in patients with abnormal right ventricular ejection fraction than in subjects with normal right ventricular function. There was no relation between abnormalities in right and left ventricular ejection fraction.

Adult↗

PubMedDate not supplied

Sialic acid in normal human tear fluid.

PURPOSE: We measured the concentration of sialic acid, the terminal component of mucin, in normal diluted human tears. METHODS: Twenty-microliter tear samples were collected from 31 healthy volunteers (average age = 50.7 years) using micropipette after 50 microL instillation of saline. We investigated the correlation of concentration between glycoprotein and sialic acid and the difference between the right and the left eyes, as well as the reproducibility of the sampling procedure. RESULTS: There was significant correlation of the concentration between glycoprotein and sialic acid (right eye: r = 0.952, P <.0001; left eye: r = 0.976, P <.001). There was no significant difference in concentration between the right and the left eyes. Also, the reproducibility was considered acceptable in three measurements of sialic acid using the present procedure. The sialic acid concentration in normal diluted tears was 37.1 microg/mL on average. CONCLUSION: Our data indicates that sialic acid concentration is an indicator for the concentration of glycoprotein and that this method of measurement is applicable to the analysis of mucin-deficient disorders.

Chromatography, High Pressure Liquid↗

PubMedDate not supplied

Elimination of subjective bruit with compression of temporal artery: new physical sign indicative of internal carotid artery occlusion.

A patient is presented with a right central retinal artery occlusion and subjective bruit over right ear. Digital compression of the right temporal artery eliminated the bruit and release reproduced the bruit. Carotid arteriogram showed bilateral internal carotid occlusion with a prominent right temporal artery. This sign reflects compensatory hyper-perfusion of the external carotid artery due to occlusion of ipsilateral internal carotid artery.

Arterial Occlusive Diseases↗

PubMed1991

Reproducibility of renal blood flow estimation in the miniature pig using 99Tcm-DTPA: introducing semiautomatic processing.

This study examines the reproducibility of renal blood flow measurement (RBF) in nine miniature pigs using 99Tcm-DTPA renography, and introduces a new algorithm useful in data processing. Renal blood flow can be estimated using three arterial regions of interest (ROI), the left ventricle (LV), the right lung (RL) and the aorta. Using the LV ROI, left kidney RBF was 9.08 (S.D. 1.69) and right RBF was 10.87 (S.D. 2.26). Reproducibility was assessed by performing renograms on successive days in nine pigs and was found to be best for LV [S.D. of change 0.32 for the left kidney (LK) and 0.74 for the right kidney (RK)] followed by RL (0.77 for LK and 0.75 for RK) and worst for aorta (1.47 for LK and 1.78 for RK).

Algorithms↗

PubMed2002

Twist and shear in beta-sheets and beta-ribbons.

The structures of the beta-sheets and the beta-ribbons have been analysed using high-resolution protein structure data. Systematic asymmetries measured in both parallel and antiparallel beta-structures include the sheet twist and the strand shear. In order to determine the origin of these asymmetries, numerous interactions and correlations were examined. The strongest correlations are observed for residues in antiparallel beta-sheets and beta-ribbons that form non-H-bonded pairs. For these residues, the sheet twist is correlated to the backbone phi angle but not to the psi angle. Our analysis supports the existence of an inter-strand C(alpha)H(alpha)...O weak H-bond, which, together with the CO...HN H-bond, constitutes a bifurcated H-bond that links neighbouring beta-strands. Residues of beta-sheets and beta-ribbons in high-resolution protein structures form a distinct region of the Ramachandran plot, which is determined by the formation of the bifurcated H-bond, the formation of an intra-strand O...H(alpha) non-bonded polar interaction, and an intra-strand O...C(beta) steric clash. Using beta-strands parameterised by phi-psi values from the allowed beta-sheet region of the Ramachandran plot, the shear and the right-hand twist can be reproduced in a simple model of the antiparallel and parallel beta-ribbon that models the bifurcated H-bonds specifically. The conformations of interior residues of beta-sheets are shown to be subsets of the conformations of residues of beta-ribbons.

Databases, Protein↗

PubMed1984

Tachycardia prevention by programmed stimulation.

Ten patients with an atrioventricular accessory pathway were studied by standard electrophysiologic techniques to determine if reentrant tachycardia can be prevented in these patients by delivery of a single extrastimulus, applied at a critical time after the tachycardia-initiating stimulus (or stimuli). In all 10 patients, reentrant tachycardia was reproducibly induced from the high right atrium with a single premature beat, and initiation of tachycardia could be prevented from the same site by a second premature beat. This second extrastimulus was effective if delivered within a zone that began 10 ms outside of the effective refractory period of the tachycardia-initiating stimulus and averaged 50 ms in width. This zone was termed the "preventive zone." The width of the preventive zone was independent of the initial tachycardia interval and the tachycardia cycle length. Prevention of reentrant tachycardia was always possible with a single atrial extrastimulus, whereas termination of the ongoing tachycardia required at least 2 atrial extrastimuli or stimulation from the right ventricle.

Adolescent↗

PubMed1989

Functional evaluation of sympathetically mediated responses in in vivo lower urinary tract of dogs.

An in vivo procedure for evaluating local effects of alpha-adrenoceptor stimuli on the lower urinary tract was developed in anesthetized dogs. Electrical stimulation of hypogastric nerve at varied frequencies (1, 2, and 4 Hz) and intraarterial (i.a.) administration of an alpha 1-adrenoceptor agonist, phenylephrine (0.3, 1, and 3 micrograms) to the urethra and bladder through the cannulated right external iliac artery caused reproducible frequency- or dose-related increases in intraurethral pressure (IUP). Intrabladder pressure (IBP) was increased by the nerve stimulation but not by i.a. phenylephrine. Acetylcholine (10 micrograms) given i.a. elicited increases in both IUP and IBP. Prazosin (0.1, 1, and 10 micrograms/kg, i.v.) dose-dependently suppressed the urethral contractile responses to the nerve stimulation and i.a. phenylephrine, but it failed to affect the bladder contraction evoked by the nerve stimulation. The results suggest that the urethral contractile responses to hypogastric nerve stimulation as well as i.a. phenylephrine were mediated via alpha 1-adrenoceptors, whereas the IBP increasing effect of hypogastric nerve stimulation was not mediated via alpha 1-adrenoceptors.

