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López Ramón y Cajal C - - 1996
Here presented are the different human fetal larynx functions. Analysis and observation of the organ show at least three behavioural patterns: swallowing, respiratory and phonetic. The respiratory function coincides with a blood aspiration through the venosus duct (phenomenon measured by pulsed Doppler) which increases the amount of oxygenated blood in ...
Okamura K - - 1996
This study was designed to show how accurately the pulsed Doppler fetal blood flow velocimetry reflects fetal blood gas values. Abnormal Doppler umbilical artery (UA) velocimetry was defined when the value deviated from the 95% confidence interval of the normal fetuses. Fetal acidemia, hypoxemia, or hypercapnia was defined when the ...
Irion O - - 1996
OBJECTIVES: To determine the association between fetal heart rate accelerations, whether spontaneous or induced by vibratory acoustic stimulation, and subsequent scalp pH values in presence of a suspicious intrapartum fetal heart rate tracing, and thereby assess the ability of accelerations to predict a concurrent normal fetal scalp blood pH. DESIGN: ...
Carpani G - - 1996
In order to evaluate fetal erythropoiesis we measured red blood cells, hemoglobin, hematocrit, serum transferrin receptor (sTfR), and iron status parameters in fetuses undergoing percutaneous umbilical blood sampling, and in normal newborns at term. We found high levels of sTfR in fetuses and newborns as compared with normal adults (3,149 ...
Sakamoto H - - 1996
This study was designed to compare the effects of nicardipine (0.02 mg/kg) and labetalol (0.5 mg/kg) on the uterine blood flow and fetal circulation after intravenous administration in unanesthetized, chronically instrumented pregnant goats. Significant decreases in maternal blood pressure and uterine blood flow were observed in both groups. The maternal ...
PityƄski K - - 1996
The vascular architecture of adrenal glands was investigated in human fetuses aged from 16 to 24 weeks, using microcorrosion casts and scanning electron microscopy. The fetal adrenals showed an arrangement of blood vessels remarkably similar to that described in adult glands. There was a clear centripetal pattern from superficial arteries ...
Sepulveda W - - 1996
Serial Doppler ultrasonography in a severely growth-restricted fetus revealed progressive reduction in pulsatility index of the middle cerebral artery, consistent with brain-sparing effect. At 29 weeks, 1 week before fetal death, the pulsatility index in the middle cerebral artery returned to normal values and became reversed the day before fetal ...
Sekizawa A - - 1996
We developed a method that allows prenatal diagnosis of Duchenne muscular dystrophy using a single nucleated erythrocyte (NRBC) isolated from maternal blood. Maternal blood was obtained at 8 to 20 weeks of gestation. NRBCs were separated with Percoll using a discontinuous density gradient method and then collected by micromanipulator under ...
Reynolds J D - - 1996
Fetal hypoxia is a hypothesized mechanism of ethanol teratogenesis. The objective of this study was to test this hypothesis by determining the effects of maternal ethanol infusion on uterine blood flow (UBF) and fetal oxygen status. UBF was measured with an electromagnetic flow probe placed around the left maternal uterine ...
Graham C H - - 1996
Atrial natriuretic peptide (ANP) is a vasoactive molecule with a potential role in modulating uteroplacental blood flow. We examined the expression of ANP in the third-trimester fetomaternal interface by immunohistochemistry performed on sections of placental tissue as well as by reverse transcriptase-polymerase chain reaction (RT-PCR) and RIA performed on isolated, ...
Aliakbar S - - 1996
OBJECTIVE: The aim of the present study was to determine the erythrocyte CAI and CAII concentrations in fetal blood over a wide gestational range, and compare levels to those found in neonates and adults. METHODS: Human erythrocyte CAI and CAII concentrations were measured in fetal (n=38), neonatal (n=10) and adult ...
Sekizawa A - - 1996
OBJECTIVE: To develop a method that allows prenatal diagnosis of the fetal RhD blood type from maternal blood. METHODS: Maternal blood was obtained at 8-31 weeks' gestation, and nucleated erythrocytes were separated with Percoll using a discontinuous density gradient method, then collected individually by micromanipulation under microscopic observation. After whole ...
Chao C R - - 1996
Cocaine administration during pregnancy results in major maternal cardiovascular effects that in some cases exceed those observed in the nonpregnant state. Animal studies have shown increases in heart rate and blood pressure and decreases in regional organ blood flow. Fetal effects include arterial hypoxemia, increases in blood pressure and heart ...
Altshuler G - - 1996
This article on the placenta includes considerations of chorioamnionitis, villitis, preeclampsia, and other low placental blood flow states and aspects of the circulating lupus anticoagulant syndrome. The author explains that, although gross and microscopic placental findings document placental features at one point in time, they also reflect ongoing pathophysiologic changes. ...
Peña A E - - 1996
OBJECTIVES: Cocaine administration to near-term pregnant sheep causes fetal hypoxemia, but oxygen delivery to the heart and brain are preserved because of increased blood flow. We hypothesized that cocaine administration during earlier fetal gestation impairs oxygen delivery to the heart and brain. STUDY DESIGN: Ten pregnant ewes and fetuses at ...
Carter A M - - 1996
To ascertain whether repeated hypoxic stress would alter the response of the adrenal cortex to adrenocorticotropic hormone (ACTH), by premature activation of the hypothalamic-pituitary-adrenal axis, we studied fetal sheep subjected to daily reduction of arterial oxygen content by embolization of the fetal placental circulation with 15 microns microspheres for 8 ...
Stevenson K M - - 1996
1. The angiotensin type 1 (AT1) receptor antagonist, losartan (10 mg/kg) was infused intravenously into nine chronically catheterized fetal sheep (125-132 days gestation). Losartan reduced the fetal systolic (P <0.01) and diastolic (P <0.01) pressor response to 5 microg angiotensin II (AngII) i.v. from 27.4 +/- 1.5 to 7.4+/-0.9 and ...
Weiner C P - - 1996
OBJECTIVE: Lower changes in optical density (450 nm) measurements have been reported in fetuses with anti-Kell anemia compared with those anti-D anemia. The purpose of this investigation was to determine if hemolysis and erythropoiesis differ between anti-Kell and anti-D hemolytic disease. STUDY DESIGN: Ninety-three pregnancies complicated by either anti-D or ...
McNutt T L - - 1996
Viable, intact rabbit sperm, prepared, processed, and flow cytometrically sorted, were used in this study to determine the influence of flow sorting on fertilization and embryo development. In experiment I, flow-sorted or control (unstained and unsorted) sperm were surgically inseminated into the uterine horn of hormonally primed does (10 to ...
Covert R F - - 1996
To determine whether common carotid artery blood flow measured with an ultrasonic flow transducer would predict brain blood flow in fetal sheep, we measured unilateral common carotid artery blood flow and compared this to simultaneous measurements of total brain blood flows made by radioisotope-labelled microsphere techniques. We studied anaesthetized, exteriorized ...
Burchfield D J - - 1996
Eight time-dated pregnant ewes at 125 days' gestation (145 days = term) underwent surgery for placement of fetal vascular catheters, electrodes for recording fetal behavioural state, and maternal venous catheters. Three days later, fetal cerebral and myocardial blood flow were determined by the coloured microsphere technique under four conditions: (1) ...
Wallace M J - - 1996
Previous studies have shown that moderate fetal asphyxia reduces the secretion rate of fetal lung liquid. The present aim was to determine the relative effects of the individual components of asphyxia (hypoxia, hypercapnia and acidaemia) on lung liquid secretion in fetal sheep. Fetal hyperoxia was also studied to determine the ...
Yang J - - 1996
Two pairs of primers were designed based on the sequence of bovine Sry and applied to the assay of Sry sequence from maternal blood using the polymerase chain reaction. Of the total twenty DNA samples from peripheral blood of late pregnant cow, nine appeared positive with male-specific Sry sequence. The ...
Boyle D W - - 1996
The purpose of the present investigation was to study the effect of 7 days of uterine blood flow reduction on fetal growth. Reduction in uterine blood flow was accomplished by external occlusion of the terminal aorta in 20 pregnant sheep. Linear growth was monitored daily by means of a crown-rump ...
Berger R - - 1996
Asphyxia is one of the major causes for fetal brain damage. Although the quality of life of the so affected children is mostly very limited, the pathogenesis of hypoxic fetal brain damage is poorly understood. Particularly, there is a lack of studies, in which cerebral oxygen delivery is directly correlated ...
Cock M L - - 1996
1. Our aim was to identify mechanisms whereby prolonged fetal hypoxaemia alters renal function and urine production in fetal sheep. 2. Fetal hypoxaemia was induced for 24 h by reducing uterine blood flow at 129.0 +/- 2.1 days of gestation (term 145-147 days), causing a reduction in fetal arterial O2 ...
Brossard Y - - 1996
PURPOSE: To determine the frequency of maternal-fetal hemorrhage at or above 1 microliter of maternal whole blood. METHODS: Seventy-three mothers whose red blood cells bore an Rh antigen (Rh D, Rh c, Rh E) that was absent on red blood cells of their newborns were identified and a new cytological ...
Saling E - - 1996
Modern intensive monitoring of the fetus during labor affords the opportunity for the greatest possible safety to the infant, whilst at the same time dispensing with unnecessary operations to terminate labor which can be dangerous for the mother and her child. Developments over the past 28 years, since cardiotocography has ...
Gleason C A - - 1995
Previous studies in near-term sheep have shown that maternal cocaine injection causes acute fetal cerebral vasodilation along with transient hypoxemia and hypertension. Preterm sheep fetuses have lower cerebral O2 consumption (CMRO2) and their cerebrovascular responses to hypoxemia are attenuated compared with near-term fetuses. We therefore tested the hypothesis that fetal ...
Stek A M - - 1995
OBJECTIVES: The current study was designed to test the hypothesis that maternally administered methamphetamine decreases fetal PaO2 by reducing uterine blood flow and to determine the cardiovascular and blood gas responses to varying doses of methamphetamine given both to the fetus and the mother. STUDY DESIGN: Nine near-term pregnant sheep ...
Kwan E - - 1995
The effects of 15-50% fetal hemorrhage (at approximately 1%/min) were studied in 13 pregnant ewes at 130-135 days of gestation for up to 5 days posthemorrhage. The upper limit of acute blood loss appears to be approximately 45%, and the rate of restoration of blood volume decreases with the severity ...
Carter A M - - 1995
OBJECTIVE: To determine whether arginine vasopressin (AVP) at plasma concentrations measured during moderate hypoxemia affects adrenal blood flow. STUDY DESIGN: Regional blood flows were measured in 5 unanesthetized normoxemic fetuses (124-128 days' gestation) during a 24-h intravenous infusion of AVP in isotonic saline solution. Another 5 fetuses received an infusion ...
Kwan E - - 1995
The metabolic and behavioral effects of 40-45% hemorrhage (at approximately 1%/min) were studied in nine fetal lambs in utero (130-135 days of gestation) until 2 days posthemorrhage. Umbilical blood flow (Qum) fell from 192 +/- 14 to 100 +/- 9 ml.min-1.kg-1 at the end of blood loss, and on the ...
Johnson N - - 1995
OBJECTIVE: To determine whether pulse oximetry has the potential to replace scalp blood pH sampling in infants with abnormal cardiotocographs. STUDY DESIGN: The average scalp oximetry reading in labor recorded with an experimental N400 system was compared with fetal scalp blood pH. RESULTS: The average oximetry readings were unrelated to ...
Brace R A - - 1995
Blood volume returns toward normal after hemorrhage much more rapidly in the fetus than in the adult due to a rapid entry of fluid and plasma proteins into the fetal circulation. One potential source of fetal fluids and plasma proteins is the lymphatic system, since basal lymph flow rate and ...
Père M C - - 1995
To study nutrition and metabolism in the fetal pig, a chronic catheterization method was developed that allows blood sampling in arteries and veins, at both the umbilical and uterine sources, in the conscious, unstressed animal. A catheter was inserted in the fetal aorta through a femoral artery, and another one ...
Woudstra B R - - 1995
In fetal sheep, arterial blood gas values show considerable spontaneous fluctuations. The aim of the present study was to obtain quantitative data on fetal blood gas variability. Accurate assessment of the intraindividual variations can hardly be obtained from intermittent blood samples, but requires continuous measurement. For this purpose we developed ...
Carter A M - - 1995
To examine the role of endogenous adrenocorticotropic hormone (ACTH) in adrenal blood flow responses to hypoxia, we studied unanesthetized ovine fetuses during an intravenous infusion of cortisol or vehicle. Fetal hypoxia was induced after 5 h of cortisol or vehicle infusion. Control fetuses were not made hypoxic. Blood flows were ...
