Abstract:
:In artificial tubes as well as in blood vessels with diameters less than 500 microns, blood viscosity decreases with decreasing diameter (Fahraeus-Lindqvist effect). Our study measured viscosity of red blood cells (RBC) from 10 preterm infants, 10 term neonates, and 10 adults by means of a capillary viscometer. RBC were suspended in buffer at hematocrits of 0.20, 0.40, and 0.60 1/1 (1.00 1/1 = 100%). Tubes with diameters of 50, 100, and 500 microns were perfused with these suspensions. Viscosity in the 500-microns tubes was not significantly different, at any hematocrit, among the three groups. Viscosity decreased at each of the adjusted hematocrits in the three groups when going from a 500-microns tube to a 50-microns tube. At a hematocrit of 0.60 1/1, viscosity reduction averaged 48 +/- 7% in the preterm infants, 42 +/- 8% in the full-term neonates, and 35 +/- 5% in the adults, whereas the reductions at a hematocrit of 0.20 1/1 were only 32 +/- 6, 27 +/- 4, and 24 +/- 6%, respectively. For the combined data from the neonates and adults, there was a significant inverse relationship of the viscosity in 50-microns tubes at a hematocrit of 0.60 1/1 to the mean corpuscular volume (r = 0.69). To evaluate whether increased membrane elasticity of neonatal RBC contributes to the stronger viscosity reduction of neonatal RBC in narrow tubes, heated neonatal and adult RBC were also studied. The resulting loss of membrane elasticity caused a marked decrease in the viscosity reduction in 50-microns tubes, particularly in the neonates.(ABSTRACT TRUNCATED AT 250 WORDS)
journal_name
Pediatr Resjournal_title
Pediatric researchauthors
Zilow EP,Linderkamp Odoi
10.1203/00006450-198906000-00009subject
Has Abstractpub_date
1989-06-01 00:00:00pages
595-9issue
6eissn
0031-3998issn
1530-0447journal_volume
25pub_type
杂志文章abstract::Spleens from 1-20-wk-old guinea pigs infected in utero with Treponema pallidum and age-matched controls, born to normal and heat-killed (56 degrees C, 2 h.) T. pallidum-injected mothers, were examined for their in vitro lymphoproliferative response to phytohemagglutinin, concanavalin A, and lipopolysaccharide. Additio...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-199712000-00013
更新日期:1997-12-01 00:00:00
abstract::Hydrocephalus may result in loss of tissue associated with neuronal degeneration, axonal damage, and reactive gliosis. The soluble form of the anti-apoptotic regulator Fas (sFas) and the pro-apoptotic factors soluble FasL (sFasL) and activated caspase 3 were studied in the cerebrospinal fluid of infants with hydroceph...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/01.PDR.0000084114.83724.65
更新日期:2003-11-01 00:00:00
abstract::Naloxone, a specific opiate antagonist with no agonist properties, in doses of 0.4 and 4.0 mg/kg was found to markedly reduce the duration of primary apnea in asphyxiated newborn rabbits. There was no effect on the duration of the hyperpneic phase (time to primary apnea) or on survival time (time to last gasp). It is ...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-198004000-00021
更新日期:1980-04-01 00:00:00
abstract::This study determines the inotropic effects of prostaglandin D2 (PGD2) and prostaglandin E1 (PGE1) in the isolated, arterial perfused newborn (NB) and adult (A) rabbit heart. Significant positive inotropism of PGD2 was observed at all concentrations studied (1 X 10(-17) to 1 X 10(-7) M) in the two age groups; the effe...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-198412000-00010
更新日期:1984-12-01 00:00:00
abstract::Mesenchymal stem cell (MSC) transplantation represents the next breakthrough in the treatment of currently intractable and devastating neonatal disorders with complex multifactorial etiologies, including bronchopulmonary dysplasia, hypoxic ischemic encephalopathy, and intraventricular hemorrhage. Absent engraftment an...
journal_title:Pediatric research
pub_type: 杂志文章,评审
doi:10.1038/pr.2017.249
更新日期:2018-01-01 00:00:00
abstract::The effect of ingestion of uncooked cornstarch (2 g/kg body weight) in water, uncooked starch (1 g/kg) added to a meal, and glucose (2 g/kg) in water, was studied in eight patients with type IA glycogen storage disease (GSD) and one patient with type IB GSD. Blood glucose concentrations were determined at 30-min inter...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-198409000-00015
更新日期:1984-09-01 00:00:00
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journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-200102000-00008
更新日期:2001-02-01 00:00:00
abstract::In its normal circulatory environment, the fetal left ventricle can maximally increase output less than 2-fold, in contrast to the nearly 3-fold increase that occurs at birth. Several studies have attributed this finding to fetal myocardial "immaturity," and speculated that there is a rapid maturation of the myocardiu...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-199105010-00011
更新日期:1991-05-01 00:00:00
abstract::The risk of pulmonary hemorrhage is increased in extremely low birth weight infants treated with surfactant. The pathogenesis of this increased risk is far from clear. We tested whether exposure of cell membranes to surfactant may lead to increased membrane permeability, hypothesizing that this process may contribute ...