Acetylcholine↗

PubMed1994

Kidney mobility during respiration.

Radiotherapy treatment planning needs optimum definition of the target volume in its relative position to normal tissue. The motion of the kidneys during respiration has not been well quantified. They move in a tilted coronal and sagittal plane. Using fast MRI while patients held their breath we quantified the movements of the kidneys. Fourteen patients volunteered for the study. Nine MRI images of the kidneys for one volunteer were done: three in the axial plane (all in deep inspiration) and six in the coronal plane (three in deep inspiration, three in deep expiration). The maximal vertical motion of the superior pole from its end-expiratory to its end-inspiratory position is 39 mm (43 mm for the inferior pole). In deep inspiration or deep expiration the positions of the right and left kidneys appear reproducible. The mean deviation of kidney movement is less than 4 mm in all three dimensions (range, 0-6.9). For tumors close to the kidney, we advocate respiration gated radiation therapy so as to minimize the movement of this very radiosensitive structure.

Adult↗

PubMed1985

Prevention of reentrant tachycardia by single beat or repetitive stimulation.

Eleven patients with an atrioventricular accessory pathway were studied by programmed electrical stimulation to determine if reentrant tachycardia could be prevented by delivery of either a single atrial extrastimulus, applied at a critical time after the tachycardia-initiating stimulus (or stimuli), or a train of stimuli. In all 11 patients, reentrant tachycardia was reproducibly induced from the high right atrium with a single premature beat, and in all patients initiation of tachycardia was prevented from the same site by a second premature beat. This second extrastimulus was effective if delivered within a zone which began 10 ms outside the effective refractory period of the tachycardia-initiating stimulus and averaged 61 ms in width. This was termed the 'preventive zone'. In 7 patients the effect of train stimulation to the high right atrium was studied. In all 7, the results were concordant with those obtained by single-beat stimulation. Any train which achieved single atrial capture within the preventive zone was effective in preventing tachycardia. Prevention was always possible with a single atrial extrastimulus or with single-capture train stimulation, whereas termination of an ongoing tachycardia required at least 2 atrial extrastimuli, or stimulation from the right ventricle.

Adolescent↗

PubMed1991

The impact of antitachycardia pacing with defibrillation.

Chronic recurrent ventricular tachycardia (VT) can be reproducibly terminated by programmed endocardial right ventricular stimulation. However, antitachycardia pacing can be associated with possible acceleration of VT, while frequent episodes of VT and patient discomfort can limit treatment by an implantable cardioverter defibrillator (ICD). The combined use of antitachycardia pacing and the AICD (automatic implantable cardioverter defibrillator) was evaluated in 6 out of 51 patients (age 57 +/- 11 years) in whom the AICD had been implanted because of recurrent VT. In each instance VT could be terminated by temporary overdrive pacing. The interactive mode of VT termination by a pacemaker (Tachylog) as well as by the AICD was assessed after implantation. In the automatic mode, the Tachylog functioned as a bipolar, ventricular inhibited (VVI) device with antitachycardia burst stimulation capability, allowing two to five stimuli at intervals of 260-300 ms and one or two interventions. During follow-up of 47 +/- 24 months, the Tachylog terminated VT reliably 50-505 times per patient. When burst stimulation accelerated VT, termination was achieved by AICD discharge. Thus, drug resistant VT can be terminated by antitachycardia pacing to avoid patient discomfort. In the event of tachycardia acceleration, VT was terminated by the AICD. A universal pacemaker-defibrillator should combine antibradycardia and antitachycardia pacing with back-up cardioversion defibrillation.

Combined Modality Therapy↗

PubMed2001

Accuracy of volumetric measurements after virtual right hepatectomy in potential donors undergoing living adult liver transplantation.

OBJECTIVE: The purpose of this study was to evaluate accuracy for determining the total and lobar liver volumes using a multidetector CT scanner in potential donors undergoing living adult right lobe liver transplantation. SUBJECTS AND METHODS: Fifty-two adult donors underwent CT using a multidetector scanner after IV injection of 180 mL of contrast material. For volumetric determination, portal venous phase images were acquired at 60 sec. Hand-tracing was used to isolate the entire liver, and a curved hepatectomy plane was then identified in a manner simulating the surgical incision. Two observers performed hand-tracing of the entire liver to calculate total liver volume, and of the right lobe to calculate expected graft volume. RESULTS: The mean volume of the entire liver, right lobe, and left lobe was 1807 mL, 990 mL, and 817 mL, respectively, for observer 1, and 1788 mL, 1007 mL, and 781 mL, respectively, for observer 2. There was significant agreement between the two observers in determining total and lobar liver volumes (r = 0.996, 0.977, and 0.965 for total, right lobe, and left lobe volumes, respectively; p< 0.0001). There was no statistically significant difference between the two observers in measuring total or lobar liver volumes (p< 0.0001). There was significant agreement between right lobe volume measured by each observer and graft weight obtained in 14 donors at surgery (r = 0.898 and 0.879, for observers 1 and 2, respectively; p <0.001). CONCLUSION: Total and lobar volume determinations after virtual right hemihepatectomy provides accurate and reproducible information that is critical in selecting potential living liver donors.

Adolescent↗