Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| flow through collapsible tubes at high reynolds numbers. | the pressure-flow relationships of collapsible tubes were studied utilizing the starling resistor model. reynolds numbers much higher than previously reported were used to simulate high cardiac output states. alterations which occur in vivo, including longitudinal tension, stretch, tubing diameter, length, and outflow resistance were also simulated and systematically investigated. the pressure-flow curves showed an initial rising phase, a plateau phase, as well as a late-rising phase which has n ... | 1981 | 7273367 |
| effects of isolated interventricular septal ischemia on global and segmental function of the canine right and left ventricle. | the effects of isolated septal artery ligation wee studied in 17 dogs. contraction of the interventricular septum (ivs) and the free walls of both ventricles was measured by implanting ultrasonic crystals. global ventricular function was assessed by starling function curves. following septal artery ligation, ivs shortening was immediately replaced by systolic lengthening. thirty minutes after septal artery ligation, the right ventricular (rv) stroke work (sw) was significantly depressed at end-d ... | 1981 | 7282511 |
| protein vs electrolytes and all of the starling forces. | hemodilution-induced reductions of the intravascular protein concentration in patients and experimental animals with intact capillaries do not lead to pulmonary edema, despite significant increases in the amount of extravascular water in the systemic interstitial space. the protective factors are a drop in the extravascular concentration of protein, a rise in interstitial tissue pressure, and an increase in lymph flow. if the capillary endothelium is damaged, protein leaks into the extravascular ... | 1981 | 7283703 |
| transcapillary refill in hemorrhage and shock. | moderate or major hemorrhage leads to diminished cardiac output and to increased total peripheral resistance. these cannot be corrected fully until blood volume is restored, which, in the absence of therapy, requires the movement of fluid and of protein from the interstitium into the capillaries. this movement appears mediated entirely by changes in the starling forces, dominated in the first phase by a fall in capillary hydrostatic pressure, which promotes a rapid shift of protein-free fluid fr ... | 1981 | 7283706 |
| hypoxic vasoconstriction and fluid filtration in pig lungs. | we have studied the effect of hypoxia [inspired partial pressure of o2 (po2) 50 mmhg] on the relationships among pulmonary blood flow, pulmonary arterial pressure, and fluid filtration rates in isolated blood-perfused pig lungs. our results indicate that hypoxia constricted the vasculature in a manner that caused a parallel shift of the pressure-flow curve to higher pressures. during normoxia, filtration rate was zero at flows less than 1.5 1/min but increased with increases in blood flow above ... | 1981 | 7298444 |
| subcutaneous starling forces in the unanaesthetized guinea-pig fetus with indwelling catheters. | we placed capsules in fetal guinea-pigs for measuring the hydrostatic pressure of the interstitial fluid and for collecting samples of interstitial fluid. the vitelline artery and vein were cannulated to measure blood pressures. plasma colloid osmotic pressure (mmhg) and total protein concentration (g/100 ml) were measured in samples taken from other adult and fetal guinea-pigs and were found to be related by colloid osmotic pressure = 0.16 + 2.32 x protein concentration. the colloid osmotic pr ... | 1981 | 7299103 |
| shortening fraction: its dependence on the starling mechanism. | the influence of increasing muscle length (ml) from l0 to 15 to 20% of l0 and calcium concentration (ca2+) from 1.34 to 10 mmol . litre-1 on shortening fraction has been analysed in cat papillary muscles. shortening fraction was calculated by dividing the amount of shortening by the muscle length at which that shortening occurred. when the muscle shortened at contrast total load, increasing muscle length from approximately or equal to l0 to approximately or equal to 15% above l0, increased the s ... | 1981 | 7307033 |
| interstitial fluid volume, colloid osmotic and hydrostatic pressures in rat skeletal muscle. effect of hypoproteinemia. | colloid osmotic pressures in plasma (copp) and interstitial fluid (copi), interstitial fluid pressure (pi) as well as interstitial fluid volume (ifv) was measured in rat skeletal muscle during development of hypoproteinemia. the hypoproteinemia was induced with intraperitoneal injections of aminonucleoside puromucin causing a renal lesion similar to that in human nephrotic syndrome with renal loss of plasma protein and subsequent fall in copp. when copp fell from control values (about 20 mmhg) t ... | 1981 | 7315408 |
| cardiac effects of splanchnic and non-splanchnic blood volume redistribution during aortic occlusions in dogs. | translocation of blood from the lower body dilates the left ventricle during occlusion of the descending thoracic aorta and by increased activation of the frank-starling mechanism, stroke volume is maintained despite raised aortic blood pressure. the contributions from the splanchnic and non-splanchnic blood volumes to the left ventricular dilation were examined by ultrasonic measurements of myocardial chord length (mcl) in atropinized open-chest dogs. end-diastolic mcl rose by 2.5 +/- 0.9% duri ... | 1981 | 7315445 |
| [echocardiographic study of left ventricular performance during sitting bicycle exercise (author's transl)]. | twelve healthy volunteers, mean age 25.4 +/- 4.18 years, performed sitting bicycle ergometer graded exercise to exhaustion. recordings of left ventricular echocardiographic dimension, heart rate, arterial blood pressure, were obtained at rest and at two minutes intervals during exercise and recovery. echocardiographic tracings were digitized and the values of three complexes were combined and means determined for the overall analysis. heart rate increased from 76.92 +/- 15.09 to 154.91 +/- 12.13 ... | 1981 | 7327323 |
| influence of alterations in starling forces on visceral pleural fluid movement. | the influence of alterations in hydrostatic and oncotic pressure gradients on fluid movement across the visceral pleura was examined in 16 spontaneously breathing anesthetized dogs. the left lung was enclosed in a water-impermeable polyethylene membrane, creating a visceral pleural space; visceral fluid movement was determined as the formation or reabsorption of fluid in this space. aortic, pulmonary arterial, right and left atrial, and pleural pressures were monitored; oncotic pressure was calc ... | 1981 | 7327968 |
| pleural liquid pressure over the interlobar mediastinal and diaphragmatic surfaces of the lung. | pleural liquid pressure (pliq) was measured in the interlobar fissures and over the mediastinal apical, cardiac and diaphragmatic surface. when compared to costal values, pliq was more subatmospheric over the cardiac region at all lung heights by about 5 cm h2o so that a costo-hilar gradient down the interlobar fissures of about 0.7 cm h2o/cm was found. no differences were found for other surfaces. cardiac values, unlike costal ones, became more subatmospheric on increasing ventilation and heart ... | 1981 | 7330492 |
