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Biomedical subjects

F Texier

Publications and source records attributed to F Texier.

15 recordsLinked to original sources
PubMed2000

Relative phase measurement of a stark wave packet in the vicinity of the saddle point

A gas of Rb atoms in a static electric field has been photoexcited to just above the classical ionization threshold by a phase-locked sequence of two far infrared pulses. A single laser pulse generates a series of ejected electron packets emerging at the saddle point of the potential; each of the ejected packets is characterized by a phase and a chirp. We calculate and measure these phases and chirps using the time dependent interference of the electronic wave function controlled by the delay between the two light pulses.

Journal Article↗
PubMed2000

Slow photoelectron imaging.

Experiments are reported on the detection of slow photoelectrons resulting from the photoionization of Xe atoms in a dc electric field by electron imaging. In the far-field photoelectron velocity distributions we can distinguish between direct and indirect ionization processes (involving long range Coulomb interactions with the Xe+ ion). Also, a new modulation of the velocity distribution is observed which cannot be explained by previously discussed mechanisms. Classical and quantum mechanical calculations are presented to support the interpretations.

Journal Article↗
PubMed2000

Quantum beats and Kepler motion in fast competing photoionization and photodissociation processes

Electronic and nuclear wavepackets created by coherent excitation of an autoionized and predissociated 'complex' resonance in H2 are studied theoretically using time-dependent multichannel quantum defect theory. The calculations predict that quantum beats between the components of the complex resonance interfere with Rydberg wavepacket (Kepler) motion to yield characteristic 'mixed' flux patterns in the observable time-dependent ionization and dissociation signals.

Journal Article↗
PubMed2000

[Anatomic variability and congenital anomalies of the gallbladder: ultrasonographic study of 1823 patients].

The authors report the results from the ultrasonographic exploration of the gallbladder performed on 1823 patients. They found morphologic variations and abnormalities in more than 33% of gallbladders, topographic ones in about 3.5% of observations and only 3 cases of real duplication of the gallbladder. Folds and septa may induce traps during echographic examination.

Adolescent↗
PubMed1998

Non-invasive continuous positive airway pressure in acute hypoxaemic respiratory failure--experience of an emergency department.

Non-invasive continuous positive airway pressure (CPAP) seems to decrease the need for intubation in patients with severe cardiogenic pulmonary oedema (CPO) in the intensive care unit. The goals of our study were to delineate indications for CPAP in the emergency department, and to confirm its usefulness in such a setting. We retrospectively assess the evolution of all patients ventilated under CPAP for an acute hypoxaemic respiratory failure over a 1-year period (n = 64 patients). Hypercarbia and respiratory acidosis were present in most patients with CPO (PaCO2 = 54.4+/-22.3 mmHg; pH = 7.27+/-0.13), according to respiratory exhaustion, although initial PaCO2 was low in the pneumonia group. There was a significant improvement of arterial blood gases after 1 hour of ventilation in the CPO group (PaO2 = 254.1+/-121.0 mmHg; PaCO2 = 44.0+/-12.6 mmHg; pH = 7.34+/-0.08; p < 0.0001 for both parameters). In the pneumonia group, oxygenation was also improved but with the persistence of a significant shunt (PaO2 = 157.6+/-84.4 mmHg). Fifty-four patients (84%) were considered as successfully ventilated under CPAP, with no need for intubation and a favourable evolution, mainly in the CPO group. No side effects were reported. In conclusion, CPAP is a useful and easy-to-use ventilatory device in the emergency department. It is now one of our first line treatments during prehospital and emergency care of patients with CPO.

Acute Disease↗
PubMed1987

[Asthma and pregnancy: peculiarities, therapeutic precautions].

Asthma is a very common disease and may be encountered in pregnant women. The physiological changes which accompany pregnancy, as well as the risks of drug teratogenicity and drug interactions make it necessary to take certain therapeutic precautions. Following a review of the specific respiratory physiological changes observed in pregnant women, the authors describe the risks inherent in the various treatments of asthma and the precautions to be taken during delivery and breast-feeding.

Adrenal Cortex Hormones↗