Search Results
Results 451 - 500 of 1161
< 5 6 7 8 9 10 11 12 13 14 15 >
Arabin B - - 1995
Radioimmunoassays of human placental lactogen and estriol levels in the maternal plasma, ultrasound biometry of the abdominal diameter (AD), pulsed Doppler measurements of uteroplacental arteries, the common carotid artery (CCA), and the umbilical artery (UA) and fetal heart rate monitoring were simultaneously performed in 219 risk pregnancies from 26 weeks' ...
Stípek S - - 1995
Oxygenation of both mother and child tissues oscillate frequently during labour. We tested the lipid peroxidation caused by reactive oxygen species which are produced in consequence of tissue reoxygenation and the inactivation of these species by the maternal and newborn superoxide dismutase. Total malondialdehyde in concentrations (mean +/- SE) of ...
Savich R D - - 1995
Fetal breathing movements are vital for normal fetal lung growth. Inhibition of these fetal breathing movements is associated with pulmonary hypoplasia. Pulmonary hypoplasia also occurs subsequent to alterations in other factors, such as a significant decrease in pulmonary blood flow. The prostaglandin system is known to have profound effects on ...
McDermott M - - 1995
The placenta receives two arterial blood supplies, i.e. one maternal and one fetal. It has been suggested that placental infarction should occur only if both blood supplies are compromised (Wigglesworth, 1984). This hypothesis has not been tested. Haemosiderosis of the trophoblast basement membrane (TBMH) has recently been identified as a ...
Forhead A J - - 1995
An AT1-specific angiotensin II receptor antagonist (GR117289; 1 mg/kg I.V. bolus) was administered daily to ten chronically catheterized, normotensive ewes during late pregnancy (from 126 +/- 1 days) until parturition (139 +/- 1 days); five control animals received an equivalent volume of vehicle solution. Following drug administration, mean maternal blood ...
Hooper S B - - 1995
Our aim was to compare the effects of short (4 h) and prolonged (24 h) periods of reduced uterine blood flow (RUBF) on fetal and placental uptake of O2, glucose, and lactate. In pregnant sheep, uterine and umbilical blood flows were measured under normal conditions and after 4 and 24 ...
Stevens A D - - 1995
To determine the effects on the fetus of high maternal levels of noradrenaline, experiments were carried out in 17 pregnant ewes (123-137 days gestation). Intravenous infusion of 40 mg/min of norepinephrine to the ewe for 1.5 h increased maternal arterial pressure and significantly decreased maternal placental blood flow (p < ...
Eckardt K U - - 1995
In has been long recognized that erythropoiesis in adults is under control of erythropoietin, a glycoprotein produced mainly by adult kidneys in inverse relation to oxygen availability. Increasing evidence indicates nowadays that EPO is also an essential growth factor for red cell precursors at different sites of fetal erythropoiesis. The ...
Eguchi K - - 1995
Erythrocyte deformability is an important determinant of microcirculation, of oxygen transport and release to the tissue. In an attempt to clarify the rheological peculiarity during pregnancy, erythrocyte deformability was measured in 10 nonpregnant controls and 10 pairs of mothers and newborns. When the hematocrit of the erythrocyte suspension in dextran ...
Jensen A - - 1995
The study concerned the role of the carotid sinus nerves in the effects of acute asphyxia on the fetal circulation. Fetal sheep (n = 12) were instrumented at approximately 130 days' gestation for placement of fetal vascular catheters and an occluder around the maternal descending aorta below the renal arteries. ...
Aldrich C J - - 1995
OBJECTIVE: To measure the effect of changes in maternal posture on fetal cerebral oxygenation during normal labour. DESIGN: A prospective study comparing changes in the fetal cerebral concentrations of oxyhaemoglobin, deoxyhaemoglobin and cerebral blood volume, measured by near infrared spectroscopy, in women with effective epidural analgesia when moved from the ...
Bissonnette J M - - 1995
The effect of the adenosine analogue R-N6-(phenylisopropyl)adenosine (R-PIA) on blood flow to the medulla and pons was examined in unanaesthetized fetal sheep. Microspheres labelled with isotopes were used to determine blood flow before and after instillation of 0.2 or 0.5 microgram R-PIA into the cerebrospinal fluid of the fourth ventricle. ...
