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Rose A M - - 2000
BACKGROUND: Xenotransplantation of pig hearts to humans could be hampered by the reportedly reduced affinity for digoxin of pig heart. We examined the hypothesis that expression of the individual alpha-subunit isoforms of the sodium pump [Na(+),K(+)-ATPase (NKA)], the receptor for the plant-derived cardiac glycosides, may be responsible for this difference. ...
Zimmer H G - - 2000
Carl Ludwig was the first physiologist to systematically study isolated organs (heart, muscle, kidney, liver, lung). In his Leipzig Physiological Institute, the isolated perfused frog heart preparation was established in 1866 by Elias Cyon. This preparation was subsequently subjected to various modifications, and many important observations were made by scientists ...
Liang Q - - 1999
Chronic alcohol consumption produces alcoholic heart muscle disease (AHMD), a prevalent form of congestive heart failure. Several hypotheses have been proposed to explain the damaging effects of alcohol on the heart, but neither the mechanism nor the ultimate toxin has been established. In this study, we use transgenic overexpression of ...
Willoughby D - - 1999
This paper examines the importance of the calcium-mobilizing inositol phosphate pathway in mediating the effects of FMRFamide and its gene-related neuropeptides on the myogenic heart beat of the pond snail Lymnaea stagnalis. These peptides are encoded on a single exon of the FMRFamide gene and mediate diverse physiological effects in ...
Higuchi M L - - 1999
OBJECTIVE: To analyse the morphological aspects of the extracellular matrix and microcirculation to clarify whether chronic Chagas' cardiopathy (CCC) is an accurate model to study the pathogenesis of idiopathic dilated cardiomyopathy (IDCM). DESIGN: Thick histological myocardial sections were prepared to analyse collagen, and microcirculation was examined during confocal laser and ...
Rajakumar K - - 1999
In a study to compare the clinical diagnostic skills of academic general pediatricians and academic pediatric cardiologists in the evaluation of heart murmurs, a total of 128 patients (aged 1 month to 18 years) newly referred to a university pediatric cardiology clinic were evaluated by one of three general pediatricians ...
Panfilov A V - - 1999
Three-dimensional organization of electrical turbulence that is induced via the phenomenon of spiral breakup is studied in a computer model of the heart, which includes realistic ventricular geometries and cardiac anisotropy. We find filaments of rotors during the turbulence and study their number and length as a function of the ...
Southwood AL - - 1999
Heart rates and diving behavior of leatherback sea turtles (Dermochelys coriacea) were monitored at sea during the internesting interval. Instruments that recorded the electrocardiogram and the depth and duration of dives were deployed on six female leatherback turtles as they laid eggs at Playa Grande, Costa Rica. Turtles dived continually ...
L. Ossevoort,P. Bovendeerd,T. Arts
Introduction The heart is a thickwalled hollow muscular organ. As skeletal muscle, cardiac muscle is able to adapt its structure and geometry to changing loading conditions. Figure 1 : An example of cardiac adaptive processes. Left: An elevated blood pressure causes an increase in wall thickness. Right: Normal heart [2]. ...
Rayburn B K - - 1998
BACKGROUND: The number of patients potentially benefiting from heart transplantation far exceeds the number of hearts available. This has led to an increasing interest in use of hearts from previously unacceptable donors. However, the long-term outcome of such hearts is largely unknown. Research on other parts of the donor process ...
Harvey R P - - 1998
Cardiac looping is a key morphogenetic event in vertebrate heart development. In a complex progression, the linear heart tube adopts a sweeping rightward curvature, establishing an architecture for the multichambered organ it soon becomes. Looping is an asymmetric event, its rightward direction being determined by an embryonic left-right axial pathway. ...
Liebes R - - 1997
Mineral concentrations, copper, zinc-superoxide dismutase and cytochrome c oxidase subunits in human cardiomyopathic heart explants were compared with noncardiomyopathic hearts from autopsy subjects. Iron was reduced in cardiomyopathic hearts, but the zinc:iron ratio was higher in cardiomyopathic hearts. Copper, zinc-superoxide dismutase activity was increased in cardiomyopathic human hearts compared to ...