journal_title:Pediatric research
pub_type: 杂志文章
doi:
更新日期:1995-01-01 00:00:00
abstract::The use of tissue engineering to develop new urinary bladder could have direct impact on children suffering from congenital bladder dysfunction. Current bladder tissue engineering protocols rely on scaffolds to support the ingrowth of new cells and the subsequent development of new tissues. The interaction between cel...
journal_title:Pediatric research
pub_type: 杂志文章,评审
doi:10.1203/PDR.0b013e3181d35034
更新日期:2010-05-01 00:00:00
abstract::Monocyte chemoattractant protein-1 (MCP-1), acting through its C-C chemokine receptor 2 (CCR-2), has important roles in inflammation, angiogenesis, and wound repair. The individual and combined effects of inhaled nitric oxide (NO) and hyperoxia on lung MCP-1 and CCR-2 in relation to lung leukocyte dynamics are unknown...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-200111000-00017
更新日期:2001-11-01 00:00:00
abstract::Many trials of mesenchymal stem cells (MSCs) have been published in the past 5-6 y. MSCs inhibit T-cell alloreactivity in vitro by soluble factors and direct cell-to-cell contact. They are safe to infuse in humans with no acute toxicity and no ectopic tissue formation. Promising results of MSC infusion for graft-vs.-h...
journal_title:Pediatric research
pub_type: 杂志文章,评审
doi:10.1038/pr.2011.56
更新日期:2012-04-01 00:00:00
abstract:BACKGROUND:Angiotensin (ANG) II is involved in experimental hyperoxia-induced lung fibrosis. Angiotensin-converting enzyme-2 (ACE-2) degrades ANG II and is thus protective, but is downregulated in adult human and experimental lung fibrosis. Hyperoxia is a known cause of chronic fibrotic lung disease in neonates, but th...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1038/pr.2015.27
更新日期:2015-05-01 00:00:00
abstract::Oxidant stress has been implicated as playing a role in the pathogenesis of cholestatic liver injury. The objective of this study was to determine whether the xanthine oxidase/xanthine dehydrogenase enzyme system was involved in this oxidant stress. Adult Sprague-Dawley rats were treated with the xanthine oxidase inhi...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-199809000-00022
更新日期:1998-09-01 00:00:00
abstract::To clarify the prevalence of Japanese children thought to be at a risk for infection with GB virus-C (GBV-C)/hepatitis G virus (HGV), we investigated the detection rates of serum GBV-C/ HGV ribonucleic acid (RNA) by reverse transcription-seminested PCR and serum anti-HGV-E2 antibody by ELISA in 162 children with histo...
journal_title:Pediatric research
pub_type: 临床试验,杂志文章
doi:10.1203/00006450-199901000-00021
更新日期:1999-01-01 00:00:00
abstract::Growth hormone (GH) regulates growth and development in the postnatal period but lacks somatotropic activity in the fetus. In contrast, the placental hormone placental lactogen (PL) stimulates amino acid transport, DNA synthesis, and somatomedin production in isolated fetal tissues, suggesting that PL may function as ...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-199208000-00015
更新日期:1992-08-01 00:00:00
abstract:BACKGROUND:The aim of this study was to determine whether small-for-gestational-age (SGA) infants born very prematurely had increased respiratory morbidity in the neonatal period and at follow-up. METHODS:Data were examined from infants recruited into the United Kingdom Oscillation Study (UKOS). Of the 797 infants who...
journal_title:Pediatric research
pub_type: 杂志文章,多中心研究,随机对照试验
doi:10.1038/pr.2012.201
更新日期:2013-04-01 00:00:00
abstract::GH insensitivity may be an inherited condition or may arise as a consequence of disease of malnutrition. Laron syndrome is the most severe form of GH insensitivity, arising from an absent or defective GH receptor. Less severe forms of GH insensitivity, however, may exist, resulting in short stature but in few other fe...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-199605000-00018
更新日期:1996-05-01 00:00:00
abstract::Fetal dermal wounds heal scarlessly and with a minimal inflammatory response. When a robust inflammatory response is induced at the site of fetal dermal wounds by the application of cytokines, healing results in fibrosis. To test the hypothesis that the reduced inflammatory response in fetal wounds is due to impaired ...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/01.pdr.0000184326.01884.bc
更新日期:2005-12-01 00:00:00
abstract::Newborn rats exposed to 60% O(2) for 14 d demonstrated a bronchopulmonary dysplasia-like lung morphology and pulmonary hypertension. A 21-aminosteroid antioxidant, U74389G, attenuated both pulmonary hypertension and macrophage accumulation in the O(2)-exposed lungs. To determine whether macrophage accumulation played ...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-200108000-00003
更新日期:2001-08-01 00:00:00
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journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/01.pdr.0000183663.98446.05
更新日期:2005-12-01 00:00:00
abstract::Previous studies in mature fetal sheep have shown that alcohol depresses cerebral blood flow (CBF), cerebral O2 consumption (CMRO2), and cerebral glucose consumption (CMRglu). This effect earlier in gestation might contribute to the pathogenesis of fetal alcohol syndrome. Physiologic studies of immature fetal sheep ha...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-199206000-00021
更新日期:1992-06-01 00:00:00
abstract::To examine the levels and relationship of blood pressure and insulin during puberty, blood pressure and serum insulin were measured in 3596 subjects, aged 3-18 y, whose pubertal status was graded according to the Tanner classification. The same study protocol was repeated in two follow-up surveys 3 and 6 y later for 2...
journal_title:Pediatric research
pub_type: 临床试验,杂志文章,多中心研究
doi:10.1203/00006450-199702000-00019
更新日期:1997-02-01 00:00:00
abstract::The mitochondrial trifunctional protein (TFP) is a multienzyme complex of the beta-oxidation cycle. Human TFP is an octamer composed of four alpha-subunits harboring long-chain enoyl-CoA hydratase and long-chain L-3-hydroxyacyl-CoA dehydrogenase and four beta-subunits encoding long-chain 3-ketoacyl-CoA thiolase. Mutat...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/01.PDR.0000103931.80055.06
更新日期:2004-02-01 00:00:00
abstract::The mechanisms of how glutamine benefits critically ill patients have not been established. The purpose of this study was to determine the effects of dietary and endogenously produced glutamine on small intestinal morphology using light and transmission electron microscopy in artificially reared rat pups. It was hypot...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-200209000-00021
更新日期:2002-09-01 00:00:00
abstract::Mutations in multidrug resistance 3 gene (MDR3 or ABCB4) underlie progressive familial intrahepatic cholestasis type 3 (PFIC3), a severe pediatric liver disease progressing to cirrhosis. Abcb4-/- mice exhibit slowly developing hepatic lesions that can be accelerated by feeding a cholic acid (CA)-supplemented diet. We ...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/pdr.0b013e31802d7780
更新日期:2007-02-01 00:00:00
abstract::The key enzymes in the synthesis of the naturally occurring polyamines, ornithine decarboxylase (ODC) and S-adenosyl methionine (SAM) decarboxylase, were investigated during cell growth and aging in fibroblast cultures from normal patients and patients with cystic fibrosis. A linear correlation between increased S-ade...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-197703000-00009
更新日期:1977-03-01 00:00:00
abstract::We have previously discovered that the adult Drosophila melanogaster is tolerant to a low O2 environment, withstanding hours of total O2 deprivation without showing any evidence of cell injury. Subsequently, our laboratory embarked on the study of hypoxia tolerance using a mutagenesis and overexpression screens to beg...
journal_title:Pediatric research
pub_type: 杂志文章,评审
doi:10.1203/PDR.0b013e3181b27275
更新日期:2009-09-01 00:00:00
abstract::Pediatric research may be entering a period of failure to thrive. This is despite impressive scientific achievements, significant financial benefits, intriguing unanswered questions and a rewarding life for the pediatric researcher. Many of the difficulties are financial and situational, including small departments an...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-198506000-00019
更新日期:1985-06-01 00:00:00
abstract::The factors that mediate the postnatal fall in pulmonary vascular resistance, which is crucial for normal gas exchange, are not fully understood. The endothelium has been implicated in this phenomenon, through the release of vasorelaxant factors such as nitric oxide (NO). Human pulmonary expression of endothelial NO s...
journal_title:Pediatric research
pub_type: 杂志文章,评审
doi:10.1203/01.PDR.0000159575.58834.8D
更新日期:2005-05-01 00:00:00