| histamine receptors in the bronchial musculature and vasculature of the dog. | participation of histamine h1- and h2-receptors in the bronchial musculature and vasculature of the dog was investigated by using the method for evaluating airway responses. a peristaltic pump and a starling pneumatic resistance were used for a constant pressure perfusion. dogs given 0.1 - 10 micrograms histamine by a close intraarterial injection showed increases in ventilation overflow (bronchoconstriction) and in blood flow (bronchial vasodilatation) in a dose-dependent manner. the bronchocon ... | 1981 | 7334453 |
| effects of active shortening on tension development of rabbit papillary muscle. | duration and intensity of force development have been shown to be less during active muscle shortening than during isometric contraction. the purpose of this study was to compare force developed during controlled shortening with that predicted by the frank-starling relation. paillary muscles from the right ventricles of rabbits were arranged for isometric tension recording, and isometric contractions were recorded at several lengths. the muscles were then permitted to shorten at velocities of 0. ... | 1980 | 7356035 |
| control of fetal cardiac output during changes in blood volume. | changes in cardiac output (qco), heart rate, right atrial pressure, (pra), and mean systemic pressure (pms) in response to blood volume changes were measured in chronically prepared fetal sheep. with a 10% decrease in blood volume, fetal cardiac output, measured with the microsphere technique, decreased significantly from 592 +/- 28 to 471 +/- 32 ml . min-1 . kg-1. heart rate changed little from control animals (163 +/- 5) to those with decreased volume (161 +/- 10 beats/min). right atrial press ... | 1980 | 7356036 |
| unit recordings from a new auditory area in the frontal neostriatum of the awake starling (sturnus vulgaris). | auditory units were recorded from a restricted region of the frontal neostriatum of the awake starling. this area (field ga) was located latero-dorsal from the nucleus basalis and more closely associated with the caudal regions of the thalamo-frontal tract. most units (46%) showed on-excitation to pure tones and white noise stimuli. no well-defined sustained firing was seen, but 15% of the units showed a weak type of excitation which outlasted the stimulus (long-lasting response). tuning curves ... | 1980 | 7363972 |
| measurement of frequency discrimination in the starling (sturnus vulgaris) by conditioning of heart rate. | 1980 | 7374787 | |
| mechanism of hemodynamic responses to occlusion of the descending thoracic aorta. | to examine left ventricular responses to aortic occlusion, changes in end-diastolic volume (edv) and end-systolic volume (esv) were estimated by ultrasonic recordings of myocardial distances in atropinized open-chest dogs. during aortic occlusion edv and esv increased equally, systolic left ventricular pressure (lvp) rose by 86 +/- 8 mmhg, and blood flow more than doubled in the superior vena cava and fell by 90% in the inferior vena cava. during combined occlusion of aorta and inferior vena cav ... | 1980 | 7377312 |
| calcitonin stimulation of urine flow and sodium excretion in the starling. | renal effects of synthetic salmon calcitonin (ct) were examined in normal and parathyroidectomized (ptx) starlings, sturnus vulgaris. standard clearance studies were performed. anesthetized birds were infused with [14c]-inulin in 2.5% mannitol containing either 0.25% gelatin alone as a control, or gelatin plus ct (2 iu ct/h; armour). in intact starlings, ct significantly increased urine flow and relative clearance of sodium (cna/cin). cca/cin was significantly elevated only 40 min after start of ... | 1980 | 7377379 |
| transcapillary starling forces using membrane osmometry. | membrane osmometry was used to estimate the four transcapillary starling pressures in subcutaneous tissue of rats, guinea pigs, and dogs. isolated subcutaneous tissue samples were either placed on a large-pore or small-pore osmometer that measured the interstitial fluid pressure (pif) and the difference between the interstitial fluid pressure and the interstitial protein osmotic pressure (pif-pi if), respectively. the colloid osmotic pressure of the interstitial fluid (pi if) was obtained from t ... | 1980 | 7386647 |
| fat of the wild avian filarial nematode chandlerella quiscali (onchocercidae: filarioidea) in the domestic chicken. | chandlerella quiscali is a filarial nematode parasitizing the brain of the common grackle (quiscalus quiscula versicolor), blue jay (cyanocitta cristata bromia), brown-headed cowbird (molothrus ater ater), and starling (sturnus vulgaris). filarial infections of many wild bird species are common but natural infections of domestic fowl are rare. the habits of many wild birds commonly bring them in close association with domestic poultry. because of the high prevalence of c. quiscali in grackles (9 ... | 1980 | 7393850 |
| the effect of increasing preload on ventricular output and ejection in man. limitations of the frank-starling mechanism. | 1980 | 7398014 | |
| effects of calcium on the sarcomere length-tension relation in rat cardiac muscle. implications for the frank-starling mechanism. | 1980 | 7408137 | |
| collyricloides massanae vaucher, 1969, in a starling (sturnus vulgaris l.) in the netherlands. | collyricloides massanae (trematoda: collyriclidae) is described from cysts in the wall of the small intestine of a starling (sturnus vulgaris l.) in the netherlands. the original descriptin was from a yellow necked mouse, apodemus flavicollis (melchior), so this is the first record of the species in birds. | 1980 | 7410811 |
| hemodynamics in patients with severe toxemia during labor and delivery. | three patients with severe pre-eclampsia-toxemia were studied with thermodilution tip pulmonary artery catheters. all patients were delivered by cesarean section with general anesthesia and endotracheal intubation. the left ventricular stroke work indices (lvswi) of these patients were higher than those of normal nonpregnant subjects. there was no evidence of myocardial depression in terms of either cardiac index or the lvswi-pulmonary capillary wedge pressure (frank-starling) relationship. pulm ... | 1980 | 7416216 |
| an analysis of the mechanical disadvantage of myocardial infarction in the canine left ventricle. | an isotropic, initially spherical, membrane model of the infarcted ventricle satisfactorily predicts ventricular function in the infarcted heart when compared to clinical information and available ventricular models of higher complexity. computations based on finite element solutions of this membrane model yield end-diastolic and end-systolic pressure-volume curves, from which ventricular function curves are calculated, for infarcts of varying size and material properties. these computations ind ... | 1980 | 7418131 |
| comparison between lung fluid filtration rate and measured starling forces after hemorrhagic and endotoxic shock. | the measurement of pulmonary vascular pressure and plasma oncotic pressure (pi p) is reported to be useful for predicting excess fluid transport across the pulmonary microcirculation in the critically ill. however, interpretation of change in these forces must take into consideration the compensatory changes in the other starling forces, particularly interstitial oncotic pressure (pi i) and the permeability characteristics of the membrane. we calculated pulmonary microvascular pressure pmv, pi p ... | 1980 | 7420495 |
