Francois Marchal

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The forced oscillation technique (FOT) is a noninvasive method with which to measure respiratory mechanics. FOT employs small-amplitude pressure oscillations superimposed on the normal breathing and therefore has the advantage over conventional lung function techniques that it does not require the performance of respiratory manoeuvres. The present European(More)
The discovery of new fossils in Africa, Asia, and Europe, and the recognition of a greater diversity in the middle Pleistocene fossil record, has led to a reconsideration of the species Homo heidelbergensis. This nomen, formulated by Schoetensack in 1908 to describe the Mauer jaw (Germany), was almost forgotten during most of the past century. Numerous(More)
A review of the published data on pharmacological closure of PDA in premature newborns shows that doses of 0.2 mg/kg indomethacin are less successful when given enterally (18 to 85% closure) than when given intravenously (88 to 90% closure). The elimination half-life is markedly prolonged in premature newborns compared to adults but there are wide(More)
Obturator hernias comprise a rare group of abdominal hernias. They are often diagnosed when the small bowel has become obstructed and the patients are operated on without the causes of the obstruction being known. Although many techniques for closure of the defect are available, there is no agreement at the present time as to which is the procedure of(More)
There is a high incidence of pediatric asthma in Vietnam, but little lung function data are available. The aim of the study was to compare respiratory resistance (Rrs), reactance (Xrs), and responses to salbutamol between asthmatic and healthy primary school children in Hanoi. Because respiratory mechanics vary along the breathing cycle, measurements were(More)
Forced oscillation impedance (Zrs) measurements are frequently corrupted by noisy data in children. Our aim was to improve the reliability of respiratory resistance (Rrs) and routine identification of its flow (V') and volume (V) dependence during tidal breathing, according to Rrs = K1 + K2 x /V'/ + K3 x V. Zrs was measured at 12 Hz, using a head generator(More)
Respiratory mechanical impedance measured at a single frequency is of great interest to describe change in airways dimensions with time in young children with asthma. Adequate filtering is mandatory in order to eliminate spurious values at rapid flow transient or during glottis closure. The aim of the study was to test a new filtering procedure. Respiratory(More)
It has recently been proposed that afferent fibers from skeletal muscle could sense the state of the microvascular circulation, linking ventilation to the degree of peripheral perfusion or vascular distension (Huszczuk et al., Respir. Physiol., 91:207-226, 1993). Ventilatory and circulatory responses to manipulation of peripheral vascular pressures in the(More)
The bronchomotor effects of a deep inhalation (DI) may provide relevant information about the mechanisms of exercise-induced airway obstruction in children and may be assessed by respiratory conductance (Grs) measured using the forced oscillation technique. The aims of the present study were to assess the effect of DI on Grs after exercise in relationship(More)
It has long been recognized that at the onset of a dynamic muscular exercise the ventilatory and the circulatory (blood flow) responses appear to be matched, thereby maintaining arterial blood gas homeostasis. Such a coupling has recently been suggested to rely upon ventilatory reflex triggered by mechanoreceptors encoding changes in muscle blood flow or,(More)