Horibe S - - 1995
Nonimmune hydrops fetalis can be associated with many fetal conditions. A fetal blood sample obtained from ultrasound-guided cordocentesis can offer vital information about the underlying cause of the nonimmune hydrops fetalis, and perinatal management can be planned accordingly. We attempted to evaluate a case of nonimmune hydrops fetalis conveying poor ...
Llanos A J - - 1995
The fetal llama exposed to an intense degree of hypoxaemia did not increase cerebral blood flow, but showed a marked peripheral vasoconstriction. The same cardiovascular response is observed in fetal sheep submitted to a extremely severe hypoxaemia, when the initial compensatory vasodilatory mechanisms in brain and heart fail. To investigate ...
McLellan K C - - 1995
Experiments were conducted in eight pregnant sheep to determine the effect on fetal growth of mechanical restriction of uterine blood flow (RUBF) between 120 days and 134 days gestation. Uterine blood flow measured in the middle uterine arteries was 40% less in RUBF animals compared with control animals at the ...
Arbeille P - - 1995
The objective of the present study was to validate one or a combination of fetal Doppler parameters in order to assess acute fetal hypoxia in an ovine model. Acute hypoxia was induced by reducing umbilical, or maternal aortic flow (approx. 70%). A CW Doppler probe was fixed on the fetal ...
Eguchi K - - 1995
To elucidate the rheological difference in maternal and fetal blood by determining erythrocyte deformability, 20 pairs of mothers and newborns, and 20 nonpregnant women were studied. Erythrocyte deformability was measured by means of an electron spin resonance method. Erythrocyte deformability was dependent on the hematocrit, and there was an optimal ...
Szakmáry E - - 1995
Non-pregnant and pregnant CFY rats were given 3 mg/kg nickel chloride or physiological saline by gavage daily for eight days during days 7-14 of organogenesis. The haemodynamic investigations were carried out using 113Sn labelled microspheres. Nickel concentrations in maternal and fetal blood, as well as in amniotic fluid were determined ...
Parkinson S - - 1995
The purpose of this study was to determine the extent to which flow and velocity waveform indices are comparable as measured from the ovine fetal abdominal aorta and reflect downstream vascular resistance with changes in electrocortical activity. Nine chronically catheterized fetal sheep were studied near term with continuous measurement of ...
Welch C R - - 1995
OBJECTIVE: To investigate the effect of needle size and siliconization on fetal blood sampling, transfusion, and electrocardiography. METHODS: Standard needles were modified by increasing the internal (but not the external) diameter and either siliconization of the bore or external Teflon coating. The siliconized needles were subjected to a series of ...
Zucker R M - - 1995
We sought to determine whether flow cytometric analysis of circulating fetal blood cells could be used to rapidly detect perturbations of fetal erythropoiesis. In addition, we wanted to determine whether this approach would allow sample collection by exsanguination instead of fetal cardiac puncture, a difficult technique used to prevent contamination ...
Duggan P M - - 1995
The fetal sheep was used as a model to determine the extent of ultrasound-induced heating of brain tissue in procedures involving pulsed Doppler examination of fetal intracranial arteries. Temperature measurements were recorded in late-gestation fetuses insonated in utero. The centre frequency was 3.5 MHz and a pulse repetition rate of ...
Mitra S C - - 1994
OBJECTIVE: Our purpose was to study the short-term effect of maternal cocaine abuse on blood flow of the fetal kidney and the fetal hourly urine output. STUDY DESIGN: Thirty-three pregnant patients of various gestational ages with a history of cocaine abuse were studied. Patients were included if the urine specimen ...
Battaglia C - - 1994
The aim of this study was to determine the efficacy of long-term maternal hyperoxygenation in comparison with bed rest in the management of mildly growth-retarded fetuses (5-10th centile).Thirty-eight patients with intrauterine growth retardation were studied. The patients were divided into oxygen-treated (n = 18) and untreated (n = 20) groups. ...
Iida H - - 1994
Maternal cocaine injection causes fetal hypoxemia, hypertension, and increased cerebral blood flow (CBF) in sheep. To test the hypothesis that increased fetal CBF is not due solely to fetal hypoxemia, we injected cocaine directly into a fetal vein. A single dose of cocaine [1 (group 1; n = 7) or ...