| alterations of myocardial function during early stages of mild experimental ischemia in dogs determined by left ventricular pressure-wall thickness loop. | alternations of regional left ventricular myocardial function immediately after coronary artery branch ligation as related to the total left ventricular function were determined by utilizing left ventricular pressure-wall thickness loop in 6 anesthetized open-chest dogs. end-diastolic wall thickness was decreased immediately from 11.54+/-0.50 mm (standard error of the mean) of control to 10.99+/-0.50 mm in 5 to 10 min after ligation (p<0.05), while regional myocardial work calculated as the loop ... | 1980 | 7420735 |
| reversal of ischemic damage with amino acid substrate enhancement during reperfusion. | twenty dogs underwent 15 minutes of normothermic ischemic arrest and 30 minutes of reperfusion while on cardiopulmonary bypass. in 10 control dogs, the reperfusate blood was not modified. in 10 other dogs, the aorta was reclamped and the heart reperfused for 5 minutes with blood containing l-glutamate (0.026m). we measured coronary blood flow (microspheres), left ventricular (lv) metabolism [o2 content, adenosine triphosphate (atp)], lv compliance (intraventricular balloon), and lv performance ( ... | 1980 | 7434210 |
| innervation of the parathyroid in the european starling (sturnus vulgaris). | anatomical studies were conducted to characterize the source, type, and distribution of parathyroid gland innervation in european starlings. denervation experiments demonstrated that the parathyroid glands and adjacent carotid bodies are innervated by nerve fibers originating in the nodose ganglion of the vagus nerve. in the parathyroid parenchyma, these fibers terminate adjacent to chief cells or near vascular smooth muscle. vagal fibers also form synapses with catecholamine-containing glomus c ... | 1980 | 7452732 |
| effect of saline expansion on peritubule capillary pressures and reabsorption. | the effect of extracellular volume expansion on transcapillary starling forces, capillary uptake, and the reabsorption coefficient in the peritubule microcirculation of the dog kidney was examined. micropuncture techniques were used to obtain measurement before and after 4% body wt expansion with isotonic saline. extracellular volume expansion significantly changed all starling pressures and capillary uptake. efferent arteriolar oncotic pressure, interstitial oncotic pressure, and capillary upta ... | 1981 | 7468796 |
| the effect of duration of exposure to short days on the gonadal response to long days in male starlings (sturnus vulgaris). | photorefractory male starlings (sturnus vulgaris) were transferred from a photoperiodic schedule of 18 h light:6 h dark to 8 h light:16 h dark for 2, 4, 6 or 10 weeks, and then photostimulated by exposure to 18 h light:6 h dark. testicular dimensions were measured at regular intervals by laparotomy. there was no change in testicular volume in birds photostimulated after 2 weeks under a photoperiod of 8 h light:16 h dark, but a cycle of testicular growth followed by regression occurred in the oth ... | 1995 | 7473410 |
| studies of hypoxemic/reoxygenation injury: without aortic clamping. ii. evidence for reoxygenation damage. | this study tested the hypothesis that the developing heart is susceptible to oxygen-mediated damage after reintroduction of molecular oxygen and that this "unintended" reoxygenation injury causes lipid peroxidation and functional depression that may contribute to perioperative cardiac dysfunction. among 49 duroc-yorkshire piglets (2 to 3 weeks old, 3 to 5 kg) 15 control studies were done without hypoxemia to test the effects of the surgical preparation (n = 10) and 60 minutes of cardiopulmonary ... | 1995 | 7475168 |
| studies of hypoxemic/reoxygenation injury: without aortic clamping. iv. role of the iron-catalyzed pathway: deferoxamine. | this study tests the hypothesis that an iron chelator, deferoxamine, can reduce oxygen-mediated myocardial injury and avoid myocardial dysfunction after cardiopulmonary bypass by its action on the iron-catalyzed haber-weiss pathway. twenty-one immature 2- to 3-week-old piglets were placed on cardiopulmonary bypass for 120 minutes, and five piglets served as biochemical controls without cardiopulmonary bypass. five piglets underwent cardiopulmonary bypass without hypoxemia (cardiopulmonary bypass ... | 1995 | 7475170 |
| studies of hypoxemic/reoxygenation injury: without aortic clamping. ix. importance of avoiding perioperative hyperoxemia in the setting of previous cyanosis. | this study of an in vivo infantile piglet model of compensated hypoxemia tests the hypothesis that reoxygenation on hyperoxemic cardiopulmonary bypass produces oxygen-mediated myocardial injury that can be limited by normoxemic management of cardiopulmonary bypass and the interval after cardiopulmonary bypass. twenty-five immature piglets (< 3 weeks old) were placed on 120 minutes of cardiopulmonary bypass and five piglets served as a biochemical control group without cardiopulmonary bypass. fiv ... | 1995 | 7475175 |
| discrimination training in a go/nogo-procedure alters the 2-deoxyglucose pattern in the starling's forebrain. | european starling's (sturnus vulgaris l.) were used to measure differences in the glucose metabolism in the auditory forebrain between birds performing an auditory discrimination task and birds habituated to the same acoustic stimuli. one group (n = 5) of individuals was trained in an operant go/nogo-procedure to report 1-khz tone signals in a background of 4-khz stimuli. the other group (n = 5) was habituated to the experimental set-up and to the same sequence of tones presented to the trained ... | 1995 | 7552331 |
| pressure-flow relationships in in vitro model of compartment syndrome. | compartment syndrome is a condition in which an increase in intramuscular pressure decreases blood flow to skeletal muscle. according to the starling resistor (i.e., vascular waterfall) model of blood flow, the decrease in flow could occur through an increase in arterial resistance (rart) or an increase in the critical closing pressure (pcrit). to determine which explains the decrease in flow, we pump perfused a canine gastrocnemius muscle placed within an airtight box, controlled box pressures ... | 1995 | 7559222 |
| angiotensin ii and cardiovascular regulation in a freshwater teleost, anguilla rostrata lesueur. | cardiac output (co), dorsal aortic blood flow (bfda) and blood pressure (pda), and heart rate (hr) were recorded simultaneously in conscious freshwater eels. physiological doses of [asn1,val5]angiotensin ii (ang ii; 25-150 ng/kg iv) were used to investigate its effects on the blood flow [co, bfda, and estimated branchial shunting (bs)] and systemic vascular resistance (rsys) components of the pressor response and possible mechanism(s) of action. co was increased mainly by an elevated stroke volu ... | 1995 | 7573576 |
