Abstract:
:We measured the changes in tidal volume, duration of the various phases of the respiratory cycle, and peak nasal pressure during elastic and resistive loading in preterm infants. Values were calculated during the first loaded breath, when chemical drive was unchanged. Tidal volume decreased by equivalent percentages with resistive loads of 400, 900, and 2,400 cm H2O/liter/sec, and elastic loads of 330, 1,000, and 3,000 cm H2O/liter. Infinite load was also applied (nasal occlusion). Inspiratory duration (ti) was prolonged during resistive loading, as compared with elastic loading (P less than 0.05). Changes in expiratory duration (Te) were not different with both loads (P greater than 0.05). Total duration of the respiratory cycle (T), however, tended to increase in relation to control, more so with resistive loads. Peak nasal pressure was greater with resistive than with elastic loads ( less than 0.025). We suggest that (1) preterm infants, like adult subjects and other animal species, increase inspiratory duration with resistive loads as compared with elastic loads; (2) T of the first loaded breath tends to increase with progressively larger loads and, consequently, instantaneous frequency tends to decrease; and (3) if peak nasal pressure reflects tension developed by the respiratory muscles, then the latter does not offer the inhibitory information needed to terminate inspiration.
journal_name
Pediatr Resjournal_title
Pediatric researchauthors
Boychuk RB,Seshia MM,Rigatto Hdoi
10.1203/00006450-197704000-00002subject
Has Abstractpub_date
1977-04-01 00:00:00pages
276-9issue
4eissn
0031-3998issn
1530-0447journal_volume
11pub_type
杂志文章abstract::A four-year-old Israeli Arab boy was found to have glycogen accumulation in both liver and muscle without clinical symptoms. Liver phosphorylase kinase (PK) activity was 20% of normal, resulting in undetectable activity of phosphorylase a. Muscle PK activity was about 25% of normal, resulting in a marked decrease of p...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-198104000-00002
更新日期:1981-04-01 00:00:00
abstract::High speed cinemicrographs reveal that the ciliary configuration and beat pattern of rabbit tracheal cilia differ significantly from classid descriptions, although the basic forward and return pattern is still observed. The tracheal cilia are short and stout (about 6 mum in length) and are of a slightly bent original ...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-197602000-00014
更新日期:1976-02-01 00:00:00
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journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/01.PDR.0000113464.93042.A4
更新日期:2004-04-01 00:00:00
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journal_title:Pediatric research
pub_type: 杂志文章,评审
doi:10.1203/pdr.0b013e31805d8a8c
更新日期:2007-06-01 00:00:00
abstract::An increase in polymorphonuclear leukocytes (PMNs) and proinflammatory chemokines, such as IL-8 and macrophage inflammatory protein-1 alpha (MIP), are found in the airways during early stages of bronchopulmonary dysplasia. We determined whether IL-10 produces a dose-related inhibition of proinflammatory chemokine rele...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/01.PDR.0000077471.36217.6E
更新日期:2003-09-01 00:00:00
abstract::Intrahepatic and intracerebral metabolic responses to neonatal fasting or enteric carbohydrate alimentation were investigated among newborn dogs. Pups were either fasted or given an intravenous glucose infusion (alimented) before an enteric feeding of physiologic quantities of either glucose or galactose. These pups w...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-198304000-00012
更新日期:1983-04-01 00:00:00
abstract::Pulmonary surfactant proteins SP-B and SP-C were isolated from lavage fluids of bovine lungs and recombined (lipid/proteins, 9/1, wt/wt) with dipalmitoyl phosphatidylcholine for testing in vitro and in surfactant-deficient adult rats. Using a pulsating bubble surfactometer, we found that inflation pressures of bubbles...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-198805000-00010
更新日期:1988-05-01 00:00:00
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journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-198107000-00014
更新日期:1981-07-01 00:00:00
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journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1038/s41390-021-01364-2
更新日期:2021-01-27 00:00:00
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journal_title:Pediatric research
pub_type: 杂志文章,评审
doi:10.1203/PDR.0b013e318212c196
更新日期:2011-05-01 00:00:00
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journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-198910000-00019
更新日期:1989-10-01 00:00:00
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journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-199508000-00005
更新日期:1995-08-01 00:00:00
abstract:BACKGROUND:Prematurity may influence the levels of amino acids, enzymes, and endocrine markers obtained through newborn screening. Identifying which analytes are the most affected by degree of prematurity could provide insight into how prematurity impacts metabolism. METHODS:Analytes from blood spots assayed by Newbor...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1038/pr.2013.212
更新日期:2014-02-01 00:00:00
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journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-200112000-00015
更新日期:2001-12-01 00:00:00
abstract::In view of the suggested relationship between substrate availability, fetal growth and circulating fetal IGF-I concentrations, we investigated the effect of maternal starvation on plasma IGF-I levels in the late gestation ovine fetus. Ten fetuses aged 125-130 d gestation were sampled daily from indwelling arterial cat...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-199004000-00015
更新日期:1990-04-01 00:00:00
abstract::Studies were designed to develop an animal model for the syndrome of hypochloremic, hypokalemic metabolic alkalosis (HMA), and failure to thrive in infants due to intake of chloride-deficient formula. Littermate canine puppies, 2 wk old, were fed soy formula containing normal chloride, 20 mEq/liter (NC, n = 5), or low...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-198705000-00015
更新日期:1987-05-01 00:00:00
abstract::To determine the pathophysiologic significance of pertussis toxin (PT) on the human beta-adrenergic system, beta-adrenoceptor (beta-R)-density and cyclic AMP response of peripheral mononuclear blood cells (MN leukocytes) were studied in children during the paroxysmal stage of natural pertussis infection, after vaccina...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-198902000-00026
更新日期:1989-02-01 00:00:00
abstract::Spring steel coils have been used to occlude abnormal vessels in patients with a congenital heart malformation. However, long-term adverse effects of steel spring coils remain uncertain, although some long-term results appear to be good. The purpose of this study was to evaluate the angiographic and histologic results...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-199804000-00016
更新日期:1998-04-01 00:00:00
abstract::Genetic factors are implicated in pathogenesis of neonatal hyperbilirubinemia. In this nested case-control study, we determined 1) frequency of thymine-adenine (TA)n promoter polymorphism and Gly71Arg mutation in uridine diphosphoglucuronate-glucuronosyltransferase 1A1 (UGT1A1) gene in neonates > or =35-wk gestation p...
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doi:10.1203/PDR.0b013e31819ed5de
更新日期:2009-06-01 00:00:00
abstract::Cardiovascular responses to feeding have been observed in several species during various periods of development and have been implicated in the development of cardiovascular regulation. In the rat, these responses are characterized by short-lasting, large increases in blood pressure (BP) and moderate increases in hear...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-199207000-00007
更新日期:1992-07-01 00:00:00
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journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-197506000-00004
更新日期:1975-06-01 00:00:00
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journal_title:Pediatric research
pub_type: 杂志文章,随机对照试验
doi:10.1203/pdr.0b013e3180459f75
更新日期:2007-05-01 00:00:00
abstract::Germinal matrix hemorrhage-intraventricular hemorrhage (GMH-IVH) commonly affects premature neonates. The gravity of the consequences associated with GMH-IVH makes it a major concern in their care. GMH-IVH begins in the germinal matrix tissue and is, most commonly, the result of venous rupture. Arteriole-to-venous pre...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-200210000-00015
更新日期:2002-10-01 00:00:00
abstract::Studies were conducted in an attempt to determine the hemolytic potential of acetylsalicylic acid (ASA) on normal intact red blood cells (RBCs). ASA (25 mg/100 ml) did not impair RBC G-6-PD, glutathione peroxidase or catalase activity, glutathione stability, or hexose monophosphate shunt activity. Hemolysis was not ob...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-197809000-00009
更新日期:1978-09-01 00:00:00
abstract::It is customary to estimate the uteroplacental function in singletons by defining appropriateness of birth weight by gestational age. Such a measure, however, is not available for the entire multiple pregnancy set. We evaluate a new index, total triplet birth weight, expressed as multiples of the median (MOM) birth we...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/01.pdr.0000202757.47761.76
更新日期:2006-04-01 00:00:00
abstract::Pregnane steroids have sedative and neuroprotective effects on the brain, due to interactions with the steroid-binding site of the GABAA receptor. In the adult brain, synthesis of the pregnane steroids is increased in response to stress. Therefore, we have used umbilicoplacental embolization to mimic chronic placental...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/01.PDR.0000088066.47755.36
更新日期:2003-12-01 00:00:00
abstract::The fetal and maternal concentration of various plasma proteins alters during pregnancy. Cells in the livers of fetal hamsters accumulate serum amyloid A (SAA) and C-reactive protein (CRP) mRNA, major acute phase reactants, when lipopolysaccharide is administered to the fetal circulation. No fetal SAA or CRP mRNA resp...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-199111000-00010
更新日期:1991-11-01 00:00:00
abstract::D-myo-Inositol 1,4,5-triphosphate (IP3) is a key second messenger in many cells, including macrophages, T and B cells, and neutrophils, in which it regulates free intracellular calcium ion levels. In human polymorphonuclear leukocytes the rise of intracellular [Ca2+] is the signal that activates a number of functions ...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-199510000-00015
更新日期:1995-10-01 00:00:00
abstract::Various assay methods for detection of thyroid hormones in human milk were evaluated in recovery and dilution experiments after which the concentrations of thyroxine (T4) and 3,5,3'-triiodothyronine (T3) were measured and compared with those in serum. The effect of breast feeding on pituitary thyroid function of norma...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-198306000-00008
更新日期:1983-06-01 00:00:00
abstract::We have investigated the impaired secretion response of neonatal platelets. We compared the response of washed neonatal and adult platelets to thrombin and collagen, and to specific activators of calcium flux (inositol trisphosphate) and protein kinase C activation (oleoyl-acetyl glycerol). Neonatal platelets show no ...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-199004000-00004
更新日期:1990-04-01 00:00:00