Levine H J - - 1997
Among mammals, there is an inverse semilogarithmic relation between heart rate and life expectancy. The product of these variables, namely, the number of heart beats/lifetime, should provide a mathematical expression that defines for each species a predetermined number of heart beats in a lifetime. Plots of the calculated number of ...
Chow T W - - 1997
Isolated right heart enlargement of the fetus without cardiac structural abnormalities appears to be associated with growth retardation or abnormal perinatal outcome. We report the outcome of eight fetuses with subjective enlargement of the right heart. All cases were diagnosed antenatally from a standard four-chamber view on an ultrasound scan. ...
Allan L D - - 1996
Cardiac evaluation is an important part of the investigation of a fetus with a diaphragmatic hernia. The heart is displaced by the physical presence of the abdominal contents in the chest, and the flow dynamics within the heart are altered. This can produce secondary diminution of chamber growth, particularly of ...
Chatel D - - 1996
The need for improvement of artificial heart biocompatibility led to the design of new artificial ventricles with biological internal coating and new shapes and sizes. The internal coating of these artificial ventricles is made of a molded single-piece, glutaraldehyde-preserved pericardial sac. The pericardial sac was obtained from the entire intact ...
Cantwell J D - - 1996
A 20-year-old male college sprinter and hurdler was seen for a cardiology assessment because a preseason cardiac evaluation revealed a heart murmur dating back to early childhood. He was asymptomatic.
Thoenes M - - 1996
Recently, a significant activity of inducible nitric oxide synthase (iNOS) has been reported in biopsies from failing hearts due to idiopathic dilated cardiomyopathy (IDC). Thus, a potential pathophysiological role of iNOS in IDC has been stated. In order to investigate, whether iNOS expression is of pathophysiological relevance in human heart ...
Iwanaga M - - 1995
Since people tend to prefer musical tempi ranging from 70 to 100 beats per minute, cyclic physiological response like heart rate is considered on of the factors affected by tempo preference. The present study aimed to examine the relationship between preferred tempi and heart rate. Subjects were instructed to find ...
Wu X - - 1995
Mesoderm induction has been studied in many systems and some of the factors involved have been identified. Although the heart is mesodermal in origin, the molecular basis of heart development is essentially unknown. The Drosophila heart is a simple tubular structure similar to the early heart tube in vertebrates. The ...
Cheng P - - 1995
Cardiolipin is the principal polyglycerophospholipid in the heart. The effect of hypoxia on cardiolipin biosynthesis was investigated in isolated rat hearts perfused in the Langendorff mode. Hearts were pulsed-labeled for 60 min with 0.1 mM [1,(3)-3H]glycerol in Krebs Henseleit buffer saturated with either 95% O2/5% CO2 (control) or 95% N2/5% ...
Schoning P R - - 1995
Gross and microscopic lesions of heart disease in 230 greyhounds were recorded. The most common lesion was endcardiosis, which occurred in 24 (10.4%) of the greyhounds. Other heart lesions included endocardial fibrosis, myocardial necrosis, ossification of the aortic fibrous ring, and abscesses of the right atrium. Although females weighed less ...
Alvarez L - - 1995
The right ventricle was studied in 75 anatomically normal swine hearts, using, in all, nine geometric and volumetric parameters: ventricular-wall thickness, length of the right-ventricular inflow and outflow tracts, and volume of the right-ventricular inflow and outflow tracts. The data for these parameters were compared with previously published patterns for ...
Berntson G G - - 1995
The selection of heart period versus heart rate as a chronotropic metric has been considered from quantitative and statistical perspectives, which have not yielded a universal preference for either metric. In the present paper, we discuss biometric considerations that bear on the selection of the optimal chronotropic metric. Biometric evidence ...
Drysdale T A - - 1994
Cardiac troponin I (troponin Ic) expression is restricted to the heart at all stages of Xenopus development. Whole-mount in situ hybridization and Northern blot analysis indicates that troponin Ic is first expressed in tailbud embryos (stage 28) about the time of the first cytological heart differentiation and about 24 hr ...
van Steenis H G - - 1994
This paper compares two methods to estimate heart rate variability spectra, i.e., the spectrum of counts and the instantaneous heart rate spectrum. Contrary to Fourier techniques based on equidistant sampling of the interbeat intervals, the spectrum of counts and the instantaneous heart rate spectrum are based on non-equidistant sampling: the ...
de Backer G - - 1994
STUDY OBJECTIVE: To identify geographical differences in coronary heart disease (CHD) attack rates in a small urban area and to relate these to indicators of socioeconomic class. DESIGN: CHD attack rates were calculated from data of the Ghent MONICA myocardial infarct register for the period 1983-87. The city of Ghent ...
Hanson C M - - 1994
Heart scores (the arithmetic mean of the QRS durations of the three bipolar limb leads for 10 cycles) and heart weights were determined from five draft type horses and five racing type horses, and evaluated for relationships between heart score and heart size within and between the two different types ...
Shiono M - - 1994
The anatomic constraints and design parameters for a heart prosthesis have not yet been defined in heart transplant recipients (i.e., the population most eligible for total artificial heart implantation). The parameters regarding anatomic constraints were measured in 26 consecutive patients undergoing orthotopic heart transplantation (median body surface area 1.9 m2) ...
Yoshida Y - - 1994
Clinical observations indicate that in heart-lung grafting the heart is less frequently rejected than in heart grafting alone. In addition, our results of allograft experiments indicated that the graft survival period is longer in the former (11.8 +/- 0.8 days versus 6.6 +/- 0.5 days, p < 0.05), suggesting that ...
Smith S C - - 1993
In axolotl embryos homozygous for the cardiac-lethal (c) gene, the heart never begins to beat. Recently, we demonstrated that the c gene affects the heart mesoderm directly, making the latter incapable of responding to normal inductive stimuli. Based on these results, we proposed that a reaction-diffusion mechanism controls the later ...
Griffiths M - - 1993
"Excitement" has often been referred to as the gambler's drug although until recently there was little evidence to substantiate such claims. This study involved the systematic monitoring of the psychophysiology of fruit machine gambling using heart rate measures in 30 adolescent male gamblers. The study was designed to test heart ...
LaFrance S M - - 1993
In the axolotl, Ambystoma mexicanum, a recessive cardiac lethal mutation causes an incomplete differentiation of the myocardium. Mutant hearts do not contain sarcomeric myofibrils nor do they beat. We have previously shown that normal anterior endoderm, medium conditioned by endoderm, or total RNA extracted from endoderm stimulates differentiation of mutant ...
Hoyle C - - 1992
The chick heart tube develops from the fusion of the right and left areas of precardiac mesoderm and in almost all cases loops to the embryo's right-hand side. We have investigated whether any intrinsic difference exists in the right and left areas of precardiac mesoderm, that influences the direction of ...
Shahidi S - - 1992
This paper investigates an alternative approach to the modification of cardiovascular reactivity in healthy Type A adults using contingent (true) and non-contingent (false) heart rate biofeedback. Sixteen Type A and sixteen Type B subjects were either given instructions to compete for heart rate reduction or were given no competitive instructions. ...
Ley R - - 1991
Differences in the magnitude of increases in heart rate during prolonged inhalation of 5% CO2 range from a mean of 25 b/min for a group of eight panic-disorder patients who panicked (Woods, Charney, Goodman, & Heninger, 1988. Archives of General Psychiatry, 45, 43-52) to zero b/min for 16 patients, eight ...
Pauli P - - 1991
In panic disorder bodily sensations appear to play an important role as a trigger for anxiety. In our psychophysiological model of panic attacks we postulate the following vicious circle: individuals with panic attacks perceive even quite small increases in heart rate and interpret these changes as being catastrophic. This elicits ...
Yli-Hankala A - - 1990
The correlation between electroencephalogram (EEG) and instantaneous heart rate was studied in deep isoflurane anaesthesia when the EEG showed a burst-suppression pattern in 15 patients aged 19-39 years. At the onset of EEG burst, the heart rate started to accelerate, and at the onset of suppression it started to decelerate. ...