| the influence of isotonic exercise on cardiac hypertrophy in arterial hypertension: impact on cardiac function and on the capacity for aerobic work. | intense physical training through isotonic exercises has controversial effects in individuals with moderate to severe hypertension. in this study, normotensive wistar rats and rats with renovascular hypertension (goldblatt ii) were subjected to intense physical exercise involving two 50-min swimming sessions per day for a period of 12 weeks. at the end of the study, we evaluated the effect of training on arterial pressure, the capacity for aerobic work and cardiac function. our results demonstra ... | 1995 | 7584822 |
| the role of the left atrial appendage. a volume loading study in open-chest dogs. | although the left atrial appendage has a quite unique structure, its function remains unclear. to clarify the function of the left atrial appendage, changes in its anteroposterior, transverse and longitudinal dimensions, and in the anteroposterior dimension of the left atrial body were measured by a sonomicrometer during volume loading in open chest dogs. in the control state, fractional shortening of the transverse dimension of the appendage was greater than that of the atrial body. after dextr ... | 1995 | 7596042 |
| a model of human microvascular exchange. | a compartmental model consisting of the circulation, a general interstitium, and the lymphatics, is formulated to describe the transport and distribution of fluid and plasma proteins (albumin) in the human microvascular exchange system. transcapillary mass exchange is assumed to occur via a coupled starling mechanism. unknown or poorly quantified model parameters are estimated by statistical fitting of simulation predictions to five different sets of experimental data. the data consist of steady ... | 1995 | 7603353 |
| an excitation-pattern model for the starling (sturnus vulgaris). | this paper develops and tests an excitation-pattern model for the starling. like excitation-pattern models for humans [e.g., zwicker, acustica 6, 365-381 (1956); florentine and buus, j. acoust. soc. am. 70, 1646-1654 (1981)], the model for starlings provides a unified account of a large body of data. the foundation of the model is a critical-band scale, which is derived as an equal-distance scale according to a cochlear-map function. the cochlear-map function is determined as a best-fitting func ... | 1995 | 7608390 |
| peritoneal fluid and tracer albumin kinetics in the rat. effects of increases in intraperitoneal hydrostatic pressure. | to study the peritoneal fluid loss rate, the clearance (ci) of radioactive tracer albumin (risa) eliminated from the peritoneal cavity (pc), as well as the peritoneal-to-plasma risa clearance (ci-->p) during acute peritoneal dialysis (pd) at large elevations in intraperitoneal hydrostatic pressure (ipp). | 1995 | 7612731 |
| critical bands and critical-ratio bandwidth in the european starling. | critical bands (cb) and critical-ratio (cr) bandwidth were determined in five european starlings (sturnus vulgaris) using a go/nogo procedure and the method of constant stimuli. test-tone frequencies were 1, 2, 4, and 6.3 khz. critical ratios were independent of the level of the white noise masker. the lowest cr of 21.8 db was found at 1 khz, and the cr monotonically increased on average by 2.3 db per octave. cr-bandwidths at a masker spectrum level of 41 db were 151, 191, 437, and 501 hz at 1, ... | 1995 | 7642449 |
| effects of heart rate on left atrial contractile performance and left ventricular filling during atrial systole in dogs. | left ventricular (lv) diastolic filling and left atrial (la) contribution have been investigated in patients with heart disease. however, many of these studies were not conducted at a constant heart rate, and the effects of heart rate remain unclear. the purpose of this study was to clarify the effects of the heart rate on left atrial contractile performance and left ventricular filling during atrial systole. the changes in la and lv dimensions and pulmonary venous (pv) flow were determined in 9 ... | 1995 | 7650843 |
| age-related changes in rat interstitial matrix hydration and serum proteins. | measurements of effects of age-related changes on loose connective tissue protein concentrations and water are lacking. tissue hydration is an important determinant of tissue protein diffusion coefficients and hydraulic conductivity. sprague-dawley rats (ages 11, 30, 57, and 89 wk) were anesthetized. blood and mesenteric tissue samples were taken. tissue water content was determined by microgravimetric technique. protein content was determined by electrophoresis. tissue hydration decreased 18% b ... | 1995 | 7671020 |
| the ventricular-synchronous, skeletal-muscle ventricle: preliminary feasibility studies. | the two requirements for the optimal use of skeletal muscle wrapped around a pouch used to pump blood are:(1) a low pouch diastolic pressure (to assure a high muscle capillary blood flow; and (2) a high pouch precontraction pressure (pcp) (to assure a forceful muscle contraction). both requirements are satisfied with the pumping method described herein. this new type of skeletal-muscle ventricle (smv) consists of a rectus abdominis muscle wrapped around a pouch connected to the left ventricular ... | 1993 | 7686661 |
| [cardiodynamics and cardiac pump function in hyperthermia]. | disorders of myocardial pumping function were shown in experimental dogs under hyperthermia. end-systolic, end-diastolic and stroke volume were decreased under those conditions. the effectiveness of frank-starling mechanism was reduced in severe hyperthermia. | 1993 | 7690614 |
| sexual dimorphism in the volume of song control nuclei in european starlings: assessment by a nissl stain and autoradiography for muscarinic cholinergic receptors. | previous studies have found that the volume of several song control nuclei is larger in male songbirds than in female songbirds. the degree of this volumetric sex difference within a given species appears to be systematically related to the degree of the behavioral sex difference. the largest volumetric differences have been reported in species in which the male sings and the female sings little, if at all, and the smallest sex differences in volume have been reported in species in which males a ... | 1993 | 7691901 |
| general pattern and morphological specializations of the avian cochlea. | in different bird species, there is a common pattern in the hair-cell morphology and innervation of the basilar papilla; the absolute values, however, are species-specific. in the barn-owl papilla, an extreme being case, the basal high-frequency part of the papilla is greatly expanded. in this behaviorally most important frequency range of the barn owl, the number of afferent nerve terminals to neural hair cells is extensively increased. instead of about 2 afferent terminals as in other species, ... | 1994 | 7701304 |
| regulation of the structural remodelling of the myocardium: from hypertrophy to heart failure. | the framingham heart study has shown that arterial hypertension is the major aetiological factor for the development of heart failure. in the presence of heart failure, various regulatory systems may be operative. these include the frank-starling mechanism, the neurohormonal system, regulation of cardiac growth and peripheral oxygen delivery. recently, the interrelationship of the neuroendocrine system and cardiac growth has been examined. in the pressure or volume overloaded heart, growth of th ... | 1994 | 7713113 |
| a comparison of the responses to gonadotrophin-releasing hormone of adult and juvenile, and photosensitive and photorefractory european starlings, sturnus vulgaris. | the reproductive system of juvenile european starlings appears to be similar to that of photorefractory adults, yet the increase in plasma luteinizing hormone (lh) in juveniles in response to gonadotrophin-releasing hormone (gnrh) is much less than that of photorefractory adults. to investigate this apparent anomaly, the effects of age, reproductive state, and sex on the increase in plasma lh concentration in response to im injections of gnrh were investigated. the results show that photorefract ... | 1995 | 7713378 |
| the size of the heart. | the size of the heart varies very little over a whole range of normal physiological activities. physiologists, in animals and man, measure changes in cardiac output and heart volumes during exercise. cardiac output can increase 5, 6, or 7 times in athletes but the stroke volume never more than doubles, the end-diastolic volume increases only by about 50% and the end-systolic (residual) volume decreases by the same amount; the heart rate increases about two and a half times in the untrained to 5 ... | 1994 | 7742481 |
| myocardial function in septic sheep. | there is an ongoing discussion whether the heart is the primary target organ responsible for the development of cardiovascular failure during septic shock as well as its onset. we tried to study the reaction of the heart to sepsis in the early phase of 8 h, using a sublethal model of sepsis in six awake cross-bred austrian mountain sheep. sepsis was induced by infusion of a live escherichia coli suspension at a dose of 5 x 10(7) colony-forming units per kg body weight over 8 h. standard hemodyna ... | 1994 | 7743334 |
| pulmonary capillary wedge pressure estimates of left ventricular preload are inaccurate in endotoxin shock: contribution of starling resistor forces to septic pulmonary hypertension. | we tested the hypothesis that starling resistor forces play a significant role in the increase in pulmonary vascular resistance during endotoxin shock. anesthetized pigs (n = 9) were given escherichia coli endotoxin (etx; .5 mg/kg intravenously over 30 min). mean pulmonary arterial pressure (mpap) and pulmonary capillary wedge pressure (pcwp) were recorded through a swan-ganz catheter. pulmonary capillary pressure (pc) was obtained from the analysis of the transient pulmonary artery pressure dec ... | 1994 | 7743360 |
| temporal modulation transfer functions in the european starling (sturnus vulgaris): ii. responses of auditory-nerve fibres. | the temporal resolution of cochlear-nerve fibres in the european starling was determined with sinusoidally amplitude-modulated noise stimuli similar to those previously used in a psychoacoustic study in this species (klump and okanoya, 1991). temporal modulation transfer curves (tmtfs) were constructed for cochlear afferents allowing a direct comparison with the starling's behavioural performance. on average, the neuron's detection of modulation was less sensitive than that obtained in the behav ... | 1995 | 7744716 |
| effects of hypertonic-hyperoncotic infusion on the human atrial natriuretic factor in a standardized clinical trial. | hypertonic-hyperoncotic solutions (hht) are presently being utilized to resuscitate patients in shock. however, so far, the effects of hht on human atrial natriuretic factor (hanf) have not yet been investigated in a clinical trial. the effects of hht on hanf were studied in a standardized preoperative and clinical setting in patients undergoing aneurysmectomy. twenty-three conscious patients were included in two groups: 11 hht and 12 hes (hht: 7.5% nacl/10% hes 200; hes: .9% nacl/10% hes 200). ... | 1995 | 7749942 |
| the role of platelet-activating factor in lipopolysaccharide-induced myocardial depression in guinea pigs. | to determine if platelet-activating factor (paf) is a key mediator of lipopolysaccharide (lps)-induced myocardial depression in guinea pigs. | 1995 | 7757142 |
| [design, manufacturing, and testing of a pulsatile ventricular assist device]. | to describe the design of a ventricular assist device (vad), its manufacturing and testing. | 1994 | 7778999 |
| design, manufacturing, and testing of a paracorporeal pulsatile ventricular assist device: são paulo heart institute vad. | this paper describes the design of a ventricular assist device (vad), its manufacturing, and testing. the vad presented is pulsatile, with a free-floating membrane, smooth internal surfaces, and pericardial valves. it comprehends also a pneumatic driving unit capable of operating in the "full to empty," ekg synchronized or asynchronous modes. in vitro tests were performed to assess its mechanical durability, hydrodynamic performance, and hemolysis. to optimize cannulas and implant techniques, we ... | 1995 | 7779018 |
| reflective organelles in the anterior pigment epithelium of the iris of the european starling sturnus vulgaris. | the ultrastructure and chemical composition of reflective organelles in the anterior pigment epithelium of the iris of the european starling sturnus vulgaris were examined. the reflective organelles produced a diffuse white reflectance at the iris mid-section which was visible only when the stroma was removed. the pigment granules were clear, angular, and birefringent under the light microscope. in electron micrographs the granules were irregular in shape and density, sometimes crystalline in ap ... | 1995 | 7781036 |
| osmotic compression of single cardiac myocytes eliminates the reduction in ca2+ sensitivity of tension at short sarcomere length. | according to the frank-starling relation, cardiac output varies as a function of end-diastolic volume of the ventricle. the cellular basis of the relation is thought to involve length-dependent variations in ca2+ sensitivity of tension; ie, as sarcomere length is increased in cardiac muscle, ca2+ sensitivity of tension also increases. one possible explanation for this effect is that the decrease in myocyte diameter as muscle length is increased reduces the lateral spacing between thick and thin ... | 1995 | 7788878 |
| the cardiac structure-function relationship and the renin-angiotensin-aldosterone system in hypertension and heart failure. | according to the framingham study, arterial hypertension and coronary artery disease are the major etiologic factors in the development of heart failure. regulatory systems that may affect heart failure include the frank-starling mechanism, neurohormonal responses, cardiac growth and peripheral oxygen delivery. recently, the interrelationship between the neuroendocrine system and cardiac growth has aroused much interest. in the pressure- or volume-overloaded heart, hypertrophic growth of the myo ... | 1994 | 7827369 |
| starling resistor vs. distensible vessel models for embolic pulmonary hypertension. | we investigated whether the starling resistor model (mitzner et al. j. appl. physiol. 51: 1065-1071, 1981) or a distensible vessel model (haworth et al. j. appl. physiol. 70: 15-26, 1991) best describes pulmonary vascular pressure-flow (q) relationships in embolic pulmonary hypertension. mean pulmonary arterial pressure (ppa)-q plots at constant left atrial pressure (pla) and ppa-pla plots at constant q were investigated in seven dogs before and after 500-micron glass bead pulmonary embolism. em ... | 1995 | 7864209 |