Boura A L - - 1994
1. Humans have a haemochorial, villous placenta. Uterine blood passes through maternal sinuses, bathing placental villi through which fetal blood circulates. Blood flow through each circulation is high and vascular resistance low. This haemodynamic situation is essential for efficient placental function. 2. The low placental vascular resistance is due to ...
Kaeda J S - - 1994
Fetal blood normally has a higher oxygen affinity than maternal blood because of the predominance of haemoglobin (Hb) F in the former and of Hb A in the latter; this predominance facilitates the transfer of oxygen from maternal to fetal blood. We report two patients who had exclusively or predominantly ...
van den Berg P P - - 1994
BACKGROUND: In cases of fetal congenital heart block, the fetal heart rate (FHR) pattern is uninterpretable, often leading to an operative delivery. Reflectance pulse oximetry, a new technique that continuously measures the fetal arterial oxygen saturation (SaO2) during labor, is potentially useful in intrapartum monitoring of fetuses with this condition. ...
Hedriana H L - - 1994
OBJECTIVE: Our purpose was to define the accuracy of currently available methods of ultrasonographically estimating human fetal urinary flow rate in a controlled setting. STUDY DESIGN: Eleven fetal cadavers were studied in a water bath. Saline solution was incrementally infused into the bladder to simulate a rate of 1 ml/min. ...
Noordam M J - - 1994
In 14 normally developing term fetuses, the relationship between the blood flow velocity waveforms at cerebral arterial level (internal carotid artery, anterior, middle and posterior cerebral artery) and fetal behavioural states was studied using Doppler colour flow imaging. Behavioural state dependent changes in absolute flow velocities occurred in all vessels, ...
Ryan G - - 1994
The concept of transfusing the fetus in utero is simple, but its success demands an experienced, dedicated team, with excellent laboratory back-up. High-resolution ultrasound has enabled us to sample fetal blood. This allows immediate, precise assessment and rational treatment of the anemic fetus, with improved outcome for all such fetuses ...
Georgiou I - - 1994
A method for rapid estimation of fetal blood content during cordocentesis is described. This procedure gives an opportunity to determine the contamination of the fetal sample by maternal blood as soon as possible. The method is based on the ability of fetal hemoglobin to resist denaturation in alkaline conditions, and ...
Oepkes D - - 1994
OBJECTIVE: To assess the value of ultrasonography and Doppler to predict the severity of fetal haemolytic anaemia. DESIGN: Ultrasonographic measurements of the fetal liver, spleen, umbilical vein and placenta, and Doppler measurements of umbilical venous and fetal aorta flow velocities were performed before the first intrauterine blood transfusion. Multivariate regression ...
Newnham J P - - 1994
OBJECTIVE: The purpose of this study was to investigate the fetal catecholamine and arterial blood gas responses to ultrasonographically guided percutaneous needle aspiration of blood from a fetal cardiac ventricle. STUDY DESIGN: A crossover trial design was used. Nine pregnant sheep of 120 to 130 days' gestation were stratified to ...
Faris F - - 1994
A relatively new optical method based on near infra-red spectroscopy was evaluated in preliminary clinical trials for noninvasive intrapartum fetal monitoring. The measurements were performed using mainly the light reflection mode of monitoring. Continuous monitoring of changes in the concentrations of oxygenated and deoxygenated haemoglobin and thus changes in total ...
Fridén B E - - 1994
OBJECTIVE: The objective of this study was to quantitatively determine an immunoglobulin G receptor, placental alkaline phosphatase, and its ligand immunoglobulin G in maternal and fetal blood and to study the transport capacity of the receptor. STUDY DESIGN: Venous blood samples from 66 term pregnant women and cord samples from ...
Covert R F - - 1994
We studied hemodynamic responses to cocaine and two metabolites, cocaethylene (CE) and benzoylecgonine (BE), in five conscious ewes and fetuses, which were chronically instrumented to measure maternal and fetal aortic pressures, uterine artery blood flow (Qutr) and fetal common carotid artery blood flow (Qcar) to estimate cerebral blood flow. Conscious ...
Rhyan J C - - 1994
A near-term aborted bison (Bison bison) fetus was collected near Old Faithful geyser in Yellowstone National Park, Wyoming (USA). On necropsy, the fetus liver had a small capsular tear, and there was a small quantity of blood in the peritoneal cavity. Microscopic lesions included mild, purulent bronchopneumonia and mild, multifocal, ...