Dew P A - - 1990
The Utah-100 total artificial heart was initially designed and tested in 1983. General design goals, including improved fit for human application, improved reliability, and elimination of thrombus formation, were identified as improvements over the clinically used Jarvik-7 artificial heart, previously developed at the Institute for Biomedical Engineering, University of Utah. ...
Smith S C - - 1990
We have re-examined some of the factors affecting the induction of heart-forming mesoderm in the axolotl. The formation of functional, rhythmically contracting myocardial tissue was used as an assay. We have found that heart-forming mesoderm is fully induced and capable of completing its developmental repertoire by the end of neurulation. ...
Guo Z G - - 1989
The changes of heart rate (HR) and dP/dtmax elicited by challenging the sensitized heart and by a bolus injection of histamine in the presence of cimetidine were observed. The results showed that cimetidine did not completely inhibit the positive chronotropic effect in cardiac anaphylaxis. The increase in HR elicited by ...
Hatch G M - - 1989
Phosphatidylcholine is the major phospholipid in the mammalian heart. Over 90% of the cardiac phosphatidylcholine is synthesized via the CDP-choline pathway. The rate-limiting step of this pathway is catalyzed by CTP:phosphocholine cytidylyltransferase. Current evidence suggests that phosphatidylcholine biosynthesis in the heart is regulated by the availability of CTP and the ...
Link K M - - 1988
From 3D MR scans, the authors have constructed 2D "silhouettes" that correspond to standard radiographic views of the heart. These images explicitly demonstrate the relationship of the surface anatomy to the internal anatomy of the heart and serve to indicate what chambers contribute to the heart borders seen on radiographs. ...
Wheeldon D R - - 1988
A system that uses a chemical method of cooling has been developed for the storage and transport of heart and heart-lung donor organs. This provides a precisely controlled environmental temperature without the use of ice, with its attendant problems of availability and potential contamination with pathogens. Storage and preservation solutions ...
Szaeó S - - 1988
The authors immunized rabbits with homogenized normal and infarcted human heart muscle. The specific autoantibodies were detected by means of bidimensional complement fixation, passive cutaneous anaphylaxis and double immunodiffusion tests. In the immunological reactions normal and infarcted myocardium extracts containing both sarcoplasmatic and myofibrillar proteins, respectively, were used as antigens. ...
Olson L J - - 1987
In each heart taken from autopsies of 14 men with idiopathic hemochromatosis, the conduction system, atria and 10 sites in the ventricles were histologically graded for stainable iron. Stainable iron was exclusively sarcoplasmic; none was observed in the interstitium. The histologic grade for the same anatomic site varied among hearts ...
Bowman I A - - 1987
Jean-Baptiste Sénac's treatise on the heart is considered a landmark in the history of cardiology. In Traité de la structure du coeur, de son action, et de ses maladies (1749), Sénac dealt systematically with the anatomy, physiology, and pathology of the heart, offering the results of anatomical investigations and postmortem ...
Vasků J - - 1987
The implications of mineralization on the diaphragm of a TAH were highlighted. The problem was discussed from the point of view of time and site of calcifying deposit formation, and individual patterns of calcification as well as the question of the relationship between mineralization processes and thrombogenicity were considered. Attention ...
Galoyan A - - 1986
Data on the endocrine heart--neurosecretory cells of heart, producing coronary-dilatory, metabolically active glycopeptides with physico-chemical and biological properties similar to those of previously discovered cardioactive hypothalamic neurohormones--are summarized. Heart hormones participate in both local and distant regulation of heart metabolism and function. Formation and action of these heart hormones is ...
Yada T - - 1985
Double-hearted embryos were produced by whole-embryo culture of chick embryos which were microsurgically cut through the tissue of the anterior intestinal portal at the 1- to 6-somite developmental stage, at the time when the cardiac primordia have not yet fused in the bulboventricular region. The cultured embryos were removed from ...
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