| a radioimmunoassay for recombinant-derived chicken prolactin suitable for the measurement of prolactin in other avian species. | a homologous radioimmunoassay for chicken prolactin is described. the assay is based on recombinant-derived chicken prolactin that has been used to raise an antibody and produce 125i-labeled tracer and assay standards. the radioimmunoassay measures a minimum of 0.03 +/- 0.01 ng of the recombinant prolactin with 50% displacement of binding by 0.6 +/- 0.1 ng. chicken plasma and pituitary immunoreactivity dilute in parallel with the standard curve. the mean (+/- se) concentrations of plasma prolact ... | 1994 | 7883142 |
| starling pressures in the human arm and their alteration in postmastectomy oedema. | 1. surgery and radiotherapy to axillary lymph nodes during breast cancer treatment is often followed, commonly years later, by chronic postmastectomy oedema (pmo). pmo is considered a 'high protein' oedema due to reduced axillary lymph drainage. since oedema formation also depends on fluid input (capillary filtration), we studied the starling pressures in the affected and contralateral arm. colloid osmotic pressure was measured in patient serum (pi p) and interstitial fluid (pi i). subcutis flui ... | 1994 | 7932226 |
| cyclophosphamide effects on immune function of european starlings. | we developed and tested a battery of immune function assays on adult european starlings (sturnus vulgaris) exposed to the immunotoxicant cyclophosphamide (cy). starlings were injected intraperitoneally for three consecutive days with saline or 20 mg/kg cy. cyclophosphamide did not affect body mass or packed cell volume. however, spleen to body mass ratios and the number of viable spleen cells were lower in cy-treated birds when compared to controls. peripheral white blood cell numbers were reduc ... | 1994 | 7933273 |
| sex differences in the volume of avian song control nuclei: comparative studies and the issue of brain nucleus delineation. | two goals of research on neural sex differences are to establish the behavioral function of such sex differences and to identify precisely what features differ between males and females. comparative studies of sex differences in the volume of brain nuclei within the songbird vocal control circuit provide one way to address these goals. informative comparisons can be either inter-specific or intra-specific. inter-specific comparisons of species within the songbird suborder allow one to establish ... | 1994 | 7938349 |
| increased vascular resistance with hemoglobin-based oxygen carriers. | to compare the effects of resuscitation with hemoglobin-based oxygen-carriers and conventional resuscitation fluids on hemodynamics, oxygen transport, and oxygen consumption in an animal model of the use of these fluids in the treatment of hemorrhagic shock. | 1994 | 7994360 |
| chronic alterations in cardiac mechanics after fetal closed heart operation. | pulmonary artery banding was performed in 8 fetal sheep at 125 days' gestation to evaluate the feasibility of fetal closed cardiac operation. at 135 days' gestation, the fetuses were delivered and the cardiac mechanics were evaluated using a modified langendorff isolated heart preparation. two of the 8 fetuses aborted spontaneously 2 and 7 days after operation. six fetuses (75%) survived the 10 days after delivery. the left ventricular cardiac mechanics in the banded fetuses (group i) were compa ... | 1994 | 8010781 |
| an analysis of the interaction between interstitial plasma protein, interstitial flow, and fenestral filtration and its application to synovium. | an analysis of the interstitial flow of a protein solution is presented, based on physical interactions with extracellular matrix biopolymers. previous models were extended by incorporation of three features--(a) interstitial osmotic reflection coefficients and attendant partial molecular sieving, (b) the effect of solute exclusion on apparent intramatrix fluid viscosity, and (c) the effect of discrete capillary porosity on near-pore oncotic and hydraulic gradients. the principles were applied t ... | 1994 | 8022316 |
| experimental transmission of crimean-congo hemorrhagic fever virus by west african wild ground-feeding birds to hyalomma marginatum rufipes ticks. | hyalomma (h.) marginatum rufipes ticks commonly infest birds and are potential vectors of crimean-congo hemorrhagic fever (cchf) virus in west africa. an experimental model for investigating the role of birds in the cchf virus transmission cycle was developed. following cchf virus inoculation, antibodies were detected by enzyme-linked immunosorbent assay in one red-beaked hornbill and one glossy starling, but not in two laughing doves and six domestic chickens. none of the birds showed a detecta ... | 1994 | 8024058 |
| characterization and localization of d1 dopamine receptors in the sexually dimorphic vocal control nucleus, area x, and the basal ganglia of european starlings. | d1 dopamine receptors were pharmacologically characterized and localized by quantitative autoradiography in the basal ganglia of male and female european starlings (sturnus vulgaris). the d1 selective antagonist sch 23390 was used to label this receptor subtype. starlings are songbirds and possess a neural circuit implicated in the learning and production of song. this circuit includes a sexually dimorphic nucleus, area x, that is a subregion of the parolfactory lobe of the basal ganglia and is ... | 1994 | 8089655 |
| hair cell regeneration in the european starling (sturnus vulgaris): recovery of pure-tone detection thresholds. | behavioral detection thresholds were obtained from four starlings before, during, and after 11 days of subcutaneous injections of kanamycin. birds were operantly conditioned to respond to pure-tones ranging in frequency from 0.25 khz to 7 khz using the method of constant stimuli and were tested daily for 141 days after the first injection of aminoglycoside. all four birds sustained hearing losses greater than 60 db at frequencies from 4 khz to 7 khz by the end of the 11 day injection schedule. t ... | 1993 | 8113131 |
| length-dependent modulation of ang ii inotropism in rat myocardium: effects of myocardial infarction. | to determine whether changes in sarcomere length affect the inotropic response of the heart to angiotensin ii (ang ii) differently in dilated and failing myocardium, papillary muscles were removed 2 days after infarction, and the effects of ang ii were studied at various muscle lengths. myocardial infarction, which averaged 52% of the left ventricle inclusive of the interventricular septum, was characterized hemodynamically by left ventricular failure and right ventricular dysfunction. ang ii ad ... | 1994 | 8141379 |
| effect of changes in aortic pressure and in coronary arterial pressure on left ventricular geometry and function anrep vs. gardenhose effect. | sudden increases in aortic pressure (aop, mm hg) are associated with increases in left ventricular (lv) function which persist even after diastolic volume has returned to its initial value (anrep effect). likewise, increases in coronary arterial pressure (cap, mm hg) are associated with improved lv function (gardenhouse effect). in situ, increases in aop are paralleled by increases in both cap and coronary blood flow, i.e., oxygen supply. we investigated the individual contributions of aop and c ... | 1993 | 8147826 |
| 5'-nucleotidase inhibition enhances postischemic myocardial performance. | adenosine methylene diphosphate (ampcp), a 5'-nucleotidase inhibitor, was evaluated as an adjunct to cold crystalloid cardioplegic myocardial protection. cardiopulmonary bypass (cpb) was instituted at 28 degrees c in two groups of mongrel dogs (each, n = 6). myocardial ischemia was induced for 150 min by aortic cross clamping. crystalloid cardioplegia (4 degrees c) was infused into the aortic root at 15 ml/kg/20 min in the control group (cp). the experimental group (cp + ampcp) received identica ... | 1994 | 8152230 |
| the failing human heart is unable to use the frank-starling mechanism. | there is evidence that the failing human left ventricle in vivo subjected to additional preload is unable to use the frank-starling mechanism. the present study compared the force-tension relation in human nonfailing and terminally failing (heart transplants required because of dilated cardiomyopathy) myocardium. isometric force of contraction of electrically driven left ventricular papillary muscle strips was studied under various preload conditions (2 to 20 mn). to investigate the influence of ... | 1994 | 8156643 |
| [physiologic pacemaker therapy for drug-resistant heart failure in a patient with dilated cardiomyopathy and first-degree atrioventricular block: a case report]. | this is a report of a 65-year-old man with end-stage dilated cardiomyopathy, and first-degree atrioventricular (av) block, which had been resistant to intensive medical therapy and was eventually treated using a ddd pacemaker. the optimal av interval setting was determined using invasive right heart catheterization and doppler echocardiography. at a pacing rate of 92/min, an av interval setting between 200 and 100 msec increased left ventricular filling and enhanced myocardial contractility. an ... | 1993 | 8164130 |
| acquisition of photosensitivity in castrated male starlings (sturnus vulgaris) under short day photoperiods. | photorefractory castrated male starlings were transferred from a photoperiodic schedule of 18 h light:6 h dark to 1 h light:23 h dark, 5 h light:19 h dark, 8 h light: 16 h dark or 11 h light:13 h dark. plasma concentrations of lh were measured in blood samples taken at regular intervals, to give an indication of the reacquisition of photosensitivity under these schedules. concentration of plasma lh increased after 35, 38, 35 and 63 days, respectively; there was a steady increase in lh in all gro ... | 1994 | 8182615 |
| modeling the transient response to volume perturbations in the beating heart by the difference equation method. | discrete theoretical methods, compatible with the discrete features of the beating heart, are used together with experimental study to attain a quantitative understanding of the transient response to a volume perturbation and of sustained mechanical alternans (sma) in the beating heart. this is done in three stages. in stage a, a first-order difference equation describes the stroke volume (sv) response due to the frank-starling mechanism. it is shown that the value of gamma, the slope of the sv- ... | 1994 | 8184945 |
| three-dimensional transmural mechanical interaction between the coronary vasculature and passive myocardium in the dog. | the "garden hose" effect of coronary perfusion on diastolic left ventricular (lv) mechanics has been proposed to cause changes in systolic function by altering diastolic sarcomere length. we measured transmural distributions of three-dimensional shape change using radiopaque markers implanted in the lv free wall of eight isolated arrested canine hearts as functions of coronary arterial perfusion pressure (pp) and lv pressure (plv) and related these deformations to the local muscle fiber architec ... | 1994 | 8187283 |
| the relationship of intracranial venous pressure to hydrocephalus. | little is known about intracranial venous pressure in hydrocephalus. recently, we reported that naturally occurring hydrocephalus in beagle dogs was associated with an elevation in cortical venous pressure. we proposed that the normal pathway for cerebrospinal fluid (csf) absorption includes transcapillary or transvenular absorption of csf from the interstitial space and that the increase in cortical venous pressure is an initial event resulting in decreased absorption and subsequent hydrocephal ... | 1994 | 8194060 |
| left-to-right ventricular interaction with a noncontracting right ventricle. | left ventricular systole is known to contribute to generation of right ventricular pressure and stroke volume. to study the interactions in a dilated noncontractile right ventricle after cardiopulmonary bypass we created a variable volume, neo-right ventricle by excision and replacement of the right ventricular free wall with a xenograft pericardial patch. we investigated the interactions in eight dogs with neo-right ventricle, instrumented to measure cardiac pressures and cardiac output in cont ... | 1994 | 8196395 |
| extravascular protein in the renal medulla: analysis by two methods. | two methods have been used to test for the presence of extravascular protein in the interstitium of the renal inner medulla. first, ascending vasa recta (avr) segments were perfused with buffer containing 5 g/dl of albumin. the hydraulic pressure in the perfused vessel was varied to control transmembrane volume flux (jv) to the interstitium. interpolation to the point of zero jv was employed to estimate interstitial starling forces in the hydropenic rat papilla. analysis of those experiments pre ... | 1994 | 8203616 |
| effect of extravascular plasma protein on pressure-flow relations across synovium in anaesthetized rabbits. | 1. the effect of extravascular plasma protein on fluid flux through interstitial matrix was investigated in vivo by studying the pressure-flow relation across synovium during intra-articular infusions of protein solutions (usually bovine serum albumin). synovium is a sheet of non-epithelial cells separated by interstitium-filled gaps, beneath which are fenestrated capillaries: synovium regulates synovial fluid volume and composition. 2. albumin solutions (10-150 g l-1) of measured oncotic pressu ... | 1993 | 8229849 |
| exhaustion of frank-starling mechanism in conscious dogs with heart failure. | the goal of this study was to elucidate the ability of the left ventricle to accommodate an increase in preload (frank-starling mechanism) in the presence of congestive heart failure (chf) but in the absence of the complicating effects of hypertrophy and fibrosis. to accomplish this, the effects of volume loading were examined in eight conscious dogs during the control state and after 3 wk of right ventricular pacing (240 beats/min). chf increased heart rate (by 16 +/- 5 from 92 +/- 5 beats/min) ... | 1993 | 8238398 |
| [ventricular function in animals undergoing renal mass ablation. effect of blood pressure control]. | the causes of left ventricular hypertrophy (lvh) in chronic renal failure are multifactorial. the tail arterial pressure, heart weight, maximum developed pressure and pressure-volume relationship in animals with 5/6 nephrectomy (crf, n = 16) and crf animals who received furosemide by oral gavage (crf-f, n = 17) were studied. all crf animals increased their blood pressure (basal: 117.2 +/- 0.8; 6th week: 184.8 +/- 2.9, p < 0.001) but in those treated with furosemide the blood pressure stayed with ... | 1993 | 8242106 |
| thyroidectomy progressively renders the reproductive system of starlings (sturnus vulgaris) unresponsive to changes in daylength. | if starlings (sturnus vulgaris) are transferred to long days soon after being thyroidectomized, they show gonadal maturation but no subsequent photorefractoriness, suggesting a specific role for thyroid hormones in the development of photorefractoriness. this study tests an alternative hypothesis: that following thyroidectomy all gonadal responses to photoperiodic changes are progressively inhibited. photoperiodic responses of starlings were examined at two different times after thyroidectomy. t ... | 1993 | 8254293 |
| continuing development of the cleveland clinic-nimbus total artificial heart. | a completely implanted total artificial heart (tah) is under development by nimbus, inc., and the cleveland clinic foundation (ccf). key features of the system include an electrohydraulic energy converter, an automatic control system that produces a frank-starling response, and dual ventricles composed of graphite-epoxy and titanium with gelatin blood contacting surfaces. the system is controlled by a single substrate, hybridized microcircuit (the hybrid). fabrication of the tah control hybrid h ... | 1993 | 8268522 |
| an atrial hydraulic shunt in a total artificial heart. a balance mechanism for the bronchial shunt. | an implantable tah must be able to maintain physiologic atrial pressures over a range of left side shunt flows, which in humans can range up to 5% of the total cardiac output (co). the authors describe the characteristics of an atrial hydraulic shunt in an electrohydraulic tah. a small (10 cc stroke) chamber placed in line between the left atrial cuff and the inflow valve is shunted to the right hydraulic chamber. high left atrial pressure increases the volume displaced by this chamber; this con ... | 1993 | 8268531 |
| [cardiodynamics and cardiac pump function in hyperthermia]. | breaking of myocardial pumping function was shown in experiments in anesthesized dogs under hyperthermia. the end-systolic, end-diastolic and stroke volume was decreased under those conditions. the effectiveness of frank-starling mechanism was reduced in severe hyperthermia. | 1993 | 8274672 |
| a model of human microvascular exchange: parameter estimation based on normals and nephrotics. | a mathematical model is formulated and used to describe the distribution and transport of fluid and albumin in the human circulation, interstitium and lymphatics. two transcapillary mass exchange mechanisms are investigated: a homoporous 'coupled starling model', in which transcapillary albumin diffusion and convection occur within the same pathway, and a heteroporous 'plasma leak model', in which variations in structure and pressure are permitted along the length of the capillary. parameters us ... | 1993 | 8275681 |
| response of arterial resistance and critical pressure to changes in perfusion pressure in canine hindlimb. | the dynamic pressure-flow relationship in the canine hindlimb at normal arterial pressure is best explained by modeling a starling resistor (critical pressure, pcrit) at the level of the arterioles. regulation of flow can therefore occur at the starling resistor through changes in pcrit or along the length of the vessel through changes in arterial resistance (ra). we hypothesized that increasing perfusion pressure (pper) would increase pcrit due to the myogenic response but would decrease ra bec ... | 1993 | 8285232 |
| perceptual organization of auditory temporal patterns in european starlings (sturnus vulgaris). | the perception of continuously repeating auditory patterns by european starlings was explored in seven experiments. in experiment 1, 4 starlings learned to discriminate between two continuously repeating, eight-element, auditory patterns. each eight-element pattern was constructed from different temporal organizations of two elements differing in timbre. in experiments 2-7, the repeating patterns were transformed in ways designed to identify the starlings' perceptual organization of the patterns ... | 1993 | 8290326 |
| porphyrin profiles in the nestling european starling (sturnus vulgaris): a potential biomarker of field contaminant exposure. | porphyrin patterns in avian and mammalian tissues and/or excreta have been proposed as qualitative and quantitative biomarkers of exposure to polyhalogenated hydrocarbons, heavy metals, and other environmental contaminants. however, no widely distributed terrestrial species has been characterized as a suitable model in which to assess porphyrin profiles in the evaluation of environmental contaminant exposure. the european starling, whose nests can be readily established and manipulated on contam ... | 1993 | 8360942 |
| plasmalemmal vesicles represent the large pore system of continuous microvascular endothelium. | in the capillary physiology literature, molecules and particles larger than 10 nm are assumed to leave the plasma mostly through large pores located at the level of intercellular junctions in microvessels lined with a continuous endothelium. in morphological studies of similar microvessels, outgoing particles > 10 nm were detected in endothelial plasmalemmal vesicles not in intercellular junctions. because the probes may not be found in transit through the junctions because they may be swept awa ... | 1993 | 8368373 |
| circannual rhythms in starlings: response of castrated birds to 12-hr days depends on photoperiodic history. | the annual cycle of reproductive function in starlings (sturnus vulgaris) is driven by seasonal changes in daylength and consists of a 6-month period of photosensitivity, culminating in maximal gonadal development, followed by a 6-month period of photorefractoriness. if male starlings are held under a constant photoperiod of 12 hr of light per day (ld 12:12), some individuals show circannual rhythms of testicular size. do these rhythms consist of alternating periods of photosensitivity and photo ... | 1993 | 8369550 |
| auditory frequency generalization and a failure to find octave generalization in a songbird, the european starling (sturnus vulgaris). | many species of songbirds have absolute pitch perception. they memorize tones when discriminating between sequences and fail to generalize to novel frequency ranges. i examined frequency generalization in starlings (sturnus vulgaris) that were trained to discriminate between individual frequencies. starlings were tested for frequency generalization after training on 2- and 3-tone discriminations. there was no evidence for octave generalization, which is a hallmark of human absolute pitch percept ... | 1993 | 8370267 |
| a near perfect temperature adaptation of bilayer order in vertebrate brain membranes. | the bilayer order of a brain synaptic membrane fraction from a number of fish, mammalian and avian species have been compared in relation to their respective body temperatures using steady-state and time-resolved fluorescence anisotropy techniques. fluorescence anisotropy for both 1,6-diphenyl-1,3,5-hexatriene and trans-parinaric acid increased in the order: antarctic notothenia, trout, perch, cichlid, rat and starling, this also being the order of increasing body temperature. this suggests that ... | 1993 | 8373797 |