Wladimiroff J W - - 1994
Behavioural state dependent changes occur in the circulation of the normally developing human fetus at term. During fetal behavioural state 2F (active sleep), there seems to be preferential blood flow through the ductus venosus and foramen ovale into the left heart. Increased left ventricular output of well-oxygenated blood during fetal ...
Berger P J - - 1994
We measured blood flow to the respiratory muscles of the fetal lamb using the radioactively-labelled microsphere technique in order to assess whether fetal breathing is an energetically costly activity as has been reported. Diaphragm flow ranged from 6.4-35.2 ml.min-1.100 g-1 during fetal apnoea and rose to 21.1-615 ml.min-1.100 g-1 during ...
Aldrich C J - - 1994
OBJECTIVE: To test the hypothesis that intrapartum maternal oxygen administration increases fetal cerebral oxygenation during normal labour. DESIGN: A prospective study comparing changes in fetal cerebral concentrations of oxyhaemoglobin, deoxyhaemoglobin and cerebral blood volume measured by near infrared spectroscopy, before, during and after maternal oxygen administration using a 60% Ventimask. ...
Huang S C - - 1994
Whether preeclampsia affects the fetal hematologic system still remains a controversial issue. The purpose of this series was to examine the hypothesis that preeclampsia may or may not cause adverse effects on fetal hemogram, including erythrocytes, leukocytes, and platelets. In addition, no one, to date, has reported the effect on ...
Hadi H A - - 1994
Perinatal brain damage and compromised long-term neurologic outcome have been a topic of major concern and continuing debate. Until recently the occurrence of fetal brain injury was attributed to intrapartum events. However, evidence continues to accumulate that neurologic damage can occur during fetal life unrelated to intrapartum events. We report ...
Schröder H J - - 1994
The effect of reduced umbilical blood flow rate on fetal core temperature was investigated in five chronically instrumented fetal sheep (gestational age 124 days). On average, fetal-maternal temperature difference increased 0.13 +/- 0.02 degrees C when blood flow rate was decreased to about 1/3 of normal (248 +/- 69 ml ...
Cock M L - - 1994
OBJECTIVE: Our aim was to determine the effects of a sustained reduction in uteroplacental perfusion, leading to fetal hypoxia, on determinants of amniotic fluid volume in sheep. STUDY DESIGN: Surgery was performed on five pregnant ewes 110 to 116 days after mating. At 127.3 +/- 2.2 days uterine blood flow ...
Bocking A D - - 1994
In the mature ovine fetus, ethanol decreases fetal breathing movements (FBM), which is temporally related to increased prostaglandin E2 (PGE2) concentration, decreases blood glucose concentration, increases blood lactate concentration, and decreases uterine electromyographic (EMG) activity. The objective of this study was to determine the effects of ethanol on these variables ...
Barzago M M - - 1994
Mefloquine (MQ) is highly effective in the treatment and prophylaxis of chloroquine-resistant Plasmodium falciparum malaria. Despite its widespread use, scant information is available on the transplacental profile and time course of MQ transfer across the human placenta. Six human placentas were perfused with human plasma for 180 min using recirculating ...
Brace R A - - 1994
The aim of this study was to determine the effects of 24 h of hypoxia on fetal swallowing and urine flow rates. The study design included successive 24-h control, hypoxia, and recovery periods. To induce hypoxia, we infused nitrogen into the trachea of late-gestation pregnant sheep. During hypoxia, there were ...
Helou S - - 1994
There are scant data regarding the development of cerebrovascular autoregulation in fetuses. We tested the hypothesis that a decrease in cerebrovascular resistance (CVR) at reduced cerebral perfusion pressure (CPP) is absent in midgestation and near-term fetal sheep. Catheters were chronically implanted for microsphere determination of cerebral blood flow (CBF) in ...
Welch R - - 1994
OBJECTIVE: Our aim was to determine the changes in fetal hemorheologic parameters caused by fetal intravascular transfusion for alloimmune anemia. STUDY DESIGN: Fetal blood samples were collected before and after 95 fetal transfusions in 31 women. Fetal hematocrit, whole-blood viscosity at a variety of shear rates, plasma viscosity, fetal fibrinogen, ...
< 5 6 7 8 9 10 11 12 13 14 15 >