ISSN:0803-5253    

DOI:10.1111/j.1651-2227.1989.tb11302.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

ABSTRACTBeaufort‐Krol, G. C. M., Suichies, H. E., Aarnoudse, J. G., Okken, A., Jentink, H. W. and Greve, J. (Departments of Obstetrics and Paediatrics, University Hospital, Groningen, and Department of Applied Physics, Enschede, The Netherlands). Postocclusive reactive hyperaemia of cutaneous blood flow in premature newborn infants. Acta Paediatr Scand Suppl 360: 20, 1989.Reactive hyperaemia, which occurs after a period of arterial occlusion is the result of an autoregulatory mechanism, involving local factors and autonomic nerve system control. To determine this autoregulatory mechanism in cutaneous blood flow in premature newborns we measured the cutaneous reactive hyperaemia response after a 1 min occlusion, using a diode laser Doppler flowmeter applied to the skin. Twenty‐four infants with a gestational age ranging from 25 to 37 weeks and a postnatal age of 0.3 to 72 days were studied. The reactive hyperaemia response is described by the parameters maximal cutaneous blood flow (Vmax), the time to reach maximal flow (tmax), the time taken for blood flow to return to baseline following Vmax(tend) and the % increase in cutaneous blood flow above preocclusional level (overshoot). A cutaneous reactive hyperaemia response could be elicited in all infants. Following occlusion the Fmaxwas 2 640 ± 1050 mV (mean ± SD), the tmaxwas 7.6 ± 3.9 sec (mean ± SD), the tendwas 35.6 ± 14.6 sec (mean ± SD) and the overshoot was 74.6 ± 34% (mean ± SD). A negative correlation was found between hematocrit and tmax(r = ‐0.62, p<0.01). No influence of postconceptional age, postnatal age, skin and rectal temperature, incubator temperature, weight, and transcutaneous oxygen tension on the reactive hyperaemia parameters could be found. We conclude that reactive hyperaemia of cutaneous blood flow can be elicited in premature newborn infants irrespective of postconceptional age, and that the hematocrit is inversely related to the time to reach maximal flow af

ISSN:0803-5253    

DOI:10.1111/j.1651-2227.1989.tb11277.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

ABSTRACT.This paper shows how reference values can be determined when the underlying characteristic (say, weight) follows a distribution that is not too distant from the Gaussian. Application of the normalizing Box‐Cox power transformation is the basis of our approach. This transformation is monotonic and hence invertible, so offering the choice of two scales of measurement on which to work—the original and the Gaussian. Modified versions of the procedure are provided allowing use of the basic transformation in the presence of certain deficiencies in the data, principally measurement error and misclassification. It is shown that application of Box‐Cox to a cohort at several points in time can be quite revealing. When the data are already symmetrical the Box‐Cox transformation has no effect: in this case the John‐Draper modulus transformation and modifications of it are shown to be helpful. All of this is illustrated by using data from the Swedish Longitudinal Gro

ISSN:0803-5253    

DOI:10.1111/j.1651-2227.1989.tb11195.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

ABSTRACTFarthing, M. J. G. (Department of Gastroenterology. St Bartholomew's Hospital, London, U.K.). Disease‐related animal models for optimising oral rehydration solution composition. Acta Paediatr Scand Suppl 364:23. 1989.To optimise the composition of oral rehydration solutions (ORS) for European children is not a simple task. Although controlled clinical trial is ultimately the only way to determine whether a new solution is superior to an established ORS, testing many different formulations is neither feasible nor ethical. Several groups of investigators have evolved the concept of using animal models to test new ORS formulations. Disease‐related animal models using perfusion of cholera toxin‐treated rat small intestine or experimental rotavirus infection of neonatal rats suggest that optimal water absorption will he obtained by using a hypotonic ORS with a sodium concentration of 50–60 mmol/l and a glucose Concentration of 50–100 mmol/ml. Addition of citrate or bicarbonate had no benefit with respect to the promotion of water a

ISSN:0803-5253    

DOI:10.1111/j.1651-2227.1989.tb11317.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

ISSN:0803-5253    

DOI:10.1111/j.1651-2227.1989.tb11303.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

ABSTRACTIipp‐Zwahlen, A. E., Müller, A., Tuchschmid, P. and Duc, G. (Division of Neonatology, University Children's Hospital, Zürich, Switzerland). Oxygen affinity of haemoglobin modulates cerebral blood flow in premature infants: a study with the non‐invasive Xe‐133 method. Acta Paediatr Scand Suppl 360: 26, 1989.Low cerebral blood flow (CBF) is thought to cause ischaemic brain lesions in premature infants, but a normal outcome has also been observed. Low oxygen affinity of haemoglobin and high arterial oxygen content, independently, reduce CBF under normal, physiological conditions. Transfusions lower the amount of fetal haemoglobin [HbF] and therefore the oxygen affinity of premature babies. In 47 premature babies (range of gestational age 25–34 weeks, birthweight 740–1370 g), CBF was measured with the i.v. Xenon 133 method on days 1, 3 and 7. The relative amount of fetal haemoglobin [HbFj was used as a marker of oxygen affinity of haemoglobin and the haematocrit as representing the arterial oxygen content. A significant influence of [HbF]on CBF was found on days I, 3 and 7 in ultrasonographically normal babies (n = 13). In babies with subependymal and/or intraventricular haemorrhage (n = 15), this correlation was signficant only on day 3 and in those with abnormal intraparen‐chymal echodensities (n = 19) only on day 7. The correlation between haemoglobin concentration and CBF was not significant. Multiple regression analysis showed a significant influence of [HbF] on CBF independent of haematocrit, pCO2and blood pressure. It appears that, after blood transfusion, normal babies, and to a lesser extent those with haemorrhages are able to lower their CBF according to the actual oxygen affinity of blood. However, low CBF (<10 ml/100 g/min) in non‐transfused babies was often associated with later development of cystic periventricul

ISSN:0803-5253    

DOI:10.1111/j.1651-2227.1989.tb11278.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

ISSN:0803-5253    

DOI:10.1111/j.1651-2227.1989.tb11304.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

ISSN:0803-5253    

DOI:10.1111/j.1651-2227.1989.tb11205.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

ABSTRACTElliott, E. J. (Leicester Royal Infirmatory, Leicester, U.K). The role of human perfusion techniques in the assessment of oral rehydration solutions. Acta Paediatr Scand Suppl 364:31, 1989.Early human intestinal perfusion studies provided valuable information on gut transport procession in vivo. Subsequently, similar models have proved a useful means of assessing the efficacy of glucose‐electrolyte oral rehydration solutions. In contrast to clinical trials they enable quantification of water and solute movement across the small intestine and, unlike animal studies, results are directly applicable to man. However, limitations exist, including the fact that a short, usually normal, segment of intestine is studied. Recent studies confirm the relationship between oral rehydration solution sodium concentration and sodium movement; the stimulatory effect of glucose on sodium and water movement; and the detrimental effect of high glucose content. Glycine, bicarbonate, citrate and acetate provide little additional benefit for water absorption when added to solutions containing glucose. Preliminary comparative studies of results obtained in the rat and in man show parallels between these models suggesting they may be complimentary methods of assessing new oral rehydration solution

ISSN:0803-5253    

DOI:10.1111/j.1651-2227.1989.tb11318.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

ISSN:0803-5253    

DOI:10.1111/j.1651-2227.1989.tb11305.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY