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 configuration bent original configuration. At the start of the forward stroke, the cilia bear about 75-90 degrees to the epithelial surface in the direction of the forward stroke. The forward stroke is planar and consists of a simple "bowing" movement, without showing any progressive bending and without changing the original ciliary configuration. The complete forward stroke sweeps through an arc of about 35-40 degrees, with the tips of the cilia penetrating the bottom of the mucous layer through an arc of about 5-8 degrees at the start of each forward stroke. The return stroke starts from close to the epithelial surface and returns to the starting position of the forward stroke by reversing the planer forward pathway at a reduced speed. The stout nature of the cilia, the original bent ciliary configuration, the near vertical starting position of the forward stroke, the extent of the angular sweeps of the strokes, the peculiar "bowing" forward stroke movement, and the nature of the return stroke all serve to enhance efficiency in moving fluid forward. It has been documented that each forward stroke of the tracheal cilia caused and maintains a swift forward movement of the intermediate serous (liquid) layer of the mucociliary system. This movement, in turn, reacts hydrodynamically with the top mucous layer, and together with the clawing action of the tips of the cilia at the start of the forward stroke, causes the mucous layer to move cephalad in the manner of a conveyor belt.
journal_name
Pediatr Resjournal_title
Pediatric researchauthors
Cheung AT,Jahn TLdoi
10.1203/00006450-197602000-00014subject
Has Abstractpub_date
1976-02-01 00:00:00pages
140-4issue
2eissn
0031-3998issn
1530-0447journal_volume
10pub_type
杂志文章abstract::Pearson's syndrome, a rare and fatal disorder characterized by refractory sideroblastic anemia and pancreatic insufficiency in infancy, is classified into mitochondrial cytopathies. To understand the molecular and genetic bases of this disorder, we have investigated the mitochondrial respiratory chain enzymes and the ...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-199307000-00024
更新日期:1993-07-01 00:00:00
abstract:BACKGROUND:Early brain development is closely dictated by distinct neurobiological principles. Here, we aimed to map early trajectories of structural brain wiring in the neonatal brain. METHODS:We investigated structural connectome development in 44 newborns, including 23 preterm infants and 21 full-term neonates scan...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1038/s41390-018-0138-1
更新日期:2018-12-01 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::One of two slightly different influenza A/ts-1[E] recombinant candidate live vaccines was given intranasally to each of 23 young children. Twelve of 15 children who had no serum HI antibody but who did have serum ANAB at the time of administration became infected and 1 had mild rhinitis. All eight who lacked both type...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-197604000-00008
更新日期:1976-04-01 00:00:00
abstract::In Brazil, similar intrauterine growth restriction (IUGR) rates were observed between cities with distinct levels of socioeconomic development, challenging the current knowledge that higher rates of IUGR would necessarily be observed in poorer areas than in wealthier ones. Ribeirão Preto, a city located in the most de...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/01.PDR.0000156504.29809.26
更新日期:2005-05-01 00:00:00
abstract:BACKGROUND:No study has examined the association between prenatal phthalate exposure and intrauterine growth retardation (IUGR). This study aimed to investigate whether prenatal exposure to phthalates was associated with increased risk of IUGR. METHODS:A total of 126 mother-newborn pairs, including 42 IUGR cases and 8...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1038/pr.2014.103
更新日期:2014-10-01 00:00:00
abstract::The carbohydrate-deficient glycoprotein syndromes are a recently individualized group of genetic multisystemic disorders. A predominant feature is a severe involvement of the central and peripheral nervous system resulting in psychomotor retardation, seizures, ataxia, and, mostly after infancy, stroke-like episodes. T...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-199305000-00024
更新日期:1993-05-01 00:00:00
abstract::To assess the National Institutes of Health extramural activity in the area of pediatric nephrology research, the rate of submission of grant applications to the National Institutes of Health and available indicators of the quality of these applications were analyzed. This was accomplished by utilizing the grant appli...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-198511000-00001
更新日期:1985-11-01 00:00:00
abstract::BackgroundTo investigate the association between electronic cigarette (e-cig) use and smoking cessation among smokers who called the Youth Quitline in Hong Kong.MethodsThis longitudinal study collected data on youth smokers' (N=189) use and perception of e-cigs, conventional cigarette smoking behavior, and sociodemogr...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1038/pr.2017.80
更新日期:2017-07-01 00:00:00
abstract::Developmental disability, intrauterine growth retardation, renal anomalies, and dysmorphic features have been described in offspring of women who abuse toluene during pregnancy. A Sprague-Dawley rat model was developed to study this clinical syndrome. During d 6-19 of gestation, 11 treated dams received daily gavage d...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-199412000-00023
更新日期:1994-12-01 00:00:00
abstract::We investigated early postnatal changes of the mesenteric circulation and its relationship to the systemic circulation in two groups of newborn infants. Group I (n = 10) was studied before the first feeding at 1 h and preprandially at 6 and 24 h. Group II (n = 10) was studied before the first feeding at 2 h of age and...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-199409000-00011
更新日期:1994-09-01 00:00:00
abstract::Neonatal group B streptococcal (GBS) sepsis produces pulmonary arterial hypertension and hypoxemia that are preventable by pretreatment with the selective thromboxane A2 synthase inhibitor, dazmegrel. In the present experiment we administered dazmegrel (8 mg/kg) 2 h after the initiation of a 2 1/2 h infusion of 5 X 10...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-198804000-00003
更新日期:1988-04-01 00:00:00