Bassily M - - 1995
There is little information on the effects of maternal and fetal placental blood flow rates, which can change independently, on the placental transfer rate of drugs of different placental permeabilities. We examined the effects of varying maternal and fetal perfusion flow rates on the placental transfer of three model compounds; ...
Carroll S G - - 1995
The value of fetal haematological indices in the prediction of intra-uterine infection in 91 cases of preterm prelabour amniorrhexis was examined. Cordocentesis and amniocentesis were performed for the diagnosis of intra-uterine infection. The patients were subsequently divided into three groups, depending on the results of fetal blood and amniotic fluid ...
Moise K J KJ - - 1995
OBJECTIVE: The addition of ultrasonography and ultrasonographically directed fetal blood sampling was attempted in an effort to study the fetal effects of red blood cell alloimmunization in a rabbit model. STUDY DESIGN: Nineteen New Zealand does were alloimmunized to incompatible red blood cells. Sensitized does were bred twice, once with ...
Faber J J - - 1995
1. Maternal blood was made transiently hypertonic by rapid I.V. infusion of a concentrated mannitol solution into pregnant ewes bearing lambs with an indwelling flow sensor and vascular catheters. 2. The transplacental flows of water and of Na+ and Cl- were calculated from the umbilical arteriovenous differences in the concentrations ...
Stevenson K M - - 1995
1. Angiotensin II (AII) was infused I.V. into seven chronically catheterized fetal sheep (gestational age, 120-136 days). The effects of short-term infusions of 6 and 12 micrograms kg-1 h-1 for 1.5 h were compared with the effects of infusing 6 micrograms kg-1 h-1 for 3 or 5 days (long-term infusion). ...
Yang J M - - 1995
BACKGROUND: Hypoxic complications are thought to be the result of vascular lesions in the maternal-placental or fetal-placental circulation, with a resultant decrease in blood flow. This study was designed 1) to explore what kind of pathophysiological changes occur in the maternal-placental-fetal circulations associated with acute fetal distress, and 2) to ...
Simpson J L - - 1995
Fetal cells exist in maternal blood and can be utilized for prenatal genetic diagnosis. The use of polymerase chain reaction (PCR) technology on maternal blood has enabled the detection of fetal sex, Mendelian disorders (e.g. beta-globin mutations), HLA polymorphisms and fetal Rhesus (D) blood type. Enrichment for erythroblasts and trophoblasts ...
Alahuhta S - - 1995
BACKGROUND: Ropivacaine is a new long-acting amide local anesthetic that has been shown in animal studies to have less dysrhythmogenic and cardiotoxic potential than bupivacaine. The intravenous administration of ropivacaine has not been associated with any detrimental effects on uterine blood flow in pregnant ewes. The purpose of this randomized, ...
Aldrich C J - - 1995
OBJECTIVE: To measure the effect of maternal pushing during the second stage of labour on fetal cerebral oxygenation and blood volume. DESIGN: A prospective study comparing changes in the fetal cerebral concentrations of oxyhaemoglobin, deoxyhaemoglobin and cerebral blood volume, before and during maternal pushing in the second stage of labour. ...
Ross M G - - 1995
In the near-term ovine fetus, systemic hyperosmolality stimulates dipsogenic responses. Putative systemic dipsogens (hypertonicity, angiotensin II) may initiate responses by stimulation of select cerebral circumventricular nuclei lacking a blood-brain barrier. To investigate whether central osmotic-dipsogenic mechanisms are functional in utero, fetal swallowing responses to intracerebroventricular (i.c.v.) hypertonic saline were examined. ...
Barnard J M - - 1995
OBJECTIVE: To determine the effects of maternal abdominal carbon dioxide (CO2) insufflation on placental blood flow and fetal blood gas measurements in the pregnant ewe. METHOD: Five time-bred ewes at 110 days' gestation were surgically prepared with maternal and fetal catheters placed for subsequent measurement of vascular pressures, blood gas ...
Marcus M A - - 1995
Administration of fluids intravenously prior to spinal and epidural analgesia in obstetrics is required to prevent maternal hypotension and fetal hypoxia. A colloid solution, such as hydroxyethyl starch (HES), might be preferable considering the capacity to stay intravascularly for a longer period. In this study the placental transfer of HES ...
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