abstract::This study was carried out to determine the influence and site of action of N omega-nitro-L-arginine methylester, an L-arginine analogue, on basal pulmonary vascular tone and hypoxic vasoconstriction in neonatal pig lungs. We studied isolated lungs from pigs, age 14.5 +/- 0.5 (SD) d and weight 3.6 +/- 0.7 kg, perfused...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-199309000-00022
更新日期:1993-09-01 00:00:00
abstract::Lipase activities were measured at pH 4 and pH 8 in the placentas of rats made diabetic by streptozotocin treatment and also in the placentas of women classified as having 1) impaired glucose tolerance or type 2 diabetes, 2) type 1 diabetes with no associated vascular complication, and 3) type 1 diabetes with associat...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-199112000-00009
更新日期:1991-12-01 00:00:00
abstract::Diabetes mellitus is characterized by microangiopathy and increased angiogenic response in various organs. Basic fibroblast growth factor (bFGF) as well as vascular endothelial growth factor (VEGF) are both angiogenic and are involved in vascular endothelial cell growth. The purpose of this study was to determine seru...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-199812000-00008
更新日期:1998-12-01 00:00:00
abstract::Sex steroids accelerate bone maturation, but it is believed that estrogen action is needed for terminal epiphyseal fusion. In this study, we investigated the effects of a new estrogen-blocking agent, Faslodex (ICI 182,780), on estrogen-accelerated skeletal maturation in immature mice. On day-of-life 2 through 8, mice ...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-199909000-00004
更新日期:1999-09-01 00:00:00
abstract::Our objectives were to establish antecedent factors and patterns of brain injury and their prognostic value in preterm infants with hypoxic-ischemic encephalopathy (HIE). Essential inclusion criteria were gestation (GA) < or =36 wk, Apgar scores <5/<7 at 1/5 min, major resuscitation at birth, and a brain MRI <6 postna...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/PDR.0b013e3181a9ef34
更新日期:2009-08-01 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::A double-label, double-substrate incubation technique has been developed and used to study the conversion of progesterone to testosterone in testes extracts from incompletely virilized males. The procedure involves separation of the microsomes from a testicular homogenate, incubating the microsomes with 1 microM [7-3H...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-198408000-00018
更新日期:1984-08-01 00:00:00
abstract::An amendment to this paper has been published and can be accessed via a link at the top of the paper. ...
journal_title:Pediatric research
pub_type: 已发布勘误
doi:10.1038/s41390-019-0680-5
更新日期:2020-04-01 00:00:00
abstract::The effects of early protein-deficiency on lung development were studied in the rat. Newborn male rats were nursed in groups of eight. Control dams and pups received a 15% protein diet during the whole experiment. Test mothers only received 12 and 8% proteins from the 7th and the 14th day of lactation. Test rats fed a...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-198707000-00012
更新日期:1987-07-01 00:00:00
abstract:UNLABELLED:The hGH response to an ornithin or an insulin test was measured in 105 children from 11-18 yr old with delay of growth more than 2 SD. Besides 74 subjects with normal values and 7 with complete lack of response, 24 subjects exhibited a partial rise of GH. Most of the latter had decreasing growth rate and no ...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-197904000-00002
更新日期:1979-04-01 00:00:00
abstract::We have previously demonstrated that vagal phase-response curves (PRC), which characterize the effects of critically timed, brief vagal stimuli on sinus node automaticity, exhibit a fundamentally different shape in the canine newborn than in the adult. In this study we analyzed the changes in sinus cycle length in res...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-199401000-00013
更新日期:1994-01-01 00:00:00
abstract::Chitosan is a natural, cationic polysaccharide derived from fully or partially deacetylated chitin. Chitosan is capable of inducing large phospholipid aggregates, closely resembling the function of nonionic polymers tested previously as additives to therapeutic lung surfactants. The effects of chitosan on improving th...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/01.pdr.0000227558.14024.57
更新日期:2006-08-01 00:00:00
abstract::We studied the effect of maternal concentration and mode of administration on transfer rate of TSH-releasing hormone (TRH) in an in vitro model of dually perfused isolated lobule of human term placenta. Varying concentrations (4-40 microg dL(-1)) of TRH were added either to the open maternal circulation to mimic an in...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-199705000-00012
更新日期:1997-05-01 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:BACKGROUND:Kawasaki disease (KD) is associated with expression and methylation of Fc gamma receptor genes. We characterized immunoglobulin A (IgA), IgE, IgG, and IgM receptor expression levels in KD. METHODS:Fc receptor expression levels were characterized using GeneChip Human Transcriptome Array 2.0 (HTA 2.0) with 18...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1038/s41390-019-0707-y
更新日期:2019-12-09 00:00:00
abstract::Epithelial hyperplasia is an early feature of the renal and biliary lesions in autosomal recessive polycystic kidney disease (ARPKD). To explore the cellular basis of this hyperplasia we isolated, cultured, and characterized biliary tract epithelium from common bile duct explants of mice with ARPKD (the BPK mouse) and...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-199506000-00014
更新日期:1995-06-01 00:00:00
abstract::Hirschsprung's disease, affecting one in 5000 live newborns, is the most common cause of neonatal intestinal obstruction. The obstruction or, later in life, constipation arises from the lack of enteric ganglia in the hindgut, thus resulting in poor coordination of peristalsis. Mutations in Hirschsprung patients have s...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/00006450-199905010-00018
更新日期:1999-05-01 00:00:00
abstract::Pulmonary surfactant is inactivated in meconium aspiration syndrome and neonatal pneumonia. Development of an exogenous surfactant less sensitive to inactivation might be useful for treating these diseases. We investigated in vitro whether addition of the cationic cyclic membrane cross-linking peptide polymyxin B (PxB...
journal_title:Pediatric research
pub_type: 杂志文章
doi:10.1203/01.pdr.0000200806.32822.e6
更新日期:2006-03-01 00:00:00